United States
Environmental Protection
Agency
Environmental Research
Laboratory
Duiuth MN 55804
EPA-600-3-80-073
July 1980
Research and Development
Characteristics of
Benthic Algal
Communities in the
Upper Great Lakes
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6 Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. “Special” Reports
9. Miscellaneous Reports
This report has been assigned to the ECOLOGICAL RESEARCH series. This series
describes research on the effects of pollution on humans, plant and animal spe-
cies, and materials. Problems are assessed for their long- and short-term influ-
ences. Investigations include formation, transport. and pathway studies to deter-
mine the fate of pollutants and their effects. This work provides the technical basis
for setting standards to minimize undesirable changes in living organisms in the
aquatic, terrestrial, and atmospheric environments.
This document is available to the public through the National Technical Informa-
tion Service, Springfield. Virginia 22161.
-------
EPA--600/3-80-073
July 1980
CHARACTERISTICS OF BENTHIC ALGAL
COMMUNITIES IN THE UPPER GREAT LAKES
by
E. F. Stoermer
Great Lakes Research Division
University of Michigan
Ann Arbor, Michigan 48109
Grant Number 803037
Project Officer
Nelson A. Thomas
Large Lakes Research Station
Grosse lie, Michigan 48138
-------
DISCLAIMER
This report has been reviewed by the Environmental Research Laboratory —
Duluth, U.S. Environmental Protection Agency, and approved for publication.
Approval does not signify that the contents necessarily reflect the views and
policies of the U.S. Environmental Protection Agency, nor does mention of
trade names or commercial products constitute endorsement or recommendation
for use.
ii
-------
FOREWORD
The Great Lakes, because of their great size and long retention time
respond in slow and subtle ways to the stresses placed upon time by man.
Very often this great resource is adversely affected with the changes going
undetected for many years. These changes are difficult to detect because
only certajn portions of the ecosystem are ever examined at any one time.
Even when many trophic levels are examined, historic data bases are not
available to the investigator to look at longterm trends. One of the res-
ponsibilities of the Environmental Protection Agency is to assess the eco-
system and how it has been impacted by man. This study on the benthic algae
at the lakes provides a historic background for many of the populations.
Many old collections were examined to determine the changes that have
occurred to date and to document the species that are present so that
longterm population trends can be determined.
Norbert Jaworski, Ph.D.
Director
Environmental Research Laboratory
Duluth, Minnesota
111
-------
ABSTRACT
The upper Great Lakes contain a diverse array of benthic algal
communities. Characteristic communities occupy substrates from the
supralittoral to depths in excess of 30 m. Diatoms are the dominant
taxonoinic group present in terms of numbers, and usually in terms of biomass,
except in eutrophic areas. Communities in areas receiving minimal direct
anthropogenic impact are extremely diverse in terms of both species richness
and population evenness. The populations which comprise these communities
are generally reported from extremely oligotrophic habitats. A significant
number of populations found in undisturbed habitats in the upper Great Lakes
have not been previously reported from North America. Benthic communities in
more eutrophic areas are characterized by a greater abundance of eurytopic
and widely distributed taxa. Many of these species are familiar elements of
the floras of smaller, mesotrophic to eutrophic lakes. The communities of
directly impacted areas contain a more limited suite of very tolerant
populations, usually occurring in high abundance. Species usually reported
from saline inland waters or brackish water are a conspicuous element of the
flora in highly disturbed regions. Within any given trophic range species
richness is further modified by physical factors of the environment and
substrate availability. Community diversity is generally reduced at exposed
sites where high turbulence apparently reduces colonization potential for
some taxa. Conversely, diversity is also reduced in communities growing at
extreme depths where relatively few taxa can tolerate the very low light
conditions present. Most diverse communities are found in shallow, protected
localities and at depths where wave action is reduced. The type of substrate
available is important in determining the species which can occupy a given
site, but not necessarily important in determining overall community
diversity. The most diverse floras noted during the study were found in
epipelic communities. Many sandy substrates which show little macroscopic
evidence of algal growth have .very rich micro—algal communities. Diversity
relationships in communities attached to solid substrates is complicated by
interspecific interactions depending on the primary colonizers and subsequent
community maturation. The available evidence indicates that the range of
many oligotrophic species which originally occupied the entire upper Great
Lakes has been severely restricted. Such populations are apparently
adversely affected by very low levels of contamination, which suggests that
they may be useful in early detection of adverse trends in the system. The
recent introduction of a number of species not characteristic of oligotrophic
systems, or indeed even of freshwater lakes, indicates continuing degradation
of the upper Great Lakes.
iv
-------
CONTENTS
Foreword . iii
Abstract iv
1. Introduction 1
2. Materials and Methods 6
3. Results 9
4. Discussion 12
References 24
Table 1 — Summary of benthic diatom population distribution in the
upper Great Lakes 26
Appendix I — Plates 59
Plate I 59
Plate II 61
Plate III 63
Plate IV 65
Plate V 67
Plate VI 69
Plate VII 71
V
-------
SECTION 1
INTRODUCTION
The composition, structure, and distribution of benthic primary producer
communities in the upper Great Lakes have not been extensively investigated.
Many of the communities present are not particularly conspicuous and, while
they may be the prime food source for some invertebrates, their contribution
to the total productivity of these very large, deep lakes is probably
trivial. Most studies which have been carried out during the past several
years have concentrated on particular species or communities which may create
nuisance conditions or are strikingly indicative of ecological change. The
nutritional requirements of Cladophora and its distribution have been
extensively investigated due to the potential for nuisances caused by massive
overgrowth of this organism in areas which have been significantly
eutrophied. Cladophora overgrowths present a management problem in local
regions of the upper lakes, but eutrophication has not proceeded to the point
where they present a massive and pervasive problem as they do in Lakes Erie
and Ontario. More recently, attention has focused on the invasion and
dissemination of 3angia in the upper lakes. This organism was not noted in
the upper lakes prior to 1970. It has subsequently become established and
now forms a subdominant to dominant constituent of certain benthic
assemblages in highly Impacted areas of the upper lakes. Like Cladophora ,
this organism Is viewed as a problem because it is conspicuous. Its
preferred habitat is solid substrates within the wave zone. Its size, growth
habit, and coloration render it readily visible and identifiable
inacroscopically. These conspicuous •problem” species, however, constitute
only the highly visible end of a spectrum of highly complex and structured
algal communities which occupy benthic substrates throughout the photic zone
of the upper Great Lakes. Their abundant occurrence also, unfortunately,
signals the terminal phase of a successional pattern caused by prolonged and
extensive environmental modification.
The present study was largely motivated by consideration arising from the
two points above. If effective management of the Great Lakes ecosystem is to
be achieved, it is patently necessary to have a working knowledge of possible
pathways of nutrients and toxicants within the system. In this context,
benthic algal communities may play a larger role than would be expected on
the basis of their productivity potential since they operate at the interface
between the free water and the sediments which are the eventual repository of
most nutrients and toxicants. It would also appear that succession within
these communities might provide a particularly useful integrative assessment
of biological change within the system. In this respect, benthic algal
communities have some attributes which make them particularly desirable for
this type of qualitative assessment.
1
-------
The most obvious of these attributes is the simple fact that benthic
algal communities are more or less permanently fixed in a specific area.
This avoids a number of substantial difficulties associated with the analysis
of phytoplankton associations. Within the present state of limnological
research, it is virtually impossible to determine the history of conditions
under which the assemblage represented by a particular phytoplankton sample
actually developed. This is a particularly difficult problem in systems of
the physical dimensions of the Laurentian Great Lakes, where strong gradients
in pollutant concentrations are present and their dispersion is highly
irregular.
Another characteristic of benthic communities is their diversity. It is
quite unusual to find plankton collections with more than 100 taxa, and most
plankton communities contain only a few tens of species. Particularly in the
less perturbed regions of the Great Lakes, benthic algal communities often
contain several hundreds of taxa. Further, these very species—rich
communities generally have a very high evenness component (Stoermer 1975).
Although this aspect of benthic communities has not been thoroughly
investigated in the Great Lakes, it appears that certain communities in the
upper lakes have an unusual degree of stability. The most apparently stable
benthic algal communities are those which exist at depths approximating the
summer thermocLine. To the best of our current knowledge, these communities
exhibit very little seasonal succession, and many of the populations which
inhabit them are known from Pleistocene pro—glacial lakes. It is thus
possible that certain benthic algal communities presently existing in the
Great Lakes are largely unchanged since the formation of these bodies of
water. At the other extreme are the communities which inhabit highly
perturbed areas. En most of these communities, seasonal succession is very
intense with dominant populations being replaced several times in any given
season. In many cases, the dominant populations in these communities are
recent invaders of the system. Indeed the population succession in certain
areas of the Great Lakes during the past 3 decades is on the scale usually
associated with geological time. The extreme perturbations in certain local
areas have led to the development of benthic algal communities which
apparently have no analogues in natural environments. In other words, man’s
activities have created a unique set of environmental conditions and
generated biological responses which have not previously been observed.
Although benthic algal communities would appear to offer, in many
respects, an almost ideal tool for monitoring biotic change in large, complex
systems such as the Laurentian Great Lakes, this potential has not been
realized. There are several reasons for this.
Our present general model for practically oriented ecological studies
assumes a pre—existing framework of “classical” taxonomic and distributional
studies. Unfortunately, this assumption is not valid in the case of the
benthic algae of the Great Lakes. There are no taxonomic keys which will
cover more than a minor fraction of the taxa which occur in the system. This
means that the average investigator is faced with an almost prohibitive task
in making any meaningful analysis of the communities which are apt to be
encountered in any particular region of study. There are many species
2
-------
present in the Great Lakes flora which have only recently been reported from
North America and, indeed, many species which are apparently new to science.
Consistent and meaningful interpretation of many of the entities present in
the Great Lakes flora will demand further basic systematic research.
The remarkable diversity of habitats occupied by benthic algal
communities in the upper Great Lakes also makes community assessment
difficult. During the course of the present investigation we sampled a
number of community types which had not been previously considered. As one
example, the sand substrates which predominate in southeastern Lake Michigan
had previously been considered to be essentially “sterile” so far as
development of any extensive algal communities. Appropriate sampling of such
substrates, however, reveals the presence of a rich and diverse diatom flora.
Many of the taxa present had previously been noted occasionally in nearshore
plankton collections. Some of these species which had previously been
considered rare are actually domninants In their primary habitat.
Communities developed on sand substrates show a rather striking depth
zonation. s will be discussed more fully later, the diversity of benthic
algal communities in the Great Lakes shows a consistent trend relative to
depth. The most diverse communities are generally developed at depths
greater than approximately 10 m. It appears that this is related to reduced
wave action and the physical stability of the habitat. In general,
communities in the surf zone are less diverse than those at greater depths.
Maximum community diversity generally occurs at depths of 10—20 m. Although
viable algal communities are present to depths of 30—40 m, diversity is again
reduced, and the communities found at great depths are highly specialized and
are generally composed of a few species specially adapted to such
stenothermic and severely light—limited environments. As may well be
appreciated, this depth—related community differentiation leads to
significant difficulties in sampling. The most appropriate sampling methods
demand the use of divers and non—conventional sampling gear to satisfactorily
collect representative communities.
As may be appreciated, the characteristics of benthic algal communities
itt the upper Great Lakes and the lack of extensive previous study led to a
number of difficulties in the design and implementation of this project. The
extreme diversity of substrate and habitat types present in these large
systems make complete survey sampling almost prohibitive. Since little
previous information was available, much of the sampling undertaken was truly
exploratory and many of the collections gathered are quite probably unique.
We have attempted to accomplish two major objectives in the sampling work
undertaken. The first is to gain as good a representation as possible of
collections from the habitat types available. The second is to obtain
comparable samples from the different lakes and different areas within the
system which have been subjected to different levels of perturbation. A
completely quantitative and objective definition of this latter quality is
extremely difficult. Spot analyses of the physical conditions at the site at
the time of collection are available for most of our collections. These
analyses are, however, dubiously representative of the conditions which the
communities may be subjected to over any appreciable course of time. This
is, of course, generally true of nearshore areas of the Great Lakes where
3
-------
brief and local differences in circulation patterns and dispersion of
pollutants may grossly affect water quality. In the interest of
completeness, we have also included biological analyses of a number of
historical samples which may have limited ancillary data associated with them
or the data, if present, may be of dubious precision. Although the inclusion
of these samples is less than totally satisfactory, they do provide one of
the few available time windows whereby the modification of the lakes’ biota
may be judged. We have also included a number of “samples of opportunity” in
this analysis. These are collections added to the Great Lakes Research
Division collection which were sampled in conjunction with other projects,
but which provide information on habitats which are unusual or particularly
difficult to collect.
In many cases, particularly for species which are minor components of
older samples, the precise habitat of growth is difficult to define with
certainty. Because diatom frustules are resistant to normal decay processes,
their remains may be dispersed into other habitats. In the case of
communities which exist in high energy environments, living cells may also be
dispersed and remain viable for considerable periods of time. Some species
appear to have evolved specific adaptations which allow them to regularly
occupy the plankton. This is particularly true of certain species of
Campylodiscus, Entomoneis, Nitzschia, Plagiotropis , and Surirella . All of
these entities find their primary habitat in epipelic habitats, but are
regularly noted in plankton collections. Particularly in shallow, severely
eutrophied areas within the Great Lakes, such species may be important
elements in plankton assemblages under certain conditions. Although they
very rarely are numerical dominants in the flora, cells are relatively large
and they may constitute an important component of phytoplankton assemblage
biomass. Perhaps the most striking example of this is the distribution of
Surirella angusta in Lake Ontario. Although this species is most commonly
epipelic, it is an important element of plankton throughout Lake Ontario
during the winter circulation of the lake. Although it may be argued that
the terms are nearly synonymous (Hutchinson 1967) we have chosen to
distinguish between tychoplanktonic and pseudoplanktonic. In this report we
will apply the former term to species, such as the ones just described, which
are regularly found in plankton collections and which appear to have the
capability to occupy alternate habitats successfully. The term
pseudoplanktonic will be reserved for cases where the incorporation of a
particular taxon in the plankton is not apparently ’ due to biological
adaptation and where the entity is incapable of significant growth or
reproduction in the plankton.
While this type of cross utilization of macrohabitats is, at least in
many instances, relatively easy to define, the specific habitat requirements
are much more difficult to deal with. Many of the communities treated in
this study are structurally very complex. Perhaps the nearest terrestrial
analogue is the situation found in tropical rain forests. Although the
actual ranges of physical and chemical conditions which may occur within
complex algal communities are poorly documented, it is obvious that there is
significant within—community differentiation of growth habitat and occupancy
among the species which compose a given community. It is thus perfectly
plausible that species having both high and low light requirements could
4
-------
occupy different physical strata in the same community. It is also quite
possible that a species having a requirement for substantial organic loadings
could find a suitable niche within a complex community growing in an
otherwise “oligotrophic” environment. This type of specific microhabitat
requirement may explain the apparent wide distribution of some species which
are always rare in occurrence. Of particular interest to this study, it may
serve to explain the apparent disjunct occurrence, in very low numbers, of
species which are usually associated with nutrient or organically enriched
environments in some complex algal communities in relatively pristine areas
of the Great Lakes. This type of microhabitat differentiation is very
difficult to deal with in a study of this type since real resolution of
community physical structure demands application of advanced techniques and
considerable expenditure of effort. Although this type of resolution is
certainly desirable, and probably necessary to the fundamental solution of
some problems in algal community ecology, it is beyond the scope of an
exploratory investigation of the type undertaken here. It must be
remembered, however, that the sampling methods employed in this project
resulted in the collection of entire communities, and that the fine—scale
differentiation of micro—habitats which may occur within the communities is
submerged.
Some of the information generated during the course of this study has
been independently published in the journal literature. A summary of
diversity trends in communities in Lakes Michigan and Superior was compiled
during the initial phases of the project (Stoeriner 1975). The trends
illustrated by these initial samples appear to be general. Information from
this project has also been incorporated into an initial checklist of diatom
taxa known to occur in the Great Lakes (Stoertuer and Kreis 1978). This paper
also reviews the literature pertaining to diatoms in the Great Lakes. The
problems of accurate species identification when dealing with an extremely
diverse and poorly known flora are frustrating and considerable basic
taxonoinic work remains to be done. We have documented new records of taxa in
certain genera (Stoermer 1978, Stevenson and Stoeriner 1978, Kreis and
Stoermer 1979) but numerous new records remain to be published. The
disposition of entities which are niorphologically unique but not, at this
point at least, identifiable with described taxa is more vexing. We have
accumulated records of a large number of such apparently undescribed taxa
during the course of the study. In many instances, they are very rare in
occurrence and further collections would have to be made in order to document
their range of variability. There are, however, a number of unknown taxa
which are numerically important or even dominant elements of communities
investigated. Description and formal publication of these entities will
require further research.
5
-------
SECTION 2
MATERIALS AND METHODS
A large variety of methods were used in the collection of samples
reported here. Shallow water communities were collected by hand techniques
appropriate to the substrate sampled. Whenever possible, a portion of the
actual substrate was included in the sample to assure that all taxa
characteristic of the site were included in the sample. In the case of
massive and well—indurated substrates, it was necessary to scrape the
material from the substrate. In many cases it proved desirable to utilize
SCUBA gear even for shoreline collections, since it substantially improves
access to communities which grow within the wave zone.
SCUBA was used extensively to sample communities occurring at depths
beyond a few meters. Whenever possible, portions of the substrate were
collected into containers and transported to the surface for further
subsampling. The most convenient containers for solid substrates were found
to be semi—rigid plastic boxes with “snap on” tops. They are relatively easy
to handle with gloves, protect samples from damage, and are readily available
at low price. Unconsolidated samples were collected by diver—operated short
corers and the corers transported to the surface intact for subsampling. In
general, SCUBA or surface supply diving were the preferred methods of
collecting. They allow much greater selectivity and differentiation of
micro—conmiunities which would otherwise be neglected. One of the more
interesting observations derived from diver sampling is the presence of
occasional large “beds’ of macroscopic green algae such as Chara Nitella , and
Dichotomosiphon . These communities are very patchy in distribution, usually
occurring in silty—sand substrates at depths from 10 to 20 m. Growth is
uncommonly luxuriant, with Nitella plants commonly reaching 30 cm or more in
height and Dichotomosiphon beds 15—20 cm. Very little is known about the
extent or ecological importance of these communities. We have observed them
in numerous localities, particularly in Lake Michigan. Masses of
Dichotomosiphon have been reported to cause occasional problems at the
Chicago water filtration plant by fouling trash screens at intakes. These
instances usually occur after strong fall storms. Our sampling at these
communities was limited, but they probably deserve further attention as they
obviously furnish the preferred habitat of many invertebrates and fish.
Some of the samples reported were taken by conventional over—the—side
ship sampling gear. Many of these collections were samples of opportunity,
taken in conjunction with projects designed to gather other types of
information. Solid substrates were collected by PONAR dredge and
occasionally by rock dredge. Unconsolidated sediments were taken by a
BENTHOS corer and the epipelic communities in the upper few millimeters of
6
-------
the sediment were subsampled. These sampling methods are essentially “blind”
and have a number of undesirable features. Samples taken by dredge are
subject to some degree of disturbance and possible mechanical damage. The
nature and degree of displacement of components of any particular community
sampled is difficult to determine after sample recovery. This problem is
less acute with core samples, which preserve fine features of sediment
structure, and presumably biological community structure, with remarkable
fidelity. With any of these techniques it is, of course, impossible to
determine how characteristic the community recovered is of the environmental
mosaic of the local area sampled. In the case of rock dredge samples, and to
a lesser extent with other types of dredges, it is difficult to determine the
precise depth and location of sampling.
Some of the most interesting samples from extreme depths analyzed during
the course of this project were taken by the submersible STAR II during
relatively brief operations in the Great Lakes a number of years ago. Only
solid substrates were sampled, but these collections provide our only insight
to the potentially interesting bryophyte associations which exist at depths
of 30 m and greater in the Great Lakes.
In all instances samples were preserved immediately after collection.
The most commonly employed fixative was formalin—alcohol, although
glutaraldehyde and gluaraldehyde—paraformaldehyde were employed in some
instances. These fixatives provide superior preservation of cytoplasmic
structure.
