GAMMARIDEAN AMPHIPODA 109 



1 very short (see figure), articles successively shorter, article 2 espe- 

 cially ornamented mediodistally, article 3 with small, blunt, pos- 

 terodistal process, accessory flagellum about as long as article 2 of 

 primary flagellum, broad at base, armed with 3 setae; antenna! 

 peduncular articles 2-3 and flagellar articles armed with lantern- 

 like, transparent sense organs [one of which is enlarged 5 times as 

 inset next to antenna 1 in figure, otherwise not drawn but noted by 

 arrows] ; sense organs attached alternately marginal and submarginal 

 and borne to full tip of flagellum, bases inserted in setal bundles 

 as illustrated; antenna 2 missing on 3 known specimens; inner plate 

 of maxilla 1 with 3 setae, successively smaller medio proximally; 

 maxillipedal dactyls claw-like, distally constricted, armed medially 

 with 5 short setae; coxa 1 nearly quadrate, scarcely expanded antero- 

 distally, coxae 1-3 with 1-2 large posterior spines; gnathopods 1-2 

 in each sex very similar to each other, male gnathopods slightly 

 larger and with shorter fifth articles and larger palmar spines, pos- 

 terior lobes of fifth articles poorly developed, not projecting, trape- 

 zoidal, dactyls bearing 4-5 sets of 2 setae on inner margins, each 

 pair of setae with one long and one short curved member; fifth articles 

 about 80% as long as sixth in females, about 60% in males; sixth 

 articles (hands) of male of medium expansion for genus, palms very 

 oblique, shorter than posterior margins of article 6, defining corners 

 armed with 4-5 large spines on base fine becoming increasingly 

 submarginal from proximal to distal extent; pleonal epimera 1-3 

 each with small tooth posteroventrally, posterior edges strongly con- 

 vex, in exaggerated condition on epimeron 3; telson cleft slightly 

 more than halfway. 



Holotype. — AHF No. 6030, male, 5.5 mm. 



Type locality. — Cayucos, California, July 15, 1960, intertidal 

 reef algae collected by Dr. E. Yale Dawson (as Barnard station 32). 



Material. — 3 specimens from the type locality. 



Kelationship. — This species differs from Accedomoera tricuspidata 

 (Gurjanova, 1938) and A. ushuiae (Schellenberg, 1931) in the lack 

 of dorsal body processes and from A. mokyevskii (Gurjanova, 1952) 

 by the narrower gnathopodal hands and larger rostrum. 



Among species of Pontogeneia which it closely resembles are P. 

 intermedia Gurjanova (1938, see 1951) and P. rostrata Gurjanova 

 (1938, see 1951) from which species it differs by the strongly spinose 

 defining corners of the gnathopods. In this respect it closely resembles 

 P. melanophthalma Gurjanova (1938, see 1951) but that species has 

 a smaller rostrum and a more elongated and spinose first antennal 

 article 1. Pontogeneia makarovi Gurjanova (1951) also has spinose 

 gnathopodal palmar corners and the new species may not be distinct 



