Xiphocarididae is represented by Xiphocaris elongata; it is a very active shrimp that can be found clinging to rocks in the current or in a quiet waters. Xiphocaris is an endemic shrimp from the West Indies.

Xiphocaris elongata occurs in many diverse types of habitat on Puerto Rico, it is abundant and the presence of predators (fish and other shrimps and crabs) determine its abundance. M
ature specimens had been observed in pools at the upper reaches of El Yunque streams. Recent works from LUQ-LTER at El Verde has demonstrated that the variations in the sizes of the rostrum depend on the presence of fishes (predators). In our streams, Xiphocaris elongata is shredder feeder, he breaks the leaves and the organic matter in smaller pieces to be used by many other shrimp species, bacteria, and fungi.