After return to the laboratory, samples were split. One split was
subsampled for observations on soft—bodied forms and the remainder
permanently preserved as an archival sample. The second split was cleaned
(Patrick and Reimer 1966) and subsamples of the cleaned material were
prepared as strewn diatom mounts in HYRAX. Duplicate strewn diatom slides
are preserved from each collection and the cleaned material is permanently
preserved. Thus, four permanent samples are retained from each collection;
preserved raw material, cleaned material, and duplicate prepared diatom
mounts.
In an effort to gain some historical perspective on the trends in
benthic algal distribution in the upper Great Lakes, we undertook
considerable effort to locate and analyze historic samples from the region.
The results of this effort were instructive but, to some degree, frustrating.
Most of the material located consists of prepared diatom mounts. In most
instances these are only a single slide which reached a permanent repository
through exchange. In many cases the information regarding the site of
collection and conditions are fragmentary and, in a number of instances which
we investigated, the actual physical site of collection does not presently
exist. This is particularly true of historic samples from the Chicago area
where pre—1900 shoreline localities are now hundreds of meters inland due to
bulkheading and filling in the lakefront. Even given these difficulties,
these collections furnish a valuable record of biological change in the
region. It is extremely unfortunate that more investigators do not follow
simple good scientific practice by depositing permanent reference sets of
their material. This is especially true of studies which involve
7
-------
documentation of system response to specific environmental modifications. It
is interesting to note that most of the collections recovered come from
institutions in the eastern United States and Europe. The development of an
adequate regional repository would certainly aid future investigators.
Population estimates from strewn diatom mounts were developed by
identification and enumeration of specimens observed on multiple strip
counts. Identification and counting was carried out at ca. 1200X using a
microscope capable of providing at least 1.32 N.A. Identifications and
numerical data were encoded and machine processed. Preliminary data
reduction was accomplished through programs developed in our laboratory
(FIDO) which calculate absolute and relative abundance estimates and
associated error, diversity, and redundancy (ANALYZE). Reduced data are
stored in sequential tape files. Summary information regarding number of
occurrences and least and greatest abundance for all taxa in a given set
(SUMMARY), or detailed information regarding a given taxon (FETCH), may be
recovered from these files. Summary collection records are also available in
the same format. Although this information is too extensive to reproduce
here, interested parties may obtain it by requests directed to the author.
8
-------
SECTION 3
RESULTS
The most economical and efficient method of conveying the information
contained in a large exploratory data set of this type is something of a
problem. We have attempted to tabulate the information in summary form.
Even recognizing that strict categorization of the variable involved in a
limited number of cases is not entirely appropriate, we feel that this is the
most informative approach at the present time. Since we are dealing with
many organisms which have not been subjected to experimental investigation,
and indeed many which are relatively rarely reported, a more detailed
approach is probably not justified. The summary we have adopted is given in
Table 1 following.
In Table 1 the degree of environmental modification is categorized
according to the following classes:
I. Refers to regions which are isolated from direct pollution sources
and are the nearest modern analogues of the original state of the system.
Examples would be isolated shoreline localities in Lake Superior and northern
Lake Huron and the offshore islands and reefs of northern Lake Michigan. The
extreme examples covered in this case are areas such as Superior Shoal in
Lake Superior which is probably the most nearly pristine area sampled and
which does have special floristic characteristics.
II . Refers to regions which are marginally impacted. This would
include shoreline localities south of Saginaw Bay in Lake Huron and south of
Ludington in Lake Michigan.
III. Refers to regions which are highly impacted. Examples would be
Saginaw Bay in Lake Huron, southern Green Bay in Lake Michigan, and the lower
Duluth etubayment in Lake Superior. Also included are localities in the
vicinity of major streams entering Lake Michigan and localities in the
vicinity of direct discharges.
The observed abundance of a particular taxon within a region is
designated according to the following code:
D — Dominant populations comprising more than 20% to the total
assemblage
A — Abundant populations comprising 5—20% of the total assemblage
C — Commonly observed populations comprising 1—5% of the total
as semblage
R — Rare populations comprising less than 1% of the total assemblage
9
-------
V — Very rare populations few or single examples noted in the assemblage
The apparent habitat preference of a given taxon is specified according
to the following code:
P — Epithytic
PP — Epiphytic species particularly associated with other algae
PV — Epiphytic species particularly associated with vascular plants
PB — Epiphytic species particularly associated with aquatic bryophytes
S — Epelic
SS — Epelic on sand or fine gravel
SF — Epelic on fine unconsolidated sediments, including organic
sediments
B — Epipilhic
T — Tychoplanktonic, a somewhat special category indicating how
regularly a particular taxon occupies planktonic assemblages
There is obviously a good deal of variation in the degree of specificity
of a particular taxon to a particular substrate or habitat type. In some
instances the requirement is quite specific. Examples of this would be the
occurrence of Ptchnanthes hungarica on Lemna or the association of Navicula
contenta fo. biceps with bryophytes. We should also caution that, whenever
possible, we have attempted to designate the specific habitat of occurrence.
Thus a species of Epithemia growing on depauperate Cladophora in crenulated
limestone, as is common in northern Lake Huron, would be designated as “PP.”
If the specimens are so rare that the actual microhabitat was not observed,
the more general habitat category is given. Much further research is needed
to resolve the questions revolving around microhabitat specificity versus
general ecological conditions.
As will be noted in the table, the specific growth habits of the taxa
treated, if known, are indicated by a subscript according to the following
code:
a — Attached organisms having particular morphological modifications of
structures which allow them to remain sessile on a substrate
c — Colonial species which may be entwined within a complex community
but which are- not directly attached to a substrate
v — Vagile species which freely move through the matric of complete
communities or upon substrates
There are a number of usually sessile taxa which may become motile in
response to particular conditions. In the following compilation, the usual
growth habit observed is reported.
The apparent depth zonation preference exhibited by the populations
treated in this study are designated by the following code:
S — Shallow water, less than 2 m depth, strongly affected by wave
action
Sp — Same depth zone as above but designating localities which are
protected from strong wave action
10
-------
I — Intermediate depths, 2—10 tn
D — Deep stations, 10—30 in
D+ — Used to designate taxa which were noted exclusively from very
deep stations
The depth components contains factors affecting both the physiological
mechanisms of cells, such as light quantity and quality, nutrient
availability, and temperature and purely mechanical factors. It is clear
that the latter factor is important, since our data indicate that many
populations which are usually found in the intermediate depth range are also
capable of developing in shallow water in protected areas. On the other
hand, it is clear that a significant number of populations, particularly in
areas which have not been severely polluted, are specifically adapted to
occupy the zone of near constant temperature and nutrient conditions below
the normal excursion of the summer thermocline in the upper Great Lakes.
These populations are probably most sensitive to incipient eutrophication.
11
-------
SECTION 4
DISCUSSION
On the basis of this study, it is clear that several factors must be
accounted for in any meaningful discussion of distribution trends in benthic
diatom assemblages in the upper Great Lakes. These include both natural
characteristics of the environment and modification apparently brought about
by human activities.
Reference to historic collections provides convincing evidence that
certain particularly sensitive species, such as Didymosphenia geminata , have
been excluded from significant portions of the system during the period of
record. It is unfortunate that the history of this floristic change cannot
be determined in greater detail so that we might gain some insight into
critical levels of effect. The historic record is fragmentary, at best, so
that this method of comparison is effectively closed.
Comparison of communities occupying physically similar habitats in
different areas of the system, provides convincing evidence that
anthropogenic effects result in a reduction in community diversity. Our
results also indicate that both the richness and evenness components of
calculated diversity indices are reduced. In other words, there appears to
be an absolute reduction in the number of species which can occupy a given
habitat at any particular time plus a disproportionate increase in the
abundance of certain species tolerant of altered conditions. Reduction in
diversity of this type is commonly observed in highly impacted areas and is
well documented in the literature as attested to by the fact that diversity
indices are commonly used as an index of biological “health” of a water body.
It is particularly interesting that population exclusion and diversity
reduction in Great Lakes benthic algal communities apparently begins at very
low levels of perturbation and community diversity may be reduced even in
situations which would be characterized as oligotrophic by most conventional
rating criteria. Such sensitive biological measures may become increasingly
useful as gross and obvious sources of pollution are brought under control,
thus allowing more consideration and effort to be devoted to the real problem
of maintenance and/or restoration of ecosystem function. It may reasonably
be argued that such measures of ecosystem quality are particularly applicable
to large, high quality and long residence time systems such as the Great
Lakes. There is a tendency to ascribe the obvious and well documented
symptoms of ecosystem disfunction, such as the collapse of major fisheries
stocks, to equally obvious ecological insults such as the introduction of
toxic materials, exotic competitor populations, or simple over—exploitation.
Although the case is not as well documented, it is quite clear that equally
large changes have taken place in primary producer communities which were
12
-------
subjected to different types of stress. It is entirely plausible that
effects at the primary producer level are propagated through the ecosystem to
the eventual detriment of the terminal elements of the food chain and that
effective management will demand actions to prevent modification of the
segment of the ecosystem.
As indicated in the introduction, benthic algal communities would appear
to be sensitive indicators of change. Although the results of the present
study are indicative of the type of information which can be gained through
this approach, it is apparent that further basic investigations are necessary
in order to utilize it as a management tool. On the basis of our results, it
may be confidently projected that the basic inventory of populations which
occupy the Great Lakes is far from complete. It would seem reasonable that
some effort be devoted to developing this type of very basic information.
Further, this type of basic information needs to be systematized in some form
that is readily available to investigators working on practical problems in
environmental management. At the present time, accurate identification of
benthic algal populations in the Great Lakes depends very strongly on access
to the primary literature. Until reasonably comprehensive taxonomic
treatments of the Great Lakes flora are developed, most investigators will
find analysis of benthic algal communities in the lakes a very time consuming
and substantially frustrating task.
Within the present state of the art, useful information regarding the
state of particular areas within the system can be gained through study of
benthic algal communities. Cautious and thoughtful application of the
classical indicator species and diversity concepts can yield information that
is difficult, if not impossible, to obtain through other approaches.
Although these approaches have been criticized, the fact remains that major
compositional or structural changes in a system are important events and any
management system which is incapable of sensing such events is liable to
serious errors. Most of the problems which arise from attempts to utilize
such qualitative measures of ecosystem quality result from misapplication or
overextension of the approach.
In the case of communities in the Great Lakes, application of the
diversity approach is liable to misinterpretation unless physical factors of
the environment are taken into account. Our results show that communities
which develop in high wave energy environments are, as might be expected,
considerably less diverse than communities which develop in either more
protected localities or at depths sufficient to reduce wave energy. This
tendency appears to be general, so that habitats exposed to extreme periodic
turbulence have significantly less diverse floras regardless of other
factors. Our results in fact suggest that the heavy growths of Cladophora
which develop in highly eutrophic regions may allow the temporary development
of more diverse associated micro—algal communities than are generally
characteristic of exposed sites in less productive areas. This situation
generally occurs in the fall, following the grand growth period of Cladophora
and before strong fall storms result in the destruction of the complex
community matrix. Significant reductions in community diversity are also
observed in communities living at depths greater than Ca. 20 m. Apparently,
relatively few populations are able to adapt to the low light environment
13
-------
present. The most curious situation occurs in bryophyte dominated
communities which are found at depths of ca. 30 m in Lake Michigan. A large
number of only a few species of diatoms are found associated with these
communities and most abundant of these are the same species which are found
in terrestrial moss communities. The most characteristic species is Navicula
contenta fo. biceps . The factor or factors which could be common between
aerophytic habitats and the conditions found at depth in Lake Michigan are
difficult to imagine. It may be that these species are heterotrophic and
require some specific material generated by the moss species they live upon,
or the relationship may be a structural adaptation, since the diatoms apppear
to have functional chloroplasts. Such specific associations may be more
common than generally realized and, unless recognized, complicate the
association of particular species with commonly measured environmental
variables.
An example of this type of modification is found in the invasion of
Bangia in Lake Michigan. This primarily marine species was first noted in
Lake Erie in 1969 (Kishler and Taft 1970). We first noted it in Lake
Michigan in 1972. The material occurred in beach seine collections from near
the D. C. Cook nuclear power plant near Benton Harbor, Michigan. Due to the
method whereby the material was obtained, the exact habitat of growth is
unknown. Later observations along the Michigan coastline of Lake Michigan
showed that Bangia populations were established at many localities where
suitable substrates were present near the mouths of major streams entering
the lake. During the early stages of Bangia invasion, it appeared to be
limited to particular growth habitats and seasons. Established Bangia mats
were usually found in the splash zone on rock or concrete substrates, and
were only obvious during the early spring and late fall. It thus appeared
that Bangia was replacing the Ulothrix zonata association which had
characteristically dominated the habitat during the cold months of the year.
The characteristics of the thallus and growth habitat of Bangia and Ulothrix
are quite similar. Apparently because of the large, diffluent sheath
characteristic of both taxa, neither supports an appreciable epiphyte flora.
Since becoming established, however, Bangia has expanded its local range of
occurrence, both temporally and spatially. During the past few years,
luruxiant growths of Bangia have been noted in highly impacted areas
throughout the year, except during periods of heavy ice scour. Furthermore,
it appears to have adapted to a much wider range of physical habitats, and
extensive beds are found on submerged rocks and other solid substrates. This
species thus appears to be competing successfully with Cladophora glomerata
in highly impacted areas. It is reasonable to project that this will have a
significant effect on the composition and diversity of the total algal
assemblage found in such areas. Unlike Bangia, Cladophora supports an
extremely rich and diverse epiphyte flora. Although the extreme overgrowths
of C. glomerata characteristic of eutrophied areas have caused this organism
to be regarded as a nuisance, it should be pointed out that species of
Cladophora are present throughout the Great Lakes system wherever suitable
substrates and physical conditions exist. It usually forms a significant
part of the “fabric” of benthic algal associations found on solid substrates.
This is true even of associations in the most “oligotrophic” parts of the
Great Lakes system, such as the epilithic communities found on Superior Shoal
in Lake Superior. The replacement of Cladphora by Bangia in highly impacted
14
-------
areas could thus signal a very extensive change in the entire algal
association characteristic of such areas and a concomitant modification of
the food base available to consumer organisms. Within the present state of
knowledge, the eventual impact of such changes is almost impossible to fully
project. It is clear, however, they are indicative of biological responses
to ecosystem stress which propagate widely through the system. In the
particular case of Bangia , this exotic population has now become a major
element of epilithic communities in impacted areas throughout Lake Michigan
and southern Lake Huron. We have not noted it in Lake Superior.
While. microhabitat interactions make it difficult to infallibly
characterize the relationship of particular populations to conurtonly measured
water quality parameters, a number of trends of occurrence are obvious in our
data. The clearest associations, as might be suspected, occur at the
opposite ends of the spectrum of conditions found in the modern Great Lakes.
On the basis of our observations, a number of populations are
exclusively associated with relatively high conservative ion and nutrient
loadings. Most of these populations find their primary habitat in various
benthic algal communities in brackish water situations. Included in this
group are species such as Bacillaria paxillifer, Synedra fasciculata , and
S. pulchella . Although occasionally reported from inland waters with high
total dissolved solids, these species are clearly indicative of extreme
conditions in the Great Laker system. Although not noted in our collections,
Terpsinoe musica Ehr., a species often abundant in brackish water and
subtropical rivers, has recently been reported from Lake Michigan (Wujek and
Welling 1979). The same authors also reported the occurrence of Biddulphia
laevis Ehr. This species and others, such as Pleurosigma delicatulum , are
also associated with high total dissolved solids, but usually in inland
waters. Ti e above species are often dominant populations in rivers in the
western United States. Anomoeoneis costata is another species apparently
tolerant of extreme osmotic stress. It is rare in the Great Lakes and
restricted to grossly modified habitats, but is fairly widely distributed in
eutrophic freshwater lakes. It reaches its maximum abundance in sodium
carbonate lakes in endorheic regions and may be a dominant population of the
restricted flora present in such lakes.
In a very real sense, these species represent the cutting edge of change
in environmental quality in the upper Great Lakes. They are adapted only to
the extreme of conditions generated by human activities.
The opposite end of the spectrum is represented by those species which,
also in a very real sense, represent the trailing edge of floristic
succession. Included in this category are entities such as Melosira arenaria
which are best adapted to extremely oligotrophic and boreal conditions. In
the fossil record of lakes formed during the Pleistocene they are considered
indicators of proglacial lake phases (Stoermer 1977). Their continued
existence in the upper Great Lakes apparently depends on sufficient light
penetration to depths below the excursion of the summer thertuocline which
provides a niche for organisms adapted to low, and essentially invariant
temperature conditions, in combination with very low levels of nutrients and
other dissolved materials. It has been previously pointed out (Beeton and
15
-------
Chandler 1966) that one of the unique characteristics of the Great Lakes
fauna and flora is the extension of the latitudinal range of many primarily
boreal species and the preservation of many “glacial relicts.”
It is thus not particularly surprising that a disproportionate number of
the species listed here are known primarily or exclusively from boreal
localities and are often abundant in Pleistocene deposits. On the basis of
our results, it is evident that the range of occurrence of many of these
species is restricted in the modern Great Lakes. The best documented cases
are large, conspicuous periphyton species such as Didymosphenia geminata . Due
to the fact that this species is so distinctive that it would be consistently
recognized, sufficient records are available to support the contention that
it was originally present throughout the upper Great Lakes. At the present
time,populations are restricted to Lake Superior. As will be noted from the
compilation, a large number of species have similar patterns of modern
distribution and we suspect that they were originally more widely
distributed, although this cannot be proven on the basis of available
records. Included In this group are several species of Achnanthes ,
particularly A. calcar , A. kryophila , A. levanderi , members of the
A. oestrupi complex, and A. suchlandti . A number of species in the genus
Diploneis are also known primarily from either boreal or fossil localities
and are now restricted to the less modified parts of the upper Great Lakes.
Included in this group are species such as D. boldtiana , D. domblittensis ,
D. finnica , and D. parma .
Observations on the limited number of historic samples which were
available for study also support the contention that the range of many
benthic diatoms has been restricted. Most of the samples which we have
observed came from the Chicago region of Lake Michigan and many were
collected In an attempt to study what were perceived as deleterious changes
in the lake in the period from 1870 to 1890. Although not representative of
pristine conditions, it will be noted that a large number of taxa were either
much more abundant in the early samples than they are now, or present in
those samples but not observed in modern Lake Michigan.
Firm interpretation of this pattern is limited by two factors. The
first is our lack of knowledge of the growth habitat and distribution within
the lake of many of these species. Perhaps the outstanding example of this
is found In the distribution of several species of the genus Amphora in Lake
Michigan. We originally reported the presence of several of the e on the
basis of rare occurrences in plankton collections (Stoermer and Yang 1971).
Subsequent research has shown that they are, In fact, abundant in communities
growing on the supposedly “sterile” sand substrates which are the primary
available habitat In the southeastern part of the lake. Such substrates are
rarely collected and the associated algal flora remains poorly known. It is
possible that some of the more sensitive species which originally inhabitated
the Chicago area still exist in isolated localities in northern Lake
Michigan. The most probable localities are those in which the eutrophication
of Lake Michigan is somewhat mitigated by exchange of water with Lake Huron
(Scheiske et al. 1976). The second factor is that the historic records are
not sufficiently detailed to establish either the trend of exclusion of
sensitive species or any correlation with levels of nutrients or other
16
-------
factors. In the case of Didymosphenia geminata , it can be established that
the species was abundant in the Chicago region in the 1870s (Briggs 1872) and
still present in the 1880s (Thomas and Chase 1887). Populations were taken
in deep water plankton tows in Grand Traverse Bay in the 1890’s (Thompson
1896). Further verifiable records are lacking. The available water
chemistry data is not sufficiently sensitive to allow the establishment of
causal connections. Even at the present time, measurements of available
nutrients in the range of interest are subject to appreciable uncertainties.
Direct experimental evidence of the range of tolerance of these species is
entirely lacking. So far as we have been able to determine, practically none
of the species which are characteristic of undisturbed habitats in the upper
Great Lakes have successfully been cultured in defined media.
On the basis of our observations, it appears that a considerable number
of species which are restricted to Lake Superior in their modern distribution
probably did not inhabit either Lake Michigan or Lake Huron in their
unaltered states. Included in this group are several members of the genera
Anomoeonesis, Eunotia , and Pinnularia which are characteristic of dystrophic
lakes or other bodies of water with very low mineral solids content.
