MARINE GAMMARIDEAN AMPHIPODA 141 



Peltopes K. H. Barnard 



Peltopes K. H. Barnard, 1930. 



Type-species: P. productus K. H. Barnard, 1930 (monotypy). 



Article 2 of pereopods 3-5 expanded; gnathopod 2 simple; uropod 

 2 long; urosomite 1 elongate, dorsally keeled, process vaulting over 

 following segments; urosomite 3 not vaulting over telson; telson 

 normal; mandibular molar [unknown in type] strong, palp 3-articulate. 

 Species: 2, New Zealand, littoral. 



Stegoplax Sars 



Stegoplax Sars, 1882.— Stebbing, 1906. 



Type-species: aS*. longirostris Sars, 1882 (original designation). See 

 Sars, 1895. 



Article 2 of pereopods 3-5 expanded; gnathopod 2 simple; uropod 2 

 shortened; urosomite 1 short, unkeeled; urosomite 3 slightly vaulting 

 over telson; telson normal; mandibular molar triturative, palp 3- 

 articulate. Species: 1, N. Atlantic, bathyal. 



Ampithoidae 



Figure 61 



Diagnosis. — Accessory flagellum present or absent; telson entire, 

 short, fleshy; lower lip with anterior lobes notched or medially excavate 

 (figs. QleJ); coxa 4 not excavate posteriorly; pereopods glandular; 

 uropod 3 with very small, short rami, shorter than peduncle, rami 

 quadrate, blunt, outer armed with one or two hooks. See Isaeidae, 

 Ischyroceridae, Oedicerotidae, Calliopiidae, Pleustidae. 



Description. — Accessory flagellum varying from absent to long and 

 multiarticulate ; body smooth; rostrum absent; coxae medium in size, 

 quadrate or rounded, coxa 4 not excavate posteriorly; mouthparts 

 basic except for one genus lacking mandibular palp and another with 

 reduced molar; lower lip with lateral (outer) lobes projecting, notched 

 (bilobed) or medially excavate; gnathopods usually powerful, sub- 

 chelate, in one genus feeble and chelate, gnathopod 1 usually smaller 

 than 2, occasionally larger than 2; uropod 3 with very short quadrate 

 rami, shorter than peduncle, outer ramus armed with one or two 

 hooks; telson short, entire, nearly circular, square or triangular, fleshy. 



Relationship. — The notched outer lobes of the lower lip distinguish 

 this family from its relatives, the Isaeidae, Aoridae, Ischyroceridae, 

 and Corophiidae. The very short quadrate rami with a hook or hooks 

 on the outer are distinctive (but see Jassa in Ischyroceridae). 



