WATER POLLUTION CONTROL RESEARCH SERIES • 13050 ELDO2/72
      FRESHWATER
ECOSYSTEMS

Identification
Manual
THE
GENUS ARGULUS
(CRUSTACEA: BRANCHIURA)
OF THE
UNITED STATES
U,5, ENVIRONMENTAL PROTECTION AGENCY

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                 Biota of Freshwater Ecosystems


                   Identification Manual  No. 2
THE  GENUS ARGULUS (CRUSTACEA:BRANCHIURA)  OF THE  UNITED STATES
                                 by

                        Roger F. Cressey
                     Smithsonian Institution
                      Washington D.C.  20560
                              for the

                 ENVIRONMENTAL PROTECTION AGENCY
                        Project # 18050  ELD

                        Contract # 14-12-894
                           February  1972
           For sale by the Superintendent of Documents, U.S. Government Printing Office
                      Washington, D.C. 20402 - Price $2.50
                          Stock Number 5501-0366

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            endorsement or recommendation for use.
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                                11

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                        '  FOREWORD
"The genus Argulus (Crustacea:Branchiura) of the United
States" is the second of a series of identification manuals
for selected taxa of invertebrates occurring in freshwater
systems.  These documents prepared by the Oceanography and
Limnology Program, Smithsonian Institution, for the Environ-
mental Protection Agency will contribute toward improving
the quality of the data upon which environmental decisions
are based.

Additional amnuals will include, but not necessarily be limit-
ed to, freshwater representatives of the following groups:
amphipod crustaceans (Gammaridae), isopod crustaceans (Aselli-
dae), decapod crayfish crustaceans (Astacidae), leeches
(Hirudinea), polychaete worms (Polychaeta), freshwater plan-
arians (Turbellaria), aquatic dryopoid beetles (DryopoideaJ
and freshwater clams (Sphaeriacea).
                              111

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                   ABSTRACT
Twenty three species of Argulus are recognised
as valid from the 37 reported from the United
States.  An illustrated key is provided to
these species.   Distribution and host records
are also included.

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                               CONTENTS






Section                                                            PaŁe



  I    Introduction                                                  1




          Collecting, Preservation and Identification                2




  II   Species List with Distribution and Hosts                      3




  III  Key to the United States species of Apgulus                   5




  IV   References                                                   11




  V    Index of Scientific Names                                    13
                                  vn

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                                 FIGURES
                                                                    Page
1  Respiratory areas of eatostonrij nobiliSj  st-izostethi,,              5
   alosae} biaolor, and megalops

2  Mouth tubes of borealiSj megalpoSj  fuseus and japonicus            5

3  Illustrations of characters used  in the identification             6
   of Argulus

4  Antennal area of borealiSj latieauddj  lepidostei,                   7
   maeulosus and alosae

5  Sclerotized sucker rods of meehccni.3 melanost-Lchuss                  8
   pugettens-is} japon-ious, maculosus,  versicolor,
   appendioulosus, diversus and nobilis

6  Basal plates of second maxillae of  flavesoens,                      9
   lepidostei,  meehani-, ohesapedkens'Ls3  tattoauda3
   funduli, catostomi, fusous and floridens-is
                                 Vlll

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                               SECTION I

                             INTRODUCTION

Thirty seven species of Argulus have been described or reported from
the United States since the description of A. aatostomi by Dana and
Herrick in 1837.  Of the 6 genera of Branchiura which have been
described from various parts of the world, the genus Argulus is the
only one so far recorded from the United States.  In the preparation
of this key the present author examined 279 collections including
type specimens of 31 species contained in the collections of the Smith-
sonian Institution.  In addition to this material 56 collections
solicited from various freshwater and marine biologists in the U. S.
were examined.  These collections and the donors will be acknowledged
in a forthcoming monograph of the genus.  The type specimen of
A. funduli- was sent to me by Dr. T. Wolff of the Copenhagen Museum.

From the examination of this material I was able to reduce the number
of valid species to 23.  A number of species had been placed in synonomy
by Meehan in 1940 but Wilson resurrected 8 of these in 1944.  It is my
opinion that Meehan's earlier opinions regarding these synonomys were
correct.

Both Meehan  (1940) and Wilson (1944) published a key to the genus.
They contain, however, a number of species not found in the United
States.

The key presented herein is applicable to either sex.  The key has been
constructed for use by non-specialists.  Other characters than those
chosen could be used as well but these might require a more intimate
knowledge of this group of parasites.