Apparently due to natural drainage basin characteristics, the waters of the
lower lakes did not furnish a suitable habitat. As will be noted from the
compilation, some of these species are noted very rarely in collections from
near river mouths in Lake Michigan. These specimens are probably derived
from the drainages of dystrophic lakes or bogs and probably do not survive in
Lake Michigan proper.
It should probably be pointed out that, with the exception of a few
essentially monospecific genera, there is relatively little consistency in
the distribution patterns of various species of most of the major genera
found in the Great Lakes. Several genera have species which occupy opposite
ends of the range of conditions which occur in the system. For instance,
although Melosira arenaria is characteristic of extreme oligotrophic
conditions, M. varians is usually found in very highly productive conditions
and seems to be associated with relatively high organic loadings. As pointed
out earlier, knomoeoneis costata is largely restricted to areas where the
waters have elevated dissolved solids content but A. follis is found only in
waters with extremely low total dissolved solids. In these particular cases,
it could be argued that this is the result of a highly artificial
classification. In both of the cases cited above, there are significant
morphological differences between the species compared and in both cases they
might be placed in different genera under a more natural classification
system. However, even in genera where such differences are not obvious, we
still find extreme distributional differences among the members of a given
genus. The most striking differences are found among some of the larger
genera such as Cymbella Gomphonema Navicula , and Nitzschia , all of which have
species which occur more or less abundantly in various segments of the range
of conditions found in the upper Great Lakes.
In the genus Achnanthes , species such as A. delicatula , A. hauckiana ,
and A. hungarica are usually restricted to highly impacted areas. A number
of common eurytopic species such as A. conspicua , A. lanceolata , and
A. minutissima are common in areas which are significantly eutrophied.
17
-------
Achnanthes affinis and A. minutissima are apparently tolerant of nutrient
addition, but are also quite abundant in more oligotrophic regions. Together
with species such as A.. duthii , A. kryophila , A.. oestrupi , and A. peragalli ,
they are characteristic of habitats which have received little disturbance.
The most oligotrophic associations contain species such as A. calcar ,
A. flexella , A. gracillima , and A. subsaloides .
The distribution of members of the genus Amphipleura in the upper Great
Lakes is somewhat unusual. Of the two species noted, A. arctica is
substantially restricted to relatively unmodified parts of the system, but
A. pellucida is very widely distributed. It is found in benthic associations
throughout the region and may be present in significant quantities in
plankton collections from disturbed areas. High populations of this taxon
are characteristic of the Green Bay water mass and it is often found in
abundance in the plankton of other more eutrophic regions of the lake.
Due to their habitat preference, the distribution of many of the species
of Amphora occurring in the upper lakes has not been well documented. They
are generally most abundant in epipelic communities, particularly in deep
water. Species characteristic of disturbed areas include A. montana ,
A.. normanii . A. veneta , and A. ovalis. The latter species appears to be more
eurytopic than the others and its range e ctends into more oligotrophic
habitats. Species such as A. calumetica , A. huronensis , and A. michiganensis
are often relatively abundant on sand substrates in relatively little
disturbed areas. In our collections, A,. veneta var. capitata has been noted
only in collections from areas receiving little disturbance. Previous
records of this taxon are mostly from fossil localities.
Members of the genus Anomoeoneis are relatively rare components of
benthic algal cominunit ies in the upper Great Lakes. As indicated earlier,
A. costata is found only in highly disturbed habitats and is usually
associated with very high total dissolved solids concentrations, indicative
of disturbance in the Great Lakes. The other members of the genus reported
are all characteristic of oligotrophic hab1ta s and/or dystrophic habitats.
Of these species, A. vitrea is by far the most common and widely distributed.
The growth habit of this species is very unusual. It is usually free living
and vagile, but may grow in large gelatinous masses and occasionally forms
apical stalks, similar to Gomphonema . Specimens with this growth habit may
be asymmetric, although similar to the “normal’ form in other respects. The
stalked form may be a cryptospecies, which has some interesting systematic
implications, since the nonienclatural type is stalked.
Members of the genus Caloneis are generally minor components of the
benthic communities investigated. The largest and most conspicuous member of
the genus, C. amphisbaena , is restricted to eutrophied habitats. It is most
abundant in epipelic communities in Saginaw Bay, Green Bay, and some of the
salinified rivers entering Lake Michigan. The most widely distributed
species is C. bacillum and its varieties, which is widely distributed
throughout the upper lakes. Species such as C. limosa , C. nubicola , and
C. ventricosa appear to be restricted to areas which have not been
significantly disturbed.
18
-------
Most members of the genus Cocconeis found in the upper Great Lakes are
distributed throughout the system. Cotutnon species such as C. diminuta ,
C. placentula , and C. pediculus occur in very oligotrophic habitats but are
more abundant in areas which are somewhat enriched. In the case of
C. pediculus , particular abundance appears to be at least partially
controlled by availability of suitable substrate. This species is a dominant
epiphyte on Cladophora glomerata and its abundance is correlated with heavy
growths of Cladophora . The sole exception to this type of general
distribution pattern is found in C. placentula var. rouxii . This taxon is a
dominant in collections from Superior Shoal, but essentially absent from
other parts of the system.
An unusually large number of species of Cymbella occurs in the upper
Great Lakes. Very few members of the genus are found in saline waters, and
the Cymbella flora of local regions in the Great Lakes system which receive
heavy conservative ion loadings is notably depauperate. Large populations of
species such as C. affinis and C. prostrata are characteristic of eutrophied
regions and these species, plus others such as C. cistula and C. mexicana ,
remain abundant in areas which receive relatively small nutrient loads.
Relatively isolated regions in northern Lake Michigan and Lake Huron have
very diverse assemblages of species of this genus. Species such as
C. angustata , C. cesatii , C. cistula var. gibbosa , C. delicatula , C. latens ,
and C. proxima are relatively abundant and are important components of
epilithic and epiphytic communities. These are also present, although
usually less abundant, in benthic algal cotntnunities in the least disturbed
areas of the upper lakes. Some apparently more sensitive species such as
C. bremhii , C. laevis , and C. lunata are largely restricted to such areas.
Perhaps the most curious pattern of distribution in the genus is that of
C. triangulum . This large and coarse—walled species is fairly abundant in
epipelic communities growing on sand substrates at depths of 10 m and below
in Lake Superior. Cells are also commonly found in the plankton. The
factors responsible for this highly atypical pattern of occurrence are not
presently known.
We noted only two members of the genus Denticula in our collections.
The most common is D. tenuis var. crassula which is widely distributed in
areas which have not been extensively modified. It is rare or lacking in
areas which have been appreciably eutrophied. The distribution of D. tenuis
is much more restricted. It has only been found in the least disturbed
habitats sampled.
Most members of the genus Diatoma occupy the opposite end of the
spectrum of conditions. Diatoma tenue and its varieties and D. ehrenbergii
are characteristic of regions receiving heavy nutrient and conservative ion
loadings. High abundance of D. vulgare and its varieties is usually
indicative of eutrophic conditions, although it appears less tolerant of
salinification than D. tenue and is also found tn less disturbed areas.
Most members of the genus Epithemia are epiphytes on aquatic vascular
plants and some of the coarser species of fitanientous algae. Most species
also appear to be intolerant of high levels of physical turbulence and are
usually most abundant in small ponds or other protected waters. As might be
19
-------
expected, members of the genus are not generally abundant in communities
occupying shoreline habitats in the upper Great Lakes. A fair diversity of
species is found associated with algal communities at depth. Most of these
species are usually found in oligotrophic areas and some of the species
occurring in the Great Lakes, such as E. emarginata and B. smithii , were
previously reported from fossil localities. The only species which is common
in eutrophied areas is B. sorex , which is occasionally found in dense
Cladophora mats.
Many of the species of the genus Fragilaria which are common in benthic
communities can also occupy the plankton with greater or lesser degrees of
success. In the Great Lakes high abundance of F. capucina in phytoplankton
collections is usually associated with eutrophication. This species is
somewhat more widely distributed in benthic communities. It and species such
as F. brevistriata and F. construens are often important elements of
Cladophora associations, although the latter species are also found in areas
which have not been severely eutrophied. These species are most common in
periphyton communities. Other species, such as F. pinnata and
F. leptostauron , are usually epipelic. Of the two, F. pinnata is apparently
more tolerant of eutrophication and more commonly found in plankton
collections. Fragilaria leptostauron occurs most abundantly in oligotrophic
habitats and its range is similar to that of F. vaucheriae var. capitellata ,
a primarily periphytic taxon. Species such as F. constricta fo. stricta ,
F. lapponica , and F. virescens are restricted to the most oligotrophic
habitats sampled.
Members of the genus Frustulia are relatively rare in benthic
communities occurring in the Great Lakes. Of the species present,
F. vulgaris is the most widely distributed, followed by F. rhomboides var.
amphipleuroides . Occasional specimens of these taxa were noted in
collections from all of the lakes. Other members of the F. rhomboides
complex are more restricted in distribution and more characteristic of highly
oligotrophic habitats. Specimens of F. weinholdii were found only in
historic collections from the Chicago region in Lake Michigan.
Gomphoneis herculeana was originally described from the Great Lakes and
remains an important component of epiphytic and epilithic associations in
relatively undisturbed regions of the system. Occasional specimens were
found in disturbed areas, particularly during the winter months, but it is
never an important element of assemblages in eutrophic areas. The range of
G. eriense is much more restricted, and the few examples found in our study
all came from Green Bay of Lake Michigan.
Members of the genus Gomphonema are abundant in epilithic and epiphytic
communities in the upper Great Lakes. Some of the common eurytopic species
are very widely distributed throughout the system. Species such as
C. angustatum , C. intricatum var. pumila , and G. olivaceum are much more
abundant in eutrophied areas, although occasional specimens are found in
collections from undisturbed areas. In our collections G. parvulum , which is
often cited as an indicator of degraded water quality, was quite abundant in
areas which were not significantly disturbed. The range of certain species
such as C. intricatum , C. manubrim , C. olivaceoides , and C. sphaerophorum was
20
-------
more restricted and large populations of these species are characteristic of
less disturbed habitats. Species such as G. helveticum , G. quadripunctatum ,
and C. subtile are characteristic of the most oligotrophic parts of the upper
Great Lakes and populations were not found in disturbed areas.
Most members of the genus Gyrosigma are relatively large cells and most
freshwater species are adapted to epipelic habitats. Like many other members
of epipelic associations, they are commonly entrained into the plankton and
occasional specimens are routinely noted in nearshore plankton collections
from the upper lakes. Most of the species noted in our collections are more
abundant in Lake Michigan than in either Lake Huron or Lake Superior. This
is probably indicative of both a preference for more eutrophic conditions and
the greater availability of suitable habitat in the Lake Michigan system.
Hannea arcus is characteristic of highly oligotrophic systems and is a
dominant element of periphyton floras in the most oligotrophic large lakes of
the world, such as Lake Baikal. It is present, but relatively rare, in the
least disturbed regions of Lake Michigan and Lake Huron, but is abundant in
some localities in Lake Superior.
In terms of the number of taxa present, Navicula is by far the largest
genus represented in our collections. A number of the more abundant species
are widely distributed throughout the system and apparently eurytopic. There
are, however, a number of species with restricted distribution patterns which
appear to be indicative of varying levels of eutrophication and disturbance.
Species restricted to highly modified i egions near major sources of nutrients
and other pollutants include N. circumtexta , N. citrus , N. confervacea ,
N. integra , N. luzonensis , N. miniscula , N. pygmaea , N. quadripartita , and
N. salinarum . All of these taxa are tolerant of highly eutrophic conditions
and conservative ion contamination. A number of other species including
N. costulata , N. cryptocephala var. intermedia , N. explanata , N. gregaria ,
N. latens , N. odiosa , N. protracta and its varieties, and N. viridula var.
linearis are characteristic of disturbed, but less extreme conditions. A
number of species are apparently restricted to areas which have received
relatively little disturbance. Included in this group are taxa such as
N. bacillum , N. bryophila , N. cocconeiformis , N. farta , N. fracta ,
N. jaernfeltii , N. ordinaria , N. pseudoscutiformisu and N. semenoides . A
surprisingly large number of taxa are restricted to only the most
oligotrophic habitats sampled. Included in this group are species such as
N. aboensis , N. americana , N. contenta , N. globosa , N. gysingensis ,
N. levanderi , N. subtilissma , N. tecta , and N. tridentula .
Members of the genus Neidium are generally rare in benthic algal
communities in the upper Great Lakes. None of the species present are
particularly associated with highly disturbed areas. The most common and
widely distributed species are N. dubium and N. iridis which are found in
many localities throughout the system. A number of taxa including
N. bisulcata , N. calvum , N. hitchcockii , and N. temperi are restricted to
Teast disturbed localities. The pattern of occurrence of
N. distincte—punctatum and N. koziowi is unusual in that, in the Great Lakes,
they are almost entirely restricted to deep—living epipelic communities.
21
-------
The genus Nitzschia is often regarded as an indicator of pollution
because of the extreme abundance of certain species in sites receiving high
nutrient and organic loadings. Like most other genera, however, it contains
species which have habitat preferences spanning the range of conditions found
in the upper Great Lakes. Certain species such as N. apiculata ,
N. filiformis , and N. tryblionella and its varieties are largely restricted
to highly disturbed regions. Others such as N. bulnheimiana , N. sublinearis ,
and N. capitellata occur most abundantly in regions which have been
eutrophied. These regions also usually have greater abundance of some of the
common eurytopic species which are widely distributed throughout the lakes.
A number of species are more characteristic of oligotrophic regions.
Included in this group are species such as N. angustata var. acuta ,
N. denticula , and N. sinuata var. tabellaria .
Although there are a relatively large number of species present, members
of the genus Pinnularia usually constitute a very minor component of benthic
algal assemblages in the upper Great Lakes. As discussed earlier, many of
the species in the genus are most abundant in highly oligotrophic
environments. Many of these populations are restricted entirely to Lake
Superior. None of the species in this genus appear to be particularly
associated with eutrophic conditions, although some, such as P. brebissonli
and P. vlridis , are widely distributed and apparently tolerant of a
considerable range of conditions.
Members of the genus Rhopalodia are similar in growth habitat to members
of the genus Epithemia . Although suitable habitats are not widely available,
Rhopalodia gibba is found in greater or lesser abundance throughout the upper
Great Lakes. The next most abundant species, R. gibberula , is considerably
less widely distributed and appears to be restricted to areas which have
elevated levels of dissolved solids. The opposite tendency is found in
R. parallela , which was only found in collections from highly oligotrophic
habitats.
The ecological affinities and distribution patterns of members of the
genus Stauronels are quite similar to those of members of the genus
Pinnularia. Certain species such as S. acutiscula and S. phoenicenteron are
widely distributed, although rarely very abundant throughout the system. The
majority appear to be restricted to regions which have not been significantly
disturbed. One of the most characteristic species is S. dilatata , which has
not been widely reported from North Mierica except in the Great Lakes
(Stoermer 1978).
The genus Stenopterobia is largely restricted to ultraoligotrophic or
dystrophic environments. The only species noted in our collections,
S. intermedia , was only found in collections from Lake Superior.
Surirella Is a relatively large and complex genus, containing many
apparently endemic genera. Many of the species in the genus have very large
cells and the majority are adapted to epipelic habitats. Many of them are
found, usually in low abundance, in plankton collections. They can
apparently survive extended entrainment in the plankton and may constitute a
significant portion of the biovolume of phytoplankton assemblages because of
22
-------
the large size of individual cells. The genus contains a large number of
morphological types, and these are, to some extent, characteristic of certain
ecological affinities. In the Great Lakes, S. delicatissima is
representative of a number of species which have some morphological
similarities to members of the genus Stenopterobia . Like Stenopterobia they
tend to be restricted to very oligotrophic environments. In our collections
S. delicatissima was noted only in collections from undisturbed habitats in
Lake Huron and Lake Superior. The opposite extreme is represented by species
such as S. ovalis and the S. ovata complex. These species are tolerant of
eutrophic conditions and are most abundant in waters with elevated levels of
total dissolved solids. These species, together with S. angusta which is
somewhat more widely distributed, are characteristic of epipelic communities
in Saginaw Bay of Lake Huron and lower Green Bay in Lake Michigan. They are
also occasionally abundant in plankton collections from these areas, and
occasional specimens are found in nearshore plankton collections taken in the
vicinity of larger rivers in Lake Michigan. Most other species in the genus
are relatively rare and their distribution patterns are not completely known.
Members of the genus Synedra are important components of periphyton
communities in the upper Great Lakes. Many of the species present are widely
distributed and apparently eurytopic, but some have well defined occurrence
patterns. As discussed earlier, S. fasciculata and S. pulchella are
restricted to areas receiving gross conservative ion contamination. Species
such as S. tenera , S. ulna var. amphirhynchus , S. ulna var. oxyrhynchus , and
S. vaucheriae var. capitellata are characteristic of rich periphyton
associations found in relatively indisturbed areas. They are apparently
tolerant of moderate nutrient loadings, but are displaced from communities in
areas which receive heavy loadings. This genus also contains a large number
of morphological entities which cannot be identified with known species.
Most of these are most common in oligotrophic habitats.
23
-------
REFERENCES
Beeton, A.M. and D.C. Chandler. 1966. The St. Lawrence Great Lakes,
p. 535—537. In: Frey, D.C. (ed.) Limnology in North America. Univ.
Wise. Press, 734 pp.
Briggs, S.A. 1972. The diatomaceae of Lake Michigan. The Lens, 1: 41—44.
Hutchinson, G.E. 1967. A treatise on limnology. Vol. II. An introduction
to lake biology and the lininoplankton. John Wiley and Sons, New York,
1115 pp.
Kishler, J. and C.E. Taft. 1970. Bangia atropurpurea (Roth) A. in western
Lake Erie. Ohio J. Sci., 70(l): 56—67.
Kreis, R.G., Jr. and E.F. Stoermer. 1979. Diatoms of the Laurentian Great
Lakes. III. Rare and poorly known species of Achnanthes Bory and
Cocconeis Ehr. (Bacillariophyta). J. Great Lakes Res., Internat. Assoc.
Great Lakes Res., 5(3—4): 276—291.
Patrick, R. and C.W. Reimer. 1966. The diatoms of the United States
exclusive of Alaska and Hawaii. Vol. 1. Fragilariaceae, Eunotiaceae,
Achnanthaeeae and Naviculaceae. Acad. Nat. Sci., Phila., Mongr. 13,
688 pp.
Scheiske, C.L., E.F. Stoermer, J.E. Gannon and M.S. Simmons. 1976.
Biological, chemical and physical relationships in the Straits of
Mackinac. Univ. Mich., Great Lakes Res. Div., Spec. Rept. 61, 267 pp.
Stevenson, RJ. and E.F. Stoermer. 1978. Diatoms from the Great Lakes. II.
Some rare or poorly known species of the genus Navicula . 3. Great Lakes
Res., Internat. Assoc. Great Lakes Res., 4(2): 178—185.
Stoeroier, E.F. and J.J. Yang. 1971. Contribution to the diato 1 n flora of the
Laurentian Great Lakes. I. New and little—known species of Amphora
(Bacillariophyta Pennatibacillariophyceae). Phycologia, 10(4): 397—409.
• 1975. Comparison of benthic diatom communities in Lake
Michigan and Lake Superior. Verh. Internat. Verein. Limnol.,
19: 923—938.
• 1977. Post—pleistocene diatom succession in Douglas Lake,
Michigan. J. Phycol., 13(1): 73—80.
24
-------
________ and R.G. K.reis, Jr. 1978. Preliminary checklist of diatoms
(Bacillariophyta) from the Laurentian Great Lakes. J. Great Lakes Res.,
Internat. Assoc. Great Lakes Res., 4(2): 149—169.
________ 1978. Diatoms from the Great Lakes. I. Rare or poorly
known species of the genera Diploneis, Oestrupia and Stauroneis . J.
Great Lakes Res., Internat. Assoc. Great Lakes Res., 4(2): 170—177.
Thomas, B.W. and H.H. Chase. 1887. Diatotnaceae of Lake Michigan as
collected during the last sixteen years from the water supply of the
city of Chicago. Notarisia, 2(6): 328—330.
Thompson, H.D. 1896. Report on the plants, p. 72—75. In: Ward, H.B.
