Asthenosoma marisrubri n.sp. (Echinodermata, Echinoidea) from the Red Sea

Indopacific echinoids of the genus Asthenosoma that have hitherto been described as A. varium actually belong to two distinct species that are geographically separated. Animals of the eastern population, extending from Sri Lanka to Hawaii and centered around the Indonesian Archipelago and the Philippines are A. varium Grube, 1868. The new species, A. marisrubri, is so far known only from the northern Red Sea. The two species can be clearly distinguished by the distribution and the nature of the aboral spines and by the lack of tridactylous pedicellariae with blunt massive valves in A. marisrubri n.sp.