Prochaetodermatidae of the eastern Atlantic Ocean and Mediterranean Sea (Mollusca: Aplacophora)

Abstract

The Prochaetodermatidae is a family of spiculose, vermiform aplacophoran molluscs primarily of the deep-sea benthic fauna. They are ecologically important both in numbers and dominance as well as by their omnivory. In an ongoing effort, the authors are describing this significant deep-sea group from collections that have been made worldwide from continental shelves to hadal depths of > 5,000 m. Here the eastern Atlantic and Mediterranean species are described, a matter of 14 species, half of them new. The genus Prochaetoderma is here redefined and restricted with a redescription of the type species and designation of a neotype. Whereas prochaetodermatid species were first all considered as belonging to Prochaetoderma, differences in spicule morphology fall into 5 discrete genera. Herein are given precise diagnoses and a key to the following genera, accompanied by the species described here: Prochaetoderma Thiele, 1902: P. raduliferum (Kowalevsky, 1901), ?P. atlanticum new species, P. boucheti new species, P. yongei Scheltema, 1985; Chevroderma Scheltema, 1985: Ch. turnerae, Ch. gauson, Ch. scalpellum, all Scheltema, 1985; Claviderma new name: Cl. brevicaudatum new species, Cl. gladiatum (Salvini-Plawen, 1992), Cl. tricosum new species; Niteomica Ivanov, 1996b: N. hystrix new species; and Spathoderma Scheltema, 1985: S. clenchi Scheltema, 1985, S. alleni new species, S. grossum new species. In total, 3,568 specimens have been examined from depths between 50 and > 5,000 m from the West European Basin, including the Bay of Biscay, the Mediterranean Sea, and the Iberian, Cape Verde, Guinea, Angola, and Cape Basins.