A Biological examination of Lake Michigan in the Traverse Bay region.
Bull. Mich. Fish. Comm., 6: 1—71.
Wujek, D.E. and M.L. Welling. (in press). Phytoplankton and water chemistry
from three water intakes in Michigan nearshore waters of Lake Michigan,
February, 1978 to January, 1979. Rept. to the Mich. Dept. Nat. Res.
25
-------
TABLE 1. SUMMARY OF BENTHIC DIATOM POPULATION DISTRIBUTION IN THE UPPER GREAT LAKES
Name
ACHNANTHES
Lake Michigan
1 II III
Lake Huran
I II III
Lake Superior Primary Secondary Depth
L_IL IL habitats ra
Notes
Achnanthea affini8
1)
A
R
A
A
R
A
A
R
R, sS
P
Sp-D
Widely Distributed
Achnanthes anoena oust.
R
0
0
0
0
0
0
0
C)
R
-
0
Rare, Boreal
A hnanthes ataco,mae Oust.
-
R
-
-
P.
-
-
-
-
SSa
Ra
I
Achnanthee bia8olettiana (KCItz) (Irun.
C
P.
V
C
P.
V
C
C
-
SSa
Ra
Sp-l)
Oligotrophic
Achnanthe8 bioreti Germain
P.
P.
V
P.
P.
V
P.
P.
-
SSa
Ra-PEa
Sp-l
Eurytopic
Achnanthee caloar Cl.
P.
0
0
P.
P.
0
C
P.
0
SSa
Ra
Sp-I
Oligotrophic
Aohnanthee clevei Grun.
C
C
N
C
C
C
C
C
C
SSa
Ra, 1
1-0
Eurytopic
Achnanthea clevei var. roatrata Oust.
C
C
P.
C
C
C
P.
P.
V
SSa
P.a, 1
1-0
Occasionally on plankton
Achnanthee coarctata (Br h..) Grun.
Achnanthee conspioua A. Mayer
0
P.
0
C
0
C
0
P.
0
R
0
C
V
V
0
V
0
P.
Ra
SSa
-
Ra
Sp
Sp-l
Aerophytic, Allochthonous
Eutrophic
Achnanthe8 conspicua var. brevjstriata Oust.
0
V
0
0
0
0
0
0
0
SSa
-
I
Achnanthea deflexaReim.
C
P.
V
C
C
-
C
C
-
Ra, SSa
PPa
Sp- [ )
Distribution poorly known
Achnanthee delicatula (K itzjGrun.
0
0
V
0
0
0
0
0
0
SSa
-
I
lalophilic (7)
Achnanthes detha Hoho and Helleru.
V
P.
v
o
o
o
o
o
o
S
-
I
Distribution poorly known
Achnanthes didyma lust.
0
0
0
V
0
0
P.
P.
o
SSa
-
Sp
Rare, Boreal
Achnanthea disparCl.
C)
V
P.
V
1)
0
C)
0
0
SSa
-
I
Boreal, Halophilic (?)
Achnanthea duthii Srean.
P.
0
0
C
P.
0
C
C
0
PP, P.
-
Sp-l
Distribution poorly known
Achnanthes exiguaGrun.
P.
P.
C
P.
P.
C
V
P.
P.
Pa, SSa
Ph
Sp-l
Widely distributed
Achnanthea exigua var. constricta orka
P.
P.
C
P.
P.
R
V
V
V
Ra, SSa
Ph
Sp-1
4c,rn.anthea exiguavar. eterovalva Krasske
R
P.
C
P.
P.
R
V
V
V
Ra, SSa
Pb
Sp-I
Eurytopic
Achnanthes exigua var. heterovalva
fo. serniaperta Guer.
Achnanthe8 flexella (Kiitz.) Brun
P.
C
0
P.
0
V
P.
C
0
P.
0
V
P
I)
P.
A
0
V
SSa
SSa
Pa
Ra
Sp-1
Sp-l
Distribution poorly known
Borea), Oligotrophic
(continued)
-------
Lake Michigan Lake Huron Lake Superior Primary Secondary Depth
I II III I II III I II III habitats habitats range Notes
Name
TABLE 1 (continued)
Achnanthes gracillima Hust.
0
0
0
0
0
0
V
0
0
?
T
Distribution pooriv known
Achnanthes hauckiana Grun.
0
V
R
0
0
0
0
0
0
SSa
I
Sp-I
Halophilic (?)
Achnanthee hauckiana var. rostrata Schulz
Achnanthes hungarica (Grun.) Grun.
0
0
V
0
R
R
0
a
0
o
0
V
0
0
0
0
0
0
SSa
PV
T
r
Sp-I
Sp
More abundant than nomi-
nate variety
Probably allochthonous
Achnanthe8 kryophila Peters.
0
0
0
0
0
0
R
V
0
SSa
Ra
Sp-J
Boreal, oligotrophic
Aohnanthes kryophila var. africana Choin.
0
0
0
0
0
0
C
P
0
SSa
Pa
Sp-I
Distribution poorly known
Achnanthes lanceolata (Brtb.) Grun.
Achnanthes lanceolata var. abbreviata Reim.
P
R
R
P
C
C
P
R
R
P
P
R
R
V
R
0
P
0
SSa
SSa
Pa
Ra
Sp-D
Sp-I
Eurytopic, widely distri-
buted
Distribution poorly known
Achnanthes lanceolata var. apiculLata Patr.
0
0
R
0
0
0
0
0
0
SSa
Ra
Sp
‘
Achnanthes lanceolata var. dubia Grun.
Achnanthee lanceolata var. haynaldii
(Schaarsch.) Cl.
Achnanthes lanceolata var. omissa Reim.
P
0
P
P
0
R
C
V
C
P
0
P
P
0
R
C
0
P
P
V
V
P
0
V
R
0
P
SSa
SSa
SSa
Pa
Pa
Sp-I
Sp
Sp-l
Eurytopic
Distribution poorly known
,.
Achnanthes lanceolatoides Soy.
Achnanthes lapponica (Hust.) FIust.
Achnanthes laterostrata Hust.
0
0
V
V
V
0
0
0
0
0
0
P
0
0
V
0
0
0
0
0
P
0
0
P
0
0
0
SSa
I
SSa
-
Pa
I
-
Sp-I
Very rare, apparently
oligotrophic
Known only from historic
samples
Boreal
A,ah1 2fltha8 lauenburgiana Hust.
V
P
P
0
V
V
0
0
0
SSa
T
I
Distribution poorly known
Achnanthee lerrgner,nannj Hust.
0
P
P
0
0
0
0
0
0
?
-
I
Perhaps allochthonous
Achnanthes levanderi Hust.
V
0
0
P
0
0
C;
K
-
SSa
Pa
Sp-I
Boreal, oligotrophic
Achnanthec linearis (W. Sm.) Grun.
Achnanthes linearis fo. ourta H.L. Sm.
C
P
C
R
P
R
P
0
P
0
K
0
P
0
P
0
K
0
SSa
SSa
Pa
-
!-D
I
More abundant in
historic samples
Achnanthes rnarginulata Grun.
P
0
0
K
P
0
R
P
0
SSa
Pa
Sp-I
Oligotrophic, Roreal
Achnanthes microcephala (KUtz.) Grun.
C
P
R
C
P
P
C
c
-
PPa
SSa
Sp-l
Achnanthes rninutissirsa Ktltz.
C
K
1)
C
R
I)
C
K
[ ‘Pa
Pa
Sp-I
Widely distributed
(continued)
-------
TABLE 1. (continued)
Name
Lake Michigan Lake Huron Lake Superior Primary Secondary Depth
I II III I II I I I - I II III habitats habitats ran 1 _
R R V C P V A C P PPa Pa Sn-I
Notes
Achnanthee minutia8ima
var. cryptocephala Grun.
Achnanthea oeetrupi (A.Cl.) Hust.
C
V
V
P
V
0
C
P
P
SSa
Pa
D-Sp
Boreal
Achnanthee oeetrupi var. lanceolata Hust.
R
0
0
R
0
0
P
P
0
SSa
Pa
D-Sp
Achnanthea peragalli Brun and Ii tib.
P
V
0
R
V
0
P
P
0
SSa
Ra
D-Sp
Boreal
Achnanthea pinnata Hust.
Aahnanthea pioertenave Hust.
R
0
C
V
A
0
0
0
V
0
P
0
0
0
0
0
0
0
SSa
SSa
Ra
-
I-I)
I
Distribution poorly known,
apparently eutrophic
Aohnanthea procera Hust.
V
0
0
0
0
0
R
R
0
SSa
Ra
Sp-I
Achnanthee aubtaevie Hust.
V
0
0
V
0
0
R
P
0
SSa
Pa
Sp-I
Boreal
Achnanthee eub aloi4ea Hust.
0
0
0
0
0
0
P
R
0
SSa
Pa
Sp-I
Achnanthee euchlandtj Hust.
V
0
0
0
0
0
R
R
0
SSa
Ra
Sp-I
F’ .
AMPHIPLEURA
Anrphipleu.ra aratica Patr. and Freese
Amphipleura pellucida (KUtz,) KUtz.
V
C
R
C
P
A
0
C
V
C
0
A
0
R
0
R
0
C
SSv
SSv
I
I
1-0
Sp-I
Most abundant in older
samples
Widely distributed
AMPHORA
Amphora bullatoideB Hohn and Hellerm.
0
R
p
o
0
o
o
0
0
SSa
Ra
1-0
Distribution poorly known
Amphora calumetica (Thomas) M. Perag.
C
C
P
C
C
Il
V
0
0
SSa
Ra
1-0
Apparent endemic
Amphora cruoiferoides Stoerm. and Yang
.
Amphora fontvcoia Maill.
V
V
R
V
P
V
0
V
0
0
V
0
0
0
0
0
0
0
SSa
SSa
Ra
Ra
0-I
0 —I
Recently described, apparent
endemic
Amphora hemicycla Stoerm. and Yang
V
R
R
0
V
V
0
0
0
SSa
Ra
0-I
Recently described
Amphora huronenaie Stoerm. and Yang
V
V
0
V
V
0
0
0
0
SSa
Ra
0-I
Recently described
Amphora michiganen8ia Stoerm. and Yang
Amphora montana Krasske
A
0
C
0
R
R
R
0
R
0
V
0
V
0
V
0
0
0
SSa
Ra
Pa
PP
0-I
Sp
Recently described, also in
small lakes of the region
Widely distributed, eutrophic
Amphora negleota Stoerm. and Yang
V
R
R
V
R
R
0
0
0
SSa
Ra
0-I
Recently described
Amphora normanii Rabh.
0
0
V
0
0
0
0
0
ORa
I
allochthonous
(continued)
-------
TABLE 1 (continued)
Name
Amphora ovalio (KUtz.) KUtz.
Amphora ovalis var. conatricta Sky.
Amphora ovali8 var. gracilia (Ehr.) V.H.
Anphora ovalia var. libyoa (Ehr.) Cl.
Amphora ovali8 var. pedicuiu8 (KUtz.) V.H.
Amphora perpuajila (Grun.) Grun.
Amphora rotunda Sky.
Amphora aibirica Sky, and Meyer
Amphora BUbco8tulata Stoerm. and Yang
Amphora veneta XUtz.
t Amphora veneta var. capitata Haworth
ANOMOEONEIS
Anomoeoneia co8tata (KUtz.) Ilust.
Anomoeonejo follj8 (Ehr.) Cl.
Anomoeoneia Banana var. brachysira
(Br b.) Hust.
Anomoeoneie etyniaca (Grun.) Huat
Anomoeoneja vitrea (Grun.) Ross
Anomoeoneia aellenai (Grun.) Cl.
BACILL.4RIA
C D IJ C C C R R C SSa Ra
P 0 0 R 0 0 R 0 0
0 R 0 0 0 0 V 0 0
R R P P P R R R R
C D A C A C R R C
C A A C A A P P P
0 0 R 0 0 0 0 0 0
R R R 00 0 0 0 0
R R R P R 0 V 0 0
R C P 0 0 0 0 0 0
R P V V V 0 R R V
o V V 0 0 0 0 0 0
0 0 0 V 0 0 V 0 0
0 0 0 0 0 0 V V 0
V 0 0 V 0 0 V 0 0
P V V C R 0 A C V
V 0 0 0 0 0 0 0 0
I-D Widely distributed
Distribution poorly known
Widely distributed
Widely distributed
Distribution poorly known
Most common in historic
samples
Recently described
Eutrophic
Most reports from fossil
localities
Sp Halophilic, p rhaps
al lochthonous
Dystrophic
SP Oligotrophic-dystrophic
SP-I
Sp
Bacillaria paxillifer (0. F. Mull.) Hendy
CALOiVEIS
0 V V 0 0 V 0 0 0
SSv
Sp Halophilic
Caloneja alpeatnia (Grun,) Cl.
Caloneia ojnphiabaena (Bory) Cl.
C R V C V 0 P R 0
0 0 R 0 0 P 0 0 0
SF SS Sp -I
SF SS Sp-I Halophilic
Lake Michigan Lake Huron Lake Superior Primary Secondary Depth
I II III I II III I II III habitats habitats range
Notes
I-D
I-D
I-D
I-u
I-D
9
I-D
I-D
S
Sp-I
SSa
SSa
SSa
SSa
SSa
9
SSa
SSa
SSa
SSa
SF
SF
SF
SF
SF
SF
Pa
Pa
Ra
Pa
Ra
9
Ra
Ra
Pa
Ra
SS
SS
SS
SS
(continued)
-------
CAMPYLODISCUS
TABLE 1 (continued)
SS
SS
SS
SS
Ss
SS
sS
Ss
SS
Ccvirpylodiaoua noric u var. hibernica
(Ehr.) Grun.
V 0 0 V 0 0 0 0 0
SF SS
I-D
CAPARTOGR4J&4A
Capartogr ra cru icula (Grun.) Ross
COCCOMEIS
o 0 V 0 0 V 0 0 0
CA C CC C C C R
R R R R R R R R R
A A 0 A A D R R C
R R R P P R R P R
C C D C C 9 P C C
C C P C C P D C C
o 0 0 0 0 0 0 0 0
SF S-I Halophilic
SSa D-I
SSa I-D
- S-I
PP S-D
SSa S-D
SSa 5-0
Lake
Name I
Caloneje baciliaria var. ther najia (Grun.) P
A.C1.
Caion ia ba iilum (Grun.) Cl. R
II
V
R
Michigan
III
V
V
Lake Huron
I II III
P V V
R P V
Lake
I
V
R
II
V
R
III
0
V
Primary
habitats
SF
SF
Secondary
habitats
SS
Depth
range
Sp-I
Calongia baoiliwn var. ic moettuia
(Schulz) Hust.
Caloneia oievei (Lagerst.) Cl.
P
0
R
V
V
0
P P V
0 0 0
R
V
V
0
V
0
SF
SF
Caioneia lewtajj Patr.
V
V
0
0 0 0
V
o
0
SF
Caioneiø iu’noaa (KUtz.) Patr.
V
V
0
0 0 0
V
V
0
SF
Caioneia nubiooia (Grun.) Cl.
0
0
0
0 0 0
V
0
0
SF
Calonaia uentricoea (Ehr.) Meist.
V
0
0
V 0 0
V
0
0
SF
Caioneia ventriooaa var. minuta (Grun.) 0
Patr.
Cajoneja ventriooaa var. truricatula R
(Grun.) Meist.
V
V
0
0
0 0 0
P V 0
0
P
0
R
0
0
SF
SF
Notes
0
Sp-I Widely distributed
Sp- I
Sp-I l)istribution poorly known
Sp Generally rare
Sp—l
Sp-l
Sp-I
Sp-I
Sp-I
Cooconeja diminuta Pant.
Cooconeia diaculua (Schwa.) Cl.
Cocconeja pediculue Ehr.
Cocconeia piacentula Ehr.
Cocconeia pZ .acentuia var. euglypta
(Ehr.) Grun.
Cooaoneia piacentula var. lineata
(Ehr.) V. H.
Cocooneia piacentula var. rou ii
(Hérib. and Brun Cl.
SS
Pa
Pa
PP
Ra
Pa
Ra
Pa
Common on Cladophora sp.
01 igotrophic
(continued)
-------
TABLE 1 (continued)
Lake Michigan Lake Huron Lake Superior Primary Secondary Depth
Name I II III I II III I II 111 habitats habitats range Notes
CYMATOPLEL/RA
Cymatopleura cochlea J. Brun
Cymatopleura elliptica (Br b. and Godey)
W. Sm.
Cymatopleura solea (Bréb. and Godey) N. Sm.
Cymatopleura solea var. apioulata (W. Sm.)
Raif a
Cymatopleura 8olea var. clavata 0. MUll.
Cymatopl.eura solea var. regula (Ehr.) Grun.
CYMBELLA
V R
V R
R R
V R
o v
o V
P 0 0
R 0 0
R V V
P 0 V
P 0 V
R V P
R V R
o 0 0
o 0 0
o SF I
o SF I
V SF I
0 0 V SF
P
0
0
o 0
o 0
o SF
o SF
V 0
R R
V 0
V 0
V 0
V V
o o
o o
P R
A P
C P
P 0
P V
o ss
o ss
o SS
O SF
O SF
I More common in historic
samples
I I
I I
I I Only found in historic
samples
- I Probably allochthonous
Pa I
R I
P I
P I
P Sp-I
- Sp
- 1-0
SS Sp-I
PPa S-I
ppa S-I
PPa S-I
PPa S-I
O V 0
O 0 0
O V 0
O V 0
O 0 0
O 0 0
V R P
P A P
O C P
O 0 0
V P V
Cymbella acutiuscula Cl.
0
0
V
0
0
0
0
0
0
SS?
Eurytopic
Cymbell.a aequalie N. Sm.
0
0
0
0
0
0
0
SS?
Cymbella affinie KUtz.
P
P
R
P
P
P
P
pp
Cymbella amphicephalLa Mug.
Cymbella ønphicephala var. subundulata
Cl.
Cytnbella anguatata (N. Sm.) Cl.
Cymbelia aspera (Ehr.) H. Perag.
Only old L. Michigan
samples
Cymbeila aspera var. minor (V.H.) Cl.
Cymbelia brehmii Hust.
Cymbelia cesatii (Rabh.) Grun.
Cymbeila ciatula (Ehr.) Kirchn.
Widely distributed
Cymbeila cistula var. gibbosa Brun
Oligotrophic
Cymbeila cistula var. truncata J. Brun
C’ymbe lie cuspidata KUtz.
Cymbella cuspidata var. schuizii A. Cl.
V
0
0
0
0
0
P
0
0
SF
Sp-1
Cymbeila delicatula KUtz.
C
P
V
C
P
VA
C
V
S -
Sp-I
Boreal, oligotrophic
O V 0
O 0 0
O P 0
O P 0
O V 0
O C 0
O A C
P A C
O C C
O C 0
O P 0
0
P
R
0
0
0
Pa
SF
Pa
Pa
Pa
Pa
(continued)
-------
TABLE 1 (continued)
Name
CymbeUa huatedtii krasske
Cymbeila hybrida Grun.
Cymbeila inaequatia (Ehr.) Rabh.
Cymbeila incerta (Grun.) Cl.
Cymbella lczeoia Nag.
Cymbeila lanceolata (Ag.) Ag.
Cymbella iota Grun.
Cymbelia iatena Krasske
Cymbelia ieptooeroe (Ehr.) KUtz.
Cymbelia leptoceroa var. roatrata Hust.
Cymbelia lunata W. Sm.
Cymbeila me rioana (Ehr.) Cl.
Cymbelia microoephaia Grun. A C
Cymbeila minutcz Hilse R P
Cymbeila ni l nuta var. p8eudograciiia R V
(Choin.) Reim.
Cymbeila minuta var. sile8taca (Bleisch) Reim 0 0
PPa
P, P
S
S
S
Sp-I Widely distributed
Sp-I Widely distributed
Sp- I
Sp
Sp—I More common in historic
samples
Sp- I
SP- I
Sp- I
Sp-I
S.-’
Lake Huron Lake Superior Primary Secondary Depth
I II III I II II I habitats habitats
Lake Michigan
I II III
A C P A C
P R 0 R R
V 0 0 00
V 0 0 00
P 0 0 C P
P0 0 P0
V V 0 0 0
C C R C C
R 0 0 R 0
R V 0 R 0
0 0 0 0 0
Notes
P C P
V K R
o 0 0
o 0 0
0 A C
o R 0
o 0 0
V A C
0 R 0
o R V
0 R 0
0 S
O S
O S
0 S
0 S
0 PVa
0 Pa
P S
o Pa
V SS
o ss
P 1- 1)
- I-D
- 1-0
- Sp-1
Pa Sp-I
PPa I
P Sp-I
PPa I
K Sp-I
K Sp
R V V R V V P V V Pa
Cy inbeil -a muel ieri Hust. P 0
Cymbelia muelieri fo. ventricoea (Temp. and 0 0
Perag.) Reim.
