GAIMMARIDEAN AMPHIPODA 43 



resembles other species of Anonyx. It is a member neither of 

 Tmetonyx^ nor of '"'■Tryphosa''' according to table 2 herein, because the 

 dactyl of gnathopod 1 has no large inner tooth and the epistome does 

 not dominate the upper lip. The inner ramus of uropod 2 is not 

 incised. Gills are not pleated as they are in typical members of 

 Anonyx but Hurley (1963) has questioned that condition as a generic 

 criterion. T met onyx nohilis is nevertheless an aberrant anonyx, in 

 that coxa 1 is unexpanded distally and its anterodistal margin is 

 obliquely rounded. Thus, it ai")proaches the minimal condition of 

 '"''Tryphosa^ Its head and prebuccal complex are not sufficiently re- 

 duced in size to assign T . nohiT/s to TJrhte^. Probably it should be 

 removed to a new subgenus created for assignment to Anonyx. If its 

 molar is asetulose then it falls into Tl'rppomedon. 



Tryphosoides falcatus Schellenberg (1931), the type and unique 

 species, was synonymized with Urhfes by J. L. Barnard (1962a), who 

 disregarded several of the characters considered to be important by 

 Schellenberg and who also at that time did not recognize the inter- 

 generic differences of mandibular molars. The molar of T. falcatus is 

 prismatic, thus apparently equivalent to stage 2 of table 1 and therefore 

 the species is not assignable to Urisfes or to any of those genera in 

 the tryphosa group of table 2. On the other hand Tryphosoides does 

 not precisely fit any of those levels of Hippoviedon in table 1 in view 

 of the distinctly shortened article 5 of giiathopod 1. Perhaps the 

 genus stands closest to Lepidepecreopsis., a member of the hippomedon 

 section which is simply a tryphosa lacking molar setules. Trypho- 

 soides parallels Lepidepecreopsis in the sense that the former is simply 

 a Tmetonyx lacking molar setules. Because the evolutionary direction 

 of molarial changes is not known one may reverse the statement and 

 say that tmetonyxes are simply species of Tryphosoides with nonpris- 

 matic, setulose molars. If Lepidepecreopsis were to be retained as a 

 valid genus then so must Tryphosoides^ because the latter has several 

 other characters of at least subgeneric value : e.g., a reduced accessory 

 fiagellum. Because the dactylar tooth of gnathopod 1 is very small 

 and because the head may be small (unclear) and coxa 1 is inter- 

 mediate between that of Tmetonyx (s.str.) and ^''Tryphosa^'' Trypho- 

 soides falcatus stands close to Uristes and might be said to be a Uristes 

 lacking molar setules. Thus, Tryphosoides should be retained at 

 least in subgeneric status with Uristes until a monographer of the 

 Uristidinae can determine its true affinities. 



242-332—67 4 



