Abstract
Larvae of crab species inhabiting the shallow water marine environment show a wide range in nutritional requirements that must be satisfied via the diet. The present study compares the dietary requirements of larvae of the deep sea red crab G. quinquedens Smith with those of the stone crab M. mercenaria Say, a shallow water species. Stone crab larvae cannot survive to metamorphosis on a rotifer diet. Red crab larvae show no difference in survival to metamorphosis on rotifer and brine shrimp nauplius diets althouth some delay in development is seen on the former diet. Increased nutritional flexibility exhibited by the red crab may be related to its deep water habitat and evolution of such flexibility may be required for penetration of that habitat.