Cymbeila naci .ouiifoimnie Auersw. P 0
Cymbeilo norvegica Grun. P P
Cyinbeila obtusiu ouia KUtZ. p p
C ymbeiia parva (W. Sm.) Cl. V V
Cymbelia parvula Krasske V V
C A C
P R P
0 R 0
0 00
0 P V
0 00
0 R 0
o R 0
0 P V
o o V
V V V
C C C C S
R V P R PP
o R V 0 PP
o v 0 0 PP
0 P V 0 S
0 P 0 0 P
o 0 0 S
0 0 0 0 S
0 P V U S
0 V V 0 S
0 V V 0 S
P
P
P
More common in historic
samples
(continued)
-------
TABLE 1 (continued)
Cyrnbella prostrata (Berk.) Cl. R C
Cymbella proatrata var. auer8waldii (Rabh.) R c
Reim.
Cymbella proxima Reim. R v
Cymbella sinuata Greg. c R
Cymbella sinuata var. antiqua (Grun.) Cl. v o
Cyrnbella sinuata fo. ovata (Ilust.) Hust. v 0
Cymbella subaequali8 Grun. 0 0
Cymbella subventricosa Choin. v o
Cymbell.a triangulum (Ehr.) Cl. K V
Cymbella tumida (Bréb.) V.11. V V
Cymbella tumidu? .a Grun. a o
CYMBELLONITZSCIJIA
Cymballonitzsahia diluviana Hust. 0 o
Denticula tenuis KGtz.
Denticula tenut8 var. crassula (Nag.)
W. and G.S. West
DIATOMA
R R P
o R V
V C R
o v 0
o v 0
o o 0
o R 0
o R R
V 0 V
V 0 0
V 0 0 0 V 0 0 S S
Ns*
Lake Michigan Lake Huron Lake Superior
I II III I II III I 11 III
Priiiary Secondary Depth
_____________ _____________ habitats habitats range Notes
C P R c V R c pp s S-I Common in C1yg a
communities
R R P P PP S S-I
o R V o PP s I-S
V V P V S P Sp-D
o C P 0 S P Sp-D
o V 0 0 S - Sp-D
o V 0 0 S - Sp
O A P 0 S PP Sp
O R R V S T 1—0 Often found in L. Superior
plankton.
V V V V PP P
O 0 0 0 P. — S
DFJNTICUL.4
C 0 0 R
D A R S
O 0
A C
O 0
O V
v g
O 0
V 0
P C
Diatoma ancepa (Ehr.) Kirchn.
Diatoma anoepe var. linearis M. Perag.
Diatoina ehrenbergii Kilts.
Diatoma hiejnale (Roth) Heib.
Diatama hiemale var. mesodon (Ehr.) Grun.
Diatoma tenue Ag.
O 0 0 0
V A C V
O 0 0 0
O 0 0 0
C 0 0 R
O 0 0 0
O 0 0 0
C V R R
S
R
A
S
S
S
T
K 0
O 0
O 0
V 0
V 0
V V
O K
O R
O R
O R
O R
C R
I-D
I-a
Sp
I Probably allochthonous
S—I Halophilic
Sp
Sp
Sp—I Common in plankton
(continued)
-------
DIDYMOSPHAFJNIA
TABLE 1 (contInued)
DIPLONEIS
Diploneia boldtio.na Cl.
Dipiorisia dc nbiittonai (Grun.) Cl.
Dipioneia oiiiptioa (KUtz.) Cl.
Dipioneie eliiptioa var. pygmaea A. Cl.
Dipion i finnica (Ehr.) Cl.
Dipioneia obiongelia (N*g.) Rose
D tpionei ocuiata (Bréb.) Cl.
Dipionei8 ovalia (Huge) Cl.
Dipioneia pa via Cl.
Di.piOflBi8 subovaije Cl.
ENTOMONEIS
Ento nonei. ornata (J.W. Bail.) Rejig.
EPITHEMIA
o 0 0
o v o
o 0 0
o ft v
o v v
V 0 ft V
V 0 0 0
o 0 0 0 $
o 0 0 S
o V 0 0 S
o ft ft 0 S
o ft V 0 S
o R V 0 S
o 0 0 0 S
PP S—I Oligotrophic
Sp— I
Sp—I
Sp—I
I
Sp—I Oligotrophic
Sp—I
Sp—I
Sp—I
Sp—I Boreal, oligotrophic
Sp—I
l—D Eurytopic
Epithemia adnata(KUtz.) Br b.
Epithemia advatavar. porceilue
— (Katz..) Patr.
ft ft ft 0 V 0 0 0 0 PP R
V ft V 0 V 0 0 0 0 PP ft
I—D
I—D
Name
Lake
I
ft
II
K
Michigan
III
C
Lake
I
ft
II
K
Huron
III
C
Lake
I
K
Superior
II III
K C
Primary
habitats
Secondary
habitats
i ’ ’
Diatcana vuigare Bory
Diatoma vulgare var.
breve
Grun.
0
ft
K
0
0
0
o
0
0
a
pp
S
Diatorna vuigare var.
grands
(W.
Sm.)
Grun.
0
V
0
0
0
0
0
0
0
R
PP
S
Diatoma vul.gare var.
linearie V. 11.
0
ft
0
0
0
0
Depth
S
Didymoephenia gøninata (Lyngb.) N. Schmidt 0
Notes
0 0
Common in Cladophora conenuniti
ft V 0
ft V 0
R K 0
S
V 0 0
V 0 0
V 0 0
S
V
0
0
V
V
V
0
V
V
ft
V
V
V
More common in old samples from
Lake Michigan
ft R ft 0 ft ft 0 0 0 SSv 1’
(continued)
-------
TABLE 1 (continued)
o 0 0 0 0 0
0 0 0 0 V 0
0 0 0 0 00
0 0 0 0 0 0
ft R R R 0 0
0 ft 0 0 0 0
0 C V 0 V 0
V 0 0 V 0 0
0 ft V 0 ft V
0 V 0 0 V 0
0 0 0 0 V 0
Primary Secondary Depth
habitats habitats
Sp—D
pp Sp—I
ft 1—0
PP Sp—I
0
ft 0—I
0—I
ft 0—I
PP Sp—I
R 0—I
ft D—I
- 0—I
Lake
Michigan
Lake
Huron
Lake
Superior
I
II
I
II
I
II
III
V V V 0 V 0 V 0 0 PP R
E’pithemia adnata var. saxoniccz
(KUta.) Patr.
Epithemia argu8(Ehr.) IUItz.
Epithemia argue var. alpeetris Grun.
Epithemia argue var. longicornie
(Ehr.) Grun.
4 ’ithemia emarginata And revs
Epithemia inter’,nediapricke
Epithesnia reicheltipricke
Epithemia emithii (.arruthers
Epithemia aorexftiltz.
Epithemia turgida(Ehr.) KUtz.
U ’ Epithemia turgidavar. granulata
(Ehr.) Bruit
Epithemia turgidavar. wester,nannii
(Ehr.) Grun.
EUNOTL4
V 0
V V
V 0
V 0
C A
ft 0
K V
0 0
K V
V 0
0 0
0
0
0
0
0
0
0
0
0
0
0
PVa
PP
PV
PP
1 ’1’
t ’i ’
P 1’
PV
PP
PP
K
Previous reports fossil
Distribution poorly known
Eutrophic—possibly allochthonous
L. Michigan historic samples only
Eunotia arcue Ehr.
V
0
0
0
0
0
K
V
0
PP
3
Sp—t
Eunotia arcua var. bidene Grun.
V
0
0
0
0
0
C
V
0
PP
S
Sp-I
Eunotia arcue var. faliA Hust.
V
0
0
3
0
0
K
V
0
PP
S
Sp—I
Eunotia curvata (KLItz.) Lagerat.
V
0
0
0
0
0
ft
V
0
PP
S
Sp—I
Eunotia diodon Ehr.
V
0
0
0
0
0
ft
V
0
PP
S
Sp—.I
Eunotia exigua (Br b.) Rabh.
0
0
0
0
0
0
V
0
0
PP
S
Sp—I
Eunotia flezucea Br b.
V
0
0
C
V
0
C
V
0
PP
S
Sp—I
Eunotia fiexuoea var. eurycephala
Grun.
0
0
0
0
0
0
V
0
0
PP
-
Sp- I
Eunotia formica Ehr.
K
0
0
R
0
0
K
0
0
R
PP
Sp—D
(continued)
-------
TABLE 1 (continued)
Maine
Eunotia inoiga W. Sni.
Eunotia miorooaphala Krasske
A’unotia naegelii Migula
Eunotia pectinalia (0. MUll.) Rabh.
Eunotia pectinalia var. mjno (lWtz.) Rabh.
Eunotia pectinalis Var. uentrvooaa Grun.
Eunotia perpuaiiZd Grun.
Eunotia praerupta Ehr.
EuIIQ iG praarupta var. bidene (Ehr.) Grun.
Eunotia praarupta var. inflata Grun.
a’ Eunotia peeudolunaris Venkt.
Eunotia praar’upta var. l4tvoeps f. ourta
Grun.
Eunatia aeptentriona lie Østr.
Eunotia eerra Ehr.
Etinotia tenella (Grun.) Hust.
Eunotia trinacria Krasake
FJunotia vanheurokii Patr.
Eunotia vanheurckii var. intex,nedia
(Krasake) Patr.
FFAGILARIA
Lake Michigan Lake Huron Lake Superior Primary Secondary
I II III - I II III I II III habitats habitats
V 0 0 0 0 0 A V 0 SS S
o 0 0 0 0 (.1 V 0 0 SS —
o o R 0 0 0 R 0 PP R
o o 0 0 0 0 R 0 0 PP R
o 0 0 0 0 0 V 0 0 S —
o 0 0 0 0 0 V 0 0 S —
o 0 0 0 0 0 V 0 0 S —
R 5 0 5 0 0 5 5 0 5 PP
0 0 0 0 0 0 5 V 0 5 PP
O 0 0 0 0 0 V 0 0 K SS
0 0 0 0 0 0 V 0 0 R PP
0 0 0 0 0 0 R 0 0 R PP
00 0 00 0 50 0 5 —
V 0 0 V 0 0 5 0 0 S —
00 0 00 0 R 0 0 S —
0 0 V 0 0 0 0 0 0 PP —
0 0 V 0 0 0 R V 0 S R
0 0 0 0 0 0 5 0 0 S —
Depth
Notes
Sp—I L. Michigan sample, probably
allochthonous
Sp
Sp—I L. Michigan sample, probably
allochthonous
Sp
Sp
Sp
Sp
Sp—D
Sp
Sp—I
I
1—0
Sp
Sp—I
Sp
Sp Probably allochthonous
Sp—I L. Michigan sample, probably
allochthonous
Sp
Fragilaria breviatriata Grun.
K
C
C
K
R
C
K
R
K
S
I
Sp—I
Fragilaria breviatriata var.
H rib.
capitata
V
0
0
0
0
0
0
0
0
S
T
Sp—I
Fragilaria breviatriata var. inflata
(Pant.) Must.
C
R
V
R
5
0
C
C
0
S
T
Sp1
(continued)
-------
TABLE 1 (continued)
Notes
0
R
V
V
V
R R
00
R V
R V
0 V
R R R
R R R
V C R
V R V
V V V
T
T
T
R S
R S
V S
V S
V S
Plankton dominant in shallow,
eutrophic regions.
Extreme oligotrophic
Great Lakes distribution unusual
Sp—I Common in fossil deposits
Distribution poorly known,
perhaps allochthonous
Lake
Michigan
Lake
Huron
Lake
Superior
Primary
Secondary
Depth
L k’
H A
‘I’
D
1_ LLL’1
R A 0
.LL. X’J
V H A
J Ai
S
T
!
Sp1
Fragilaria capucina Deem.
Fragilo.ria capucina var. mesolepta Rabh.
H
C
A
V H
C
0
0 0
S
T
Fragilaria conetricta to. etricta
0
0
0
0 0
0
V
0 0
S
R
Sp
(A.Cl.) Hust.
Fragilaria conatruena (Ehr.) Grun.
R
C
A
R C
C
A
R D
S
T
Sp 1
Fragilaria conatruena var. binodie
H
H
Sp-I
(Ehr.) Grun.
Fragi1 aria conatruens var. capitata
R
H
Sp-I
Hérib.
Fragi iLaria conatruena var. minute
H
V
Sp-D
Temp. and M. Perag.
Fragilaria conati’u n var. pumila Grun.
R
V
Sp—I
Fragilaria conatruena var. eubsalina
V
V
SP
Rust.
FragiZaria conatruen8 var. venter
C
H
V
V V
0
R
V 0
S
L )
.
(Ehr.) Grun.
Fragilo.ria heideni Østr.
0
0
V
0 0
0
0
0 0
?
?
?
Fragilaria heideni var. iatvanffyi (Pant.)
0
0
V
0 0
0
0
0 0
?
?
?
Must.
Fragilaria inter,nedia Grun.
R
H
C
R H
H
R
R H
S,R
T
I — f l
Fragi7 aria intez,nedia var. continua A. Cl.
0
0
0
0 0
0
R
R 0
S
T
Sp—I
Fragilaria lapponica Grun.
H
H
0
0 0
0
H
P 0
S, H
T
Sp—I
Fragilaria lepto8tauron (Ehr.) Must.
C
H
H
C R
V
C
R R
S
R
Sp--D
Fragilaria leptoatauron var. dubia (Grun.)
V
v
V
V V
V
V
V V
S
H
I-fl
Hust.
Fragilaria leptoetauron var. foeeilie
H
V
V
H V
0
R
V 0
5
H
Sp-D
(Grun.) Rehákov
Fragilaria leptoatauron var. rhornboidea
0
V
0
0 0
0
0
0 0
S
R
D1
(Grun.) Must.
Fragilaria pantocaekii var. binodis (Pant.)
H
V
0
V 0
0
H
V 0
S
R
Sp 1
A. Cl.
Fragilaria pinnate Ehr.
C
A
V
C A
0
C
A A
S
P
Sp-D
Fragilaria pinnata var. intercedena (Grun.)
P.
V
0
H V
0
V
V 0
S
R
Sp 1
Must.
Fragilaria pinnate var. lancettula (Schum.)
R
C
A
V K
C
H R
S
R
Sp-I
Must.
T
T
T
(continued)
-------
TABLE 1 (continued)
PRIJSTLJLIA
o 0 0 0 0
o 0 0 0 0
o o 0 N 0
o o 0 N 0
V 0 0 R V
o Na PPa
o Na PPa
o Na PPa
o Ra PPa
o ; PPa
Name
0 V
C N
C N
V 0
00
V 0
0 0
V 0
00
0
N
V
0
V
0
0
0
0
Fragilaria 8piflo8a Sky.
Fragilario vaucheriae (KUtz.) Peters.
Fragilaria vaucheriae var. capitellata
(Grun.) Patr.
FragiZ .aria vau 62’; var. Zanceolata
A. Meyer
Fragi lana vaucheria. var. truncata
(Grey.) Grun.
Fragilani .a virescene Raif a
Fragilaria vireecena var. capitata østr.
Fragiidnia vireacena var. mesolepta
(R.abh.) Schönf.
Fragilania Vireacena var. oblongella Grun.
Fruatulia rhcanboidea (Ehr.) DeT.
Fruatulia rhcriboi4ea var. anphipieuroidea
(Grun.) DeT,
Fru tuija rhc*nboi4ea var. cra aainervia
(Bréb.) Ross
Fruatuija rh ,nboidea var. aaxonica
(Rabh.) DeT.
Fruetulia vulgaz’ia (Thw.) DeT.
Frustulia vulgani .s var. capitata Krasske
Frustulia weinhoidii Must.
aoMph ’ONgMA
Gomphonatna abbrevia turn Ag.
(k’mphonana abbreviati n var. inflata
Mu at.
Gomphonatna actuminatzan Ebr.
Gamphon nci acwninatz#n var. brebissonii
(Ktltz.) Grun.
Conr .,lwnerna acwninaturn var. coronata
(Ehr.) Rabh.
Lake
I II
Michigan
III
Lake
L11
0 0
C C
Huron
III
0
N
Lake Superior
I 11111
0 0 0
A C N
Primary
habitats
?
R,PP
Secondary
habitat
9
I
Depth
9
Sp—D
Notes
Distribution poorly known,
perhaps allochthonous
C R
V
A C N
R,PP
T
S—I
0 0
0
0 0 0
R
I
0 0
0
0 0 0
R
I
S—I
V 0
0
N V 0
S
N
Sp—I
0 0
0
V 0 0
S
N
Sp
0 0
0
0 0 0
S
R
I
0 0
0
N 0 0
S
N
Sp—I
V 0
0
0 0
0
V 0 0
N 0
0
N 0
0
N 0 0
—
0 0
0
0 0
0
N 0 0
PP
V 0
0
V 0
0
N 0 0
S
PP
N V
0
V 0
0
V 0 0
S
0 0
0
0 0
0
V 0 0
S
V 0
0
0 0
0
0 0 0
S
Historic samples only
S
S
S
0 V
C V
00
0 0
V 0
Sp— I
Sp— I
Sp— I
Sp— I
Sp— I
Sp— I
s—I
D
I—0
Sp— I
Sp— I
0
0
0
0
0
(continued)
-------
TABLE 1 (continued)
Name
Gomphonema acuminat-urn var. puaillLun
Grun.
Gomphonmna acuminaturn var. trigonocepha la
(Ehr.) Grun.
Gomphoneina affine Kiltz.
Gomphonena affine var. ineigne (Greg.)
Andrews
Goinphonema anguetatwn (KUtz.) Rabh.
Gamphonema anguatatunr var. productwn H V
Grun.
Gomphonema angustatuin var. Barcophagu8 0 0
(Greg.) Grun.
Gomphonema clevei Fricke V V
Gomphonen -,a gracile Ehr. H H
Gomphone,na g acile var. cymbelloides o o
Grun.
‘ Gcenphoneina gracile var. naviculacea (W. Sm.) H 0
Cl.
Gomphonana grovei N. Schmidt 0 H
Gomphonema helvetioum Brun 0 0
GomphoneiB erlenae (Grun.) Sky, and Meyer 0 0
Gonvphoneis herculeana (Ehr.) Cl. C R
Gomphonema intricatwn KUtz. A R
Gomphonema intricatum var. dichotornum R V
(I(Utz.) Grun.
Gomphonema intricatum var. foBeilis 0 0
Pant.
Gomphonema intricatwn var. pumila C R
Grun.
Gomphonema intricatv.m var. vibrio 0 0
(Ehr.) Cl.
Gomphonema lanceo la turn Ehr. H V
Gomphonerna lanceolaturn var. insignia V 0
(Greg.) Cl.
Gomphonana langicepa .Ehr. V 0
Previously reported as fossil,
perhaps allochthonous
(continued)
Lake Michigan
111111
o o V
Lake Huron
111111
0 0 0
Lake Superior
I 11111
R V )
Primary
habitats
Ha
Secondary
- habitats
PPa
Depth
ra
Sp—I
Notes
0
0 0
0 0
0
V 0 0
Ha
PPa
Sp
0
0 0
V 0
0
0 0 0
Ra
PPa
Hp—I
0
0 0
V 0
0
0 0 0
Ha
PPa
Sp—I
C
R H
C R
R
H R R
Ha
PPa
I—S
V
V 0
0
R V V
Ra
PPa
Sp—I
V
0 0
0
0 0 0
Ra
PPa
Sp—I
V
0 0
0
0 0 0
R
S
I
V
S R
V
H R R
Ha
PPa
Sp—I
V
0 0
0
0 0 0
Ha
—
I
0
R 0
0
C R 0
Ra
PPa
Hp—I
R
0 0
0
0 0 0
?
?
