MARIfTO GAMMARIDEAN AMPHIPODA 519 



Length of peduncle relative to iirosomal segment 3 ( %), to peduncles of other 



uropods ( % of peduncle of uropod 1), or to telson ( %). 

 Length of longest ramus relative to peduncle ( %). 

 Length of inner ramus to outer ( %). 



Shape of rami: styliform, lanceolate, barrel-shaped, foliaceous. 

 Articles of outer ramtis (1 or 2). 

 Minute ornamentation and hooks on rami (especially Ischyroceridae and Am- 



pithoidae) . 

 Special peduncular processes. 



TELSON 



Absence (rare) or presence. 

 Fused to urosomite S (rare) . 

 General shape and length (make sketch). 

 Length in relation to urosomite 3 ( %) or uropod 3 ( %). 

 Degree of cleft between lobes ( %), emarginate only. 



Ornamentation: apically pointed, notched, triiid, truncate, rounded, concave. 

 Greatly enlarged and with ventral keel (rare), forming dorsoventral plate. 

 Dor sovent rally thickened {"fleshy") (example, Isaeidae), bearing lateral nobs, 

 scales, hooks. 



SEXUAL DIMORPHISM 



(primarily for identification to species) 



Especially: 

 Antennae: 

 Eyes: 



Gnathopods: 

 Coxae: 



Pleonal epimera 1-3: 

 Uropod 3 : 

 Urosomal teeth: 



