166 U.S. NATIONAL MUSEUM BULLETIN 271 



Beaudettiidae 



Figure 70 



Diagnosis. — Accessory flagellum 2-articulate ; mandible lacking 

 palp; inner ramus of uropod 3 reduced; coxa 4 not excavate posteri- 

 orly; telson very short, entire (but emarginate). Monogeneric. See 

 Gammaridae. 



Description. — Body like that of Gammaridae, dorsally unorna- 

 mented; rostrum obsolete; antennal peduncles elongate, accessory 

 flagellum 2-articulate; mandible with molar but lacking palp; mouth- 

 parts otherwise basic ; gnathopod 2 larger than 1 ; coxa 4 unexcavate 

 posteriorly; uropod 3 short, inner ramus half as long and one third 

 as broad as outer ramus; telson very short, entire (but emarginate). 



Relationship. — This monotypic family apparently is derived from 

 the Gammaridae. It is like the genus Elasmopus but has lost the man- 

 dibular palp, has a reduced inner ramus of uropod 3, and a short, 

 emarginate telson. 



Figure 70. — Beaudettiidae: Beaudettia palmeri J. L. Barnard (1965): a, lateral aspect; 

 b, mandible; c, lower lip; d,e, maxillae 1, 2;/, maxilliped; g, telson; h, upper lip; i, uropod 3. 



