First record of Nassarius fuscus (Hombron &Jacquinot, 1848) from the west coast of India, with the description of its sister species Nassarius arewarensis n. sp. (Buccinoidea: Nassariidae)

Nassarius Dumeril, 1805 is the most diverse genus within the nassariid subfamily Nassariinae. Nonetheless, information on members of this genus from the Indian subcontinent, a major ecoregion of the western Indo-Pacific, is scarce. Here, we report Nassarius fuscus (Hombron & Jacquinot, 1848) for the first time from India and provide information on its morphology and ecology. This species has previously been recorded only from the central Indo-Pacific. We also describe a new species of Nassanus, N. arewarensis n. sp., which on the basis of our data is sister to N. fuscus. Both species were found within heterogeneous strands of mangroves in the shallow intertidal area of the Aare-Ware Creek, Ratnagiri, Afaltarashtra, India. Morphological comparisons as well as species delimitation analyses using the universal cytochrome c oxidase subunit I barcode indicated that these species are distinct. The present study enhances our understanding of the species composition and the diversity of Nassarius in India.