Lecithotrophic Larval Development of the Spider Crab Goniopugettia Sagamiensis (Gordon, 1931) (Decapoda, Brachyura, Majidae) Collected from the Continental Shelf Break

Abstract Larval stages of the spider crab Goniopugettia sagamiensis (Gordon, 1931) (subfamily Epialtinae) collected from the continental shelf break are described based on laboratory-reared materials. Larval development of G. sagamiensis consists of two zoeal and one megalopal stage as typical in majid crab larvae. It took 31–35 days from hatching to the crab 1 stage at 14.1–18.5°C. The diameters of eggs of the present species are relatively large (1.04–1.24 mm), and the larvae have a mass of yolk granules throughout the larval stages. The larvae metamorphosed into the crab 1 stage without feeding. Such a lecithotrophic development as found in the present species is only known in Chlorinoides longispinus (De Haan, 1839) (subfamily Majinae) among the majid species of Japan. General morphology of the zoeal stages of G. sagamiensis is similar to C. longispinus, for example, the rudiment of the mandibular palps in the zoea 1 stage.