Reidentification of Volutopsius hirasei and its implications for the taxonomy of the genera Fusivolutopsius and Habevolutopsius (Gastropoda: Buccinidae: Volutopsiinae)

The identity of Volutopsius hirasei Pilsbry, 1907, the type species of Fusivolutopsius Habe & Sato, 1973 and Habevolutopsius Kantor, 1983, has long been confused because of conflicting interpretations based on material from geographically disparate localities. In this study, the taxonomic identity of V. hirasei is clarified through examination of the holotype and newly obtained specimens from off northeastern Honshu (Sanriku), Japan, including waters in the vicinity of the type locality. The radular morphology of these specimens closely agrees with that illustrated by Habe & Sato (1973), confirming the validity of Fusivolutopsius. Re-examination of material identified as V. hirasei by Kantor (1983a) demonstrates that it represents a distinct, previously undescribed species, here described as Habevolutopsius kantori sp. nov. Because the type species designation of Habevolutopsius was based on a misidentification, Article 70.3.2 of the International Code of Zoological Nomenclature is applied to fix as the type species the taxonomic species actually involved in the misidentification, here named H. kantori sp. nov. Furthermore, specimens referred to V. hirasei by Masuda & Habe (1987) are shown to be conspecific with Volutopsius diminutus Dall, 1919, previously regarded as a junior synonym of V. hirasei. This species is recognized as valid and transferred to Habevolutopsius. Consequently, Fusivolutopsius is confirmed as a valid genus, Lussivolutopsius Kantor, 1983 is placed in its synonymy, and the taxonomic composition of Habevolutopsius is revised. This study resolves the long-standing taxonomic confusion surrounding V. hirasei and provides a revised framework for the classification of Volutopsiinae in the northwestern Pacific.