Abbreviated development in a pinnotherid crab

Abstract

ATKINS1 has described the post-embryonic development of two British species of Pinnotheres. In P. pisum there are four zooeal stages and one megalopa, and in P. pinnotheres there are two zooeæ and a megalopa. In P. pisum the megalopa stage was reached six weeks after spawning and in P. pinnotheres it was reached after an interval of 21-26 days. Atkins quotes Sandoz and Hopkins2 and Hart3 to the effect that P. ostreum takes 21 days from hatching to megalopa and P. taylori 28 days from hatching to young crab. © 1960 Nature Publishing Group.