0
0 0
0
R 0 0
Ra
PPa
Sp—I
V
0 0
0
0 0 0
R
PPa
S—I
V
C H
V
C R V
H
PPa
S—I
V
A R
V
0 D R
Ha
PPa
D—Sp
0
R 0
0
R R V
Ha
—
D—Sp
0
0 0
0
C 0 0
Ra
—
Sp
V
C R
V
H H 0
Ha
S
D—Sp
0
H V
0
C R V
Ra
PPa
Sp—I
V
R V
V
V V 0
Ha
PPa
I—D
0
0 0
0
0 0 0
Ra
—
1—0
0
0 0
0
0 0 0
Ha
—
Historic samples
only
-------
TABLE 1 (continued)
Gyrosigma acumination (KUtz.) t abh.
Gyrosr9na attenuatum (KUtz.) Rabh.
H R V H H V 0 0 0
V V V V V V 0 0 0
Name
Lake Michigan
I II III
Lake Huron
I II III_
Lake Superior Primary Secondary Depth
III III habitats habitats
Notes
Gomphonenia lonqiaspe var. eubolavata
Grun.
Go nphona’na aubriwn Fricke
V
V
0
0
0
0
0
C
0
V
0
0
0
H
0
H
0
0
Ha
Ha
-
S
I
D—Sp
Historic samples only
Goniphonema OUvaasc idea Hust.
Gomphotwraa olivaaeojdga v ar. cochlearifoi nje
Mang.
Gomphonenu oljvaagzgn (Lyngb.) KHtz.
A
0
C
H
0
H
V
0
H
A
0
C
H
0
H
V
0
H
A
A
R
H
0
H
V
0
H
Ha
Ha
Ha
FPa
PPa
0-I
D—Sp
More abundant in historic
L. Michigan samples
Widely distributed
Gomphonema olivaoetvn var. calcarea
(Cl.) Cl.
Gomphonema parvuiwn (KUtz.) KUtz.
C
H
H
H
H
H
A
H
H
H
H
H
V
A
V
H
V
V
Ra
Ha
PPS
PPa
D-Sp
Sp—I
Ganphonema parvulzat var. exiliseima
Grun.
Gomphonenaz parvuiwn var. inioropua
(KUtz.) l.
Goinphorieina quadripunctatum (østr.) Wial.
0
V
0
0
V
0
0
V
0
0
0
0
0
0
0
0
0
0
C
0
H
H
0
V
0
0
0
Ha
Ha
Ha
—
S
-
Sp—I
I-D
1—0
Gcnnphonema aubclavatwn fo. gracilin (Rust.)
Woodhead and Tweed
Gomphonema euboiavatun, (Grun.) Grun.
0
V
0
0
0
0
0
0
0
0
0
0
V
H
0
V
0
0
Ra
Ha
S
Pl’a
Sp—I
0—I
Govnphonenia aphasrophorurn Ehr.
0
0
V
V
0
0
R
R
0
Ha
—
0—I
Gcrnphonen subtile Ehr.
V
V
0
H
V
0
H
H
0
Ha
—
Sp—I
Gcrphonana ubtjlg var. eagitta (Schum.) Cl.
V
0
0
0
0
0
H
H
0
Ha
S
Sp—I
Gomphonenu tergeetinwn (Grun.) Fricke
0
0
V
0
0
0
V
0
0
Ra
S
Sp—I
Gomphonema trunoatwn Ehr.
V
0
0
0
0
0
H
V
0
Ra
PPa
I-D
Gcrnphonema truncattan var. capitatum
(Ehr.) Patr.
Gcinphoneina turns Ehr.
0
0
0
0
V
0
0
0
0
0
0
0
R
V
H
0
0
0
Ha
Ra
PPa
—
Sp-I
Sp
Gornphonema ventricosum Greg.
0
0
0
0
0
0
C
0
0
Ha
PPa
I—D
Sv
T
I—U
GYROSIGMA
(continued)
-------
Rannaea arcaa (Ehr.) Patr.
liannaea arcus var. vnphioxy.s (Rabn.)
Patr.
Hannaea arcUs var. lvnearis dolmboe
HANTZSCIIIA
!Iantzschia wnphioxya (Ehr.) Grun.
Hantzechia amphioxys var. capitata
0. MUll.
TABLE 1 (continued)
Sp—I
Sp—I
I—D
Meloejra a.renaria Moore
Melosira undulata (Ehr.) KUtz.
0 0 0 0 0 0 V 0 0 SS
V d ö ô 0 0 V 0 0 S
D—Sp Oligotrophic
D More common in fossil material
from L. Superior
N SLe
Gyro8igma nodiferum (Grun.) Reim.
Gyrosigma scalproi4es (Rabh.) Cl.
Gyroeigma acioteriae (Sulliv. and Wormley)
Cl.
Gyro igma apenoeri.i (Quek.)
Griff and Henfr.
Gyroaigrra apsncer’ii var. curvula
(Grun.) Reim.
Gyroaigma temperei Cl.
Gyrosi.gma wornleyi (Sulliv.) Boyer
HANNA A
Lake
I
II
Michigan
III
Lake
I
Huron
II III
Lake
I
Superior
II III
Primary
habitats
Secondary
habitats
Depth
V
V
V
0
0 0
0
0
D
Sv
T
I—D
V
R
V
0
0 0
V
0
0
Sv
T
1—0
V
R
R
0
0 0
V
0
0
Sv
T
0—I
R
V
V
0
0 0
V
D
0
Sv
T
I—D
C R
V
V V V
V V
0
Sv
T
0 —I
Notes
0 Sv
T
I—D
o Sv
T
I
0
0
0
R 0
o o
o o
o V
V
0 0
D
0 0
o o
V
0 0
0
0 0
R 0
A R
0
Na
V 0
0 0
D
Ra
o 0
0 0
0
Ra
V V
V
V 0
V
V V
V
Sv
V V
V
0 0
0
V 0
0
Sv
0
0
0
MASTOGIQIA
T
T
MELOSIRA
Sp—I Very widely distributed
Sp—I
Maetogloia grevillei w. 3 n.
N
R
R
0
0
0
0
0
0
Sv
Sp—I
Mastogloia nithii Thu.
V
V
V
0
0
0
0
0
0
Sv
Sp—I
Mastogloia emithii var. cenphicephaia
Grun.
V
V
0
V
D
0
0
0
0
Sv —
Sp 1
Maatogloia amithii var. lacuetrt8
R
R
0
R
V
0
V
V
0
Sv -
Sp 1
Grun.
(continued)
-------
TABLE 1 (continued)
Neloaira unth4ata var. nor ,mii Arnott
?4eloairn variana Ag.
V 0 0 00 0 V 0 0 S
0 R C 0 R C 0 0 R S
Pr1 ary Secondary Depth
hg Ltat . habitat . ________-- Notes
- D
T S—I
N.ridion eiroulare (Grey.) Ag.
l4eridion circular. var. oonOt2’jc Jfl
(Ralfa) V.H.
N .4VICUL.4
Navicula aboensi . (Cl.) Rust.
Navioz4ia abeoluta Rust.
Navicula acoeptata Rust.
Naviouja acoomoda Must.
Naviouia anbigua Ehr.
Navioul.a wn.riaana Ehr.
Navicula cvnphibola var. parrieri
Perag. and Hérib.
Navicula anglica Raif a
Navicula anglioa var. aignata
Rust.
Navioula anglica var. aub .alaa
(Grun.) Cl.
Navioul.a anguatata W. Sin.
Navicula curora Soy.
Navicula baciliwn Ehr.
Navioula baloanioa Rust.
Naviai4a begeri Kraaake
Navicula bryophil .a Pet.ra.
Sp
Sp—I
Sp.
I—Sp
I—Sp
Sp—I
I
I—Sp Much more common in historic
L. lichi an samplea
N s.s
Lake Michigan
__i II III
l RIDIOPi
Lake Huron
I IX III
Lake Superior
_ I II III
V V
V
V 0
0
V V
V
R
V V
V
0 0
0
V
Sp—I
Sp—I
00
00
H H
V V
0 0
00
V 0
H H
H H
V V
V 0
H V
V V
R V
0 0
V V
0
0
V
V
V
0
0
V
R
0
0
0
0
0
0
0
00
00
V 0
00
0 0
00
00
H 0
00
00
00
H 0
V 0
00
0 0
00
0 V 0
0 HO
0 R V
0 00
0 V V
0 V 0
0 00
0 V V
0 V V
0 00
0 V 0
0 R V
0 H V
0 0 0
0 V 0
0 00
S
T
T
PB
0
0
0
0
0
0
0
0
0
0
3
0
0
0
0
0
Sv
Sv
Sv
Sv
3v
Sv
Sv
Sv
Sv
Sv
Sv
Sv
Sv
Sv
Sv
S
0-I
I— f l
Sp—I
Sp—I Much more common in historic
L. Michigan samples
Sp—I Much more common in historic
L. Michigan samples
Sp—I Much more common in historic
L. Michigan samples
Sp
I-fl
(continued)
-------
TABLE 1 (continued)
Name
Lake
Michigan
Lake
Huron
Lake
Superior
Primary
I
II
III
III
III
111111
habitats
Secondary
- habitats
Depth
V
V
H
V V 0
V V V
Notes
0
H
0
0
0
0
0
0
0
0
V
0
0
0
0
V
Sv
Sv
Sv
Sv
Sv
Sv
Sv
lv
Sv
Sv
Sv
Sv
PB
Sv
0 V 0
H 00
0 0 0
V 00
V 0 0
V 0 0
0 00
V 0 0
0 00
0 V 0
R 0 0
0 0 0
0 0 0
0 00
0 0 0
V V V
H V H
0 0 0
H V V
V V V
Navicula capitata Ehr.
Navicula capitata var. hungarica
(Grun.) Ross
Navicula capitata var. luneburgeneva
(Grun.) Patr.
Navicula capaa Hohn
V
V
V
V
V
0
V
0
0
-
i.-o
1-0
Sp-I
Navicula caroliniana Patr.
0
0
0
0
0
T
Sp—1
Navicula circumtexta Meist.
0
0
0
0
0
-
Sp—I
Navicuic citrus Krasske
0
0
0
0
0
-
Sp—1
Navicuja dementia Grun.
0
0
V
0
0
Sp
Navicula dementia var. linearia
Brander
Navicula dementia var. quadri8tvglflata
Mang.
Navicula cocconeifox,nja Greg.
0
0
V
0
0
0
V
V
C
0
0
R
0
0
V
-
Sp—I
Sp—I
5 P’
Navicula confervacea (KUtz.) Grun.
0
0
0
0
0
PP
Sp
Navicula contenta Grun.
0
0
V
0
0
Sp
Navicula contenta var. bicepa
(Am.) Grun.
Navicula coatul.ata Cl. and Grun.
0
R
V
V
0
0
0
0
0
0
D
Sp 1
Navicula cryptocephaloidea Rust.
V
0
0
0
0
Sv
I
Navicula cryptocephala KUtz.
R
V
R
V
V
Sv
Sp 1
Navicula cryptocephala var. inter,nedia
V.H.
Navicula cryptocephala var. lancettula
(Schwa.) Grun.
Navicula cryptocephala var. veneta
(KUtz.) Rabh.
NaVicula cU8pidata :KUtz.) KUtz.
V
V
V
V
V
0
V
V
R
0
H
V
0
0
V
V
0
0
V
V
0
•)
R
V
Sv
Sv
Sv
Sv
-
-
-
Sp-I
I
Sp-I
Sp-I
WaVicula cuapidata var. major Meist.
V
0
V
0
0
0
0
0
0
Sv
--
Sp-I
Navicula deouaaia Østr.
V
R
R
V
V
V
V
V
Sv
T
Sp-I
ijavicula elqinensia (Greg.) Ralfa
C)
0
V
0
0
0
V
0
0
Sv
Sp—I
Perhaps allochthonous
Ualophi lic
Poss ibly allochthonous
In deep living bryophyte
communities
Much more common in historic
L. Michigan samples
Widely distributed
Widely distributed
Widely distributed
(continued)
-------
TABLE 1 (continued)
Notes
0
0
0
0
0
0
0
V 0
00
V 0
0 0
R R
C R
R V
0
0
0
0
V
V
0
Sv
Sv
Sv
Sv
Sv
Sv
Sv
Na a
Lake
I II
0 0
0 0
0 0
Michigan
III
0
0
V
Lake
I
0
0
0
II
0
0
0
Huron
III
0
Lake Superior
III III
V 0 0
Priujary
habitats
Sv
-
Navicula •Zginenaia var. lata (14. Perag.)
Patr.
Navjauja el.gin.neiu v ar. roetrata
(A. Miyer) Patr.
NavicuZa exigua (Greg.) Grun.
Naviouja exigua var. capitata Patr.
V
V
0
0
0
Navicula exiguifoz nia Rust.
It
V
V
0
0
T
Navioula oxplanata Must.
ft
V
V
R
0
Navioula faa’ta Rust.
V
0
0
0
0
-
Navioulo fraota Must.
ft
0
0
0
0
Navicula gaotrifoiw ia Rust.
0
0
V
0
0
0
0
0
0
Sv
-
-
Naviouia gaetrion (Ehr.) IGitz.
Navioul.a gastrun var. oignata Hust.
V
ft
V
V
V
0
0
It
0
0
0
0
V
0
V
0
V
0
Sv
Sv
Naviouja gibbooa Must.
0
0
V
0
0
0
0
0
0
Sv
Navioula globo8a Meist.
0
0
0
0
0
0
V
0
0
Sv
Navicula gottlandica Grun.
0
0
ft
0
0
0
0
0
V
Sv
Navicul .a graciloides A. Mayer
V
It
It
0
V
It
0
V
0
Sv
Navioula gregaria Donk.
0
V
It
0
0
ft
0
0
0
Sv
Navicuia grinvnei Krasske
0
V
R
0
0
0
0
0
0
Sv
Naviouia gyaingensia Foged
0
0
0
0
0
0
V
0
0
Sv
Navioula hambergii Must.
V
0
0
0
0
0
0
0
0
Sv
T
Navwula haaaiaca Krasske
0
0
0
0
0
0
V
0
0
Sv
Navioula hasta Pant.
V
0
0
0
0
0
0
0
0
Sv
—
Navioula heufleri Grun.
0
V
0
0
0
0
0
V
0
Sv
Navicula heufleri var. leptocephala
(Br b.) Patr.
0
0
V
0
0
0
0
0
0
Sv
—
Secondary Depth
habitats !.hR&!
Sp—I
Sp—I
Sp— I
Sp—I
I—Sp
I—Sp
Sp—I
I—Sp
I
Sp— I
I
Sp—I
Sp
Sp—I
Sp—I
Sp—I
Sp—I
Sp
Sp—I
Sp
I-0
Sp
Sp— I
More common in historic Lake
Michigan samples
Probably allochthonous
Halophilic
Historic samples only
(continued)
-------
TABLE 1 (continued)
Lake Michigan Lake Huron Lake Superior Primary Secondary Depth
Name I II III I II III 111111 habitats habitats Notes
1 avicala huøtedtjj fo. obtuaa (Must.) Hust. 0 0 0 0 0 0 V 0 0 Sv -
Navicula imbricata Bock V 0 0 0 0 0 0 0 0 ? Perhaps aliochthonous
NaviauLa inaoaiabilia var. diaaipatoidea V 0 0 0 0 0 0 0 0 Sv — I
Must.
Naviouja integra (V. Sm.) Raifs 0 0 V 0 0 0 0 0 0 Sv Sp 1
Navicula intractata Must. 0 0 0 0 0 0 V 0 0 Sv Sp—I
Navicula jaernefeltii Must. N 0 0 R 0 0 C V 0 Sv Sp—D
NavicuLa krasskei Rust. 0 0 0 0 0 0 V 0 0 Sv Sp
Navicula lacuetrta Greg. N 0 0 V 0 0 V 0 0 Sv — I
Navicula lanceoZata (Ag.) KUtz. N R N N R N R R R Sv T Sp—I Widely distributed
Navicula lanceolata var. cymbula V 0 V 0 0 0 V V 0 Sv - Sp—I
(Dank.) Ci.
Naviculij l.atena Krasske V R V 0 0 0 0 0 0 Sv Sp—L
Navicula lepanderj Must. V 0 0 0 0 0 V 0 0 $v Sp—I Historic L. Michigan sample only
Navicula luaonertaia Must. V 0 0 0 0 0 0 0 0 Sv I
Navicula mediocrie Krasske 0 0 0 0 0 0 V 0 0 Sv — Sp
Navicula meni8cuiue ScILum. V 0 0 0 0 0 V 0 0 Sv T I
Navicula meniaculue var. obtuBa Must. R V V 0 0 0 0 0 0 Sv — I
Navicula meniaculua var. upaalienais N N R V V R V R R Sv T I
Grun.
Navicula micropupula Chain. V V 0 0 0 0 0 0 0 Sv - I—D
Navicula minima Grun. R V V V V V R V V Sv - 5 p—i Widely distributed
Navicula minima var. ol
-------
TABLE 1 (continued)
Lake Superior Priaary Secondary Depth
I II III habitats habitats
Notes
D—I
D
0
Sp
Sp—I
Sp—I
Possibly allochthonous
NaViolsjd mimi.o Zojd.a Rust.
Naviouja monoeuiata Rust.
Navioula muralifoi,rtia Rust.
Naujaula npAtI.oa guts.
Naviouja mutica va r. oo mii (Ruse) Crun.
NaViOU1O mutioa var.tropioa Rust.
Navj.cuj .a mutica var. undulata (Hilee) Grun.
Naviouja ?nutaoOl4ea Rust.
Navjoul.a wa fri .oop.ia V.11.
Navioula nsoventrjooea Rust.
Navioula nya.s.naia to. minor 0. MUll.
Navicul.a oblonga (K itz.) ICütz.
Naviouja odioea Wallace
Navioul .a oppugnata Rust.
Navjouj .a ordinarja ijust.
Navioula paanaenai .a A. Cl.
Navioula paca Hobo and Helleriu.
Navjcula paludosa Rust.
Navicula pelliculoea Ruse
Naj4oula peratomue Rust.
Navicula perpueilla (KUtz.) Grun.
Navjcula placenta Ehr.
Navjcuja placentula (Ehr.) K itz.
Sv
Sv
Sv
Sv
Sv
Sv
Sv
Lake Michigan Lake Huron
SI II III I II III ___________ _______
V 0 0 0 0 0 0 0 0 Sv —
V 0 0 0 0 0 0 0 0 Sv R
V 0 0 0 0 0 0 0 0 Sv R
0 0 0 0 0 0 V 0 0 Sv —
R V 0 R 0 0 K V 0 Sv K
V 0 V 0 0 0 0 0 0 Sv R
00 0 00 0 K 0 R
Va 0 00 0 00 —
V 0 0 00 0 K 0 -
00 0 V0 0 00 —
V 0 0 00 0 K 0
V V 0 V V 0 V V -
0 V K 00 0 00 —
K V V R 0 0 K V -
Va 0 00 0 00 —
0 0 0 0 0 0 V 0 0 Sv —
V 0 0 0 0 0 0 0 0 Sv T
C K V K R 0 R K 0 Sv R
0 V V 0 V 0 0 0 0 Sv —
K 0 V 0 0 0 0 0 0 Sv —
V 0 0 0 0 0 V 0 0 Sv —
0 0 V 0 0 0 0 0 0 Sv —
R V V V 0 0 0 0 0 Sv
0
0
0
0
0
0
0
0
0
Sp
Sp
Sp— I
Sp—I
Sp— I
Sp—I Widely distributed
I—Sp
Sp— I
Sv
Sv
I
Sp
0.-I
0-Sp
Sp— I
0—I
Sp— I
Sp— I
Sp—I More abundant in historic L.
Michigan samples
(cont inu d)
-------
TABLE 1 (continued)
Lake Michigan Lake Huron Lake Superior Primary Secondary Depth
Name -________________ 111111 I I I III 111111 habitats habitats Notes
Navi ula placentula var. ro8tr 2ta V R V 0 0 0 V 0 0 Sv Sp—I
A. Mayer
Navicula platycephal a 0. Mull. V 0 0 0 0 0 0 0 0 Sv — I—D
Navicula platy8toraa var. pantoc8ekii V R R V V 0 0 0 0 Sv I—D
Wils. and Kolbe
Navicula potzgeri Reim. 0 V 0 0 0 0 0 0 0 Sv - I—D
NavicuLa protracta (Grun.) Cl. V V V 0 0 0 0 0 0 Sv - Sp—D
Navicula protracta var. elliptica V R R 0 0 V 0 0 0 Sv - 1D
Gall ilc
Navicula protracta fo. euboapitata K V V 0 0 0 0 V 0 Sv — 1—0
(Wila. and Pot.) Rust.
