Sea Stars of Families Ophidiasteridae and Goniasteridae (Echinodermata: Asteroidea) from the Mesophotic Zone of the Ogasawara Islands, Including Two New Species

Abstract

Five species of sea stars of the families Ophidiasteridae and Goniasteridae including two new species, Bathyferdina caelator sp. nov. and Fromia labeosa sp. nov., were collected by dredging from the mesophotic zone of the Ogasawara Islands, Japan. Bathyferdina caelator is distinguished from B. aireyae Mah, 2017 by the presence of glassy bosses (crystal bodies) on actinal and adambulacral plates and the absence of them on marginal plates. Fromia labeosa has large, elliptical pedicellariae on the actinal plate and is further distinguished from its congeners based on characters of the abactinal and superomarginal plates, granules, actinal papulae, furrow spines, and the subambulacral spines. We also provide descriptions for three mesophotic species, Fromia eusticha Fisher, 1913, Ogmaster capella (Müller and Troschel, 1842), and Tamaria tenella (Fisher, 1906), which are poorly studied in Japanese waters.