DECAPOD CRUSTACEANS OF THE WEST INDIES 37 



Macrobrachium jelskii and Palaemon pandaliformis were not found 

 on Dominica, but elsewhere in the Antilles they occur in habitats 

 similar to those of Jonga serrei and M. acanthurus. On other islands 

 having larger rivers or streams \vith a low gradient, all four range 

 much farther inland than do the latter two on Dominica. The habitat 

 of Glyptograpsus is not known except that it was found in "fresh 

 water" on Jamaica. Hartnoll (1965) did not encounter it during his 

 studies of the grapsid crabs of that island. 



Of the three species of the genus Sesarma herein classified as "fresh- 

 water species that invade marine habitats," ecological data are avail- 

 able for only S. roberti. Hartnoll (1965) presented an excellent, but 

 brief, account of this species (= his S. angustipes) on Jamaica. On 

 Dominica, this crab ranges upstream for a distance of at least 

 two miles, where it even invades seepage areas. 



There are 28 decapods in the Antilles that are believed to complete 

 their Ufe cycles in fresh water. Among them is the Jamaican Metapaulias 

 depressus, which frequents bromeliads. This decapod is one of few 

 that invade aerial habitats and is the only one known to be so re- 

 stricted. On Jamaica it lives at elevations of 800 to 2,700 feet (Hartnoll, 

 1964; see also Laessle, 1961) and surpasses adaptations made by other 

 crabs that frequent trees in that it completes its life cycle well above 

 the surface of the ground. 



Although freshwater lakes are comparatively rare in the Antilles 

 and few have been examined for then* decapod fauna, Boeri Lake — and 

 probably Freshwater Lake — on Dominica is inhabited by Gainotia 

 dentata. Freshwater swamps and pools on Cuba ai'e frequented by the 

 crayfish Procambarus cubensis cubensis, which is by no means con- 

 fined to such habitats but also lives in many of the smaller streams 

 on the island and on Isla de Pinos. 



Among the stream inhabitants in the West Indies are both cray- 

 fishes belonging to the genus Procambarus (Cuba and Isla de Pinos) 

 and crabs belonging to the genera Epilobocera (Cuba, Isla de Pinos, 

 Hispaniola, Puerto Rico, and Saint Croix), Guinotia (Lesser Antilles), 

 Pseudothelphusa (Cuba and Hispaniola), Trichodactylus (Trinidad), 

 and Sesarma bidentatum (Jamaica). Little is known of the ecological 

 distribution of most of these species, and data for Epilobocera granulata 

 are totally lacking. Since all other members of the genera Epilobocera, 

 Guinotia, and Trichodactylus occur in fresh water, this species also is 

 assumed to do so. Furthermore, it is suspected that all of these occur 

 in or in the immediate vicinity of streams. Hartnoll (1964) indicated 

 that Sesarma bidentatum occurs on Jamaica at altitudes of 1,200 to 

 4,500 feet and is present in several river systems, where it frequents 

 the clear waters of very small streams, small rivers, and even a stream 

 flowing through a cave. This crab was found in pools and shallow 