Navicula pseudcclemantia Must. V 0 0 0 0 0 K 0 0 Sv Sp—I
iVaVjcula paeudoaoutjfor nje Rust. R V V K 0 0 K K V Sv K Sp 1
Navicula pseudoventra1 is Rust. 0 0 V 0 0 0 V 0 0 Sv Sp—I
.4 Navicula pupuZ.a lCütz. R R V K V 0 K R V Sv Sp—1 Widely distributed
Navicula pupula var. aquaeductae 0 0 V 0 0 0 0 0 0 Sv I
(Kraaske) Huat.
Nap icuZ.a pupuia var. capitata Rust. K K V K K V R V V Sv Sp—I
Navicula pupula var. elliptica Rust. K V 0 R V 0 0 0 0 Sv 1D
Navicula pupula var. mutata (Krasske) Rust. R V V 0 0 0 0 0 0 Sv Sp—I More common in historic L.
Michigan collections
Navicula pupuZ.a var. rectangularia R V V R V C) K R 0 Sv Sp 1
(Greg.) Cl.
Navicula pupula var. roetrata Rust. R V V V V 0 V 0 0 Sv Sp—I More common in historic L.
Michigan samples.
Navicula pygmaea Kütz. 0 V R 0 0 V 0 0 0 3v Sp—I Halophilic
Navicula quadripartita Rust. 0 0 V 0 0 0 0 0 0 Sv Sp
Navicula radioaa Kütz. C C R C C R C C K Sv T 1—0
Navjcula radioea var. parva Wallace K C) C) R C) 0 R 0 0 Sv I—D
Napjcula rc.djosa var. tenella (Br b.) C R R C K K C K K Sv T Sp—D
Cl. and Mull.
Navjouia recondita ior a V 0 0 0 0 0 0 0 C) R D
(continued)
-------
TABLE 1 (continued)
V V R V V R V V V Sv
V V K V V V V V V Sv
K 0 0 R 0 0 K V 0 Sv
K V V K V V V V 0 Sv
V 0 0 0 0 0 0 0 0 Sv
K 0 0 0 0 0 0 0 0 K
o o V 0 0 0 0 0 0 Sv
K C R V K V R K K Pv
o o 0 V 0 0 V 0 0 Sv
V 0 0 V 0 0 K V 0 Sv
R V 0 R V 0 K V V Sv
V K K V K V 0 0 0 Sv
V 0 0 V 0 0 V 0 0 Sv
o V 0 0 0 0 V K 0 Sv
o o V 0 0 0 0 0 0 Sv
V 0 0 V 0 0 K V 0 Sv
K V V K V 0 K K 0 Sv
K V 0 K V 0 K K R Sv
R V V 0 0 0 0 0 0 Sv
o v o 0 0 0 0 0 0 Sv
K V V R 0 0 V V 0 Sv
V 0 0 0 0 0 0 0 0 Sv
K V 0 0 0 0 0 0 0 Sv
Lake
Michigan
Lake Huron
Name I
II
III
I II III
Lake Superior
I II III
Pr1 ary Secondary Depth
habitats habitats
Notes
tiavicula rginhardtjj Grun.
NaviauZ.a reinhardtii var. eUiptica H rib.
Navicula rhynahooephal.a Kütz.
Navicula rotunda Must.
Navicula aaljnarwi Grun.
Navicula ac pria8amannii Must.
Navicula achoenfeidji Must.
Navioula eouteiloi4ea W. Sm.
Navicula aoutifoxinia Grun.
Navjouja awnenoidea Huet.
Navic,4a aemira4ioidea Must.
Navioula seminuiwn Grun.
Navioula aeminulum var. intermedia
Must.
Navicula a2milio Kras8ke
Navicuta simplex Kraieke
Navicula ekab1 taoheW8kyi Sabelina
Navicula 8trOemii Hust.
Navicula atroesei ( str.) A. Cl.
Navicula eplendicula Van Land.
Navicula eubcoatulata Oust.
Navicula eubhc,iiulata Grun.
Navicula 8ul nuralt8 Must.
iVavicula aubocculta Oust.
Sp—I
Sp—I
Sp—I Only historic L. Michigan
samples
Sp—I
I Probably allochthonous
D
Sp—I
Sp—D
Sp—I
D- I
D- I
I—Sp
D— I
S I
Sp—I
Sp—D
Sp—D
Sp— I
I —0
I
Sp—I
1—0 Historic L. Michigan samples only
0-I
(continued)
-------
TABLE 1 (continued)
Lake Michigan Lake Huron ake Superior Primary Secondary Depth
Name I II III 111111 111111 habitats habitats pge ______ Notes
Navicula suhrhynclwcephala Rust. 0 V 0 0 0 0 0 0 0 Sv - I
Navicula 8ubrotundata Rust. V 0 0 V 0 0 R 0 0 Sv Sp—I
Navicula subaulcata Host. 0 0 V 0 0 0 0 0 0 Sv I
Navicula aubtiliesima Cl. 0 0 0 0 0 0 V 0 0 PB Sp usually in sp.
Navicula tantula Rust. V R R 0 V R 0 V R Sv Sp—I
Navicufa tecta Krasske 0 0 0 0 0 0 V 0 0 Sv Sp—I
Navicula terminata Hu8t. 0 0 V 0 0 0 0 0 0 Sv Sp—t Probably allochthonous
Navicula tridentula Krasske 0 0 0 0 0 0 V 0 0 Sv Sp
Navicula tridentula var. pc.rallela 0 0 0 0 0 0 V 0 0 Sv Sp
Krasske
Navicula tripunctata (0.F. M il1.) Bory C R R C R R R R R Sv D—Sp
Navicula tripunctata var. cuneata 0 R R 0 0 0 0 0 0 Sv 1D
(Lauby) Stoerm. and Yang
Navicula tripunctata var. echizonemoidea V R V V B V 0 0 0 By I-D
(V.H.) Patr.
Navicula tuacula Ehr. R V V V V V V V V Sv — Sp—I More common in historic L.
Michigan samples.
Nauicui.a tuacula fo. minor Rust. V B B 0 V V 0 0 0 Sv I-D
Navicula tuacula fo. obtusa Must. R V V R V 0 V 0 0 Sv — 1—0
Navicula tuacula var. roatrata V V 0 0 0 0 0 0 0 Sv 1D
Must.
Navicula vanheurckii Patr. 0 V V 0 0 0 0 0 0 Sv — D—I May be misidentified RV of
Achrianthes bioreti
Navicula variostriata Krasske 0 0 0 0 0 0 V 0 0 Sv Sp
Navicul.a Ventosa Hust. 0 0 V 0 0 0 0 0 0 Sv — Sp—I
Navicula ventralis Krasske 0 0 V 0 0 0 0 V 0 Sv ISp
Navicula ventraZ-is to. 6Vnplez Rust. 0 0 0 0 0 0 0 V 0 Sv — Sp
Navicula viridul.a (Kiitz.) Ehr. V R V V R V 0 V V Sv SpI
Navicula viridula var. avenacea (Br b.) V R B 0 0 V 0 0 0 Sv - I
V. H.
(continued)
-------
TABT.2 1 (continued)
Lake Michigan Lake Huron Lake Superior Primary Secondary Depth
Name 111111 I I I III £11111 habitats habitats Notes
Navicula Viridula var. linearia Huat. v R v 0 V 0 V V o Sv l-Sp
Navicu a virduLa var. roeteiLata 0 V V 0 o o o V o Sv - I-Sp
(KUtz.) Cl.
Nauioul.a uitabunda Must. 0 0 0 0 0 0 V 0 0 Sv ISp
Navicuia vulpina Kiitz. V V 0 V 0 0 N V V Sv I—Sp
Navjc,uia wittrockii (Lagerat.) Temp. and R V 0 N V o a v Sv I—Sp
N. Perag.
?Jai,inula sanoni Huqt. V N a o o o o o o Sv I—Sp
NEIDILIN
Neidiurn affine (Ehr.) Pfitz. N 0 0 N 0 0 R V 0 Sv I—D More common in historic
L. Michigan samples
Neidiwn affine var. amphirhynchue (Ehr.) 0 0 0 0 0 0 N 0 0 Sv Sp
Cl.
Neidiwn affina var. hwnerua Reim. N 0 0 K 0 0 N 0 0 Sv Sp—I Historic L. Michigan sample only
Neidiwn affine var. undulatum (Grim.) Cl. 0 0 0 0 0 0 V 0 0 Sv - Sp
Neidiwn binode (Ehr.) Rust. V V 0 0 0 0 0 0 0 Sv - I
Neidiwn biai4oatwn (Lagerat.) Cl. 0 0 0 0 0 0 V 0 0 Sv Sp
Neidiwn bieuloatwn, vat. baioa enee V 0 0 0 0 0 V 0 0 Sv — Sp—I Historic L. Michigan sample only
(Sky, and Meyer) Reim.
Neidiwn aaltnen østr. V 0 0 0 0 0 V 0 0 Sv Sp—I
Neidiwn diatincte-punctatwn Host. 0 0 0 V 0 0 V 0 0 Sv 0—I
Neidiwn dubiwn (Ehr.) Cl. V V V 0 V V V V 0 Sv - Sp-D
Nejdjun d.ubjtgn o.conatrictwn Rust. V V 0 V 0 0 V V 0 Sv Sp 0
Neidiwn hitchcockii (Ehr.) Cl. V 0 0 V 0 0 V V 0 Sv Sp 1
Nejdiun, india (Ehr.) Cl. V V 0 V 0 0 V V 0 Sv Sp1
Neidiwn india var. wnphigcnnphua (Ehr.) V V 0 0 V 0 V V 0 Sv Sp 1
A. Mayer
Neidium india var. vernalj Reich. V 0 0 V 0 0 V V 0 Sv Sp—l
Neidium koaolwi Heresch. V 0 0 0 0 0 0 0 0 Sv I—I)
(continued)
-------
TABLE 1 (continued)
£Veidium sacoenae Reim.
Neidjum temperei Reim.
NITZSCHI.4
Lake Superior
I II III
V V 0 Sv
0 0 0 S
V 0 0 S
Sp—I
0—I
Sp—I
Lake
Michigan
Lake
Huron
Maine I
II
III
I
II
II I
Neidium koziowi var. bawalenBis fo. robusta V 0
Stoerm.
Neidium ladogense (Cl.) Stoerm. and Yang
Primary Secondary Depth
habitats habitats raqge
0 0 0 0 0 0 0 Sv - D
Notes
o o
V 0
o o
V R
C C
o o
R R
R R
o o
R V
o o
o v
C R
o v
C N
V R
V N
V 0
R N
o j
o v
Nitaaahia aouZ.a Hantz.
Nitzaohia cmnphibia Grun.
Nitz8chia cjnphibia var. fos8ilis Grun.
Nitzmchia angu8tata (W. Sm.) Grun.
Nitzachia anguotata var. acuta Grun.
Nttmachuz apiculata (Greg.) Grun.
Nitzechja bulnheimiana (Rabh.) ILL. Sm.
Nitz chia capiteil.ata Rust.
Nitaschia COflPflUfli8 Rabh.
Nitzachja denticula Grun.
IVitz8chuz fjljforenja (W. Sm.) Schutt
Nitzachja fonticola Grun.
Nitaschja frustulum (KUtz.) Grun.
Nitz8chia fruBtulum var. pez,flinuta
Crun.
Nitzachja frustuiwn var. subsalvna
Rust.
Nitsachia hungarica Grun.
Nitsachia ignorata Krasske
Nit schja in ecta Hust.
V
0
0
V
R
0
V
0
V
V
R
0
V
V
R
R
K
0
V
0
0
V 0
o 0
o 0
V V
K R
o o
R R
C R
o o
V 0
o o
o o
A K
o 0
C R
o R
o 0
o o
V V
o 0
o o
0
0
0
V
K
0
V
0
0
0
0
0
0
0
R
R
0
0
V
0
0
T
K
S
K
R
o V V iv
o v V Sv
R K 0 Sv
o v V Sv
A C V Sv
o o 0 Sv
o 0 0 Sv
o 0 0 Sv
o 0 0 Sv
A R 0 Sv
O 0 0 PP
t
K V V Sv
K K K Sv
K R R Sv
V 0 0 iv
O V 0 Sv
O V 0 Sv
o o 0 Sv
I -D
1—0
Sp—I
I—Sp
I —D
1:
I —D
S p—I
Sp—I
1—0
S—I
S p—I
Sp—D
Sp-D
I
1—0
Sp
I
(continued)
-------
TABLE 1 (continued)
Lake Michigan Lake Huron Lake Superior Primary Secondary Depth
Ij I I Ij IIi liii habitats habItats ran e
Njtaaehja inter’nedja Hantz. 0 0 0 0 0 0 R 0 0 Rv - 1-0
Nitzeohia interrupta (Reich.) Huat. V 0 0 0 0 0 0 0 0 Sv — I
Nita8chia Zinec.ria (A8.) W. Sm. V 0 R 0 V R 0 0 0 Sv T Sp—D
Nitzacjhja linearia var. tenuje (Kutz.) 0 0 V 0 0 0 0 0 0 Sv T Sp—I
Grun.
Nitzeahja Zuaonenaj8 Huat. R V 0 R 0 0 C R 0 SSv — Sp-I
Vitzeahia palea h itz.) W. Sm. R R R R R K R I( Sv Sp—D Very vid2ly distributed
IVita8chia parvula W. Sm. 0 0 V 0 0 0 0 0 0 Sv Sp—I
Nitaachia r nana Grun. V V V 0 V V V V V Sv — 1—0
Nitzaahja ci u,a (KUtz.) W. Sm. V C) 0 0 0 0 0 0 0 Sv - 1—0
!htzgchja eigiiiojdea (Nitz.) W. Sm. V V V V V V V V V Sv T Sp—I
1’) Alitzechia ainuata var. to.beljaj’ja V 0 0 V e 0 V 0 0 S•, Sp—i
(Grun.) Grun.
Nitaaahia aubljneari8 Huot. V V R 0 0 R 0 V V Sv Sp—I
Nitae hja ther’maija (Ehr.) Auersw. 0 0 V 0 0 0 C 0 0 Sv 1—0
Nitzachia tropica Oust. V 0 0 0 1) 0 1) 0 0 Sv ID
Nitzachia tryblionella Hantz. 0 0 V 0 0 0 0 0 0 Sv — 1—0
iVi.tzachia tryblionelta var. debilia ‘) 0 V 0 0 0 0 0 0 Sv — 1—0
(Am.) A. Mayer
Nitz8chia tryblionelZa var. levidenai8 V V K 0 0 R 0 0 0 Sv 1—0
(W. Sm.) Grun.
Nitzaahja ver niculari8 (Ktitz.) Rabh. 0 0 V 0 0 0 0 0 0 Sv S—I
OESTRUPIA
Qeatrupia aachariaai (Reich.) Stoerm. V V V 0 0 0 0 0 0 Sv — I—D
and Yang
Oe trupia aacharia8i var. undulata V V V 0 0 0 0 0 0 Sv 1-0
(Schulz) Stoerm. and Yang
(continued)
-------
TABLE 1 (continued)
Lake Michigan Lake Huron Lake Superior Primary Secondary Depth
N ame ___________ - I II III I 11 111 I II III habitata habitats Rotes
OPgPh’oRA
Opephora aneata Uohn and Hellerm. C R V R R 0 R R 0 Ra Sa 1-0
Opephora martyi Hérib. R V V H V V C R V Ra Sa 1—0
PINNULARIA
Pinnularia abau.jensi (Pant.) Koss 0 0 0 0 0 0 V 0 0 Sv Sp
Pinnularia abaujensis var. lineari s 0 0 0 0 0 0 V 0 0 Sv Sp
(Rust.) Patr.
Pinnularia aixzujensie var. subundulata 0 0 0 0 0 0 V 0 0 Sv Sp
(A. Mayer) Patr.
Pinnularia acrosphaer a W. Sm. V 0 0 0 0 0 0 0 0 Sv I
Pinnularia biceps Greg. 0 0 V 0 0 0 V 0 0 Sv - Sp—i
Pinnularia biceps to. petersenii 0 0 V 0 0 0 0 0 0 Sv I Perhaps allochthonous
Ross
Pinnularia borealis Ehr. R 0 0 0 0 0 C V 0 Sv — Sp—D Only deep localities in L.
i -ji Michigan
Pinnularia brandelii Cl. 0 0 0 0 0 0 V 0 0 Sv - Sp
Pinnularia braunii var. ctjnphicephala 0 0 0 0 0 0 V 0 0 Sv Sp
(A. Mayer) Rust.
Pinnularia brebis8onii (KUtz.) Rabh. V V V V 0 0 0 V 0 Sv — Sp—I
Pinnularia brebieeonii var. diminuta 0 0 0 0 0 0 V 0 0 Sv Sp
(Grun.) Cl.
Pinnularia brevicoatata Cl. 0 0 0 0 0 () V 0 0 Sv Sp
Pinnularia burkij Patr. 0 0 V 0 0 0 0 0 0 Sv Probably allochthonous
Pinnularia divergens var. bczcjllaris 0 0 0 0 0 0 V 0 0 Sv Sp
(M. Perag.) Mills
Pinnularia divergene var. elliptica 0 0 0 0 0 0 V 0 0 Sv Sp
(Grun.) Cl.
Pinnularia gentilie (Donk.) Cl. 0 0 0 0 0 0 V 0 0 Sv Sp
Pinnularia globicepa var. krockjj (Grun.) V 0 0 0 0 0 0 0 0 Sv Sp—I
Cl.
Pinnularia inter,nedia (Lagerst.) Cl. 0 0 0 0 0 0 V 0 0 Sv Sp
Pinnula.ria interrupta var. crassior V 0 V 0 0 0 0 0 0 Sv - Sp-I
(Grun.) Cl.
Pinnularja latevittata var. domingensis 0 0 0 0 0 0 V 0 0 Sv Sp
Cl.
(continued)
-------
TABLE 1 (continued)
Lake Michigan Lake Huron Lake Superior Primary Secondary Depth
I ‘L L ’ LL Jij it cs J akt t1
Pinnuia ’ia legw ien (Ehr.) Ehr. 0 0 V 0 () 0 0 0 0 Sv - Probably allochthonous
Pjnnj4a,.ja laptosoma (Grun.) Cl. 0 0 V 0 0 0 0 0 0 Sv Probably allochthonous
Pinnul.arja l.ptoeaea to. eri genaie 0 0 0 0 0 0 V 0 0 Sv Sp
A. Mayer
PznnuZ wja io,jor (KLitz.) Rabh. 0 0 V 0 0 0 0 0 0 Sv Sp—t Probably allochthonoua
PLnnula rja mseolepta (Ehr.) W. Sm. 0 0 0 0 0 0 V 0 0 Sv — Sp
Pinnularja mt.oroatauron (Ehr.) Cl. V 0 0 V 0 0 V 0 0 Sv I-Sp
Pinnulaj’ia mioroet4uron var. biunduZ.ata 0 0 0 0 0 0 V 0 0 Sv Sp
0. M l i ii.
Pinnujarja malaria (Grun.) Cl. 0 0 0 0 0 0 V 0 0 Sv Sp
Pinnularja nodoaa (Ehr.) W. Sm. 0 0 0 0 0 0 V 0 0 Sv Sp
Pinnularia obsoura Kraieke 0 0 0 0 0 0 V 0 0 Sv Sp
Pinnujarja ruttnerj Rust. 0 0 V 0 0 0 C 0 0 Sv - 0
Pjnnujarja a ’nioruojata A. Cl. 0 0 0 0 0 0 V 0 0 Sv Sp
Pinnujaz’ja aubroatrat.a A. Cl. 0 0 0 0 0 0 V 0 0 Sv Sp
Pinnularia aubatce at.ophora Huet. 0 0 0 0 0 0 R 0 0 Sv Sp
Pinnularia tenuia Greg. 0 0 0 0 0 0 R 0 0 Sv Sp
Pinnularia tcnuia var. interrupta (Pont.) 0 0 0 0 0 0 V 0 0 Sv Sp
A. Cl.
Pinnularia ternitina (Ehr.) Patr. V 0 0 0 0 0 R 0 0 Sv Sp—l
Pinnularia tibstana Rust. V 0 0 0 0 0 0 0 0 Sv — Sp-I Historic L. Michigan Sample only
Pinnularia undulata Greg. V 0 0 0 0 0 0 0 0 Sv Sp-I
Pinnularia undulata var. BUbUndUlatcj 0 0 0 0 0 0 R 0 0 Sv Sp
Crun.
