MARINE GAMMARIDEAN AMPHIPODA 



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Figure 1.— BASIC GAMMARIDEAN, part I, lateral aspect. Note the following char- 

 acteristics of the basic gammaridean: elongate antennal peduncles; head of medium 

 size, rostrum small or obsolete; eyes when present paired, lateral, composed of ommatidia 

 and lacking cuticular lenses; accessory flagellum raultiarticulate; coxae 1-4 subequal to 

 each other in size, subquadrate in outline, coxa 4 posteriorly excavate; gnathopod 2 equal 

 to or larger than gnathopod 1; no articles of pereopods 1-2 differentially elongated; 

 pereopods 3-5 subequal to each other in length; all body segments free; uropods all 

 biramous, no uropod elongated; telson free. See diagnosis. 



