NO. 9 manning: Atlantic stomatopod Crustacea 31 



with a dark patch ; crest and bases of marginal teeth of telson are dark ; 

 there is a black patch on anterior half of telson either side of the crest; 

 uropods with prominent line of dark pigment on dorsal surface of 

 penultimate segment of outer branch, with entire distal segment of outer 

 branch black; distal half of inner branch of uropods black; merus of 

 raptorial claw with a line of dark pigment on upper, lower, and anterior 

 margins of outer face. 



Genus Lysiosquilla Dana, 1852 



The two species described below bring the number of western At- 

 lantic species in this genus to 10. Chace (1958) commented upon the 

 heterogeneity of the genus and reviewed the possible evolution of the 

 telson in the western Atlantic. In his key to the eight species from that 

 area, the present new species would both fall near L. grayi Chace, 1958. 



In addition to these two new species, L. grayi, L. chilensis Dahl, 

 1954, and L. decemspinosa Rathbun, 1910, are the only other known 

 species in the genus which lack the mandibular palp and the papillae on 

 the antennal protopod, and in which a reduction in the number of epi- 

 pods occurs. Schmitt (1940) gave a partial list of species of Lysio- 

 squilla which have one or more papillae on the antennal protopod. The 

 importance of these characters at the generic level will not be known 

 until the entire genus is surveyed. 



Key to the Species of Lysiosquilla From the Atlantic Coast 

 OF Northern South America 



1. Ventral surface of telson without submarginal spines; posterior 

 marginal spines immovable; mandibular palp present .... 2 

 Ventral surface of telson with submarginal spines, the submedian 

 pair movable; mandibular palp absent 3 



2. Abdomen unarmed; raptorial dactylus armed with five or six 



teeth [L. 



glabriuscula (Lamarck, 1818) ; Brazil, Lemos de Castro, 1955] 

 Posterior margin of fifth and sixth abdominal somites spinous; 

 raptorial dactylus armed with eight to twelve teeth . . . [L. 

 scabricauda (Lamarck, 1818) ; Brazil, Lemos de Castro, 1955] 