Pjnnularja vjrjdja (Nitz.)Ehr. R 0 0 R 0 0 0 V 0 Sv I-Sp
Pinnularia viridia var. o rtutata (Grun.) 0 0 0 0 0 0 V 0 0 Sv Sp
Cl.
(continued)
-------
TABLE 1 (contInued)
Lake Michigan Lake Huron Lake Superior Primary Secondary Dej,th
Name III 1111 111111 habitats habitats ran e Notes
PL4GIOTROPIS
Plagiotropia lepidcptera var. proboscidea V V P. V V P. 0 0 0 SSv T I
(Cl.) Reite.
PLEUROSIG?4A
Pleuro8igma de7 icatulum W. Sm. V 0 0 0 0 0 0 0 0 Sv V
RROICOSPHENIA
Rhoicoephenia aurvata (KUtz.) Crun. C C A C C A V P. C PPE Ra S—I
Rhoicoaphenia ourvata var. aubaouta 0 3 V (J fl 0 0 0 1 P.a ?Pa S-I
M. Schmidt
RROPALODI.4
iji Rhopaiodia gibba (Ehr .) 0. Mull. C R R C P. R R R V PPa S 1t)
Ln
Rhopalodia gibba var. ventricosa (KUtz.) R V 0 0 0 0 0 0 0 PPa S D 1
H. Perag. and H. Perag.
Rhopalodia gibberula (Ehr.) 0. MUll. 0 V V 0 0 0 0 V 0 PPa S S—I
Rhopalodia parallela (Crun.) 0. MUll. 0 0 0 0 0 0 V 0 0 PPa S Sp—I
sTAuRoNErs
Stauroneis acutiuacula M. Perag. and H rib. V P. V V R V V V V Sv I- f l
Stauror&eie agreatia Peters. 0 0 0 0 0 0 V 0 0 Sv Sp Aerophytic, possibly allochthonc*2s
Stcw.roneie ancepe Ehr. V V V 0 0 0 0 0 0 Sv Sp—I
Stauroneis anceps var. canericana Reiie. 0 0 0 0 0 0 V V 0 Sv — Sp—I
Stauroneia ancepa vat. hyalina Srun and 0 V 0 0 0 0 0 0 0 Sv I Possibly allochthonous
M. Perag.
Stauroneia anceps vat. siberica Grun. V V 0 0 0 0 0 0 0 Sv - I
9taurorieia anceps to. gracihs Rabh. 0 0 0 3 0 0 V 0 0 Sv Sp
Stauroneis dilatata Ehr. V 0 0 V 0 0 P. V 0 Sv Sp-I Historic L. Michigan samples only
(continued)
-------
TABLE 1 (continued)
Lake Michigan Lake Huron Lake Superior Primary Secondary Depth
Name - I II II I I 1111 I - II III habItats habitats ran&e Notes
Stauroneja diZatata var. ajcaLen8j8 Sky. V 0 0 0 C) 0 LC V 0 Sv
and Meyer
Stauroneja krieyeri Patr. 0 0 0 0 3 0 U V 0 Sv Sp—I
Stauroneja krieyeri fo. undulata Must. o 0 0 0 V 0 0 Sv Sp
Stauroneja living8tonij Reim. 0 0 0 0 0 0 V 0 0 Sv — Sp
Stauroneja nobjijo var. ‘aconiana (Stodd.) V 0 0 0 o o o o o Sv I-C)
Re im.
Stauponejs phoenicenteron (Nitz.) Ehr. v o v o 0 ‘/ v o Sv I —I)
Staurongj phoenicenteron var. breuj 8 v o o o 0 0 0 0 0 Sv I0 Historic samples only
Dippel
Stauroneje phoenicenteron fo. gracili 0 0 0 0 0 0 V 0 0 Sv - Sp—I
(Ehr.) Must.
Stauroneje phoenicenteron var.janceolata V 0 0 0 0 0 V V 0 Sv Sp—I
(Kutz.) Brun
çj Stauroneie emithii Grun. V 0 V V 0 0 V V 0 Sv - Sp-I
Stw ronej amithii var. minima Haworth o 0 0 0 0 0 V 0 0 Sv — Sp Host other reports fossil
STENOPTFJROBIA
Stenopterobja interrncdia (Lewis) V.H. o o 0 0 0 0 V 0 0 Sv - Sp
SURIRELL.4
Surirella angu8ta Kdtz. V R U V U 0 V V V Sv T 1—0 Abundant in winter plankton in
polluted Waters
Supirella anguBta var. pandurifomnje W. Sm. V 0 0 0 0 0 0 0 0 Sv - 1—0 Only historic L. Michigan samples
Surirelia bieeriata Bréb. and Godey 0 0 0 0 0 0 V V 0 Sv T Sp—D
Surjrella bjaerjata var. bifrona (Ehr.) V 0 0 V 0 0 V V 0 Sv T Sp—D More abundant in historic L.
Hust. Michigan samples
SurjrelZa delicatjcsjma Lewis 0 0 0 V 0 0 V 1) 0 Sv - Sp—I
Surirella elegano Ehr. V 0 0 0 0 0 0 0 0 Sv — 1-0 iatoric L. Michigan samples only
Surirella quaten7alencjs Ehr. 0 0 V 0 0 0 0 0 0 Sv — 1D
Surireija linearic W. Sm. V 0 0 V 0 0 V V 0 Sv T 1—0 More abundant in historic L.
Michigan samples
Surjrella linearis var. constrjcta (Ehr.) V 0 0 V 0 0 V V 0 Sv T l—D
Grun.
(continued)
-------
TABLE 1 (continued)
Name
Surirella ljnearja var. helvetica (Bru )
Heist.
Surirella ovaiis Bréb.
Surirella ovatcz Kiitz.
Surirell.a ovata var. pinnata (W. Sm.) Rabh.
Surirella ovata var. sauna (W. Sm.) Rabh.
Surirella robu8ta Var. plendida (Ehr.)
V. H.
Surirella tenera var. nervosa A.S.
Surirella tenui .savna Must.
SYNEDRA
Spnedra aCU8 itUts.
U,
Synedra capitata Ehr.
Synedra fasciculata (Ag.) KUtz.
Synedra goulardi Bréb.
Synedra parasitica (W. Sm.) Rust.
Synedra parasitica var. suboonstricta
(Crun.) Rust.
Synedra puichella Ralfs
Synedra runlpefl8 Klitz.
Synedra rumpens var. foiniliaris (KUtz.)
Must.
Synedra rumpena var. fragilarioidea
Crun.
Synedra ruinpens var. meneghiniana
Crun.
Synedra tenera W. Sm.
Synedra ulna (Ritz.) Ehr.
Synedra ulna ear. acqualic (Kfltz.) Must.
Notea
Lake Michigan
III III
Lake Huron
111111
Lake
I
Superior
II III
Primary
habitats
Secondary
habitats
Depth
V 0
0
0 0 0
V
V
0
Sv
T
1—0
o V
R
0 V C
0
0
0
Sv
T
1—0
V V
R
V V C
0
0
0
Sv
T
1—U
V V
C
V V C
0
0
0
Sv
T
1-0
o o
0
0 0 R
0
0
0
Sv
T
I—U
V 0
0
0 0 0
0
0
0
Sv
T
I—U
o o
V
0 0 0
0
0
0
Sv
T
1—0
o 0
V
0 0 0
0 0
0
Se
-
I
Halophilic
Common in plankton of polluted
streams
Common in plankton of polluted
streams
Saginaw Bay only
Halophil Ic
Probably allochthonous
Halophil ic
Very widely distributed
C
R
R
R
H
V
C
H
H
Ra
S
S—I
V
0
V
R
0
0
V
0
0
Ha
PPa
S—I
0
0
R
0
0
V
0
0
0
Ha
PPa
I
0
0
V
0
0
0
0
0
0
Ra
PPa
S—I
V
V
V
0
V
V
V
V
0
Ra
PPa
S—I
V
V
V
0
0
0
V
V
0
Ha
PPa
S—I
0
0
R
0
0
H
0
0
0
Ra
PPa
S—I
H
R
V
R
V
V
C
H
V
Ha
P}’a
S—I
0
0
0
0
0
0
V
0
0
Ra
PPa
Sp
5.
V
V
5.
V
0
C
R
5.
Ra
PFa
S—I
V
0
0
0
0
0
1)
0
0
Ra
PPa
I
C
5.
0
C
5.
0
C
P
0
Ma
T
S—I
C
C
C
C
C
C
I)
C
C
Re
PPa
S—I
0
V
V
0
0
0
0
0
0
Re
PPa
S—I
(continued)
-------
0
0
0
V
0
0
0
TABLE 1 (continued)
o R V
o o 0
R V V
o V 0
o c V
o 0 0
o C V
o o a
0 0 0
o c R
o a a
Primary Secondary Depth
! !
Ra PPa S—I
Ra PPa S—I
Re PPa S—I
Ra PPa S—I
Ra PPa S1
Ra PPa S—I
Re PPa S—I
Re PPa S—I
its PPa S—I
its PPa S—I
Ra PPa S—I
Lake
Michigan
Lake
Huron
Lake
Superior
Name I
II
III
I
II
III
I
II
III
Synedra ulna var. arnphirhynchue (Rhr.)
Grun.
Synedra ulna var. bicepe (Klitz.) 1(irchn.
it
.
0
V
V
0
V
R
0
V
0
Synedra ulna var. clavicepa Must.
it
C
it
it
it
Synedra ama var. constrwta Venkt.
V
V
V
V
a
Synedra ama var. oxyrhynchue (KUtz.) V.H.
R
V
it
V
Synedra ama var. ozyrhynchua f.
med iocontracta (Forti) Must.
Synedra ama var. apathulifera (Crun.) V.11.
R
it
0
V
0
C
0
V
Syngdr’a ama var. aubaequalia (Grun.) V.11.
0
0
0
0
Synedra vaucheriae (KUta.) Kutz.
C
C
0
it
U i
03
Synedra vaacheriae var. capiteliata
(Grun.) Cl.
Synedra vaucheriae var. truncata (Grey.)
C
V
R
0
C
0
it
0
Notes
More abundant in historic L.
Michigan samples
0
0
V
0
0
0
0
0
0
it
0
Grun.
TABSLLARIA
Ta.bell rzr ia flocculoaa (Roth) Kütz.
A C R A C K D C R Ra S
S—I
-------
APPENDIX I
Plates. Benthic diatom taxa are pictured and the corresponding collection
locality is noted. All specimens are presented at 1000X and a 10 pm bar is
given on photomicrograph number 2 of each plate. Voucher specimens are housed
at the Great Lakes Research Division, University of Michigan.
PLATE I
1. Melosira undulata , valve view (VV), Lake Superior.
2. H. undulata var. normannii , VV, Lake Michigan.
3. H. varians , Lake Michigan.
4. Fragilaria constricta fo. stricta , Lake Superior.
5. F. leptostauron var. fossilis , Lake Michigan.
6. Opephora martyi , Lake Michigan.
7. Synedra capitata , Lake Huron.
8. S. ulna var. spathulif era , Lake Michigan.
9. S. puichella , Lake Michigan.
10. Diatoma vulgare var. linearis , Lake Michigan.
11. D. anceps , Lake Superior.
12. Eunotia incisa , Lake Michigan.
13. Tabellaria flocculosa , Lake Superior.
14. Achnanthes clevei var. rostrata , pseudoraphe valve (PRy), Lake Michigan.
15. A. lanceolata var. haynaldii , raphe valve CRy), Lake Michigan.
16. Eunotia praerupta , Lake Michigan.
17. E. formica , Lake Michigan.
18. Achnanthes lanceolata var. abbrevlata , PRy, Lake Michigan.
19. A. hauckiana var. rostrata , PRy, Lake Michigan.
20. A. hauckiana var. rostrata , RV, Lake Michigan.
21. Rhoicosphenia curvata , Lake Huron.
22. Coccorieis disculus , PRy, Lake Michigan.
23. C. placentula var. rouxii , RV, Lake Superior.
24. C. pediculus , post—auxospore, RV, Lake Huron.
59
-------
. :;7i
Tj
% 1:..;
I .
V
60
-------
PLATE II
1. Mastoglola smithii var. amphicephala , Lake Michigan.
2. Anomoeoneis follis , Lake Superior.
3. Frustulia rhomboides var. amphipleuroides , Lake Michigan.
4. Gyrosigma spencerii var. curvula , Lake Michigan.
5. Stauroneis dilatata var. baicalensis , Lake Michigan.
6. Capcrtogramma crucicula , Lake Michigan.
7. Stauroneis phoenicenteron var. lanceolata , Lake Michigan.
8. Oestrupia zachariasi var. undulata , Lake Michigan.
9. Neidium sp., Lake Superior.
10. Diploneis finnica , Lake Superior.
11. Diploneis elliptica var. pygmaea , Lake Michigan.
12. Caloneis ventricosa var. minuta , Lake Michigan.
13. C. nubicola , Lake Superior.
14. Neidium hitchcockii , Lake Superior.
15. N. sacoense , Lake Michigan.
16. Caloneis lewisii , Lake Superior.
17. C. alpestris , Lake Michigan.
18. C. amphisbaena , Lake Michigan.
19. Pinnularia nodosa , Lake Superior.
20. P. brandelii , Lake Superior.
21. P. borealis , Lake Michigan.
61
-------
-------
PLATE III
1. Navicula pygmaea , Lake Michigan.
2. N. sp., Lake Michigan.
3. N. amphibola var. perrieri , Lake Michigan.
4. N. lacustris , Lake Michigan.
5. N. pseudoscutiformis , Lake Superior.
6. N. cocconeiformis , Lake Michigan.
7. N. scutelloides , Lake Michigan.
8. N. terminata , Lake Michigan.
9. N. mutica var. undulata , Lake Superior.
10. N. jaernefeltii , Lake Superior.
11. N. subhamulata , Lake Michigan.
12. N. integra , Lake Michigan.
13. N. farta , Lake Michigan.
14. N. lanceolata var. cymbula , Lake Michigan.
15. N. bacillum , Lake Michigan.
16. N. cuspidata , Lake Michigan.
17. N. americana , Lake Superior.
18. N. levanderi , Lake Michigan.
19. N. reinhardtii , Lake Michigan.
20. N. reinhardtii var. elliptica , Lake Michigan.
21. N. wittrockii , Lake Michigan.
22. N. wittrockii , Lake Michigan.
23. N. oblonga , Lake Michigan.
24. N. tuscula , Lake Michigan.
25. N. aurora , Lake Michigan.
63
-------
0
-------
PLATE IV
1. Gomphonema acuminatum var. coronata , Lake Michigan.
2. C. sphaerophorum , Lake Huron.
3. C. truncatum , Lake Michigan.
4. C. truncatum var. capitatum , Lake Michigan.
5. C. grovel , Lake Michigan.
6. C. abbreviatum var. inflata , Lake Michigan.
7. Gomphoneis eriense , Lake Michigan.
8. C. herculeana , Lake Huron.
9. Didymosphenia geminata , Lake Superior.
10. Cymbella cistula var. gibbosa , Lake Huron.
11. Amphora calumetica , Lake Michigan.
12. A. hemicycla , Lake Michigan.
13. A. michiganensis , Lake Michigan.
14. A. huronensis , Lake Huron.
15. Cymbella sinuata var. antiqua , Lake Huron.
16. C. triangulatum , Lake Michigan.
65
-------
/
66
A
I
I
.1
-------
PLATE V
1. Nitzschia acula , Lake Michigan.
2. N. palea , Lake Michigan.
3. N. denticula , Lake Huron.
4. N. tryblionella var. levidensis , Lake Michigan.
5. N. tryblionella , Lake Michigan.
6. Bacillaria paxillifer , Lake Michigan.
7. Nitzschia angustata var. acuta , Lake Huron.
8. N. parvula , Lake Michigan.
9. N. denticula , Lake Michigan.
10. N. sinuata var. tabellaria , Lake Michigan.
11. N. aniphibia , Lake Michigan.
12. N. sp., Lake Michigan.
13. N. luzonensis , Lake Michigan.
14. Surlrella angusta , Lake Michigan.
15. Rhopalodia gibba var. ventricosa , Lake Michigan.
16. Nitzschia romana , Lake Michigan.
17. Denticula tenuis var. crassula , Lake Michigan.
18. Hantzschia atuphioxys , Lake Michigan.
19. Surirella ovata , Lake Michigan.
20. S. angusta , Lake Michigan.
21. Stenopterobia intermedia , Lake Superior.
22. Rhopalodia gibberula , Lake Michigan.
23. R. gibba , Lake Michigan.
67
-------
68
-------
PLATE VI
1. Cymatopleura solea var. apiculata , Lake Michigan.
2. Surirella robusta var. splendida , Lake Michigan.
3. S. guatemalensis , Lake Michigan.
4. Plagiotropis lepidoptera var. proboscidea , Lake Michigan.
69
-------
I
I
- . - j ‘.c- . ,.
I - , .
*
* - _
r
p
3
70
-------
PLATE VII
1. Surirella biseriate var. bifrons , Lake Huron.
2. Entomoneis ornata , Lake Michigan.
3. Epithemia turgida , Lake Michigan.
4. E. smithii , Lake Michigan.
5. Campylodiscus noricus var. hibernica , Lake Huron.
6. Epithemia adnata , Lake Michigan.
7. E. adnata var. saxonica , Lake Michigan.
8. E. adnata var. porcellus , Lake Michigan.
9. E. argus var. alpestris , Lake Michigan.
71
-------
4
I - ’ ? , ‘ .
.
I
a.
0
I
S
72
-------
TECHNICAL REPORT DATA
(Please read Ins.izructions on the reverse before completing)
1. REPORT NO. 2.
EPA—6 00/3—80--073
3. RECIPIENTS ACCESSIOP#NO.
4. TITLE AND SUBTITLE
Characteristics of Benthic Algal Communities in
the Upper Great Lakes
5. REPORT DATE
July 1980 issuing date
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Eugene F. Stoermer
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Great Lakes Research Division
University of Michigan
Ann Arbor, Michigan 48109
10. PROGRAM ELEMENT NO.
11.CONTRACT/GRANTNO.
803037
12. SPONSORING AGENCY NAME AND ADDRESS
Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Duluth, Minnesota 55804
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
EPA/600/03
15. SUPPLEMENTARY NOTES
Large Lakes Research Station, 9311 Groh Road, Grosse lie, Michigan 48138
16. ABSTRACT
The upper Great Lakes contain a diverse array of benthic algal communities.
Characteristic communities occupy substrates from the supralittoral to depths in
excess of 30 m. Diatoms are the dominant taxonomic group present in terms of
numbers, and usually in terms of biomass, except in eutrophic areas. Communities
in areas receiving minimal direct anthropogenic impact are extremely diverse in
terms of both species richness and population evenness. The populations which
comprise these communities are generally reported from extremely oligotrophic
habitats. A significant number of populations found in undisturbed habitats in
the upper Great Lakes have not been previously reported from North America.
Benthic communities in more eutrophic areas are characterized by a greater
abundance of eurytopic and widely distributed taxa. Many of these species are
familiar elements of the floras of smaller, mesotrophic to eutrophic lakes.
The communities of directly impacted areas contain a more limited suite of
very tolerant populations, usually occurring in high abundance.
17. KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
C. COSATI Field/Group
Algae, Water Quality
Benthic Algae, Lake
Michigan, Huron, and
Superior
06F
18. DISTRIBUTION STATEMENT
Released to Public
19. SECURITY CLASS (This Report)
Unlimited
21. NO. OF PAGES
79
20. SECURITY CLASS (This page)
Unlimited
22. PRICE
EPA Form 2220•1 (9-73)
73
U.S. GOVEROMLOT PRINTING OFFICE: 1980-—657—1N5/0073
------- |