Several species included in this key have been reported only from the
coastal environment.  I feel confident that collections made in the
freshwater drainages of these coastal areas would produce the same
species and hence I have included them.  Argulus ftaoesoens3 for ex-
ample, has been collected from the Mississippi River as far north as
Iowa and is common to the coastal waters of the Gulf of Mexico as well.

Discussions of life history and effects of the parasite on the host are
beyond the scope of this paper.  These aspects will be considered else-
where .

Illustrations with labeled, taxonomically important structures are
provided in lieu of a glossary.

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              COLLECTING, PRESERVATION AND IDENTIFICATION

Because individuals of Argulus are "loosely" associated with their
hosts collection depends on rapid examination of captured fish.
Individuals may be found anywhere on the body surface of the host and
in the mouth and gill chamber.  Furthermore, they are commonly found
in freshwater and coastal plankton samples.

Material can be initially preserved in 70 percent ethyl alcohol or
10 percent formalin.   Material preserved in  formalin should be
transferred to alcohol within a few weeks and material should remain
in 70 percent alcohol for long term storage.

For microscopic examination specimens can be temporarily mounted in
lactic acid.  This clears the specimen sufficient for examination of
appendages.  Material should be examined in  alcohol prior to clearing
as the respiratory areas often show up better under reflected rather
than transmitted light.  If the respiratory  areas are obscured by the
legs it may be necessary to remove one side  of the carapace and mount
it ventral side up in lactic acid.  Dilute chlorozol black can be used
as a last resort to stain the borders of the respiratory areas if
other methods fail.  Once cleared no further dissection is necessary
in order to see the characters (Fig.  3)  cited in this key-

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                              SECTION  II

              SPECIES LIST WITH DISTRIBUTION AND HOSTS
Argulus alosae Gould, 1841.  Distribution:   east  coast of U.  S.  from
     Maine to Texas. Hosts:  Alosa3 Clupea3  Dorosoma3 Tautogolabrus
     Lepisosteus3 Opsanus3 Cynoso-ion,
Argulus appendioulosus Wilson,  1907.  Distribution:  Vermont, Michigan,
     Kentucky, Iowa, Wisconsin, Texas, Wyoming, South Dakota.  Hosts:
     Stizostedlon3 Iotalurus3 Mioropterus, Ictiobus3 Catostomus,
     Dorosoma.
Argulus bioolor Bere, 1936.  Distribution:   southeast coast  of  U. S.
     from North Carolina to  Louisiana.   Hosts:  Strongylura, Morone3
     Gob-ionellus 3 M-ioropogon, Scomboromorus3 Dorosoma, Khinoptera.
Argulus borealis Wilson, 1912.  Distribution:  northwest coast of U.  S.
     Hosts:  Lepidopsetta, Cymatogaster.
Argulus oatostomi Dana and Herrick, 1837.  Distribution:  northeast
     U. S. from Minnesota to Vermont  and south as far as Maryland.
     Host:  Catostomus3  cyprinids.
Argulus  ohesapeakensis Cressey,  1971.   Distribution:  central east
     coast of U. S.  from Maryland to  North Carolina.  Hosts:  Opsanus,
     Anguilla3 Raehycentron3 Paralichthys.
Argulus diversus Wilson, 1944.  Distribution:  Indiana.  Host:
     Ameri-urus.
Argulus flaoesoens Wilson, 1916.   Distribution:   southeastern U.S. -
     Mississippi River System and Coastal Gulf of Mexico.   Hosts:
     Amia3 Mioropterus3 Mi.cropogon3 Paraliohthys3  Mugil3 Dasyatis.
Argulus floridensis  Meehan,  1940.  Distribution:   gulf coast  of  U. S.
     Host:  Mugi-l.
Argulus funduli Kroyer, 1863.   Distribution:  east coast of U. S. from
     Maine to Mississippi.   Hosts:  Fundulus, Lagodon, Chaetodon.
Argulus fuscus Bere, 1936.   Distribution:  gulf coast of U. S.   Hosts:
     OrthopristiSj Traehinotus.
Argulus  japonious Thiele, 1900.   Distribution:   entire U.  S. Host:
     goldfish  {Corassi-us) .
Argulus latioauda Smith, 1873.  Distribution:  northeast coast of U.  S.
     Hosts:  Opsanus3 Prionotus3  Pseudopleuron^otes3 Anguilla, Conger:
     "Sculpin".
Argulus lepi-doste-i Kellicott, 1877.   Distribution: Mississippi  River
     System and Gulf coast of Florida.   Host:  Lepisosteus.
Argulus maaulosus Wilson, 1902.   Distribution:  Michigan,  Indiana,
     Missouri, Iowa, Louisiana, New York.  Hosts: Amia3 Esox, Umbra.
Argulus mee'hani Cressey, 1971.  Distribution:  Florida.  Host:
     Lepisosteus.
Argulus megalops Smith, 1873.   Distribution:  east coast of U. S. from
     Mass, to Florida.  Hosts:  Chilomyoterus3 Ogeoaephalus3  Synodus3
     Prionotus3 Tautoga, Aleutera, Lophius,  Paraliohthys, M-iorogadus,
     Raia.

