Hexabranchus morsomus Marcus & Marcus, 1962

Tibiriçá, Yara, Pola, Marta, Pittman, Cory, Gosliner, Terrence M., Malaquias, Manuel A. & Cervera, Juan Lucas, 2023, A Spanish dancer? No! A troupe of dancers: a review of the family Hexabranchidae Bergh, 1891 (Gastropoda, Heterobranchia, Nudibranchia), Organisms Diversity & Evolution (New York, N. Y.) 23 (4), pp. 697-742 : 735

Hexabranchus morsomus Marcus & Marcus, 1962

Description notes Description based on preserved material with a short note on the living specimen, internal morphology, and external morphology; only radula and reproductive system illustrated: size 30 mm (preserved); notum bright red and cream (alive); dorso-ventral swimming behavior; body smooth, broad (preserved); large crenate oral tentacles; six tripinnate gill leaves around an elevated anal papilla; reproductive system with two genital openings; radula formulae 40 × 90.1.90; rachis rudimentary and triangular.

Own conclusion/opinion on its taxonomic status Thompson (1972) stated that the geographic distribution and radula details were the only relevant distinguishing characteristics between this species and Indo-Pacific Hexabranchus spp. Despite this comment, he did not explicitly define his position regarding the taxonomic status of H. morsomus which remained uncertain until Valdés (2002) confirmed it as a valid species (which is further verified by our molecular analysis).