A new solitary free-living species of the genus Sphenopus (Cnidaria Anthozoa Zoantharia Sphenopidae) from Okinawa-jima Island Japan

摘要

A new species of free-living solitary zoantharian is described from Okinawa, Japan. Sphenopus exilis >sp. n. occurs on silty seafloors in Kin Bay and Oura Bay on the east coast of Okinawa-jima Island. Sphenopus exilis >sp. n. is easily distinguished from other Sphenopus species by its small polyp size and slender shape, although there were relatively few differences between Sphenopus exilis >sp. n. and Sphenopus marsupialis in the molecular phylogenetic analyses. Currently, very little is known about the ecology and diversity of Sphenopus species. Thus, reviewing each species carefully via combined morphological and molecular analyses by using newly obtained specimens from type localities is required to clearly understand and distinguish the species within the genus Sphenopus.