Hexabranchus giganteus, Tibiriçá & Pola & Pittman & Gosliner & Malaquias & Cervera, 2023

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 : 726

Can a Hexabranchus species still be undescribed?

Below we provide a commented list of all Hexabranchus species described so far including our reasons to allocate synonyms under each species here considered valid. This section provides a solid base to justify the introduction of a further species, as well as a tool to revise potential morphotypes not examined by us. Surprisingly, H. giganteus sp. nov. did not match any described Hexabranchus spp. This is likely due to its depth range (usually below 30 m) and to confusion in the literature. Overall, color pattern and notun texture associated with life stages were good indicators for species identification. Externally, H. giganteus sp. nov. differs from all other Hexabranchus species by its color combination, higher number of rhinophore lamellae, and outstanding size when adult. Internally, H. giganteus sp. nov. clearly differs by a much shorter deferent duct (Fig. 26).