KEY TO SUBORDERS, SECTIONS, SUPERFAMILIES, AND FAMILIES OF DECAPOD 

 CRUSTACEANS FOUND IN THE CAROLINAS 



a. General form shrimplike; abdomen well developed and usually with carapace compressed; pleopods always present 



in full number and used for swimming Suborder Natantia (p. 14) . 



b. Pleura of second abdominal segment not overlapping those of first segment Section Penaeidea (p. 14). 



c. First three pairs of legs chelate, all five pairs of legs well developed Family Penaeidae (p. 14). 



cc. First three pairs of legs chelate, last two pairs of legs small or wanting Family Sergestidae (p. 38). 



bb. Pleura of second abdominal segment overlapping those of first segment Section Caridea (p. 41). 



c. First pair of legs chelate or simple. 



d. Fingers of chelae on first and second legs slender, cutting e Iges all pectinate Family Pasiphaeidae (p. 41). 



dd. Fingers of chelae on first and second legs variable in thickness; cutting edges of fingers of chelae not all 

 pectinate, 

 e. Carpus of second pair of legs entire; first pair of legs always with well-developed chelae. 



f. Third pairs of maxillipeds pediform; body slender in most species Family Palaemonidae (p. 42). 



fT. Third pair of maxillipeds broad, leaflike; body short and thick Family Gnathophyllidae (p. 61). 



ee. Carpus of second pair of legs usually subdivided into two or more joints; first pair of legs often asymmetrically 

 chelate. 



f. Chelae of first pair of legs distinct, at least on one side, 

 g. Each of first legs chelate. 



h. Eyestalks short, usually covered by carapace; first pair of legs stronger than second 



Family Alpheidae (p. 62). 

 hh. Eyestalks medium length or long, not covered by carapace; first pair of legs not stronger than second 

 pair, 

 i. Rostrum small or wanting; eyestalks long, slender; first two pairs of legs subequal 



Family Ogyrididae (p. 74). 

 ii. Rostrum well developed; eyestalks not abnormally lengthened; second pair of legs usually longer 



or stronger than first Family Hippolytidae (p. 76). 



gg. Only one of first pair of legs chelate, opposite leg ending in a simple clawlike dactyl 



Family Processidae (p. 86). 



fT. Chelae of first pair of legs microscopically small or absent Family Pandalidae (p. 87). 



cc. First pair of legs subchelate Family Crangonidae (p. 88). 



aa. General form lobsterlike or crablike; abdomen either well developed or greatly reduced in size, usually with abdomen 



and carapace depressed; pleopods reduced or absent, not used for swimming Suborder Reptantia (p. 90). 



b. Abdomen extended, symmetrical, with well-developed tail fan Section Macrura (p. 90). 



c. Abdomen well armed, pleura well developed; third pair of legs like first Superfamily Scyllaridea (p. 90). 



d. Body subcylindrical; antennae with strongly developed flagella Family Palinuridae (p. 91). 



dd. Body strongly depressed; antennae short, squamiform Family Scyllaridae (p. 94). 



cc. Abdomen more or less membranous; pleura small or wanting; third legs unlike first, never chelate 



Superfamily Thalassinidea; 

 Family Callianassidae (p. 99). 

 bb. Abdomen bent upon itself or flexed beneath thorax; pleura usually small or wanting; tail fan variable in develop- 

 » ment; (third pair of legs unlike first, never chelate). 



c. Uropods usually present, often reduced in size, sometimes united with telson; last thoracic sternite free; carapace 



not apparently fused with epistome Section Anomura (p. 104). 



d. Abdomen well developed. 



e. Abdomen symmetrical, more or less flexed beneath thorax; body depressed; tail fan well developed 



Superfamily Galatheidea (p. 104). 



f. Form somewhat lobsterlike; rostrum well developed Family Galatheidae (p. 104). 



ff. Form crablike (Euceramus elongate) ; rostrum short and broad or wanting-. Family Porcellanidae (p. 106). 

 ee. Abdomen asymmetrical; tail fan reduced and adapted for holding body in hollow objects 



Superfamily Paguridea; Family Paguridae (p. 114). 



dd. Abdomen much reduced in size and flexed under thorax Superfamily Hippidea (p. 136). 



e. First pair of legs subchelate; carapace depressed Family Albuneidae (p. 136). 



ee. First pair of legs simple; carapace subcylindrical Family Hippidae (p. 139). 



] 2 FISH AND WILDLIFE SERVICE 