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Argulus melanostichus Wilson, 1935.  Distribution:  California.
     Host:  unknown.
Argulus mississ-ipp-iensis Wilson 1916.  Distribution:   Iowa.
     Host: Lepisosteus.
Argulus nobilis Thiele, 1904.  Distribution:  Mississippi, Texas.
     Host:  Lepisosteus.
Argulus pugettensis Dana, 1853.  Distribution:  northern west  coast
     of U. S.  Hosts:  Salmo, Ernbiotooa, Amphistichus.
Argulus stizostethi Kellicott, 1880.  Distribution:  northeast U.  S
     from Minnesota to Maine.  Hosts:  Ace-ipenser3 Alosa, Esox3
     NotroptSj Salvelinus3 GasterosteuSj Coregonus.
Argulus versicolor Wilson, 1902.  Distribution:  eastern U. S. from
     Mass, to Texas.  Hosts:   Esox, Amblophites, "perch".

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                              SECTION III

              KEY TO THE UNITED STATES SPECIES OF ARGULUS
       Smaller respiratory area entirely anterior to larger area
          (Figs ID , E , and F)	  2
          Smaller respiratory area in part or entirely lateral to
          larger area (Figs 1A, B, and C)	v.	 14
                     B
C
        Fig. 1.  Respiratory areas: A - catostomi", B - nobil-is;
        C - st-Lzostethi; D - alosae; E - bicolov; F - megalops
2 (1)  Mouth tube with spinels or scales on basal half....
       Mouth tube without spines or scales on basal half.
                                       3
                                       9
                                                            D
        Fig. 2.  Mouth tubes: A
        D - japonicus.
  -  borealis;  B -  megalops;  C - fuscus;

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                                           FIRST ANTENNA (Ai)
                                           SECOND ANTENNA (A2>
                                            SUCKER

                                            MOUTH TUBE

                                            SECOND  MAXILLA (MX2)

                                            ACCESSORY SPINE OF MX2

                                            BASAL PLATE


                                            RESPIRATORY  AREAS
                                            THORACIC LEG
                                           NATATORY LOBE
                                            ABDOMEN
    A
                                           A! TERMINAL SPINE


                                           Aj ANTERIOR   "
                                           A, MEDIAL     ii
                                           A, POSTERIOR
    B
                                           -POSTANTENNAL SPINE
Fig. 3.  A - Argulus appendiculosus,  female with ventral struc-
tures labeled; B   Argulus borealis,  female antennal area
labeled.

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3 (2)  Accessory spine present near base of second maxilla  (Fig. 3A)..4
       Accessory spine absent from near base of second
          maxilla,...,..,..,...	 funduli Kroyer


4 (3)  More than 12 elements in sclerotized sucker rods	.5
       Less than 12 elements in sclerotized sucker rods	6


5 (4)  Outermost spine of basal plate represented by
          sclerotized ridge  (Fig. 6H)	fusous Bere
       All three spines of basal plate well-
          developed	flopidens-is  Meehan


6 (4)  Scales present on mouth tube  (Fig. 2B); posterior respiratory
          area with scalloped edge (Fig. IF)	megalops Smith
       Spines present on mouth tube  (Figs  2A,  C )	7



7 (6)  Antennal spines fingerlike (Figs  4A, C); 4-5 spines
          on base of mouth tube  (Fig. 2A)	 borealis Wilson
       Antennal spines stout (Figs   4B, E) ', cluster of
          several spines on mouth tube  (Fig. 2C)	8
                                           Fig. 4.  Antennal  area.
                                           A- borealis;  B-  lat-ioauda;
                                           C- lep-idoste-i; D-  maoulosus;
                                           E- alosae.

