On Mating Behavior of Giant Japanese Crab, Macrocheira Kaempferi DE HAAN

Abstract

Macrocheira kaempferi DE HAAN, a well-known giant crab, is an endemic species of the Japanese waters ranging from Sagami Bay southward to Kyushu. Fortunately enough, some living specimens of this crab were collected off Kamae, Kyushu, handed over to our aquarium at the end of March, 1962 and kept in a tank for display for a few months. During the time, the writer had an opportunity to observe the mating habit that had not been reported up to then. In this article, an observation on the sexual behavior of the noticeable macrocheiroid crab is described and in addition, the various postures of the pairing crab in different stages are shown by photographs.