Abstract
An integrative taxonomy approach of the Indo-Pacific deep-water genus Vermeijius Kantor, Fedosov, M.A. Snyder & Bouchet, 2018 (Neogastropoda: Buccinoidea: Fasciolariidae) revealed a significant radiation, with molecular (cox1 barcode fragment) and morphological data supporting species delimitation and the status of the genus. A total of 40 species is recognized, of which 27 are described as new, namely V. abditus sp. nov., V. admirabilis sp. nov., V. albulus sp. nov., V. antea sp. nov., V. atimovatae sp. nov., V. bellatulus sp. nov., V. brevicostatus sp. nov., V. celatus sp. nov., V. chinoi sp. nov., V. comorensis sp. nov., V. corbariae sp. nov., V. costuliferus sp. nov., V. cracens sp. nov., V. fijiensis sp. nov., V. geminatus sp. nov., V. macdonaldensis sp. nov., V. mainbaza sp. nov., V. malampaensis sp. nov., V. miriky sp. nov., V. papuaensis sp. nov., V. pauxillus sp. nov., V. putillus sp. nov., V. sayaensis sp. nov., V. snyderi sp. nov., V. spectabilis sp. nov., V. tarasoc sp. nov., and V. tashiensis sp. nov. Five new combinations are established: Vermeijius aikeni (Lussi, 2014), V. alcyoneum (Hadorn & Fraussen, 2006), V. brinkae (Lussi, 1996), V. inglorius (Hadorn & Fraussen, 2006), and V. thielei (Schepman, 1911). The radula is variable interspecifically and not genus specific, and is similar to those of other genera, e.g., Granulifusus Kuroda & T. Habe, 1954 and Amiantofusus Fraussen, Kantor & Hadorn, 2007. The genus is confined, with few exceptions, to the upper bathyal zone, occurring at depths between 80 and 1200 m, with most records from 300–800 m. The highest species richness (10 species) was recorded in Madagascar and the Mozambique Channel, followed by New Caledonia (8 species), Papua New Guinea and the Solomon Islands (6 species). This pattern likely reflects more intensive sampling of the upper bathyal zone in these regions compared to other parts of the Indo-Pacific.