Morphology of the megalopa and first crab instar of the Shamefaced Crab Calappa granulata (Crustacea, Brachyura, Calappidae)

Abstract

An unknown large megalopa was captured alive in a plankton sample taken south of Eivissa (Balearic Islands) in the western Mediterranean. The juvenile was obtained after moulting of the megalopa in the laboratory. The morphology of the first crab stage allowed the identification of the megalopa as belonging to the species Calappa granulata. Heterochely with right handedness is already evident in the megalopa stage. Its morphological characters are compared with those of the other known megalopae of related species.