Systematic and Ecological Discussion 



Suborder Natantia 



Body almost always laterally compressed. Ros- 

 trum usually compressed and serrated. First 

 abdominal segment not much smaller than rest. 

 Antennules generally with stylocerite; antenna] 

 scale generally large and lamellar. Legs usually 

 slender, except sometimes a stout chelate limb or 

 pair, which may be any one of first three pairs; 

 with basipodite and ischiopodite very rarely 

 coalesced and with only one fixed point in carpo- 

 propodal articulation (with some doubtful excep- 

 tions) ; sometimes withexopodites; podobranchiae 

 hardly ever present on first three and never on 

 last two pairs ; male genital apertures in articular 

 membrane. Pleopods always present in full num- 

 ber, well developed, used for swimming (Caiman, 

 1909). 



Section Penaeidea 



Pleura of second abdominal segment not over- 

 lapping those of first segment. Antennules gen- 

 erally with stylocerite. Mandibular palps straight. 

 First maxillipeds without expansion at base of 

 exopodite, endopodite long; second maxillipeds 

 with terminal articles normal; third maxillipeds 

 with seven articles. Third legs chelate (except 

 when much reduced), not stouter than first pair. 

 First pleopods of male bearing sexual apparatus 

 (Caiman, 1909). 



Family Penaeidae 



Body somewhat or considerably compressed. 

 Rostrum usually well developed, laterally com- 

 pressed, often with teeth. Eyes moderate or 

 greatly elongate. Antennules with two flagella; 

 basal article of peduncle hollowed out dorsally 

 for eye, with stylocerite on basal outer margin. 

 Mandible with incisor process and palp of one 

 or two articles. First three pairs of legs similar, 

 chelate, slender, increasing in length posteriorly; 

 fourth and fifth legs well developed, simple 

 (Schmitt, 1921). 



Remarks. — For most species treated in this 

 handbook information on natural history is in- 

 cluded in the separate species accounts. In the 



case of parasites found in certain penaeids, such 

 citation has proved too cumbersome. Parasites in 

 this group have been studied only recently. Host 

 specificity and life cycles of the parasites are im- 

 perfectly known and identification of some forms 

 is uncertain. The interested student is referred to 

 a review of most of the known parasites given 

 by Hutton, Sogandares-Bernal, Eldred, Ingle, and 

 Woodburn (1959), and Iversen and Manning 

 (1959). 



Spelling of the name Penaeus and related gen- 

 eric names has unfortunately not been uniform. 

 Gunter (1957) reviewed these circumstances and 

 re-emphasized that under the International Code, 

 original spelling must be observed. He included a 

 list of the genera of Penaeidae. 



KEY TO SUBFAMILIES IN THE CAROLINAS 



a. Postorbital spine present Solenocerinae (p. 14). 



aa. Postorbital spine absent. 



b. Carapace without a median dentate crest, except 



occasionally over eyes Penaeinae (p. 17). 



bb. Carapace with a median dentate crest extending 

 nearly or entirely to posterior margin 



Sicyoninae (p. 32). 



Subfamily Solenocerinae 



Carapace with postorbital spine, cervical groove 

 extending nearly or quite to dorsum. Ocular 

 peduncle with a distinct tubercle, a scale at ex- 

 ternal angle of ocular somite. Antennular pe- 

 duncle with an enlarged ciliated protuberance on 

 inner proximal margin of basal article. First 

 chelipeds with tuft of setae on propodus in both 

 sexes. Coxae from second maxillipeds to fifth legs 

 with weakly forked epipodites.  A functional 

 filamentose anterior arthrobranch on 13th somite 

 (4th leg) ; pleurobranchs behind 9th somite (3d 

 maxilliped). Exopodites on maxillipeds and legs. 

 Pleopods, except first pair, biramous. Telson with 

 well-developed terminal point and a pair of sub- 

 terminal fixed spines (Burkenroad, 1934b). 



KEY TO GENERA AND SPECIES IN THE CAROLINAS 



a. Antennular flagella hollowed out medially, chanuellike 

 in structure Solenocera atlantidis (p. 15). 



aa. Antennular flagella not hollowed out medially nor 

 chanuellike in structure 



Bymenapenaeus tropicalia (p. 15). 



14 



FISH AND WILDLIFE SERVICE 



