The genus Aspidosiphon Diesing, 1851 (Sipuncula: Aspidosiphonidae): description of a new shell dwelling species, notes on Aspidosiphon (Paraspidosiphon) laevis de Quatrefages, 1866 and current status from India

Sipuncula is one of the most taxonomically neglected groups of marine invertebrates in Indian waters. Research on these worms has been stagnant for the last three decades as there are no sipunculan taxonomists in India. The current work is an attempt to resurrect taxonomic research on Indian Sipuncula fauna by describing the first new Sipuncula species from Indian seas. A new molluscan shell dwelling species, Aspidosiphon (Akrikos) carnicobarensis sp. nov., is described from Car Nicobar Island, India collected from 205 m depth. The new species is characterized by the presence of scattered unidentate hooks, a thick and well-developed anal shield with deep grooves, flattened papillae on the trunk, and warts on the posterior trunk. Aspidosiphon (Paraspidosiphon) laevis de Quatrefages, 1866 is reported along with the first colored photographs from India and notes about its taxonomic status. The paper additionally reviews the present status of all the species in the genus Aspidosiphon from India, revising them in accordance with the current classification.