Albania formosa Collingwood, 1881

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 : 733

Albania formosa Collingwood, 1881 (Fig. 26S)

Description notes Description of a single specimen, observed alive; only external morphology provided: length 50 mm; mantle extended on the side, able to roll; rhinophores thick, without sheath, non-retractile; seven gill tufts separated in individual cavities within a common, delicate ring; background color pale red, darker on the central notum; red “forms” on the side with minute whitish dots forming shapes; oral tentacle crenated; foot extending beyond mantle.

Own conclusion/opinion on its taxonomic status the genus Albania Collingwood (1881) was created to accommodate species closely related to the genus Hexabranchus but with seven retractile gill tufts. The author includes a note of its swimming behavior as typical of Hexabranchus spp. No specimens handled by us fully retract their gills, but they were able to contract them when disturbed and (in a juvenile) within the major cavity. The apparent odd gill arrangement is typical of a juvenile Hexabranchus . This species matches H. sanguineus from the West Pacific in the illustrated pattern. The inner margin of the lateral red band is strait rather than undulating, the lateral patches are truncated medially and elongated laterally and there are several disjunct, round patches between them. Together, these markings are very different from typical H. lacer . The pencil stippling on the notum corresponds to the dense patches of minute white flecks that are also characteristic of H. sanguineus , West Pacific morphotype. The rhinophores appear slenderer and the gills more sparsely branched than what is commonly seen in H. lacer . Seven gill branches are within the range of variation for H. sanguineus and H. lacer .

The overall appearance suggests that this species is a junior synonym of H. sanguineus .