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 8 (7)  Posterior respiratory area bent toward mid-line in
           posterior half (Fig. IE)	 bioolor Bere
        Posterior respiratory area not bent toward mid-
           line in posterior half  (Fig- ID)	 alosae Gould


 9 (2)  More than 10 elements in sclerotized sucker rods	 10
        Less than 10 elements in sclerotized sucker rods	 11
10 (9)  More than 17 elements in sucker rods
           (Fig.  5B)	melanostiohus Wilson
        Less than 17 elements in sucker rods
           (Fig.  sc)	pugettens-is Dana


11 (9)  More than 5 elements in sucker rods (Fig. 5D).. japonieus Thiele
        Less than 5 elements in sucker rods	12
                A
B
C
I
      Fig. 5.  Sclerotized sucker rods.  A- meehani; B - melanost-iahus;
      C - pugettensia;  D - joponieus;  E - n.aoulosus; F - versi-oolor;
      G - appendioulosus;  H - diversus; I - nobilis.

12 (11) Antennal spines spatulate (Fig. 4B); spines on
           basal plate with cusps (Fig. 6E)	  latioauda Smith
        Antennal spines not spatulate	 13


13 (12) First antennal posterior spine  fingerlike; spines on
           basal plate longer than wide (Fig. 6A)	 flavesaens Wilson
        First antennal posterior spine  blunt; spines on basal
           plate usually  as wide as  long (Fig. 6V)ehesapeakens-i8 Cressey
14 (1 )  Postantennal spine double (Fig.  4D)	 15
        Postantennal spine single	 17

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15 (14)  Two or three elements in sucker rods (Fig. 5E~)maaulosus Wilson
         More than three elements in sucker rods	16


16 (15)  Basal element in sucker rod bell-shaped (Fig. 5H)
         	„	diversus Wilson
         Basal element in sucker rod not expanded at
            base (Fig. 5F),.,	versi-oolov Wilson


17 (14)  Anteriormost respiratory area with posterior part
            extending along outer edge of posterior respiratory area
            (Fig. 1C); mouth tube with patch of spines at base
            	stizostethi Kellicott
         Smaller respiratory area entirely within inner lateral
            margin of larger area (Figs 1A, B);  no spines or scales
            at base of mouth tube 	18


18 (17)  Outermost spine of basal plate at least twice as wide as
            either of the other two (Fig. 6G)..oatostomi Dana § Herrick
         All three spiries of basal plate of about equal width	19
       i   A
                         B
                                                                    E
                                     G
       Fig. 6.  Basal plates of second maxillae.  A - flavescens;
    B - 1ep'ldo&'be^i'f C- meefomi; D - ckeaapeakensis; E - laiid'auda;
    F - fUnduli; G - catostomi; H- fusous.

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19 (18)  Posterior first antennal spine present. .m-ississi-pp-iensis Wilson
         Posterior first antennal spine absent	20
20 (19)  Sucker rods of two elements, distal element considerably
            longer than proximal  (Fig. 5G)	appendi-culosus Wilson
         Sucker rods of more than two elements	21
21 (20)  Basal plate with scales and few setae on surface'
            (Fig. 6 )	lepidostei  Kellicott
         Basal plate with few setae only (Fig. 6C)	22
22 (21)  Sucker rods composed of more than 10 elements  (Fig.  51)....
         	 nob'll'is  Thiele
         Sucker rods composed of less than 10 elements  (Fig.  5A)....
         	meehan-L Cressey
                                  10

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                               SECTION IV

                               REFERENCES

Bere, Ruby. 1936. Parasitic copepods from Gulf of Mexico fish.
     American Midland Naturalist, 17 (3): 577-625.
Cressey; Roger  F. 1971. Two new argulids (Crustacea:Branchiura)
     from the Eastern United States. Proceedings of the Biological
     Society of Washington, 84 (31): 253-258.
Meehan, 0. Lloyd. 1940. A review of the parasitic Crustacea of the
     genus Argulus in the collections of the United States National
     Museum. Proceedings of the United States National Museum,
     88 (3087): 459-522.
Wilson, Charles B. 1944. Parasitic copepods in the United States
     National Museum. Proceedings of the United States National
     Museum, 94 (3177): 529-582.
                                 11

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                                SECTION V

