2(/) Body amphipod shaped; laterally compressed (Fig. 10) Parategastes (compressed) 



2(/) 



Body dorsoventrally compressed; cephalic shield square 



with pointed rostrum (Fig. 11); pelagic Clytemnestra 



3(1) Exopod antenna ( A^ ) at least 6 segments 

 3 ( / ) Exopod antenna ( A^) at most 4 segments 



4 (■?) Last segment endopod second leg (P. ) longer than entire exopod and usually as long as entire body 



(Fig. 12) Longipedia (fusiform nonprehensile) 



4 (3) Last segment endopod second leg (P, ) shorter than entire exopod 



10 



