Designation of a neotype for the dwarf sea hare Aplysia concava G. B. Sowerby I, 1833, and a review of the status of Aplysia norfolkensis G. B. Sowerby II, 1869 (Mollusca: Heterobranchia)

Abstract

A recent revision of the globally distributed dwarf sea hare Aplysia parvula sensu lato split that species into 10 separate taxa. As Australian specimens were not included in this revision, further study using material from the south west Pacific was warranted. At least one described species, Aplysia concava, was found to occur in southeastern Australia, New Zealand and New Caledonia. A redescription of this species was published by Nimbs & Wilson (2021) even though the holotype was deemed lost—the difficulty, in 2020–2021, to access important and relevant museum specimens, prevented the designation of an appropriate neotype at that time. The present study is an annexure to the published redescription for the purpose of designating a neotype for Aplysia concava and provides a discussion on the taxonomic status of another dwarf sea hare species, Aplysia norfolkensis, which is herein regarded as a junior synonym of A. concava.