                        INDEX OF SCIENTIFIC NAMES
Aoa-ipenser , 4
Aleutera, 3
Alosa, 3,4
alosae (Argulus),   3,5,7,8
Amblophites , 4
Amer-iurus , 3
Amia, 3
Amphistiahus , 4
Angu-illa, 3
appendioulosus  (Argulus),  3,6,8,10
Argulus,  1,2
- alosae, 3,5,7,8
- appendiaulosus ,  3,6,8,10
            , 3,5,8
     oatostom-i,  1,5,9
     ohesapeakensis , 3,8,9
     d-iversus , 3,8,9
     flavesaens ,  1 , 8 , 9
     flor-idensis ,  3,7,9
     funduli ,  1,7,9
     fusous ,  3,5,7,9
     japon-ious ,  3,5,8
     lat'ioauda ,  3,7,8,9
     lepidostei,  3,7,9,10
     maoulosus ,  3,7,8,9
     meehani ,  3,8,9,10
     megalopSj 3,5,7
     melanostiohus , 4,8
     m-iss-iss'ipp'iens'is , 4,10
     nobi-lis ,  4,5,8,10
     pugettens'Ls ,  4,8
     vevsicolor, 4,8,9
         (ATgulus) >  3,5,8
l>oTea1is  (ATulus) .  3,5,6,7
Carassius , 3
eatostomi , (ATgulus) ,  1 > 5 , 9
Catostomus , 3
Chaetodon, 3
chesapeakens-ls  (Argulus) , 3,8,9
Ch-ilomycterus ,  3
Clupea, 3
Conger , 3
Coregonus , 4
Cymatogastev, 3
Cynosci-on, 3
eyprinids, 3
Dasyatis, 3
diversus  (Argulus), 3,8,9
DoTosoma, 3
Embiotoca, 4
ffeoar, 3,4
flaveseens (Avgulus),  1,8,9
floT-Ldens-is (Argulus),  3,7,9
funduli. (Argulus) , 1,7,9
Fundulus, 3
fusous  (Argulus),  3,5,7,9
Gasterosteus, 4
Gobionellus, 3
goldfish, 3
lotalurus, 3
Ictio'bus, 3
japoniaus (Argulus), 3,5,8
Lagodon, 3
lat'ioauda (Argulus) , 3,7,8,9
Lep-idopsetta, 3
lep-idoste-i (Argulus),  3,7,9,10
Lepidosteus, 3,4
Lophius, 3
maaulosus (Argulus), 3,7,8,9
meehani, (Argulus), 3,8,9,10
megalops  (Argulus), 3,5,7
melanost-iohus  (Argulus), 4,8
Miorogadus, 3
M-ieropogon, 3
M-iaropterus, 3
m-ississippiensis  (Argulus), 4,10
Morone, 3
Mugil,  3
nob-ilis (Argulus), 4,5,8,10
Notropis, 4
Ogoooephalus, 3
Opsanus, 3
Orthopristis, 3
Paralichthys, 3
perch,  4
Pr-ionotus, 3
Pseudopleuronectes, 3
pugettensis (Argulus),  4,8
Rachycentron, 3
                                    13

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Raia, 3
Rhinoptera, 3
Salmo, 4
Salvelinus, 4
Saomboromo'Pus, 3
sculpin, 3
Stizostedion, 3
stizostethi (Argulus), 4,5,9
Strongylura, 3
Synodus, 3
Tautoga, 3
Tautoglabrus, 3
Traehinotus, 3
Umbra, 3
           (Argulus), 4,8,9
                                   14

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   SELECTED WATER
   RESOURCES ABSTRACTS

   INPUT TRANSACTION FORM
                       1. Report No.
                                            3.  Accession No.
                                            w
  4. Title Biota  of Freshwater Ecosystems  Identification
  Manual No.  2    THE GENUS Argulus  (CRUSTACEA:BRANCHIURA)  OF
  THE  UNITED  STATES,
   7. Author(s)
              Cressey, R.  F.
   9. Organization
               Smithsonian  Institution
              Washington,  D.  C.


  12. Sponsoring Organization

  15. Supplementary Notes
                                            5.  Report Date

                                            6.

                                            5.  Performing Organization
                                               Report No.

                                            10.  Project No.

                                                 18050 ELD
                                             .  Contract/Grant No.
                                                 14-12-894

                                            13.  Type of Report and
                                               Period Covered
  16. Abstract
   Twenty three species  of Argulus are recognised as valid from  the 37 reported
   from the United States. An illustrated  key is provided to these species.
   Distribution and host records  are also  included.
  17a. Descriptors
               *Aquatic fauna,  *United States, *Fish  parasite,  Distribution.
  17b. Identifiers
               identification manual, *Illustrated  key, *Freshwater Branchiura,
    *Crustacea,
  17c. COWRR Field & Group
  18. Availability
19. Security Class.
   (Report)

20. Security Class.
   (Page)
  Abstractor   ROger  p.  Cressey
21. No. of
   Pages

22. Price
                                                           Send To:
                                                           WATER RESOURCES SCIENTIFIC INFORMATION CENTER
                                                           U.S DEPARTMENT OF THE INTERIOR
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