Microphrys Bicornutus (Latreille, 1825): The Complete Larval Development Under Laboratory Conditions with Notes on Other Mithracine Larvae (Decapoda: Brachyura: Majidae)

Abstract

ABSTRACT The complete larval development, consisting of two zoeal stages and a megalopa, and the first crab stage is described for the shallow-water western Atlantic spider crab Microphrys bicornutus. Data from laboratory cultures indicate that the species can complete its planktonic development in less than a week, and is able to attain first crab stage in as few as 10 days. The zoeal stages of M. bicornutus show a great many similarities to known zoeae in other genera within the subfamily Mithracinae, including species of the American genus Mithrax, and to Mucrocoeloma, and to a lesser extent the Indo-West Pacific genera Tiarinia and Micippa. Morphological features shared among both the zoeal and megalopal stages of the various mithracine genera are compared, and phylogenetic relationships within Microphrys, Mithrax, and Macrocoeloma are proposed.