GAMMARIDEAN AMPHIPODA 13 



peduncle; peduncle of uropod 3 short, flat, rami longer than peduncle, 

 outer slightly longer than inner and bearing minute, barrel-shaped 

 article furnished with two long setae attached near base of article 2 ; 

 telson short, broad, with cornified lateral lobes, each armed with three 

 setae, posteroventral margin of telson rounded, posterodistal margin 

 slightly excavate. 



HoLOTYPE. — AHF No. 6129, male, 6.0 mm. Unique. 



Type-locality.— Station 7234, 27°38'00" N, 115°16'16" W, Y91- 

 842 m, Jan. 2, 1961. 



Relationship. — This species differs from its close relative, Lemhos 

 longidigitans (Bonnier, 1896), from the bathyal of the northeastern 

 Atlantic Ocean, by having a more slender mandibular palp article 3, 

 which is not falciform and has a distinct setal arrangement, by the 

 longer mandibular palp article 2, the blunt, hemi-oval coxa 1, the 

 slender article 2 of pereopod 3, the more slender article 6 of pereopod 

 1 ( ? and 2) and possibly by the slight differences in pleonal epimera 

 1 and 2. The lateral cephalic lobe of L. edentulus apparently is better 

 developed than that of L. longidigitans. 



Lemhos lohata J. L. Barnard (1962a), the only other deep-sea 

 species of Lemhos (abyssal of southeast Atlantic Ocean), has a nar- 

 rower cephalic lobe than does L. edentulus., a longer mandibular palp 

 article 3 and a smaller distoventral process of the peduncle of 

 uropod 2. 



The three deep-sea species of Lemhos differ from 27 known shallow- 

 water species by the reduced inner plate of maxilla 1, the small coxae, 

 the absence of eyes and the short, broadly expanded peduncle of uro- 

 pod 3. Male gnathopod 1 of shallow-water species usually is well 

 developed and ornamented differently in the several species, but the 

 three deep-sea species have a poorly developed first gnathopod : that 

 of L. lohata is very youthful in appearance; that of L. edentulus is of 

 intermediate modification; and only that of L. longidigitans has an 

 ornamented palm; however, gnathopod 1 of the latter species is not 

 greatly enlarged. In contrast to other species of the genus, L. eden- 

 tulus has a minute second article on the outer ramus of uropod 3. The 

 three deep-sea species may constitute a new genus. 



Lemhos lohata and L. edentidus are remarkable species of Lemhos 

 in which the article 2 of pereopod 3 is unexpanded, but L. longldigltajns., 

 otherwise similar to the above taxa, has an expanded second article. 



