70 U.S. NATIONAL MUSEUM BULLETIN 292 



on the island, where the Httoral areas are not continuously abraded 

 by swift currents. In this area of the river, floating coconut husks 

 are frequented by this slirimp, and in those husks that have been in 

 the water for several days, a few individuals are almost always present. 



Distribution. — West Indies and Republic of Costa Rica (?) (Cuba, 

 Jamaica, Puerto Rico, Dominica, Barbados). Jonga was believed to 

 be a West Indian endemic until we received from D. P. Kelso speci- 

 mens of J. serrei or a closely related species collected in the vicinity 

 of Tortuguero, Costa Rica, in 1963 and 1964. 



Dominica Stations: 13-15, 18, 54, 56, 57, 62, 67, 71, 72, 78, 80, 81, 

 84 (0-1,500 ft.). 



Remarks. — There is no doubt that this little shrimp is genericaUy 

 distinct from the species of Poiimirim. It is distinguished not only by 

 the denticulate orbital margin but also by the unique appendix mas- 

 culina on the second pleopod of the male. Of aU of the American atyids, 

 it seems to resemble most closely the species of Caridina, which are so 

 numerous and so widespread through most of the tropical regions of 

 the world except the Americas. 



Jonga serrei was collected on Dominica only in February, March, 

 and April; ovigerous females were well represented in all three months. 



Genus Micratya 



10. Micratya poeyi (Guerin-Meneville) 



Figures 12, 13, 14th, i 



Atya Poeyi Gu6rin-M6neville, 1855, pi. 2: figs. 7, 7a-c [type-locality: CubaJ 



Calmania Poeyi. — Bouvier, 1909, p. 335. 



Micratya Poeyi.— Bouvier, 1913, p. 181; 1925, p. 325, figs. 709-716. 



Micratya poeyi. — Schmitt, 1935, p. 137, fig. 11. 



Micratyia poeyi. — V61ez, 1967, p. 42. 



Micraitya poeyi. — V61ez, 1967, p. 42. 



Diagnosis. — Orbital margin unarmed. Rostrum with dorsal teeth, 

 ventral margin with one or two teeth but not finely serrate. Ventral 

 margins of abdominal pleura unarmed. Eyes not reduced. Basal 

 segment of antennular peduncle without dorsal spines proximal to 

 series bordering distal margin. Pereiopods without exopods. Fingers 

 of chelae of first and second pereiopods bearing terminal tufts of 

 long hair. Carpus of second pereiopod very slightly longer than broad. 

 Last three pereiopods armed with sharp spines, but \\dthout horny 

 scales or tubercles. Merus of third pereiopod not much broader than 

 that of fourth. Appendix masculina on second pleopod of male ex- 

 tending far beyond end of appendix interna and armed only with terminal 

 cluster of long, stout spines. A small species, maximum postorbital 

 carapace length little more than 6 mm. 



