Baenopsis, Korshunova, Tatiana, Martynov, Alexander, Bakken, Torkild, Evertsen, Jussi, Fletcher, Karin, Mudianta, I Wayan, Saito, Hiroshi, Lundin, Kennet, Michael Schroedl, & Picton, Bernard, 2017

Korshunova, Tatiana, Martynov, Alexander, Bakken, Torkild, Evertsen, Jussi, Fletcher, Karin, Mudianta, I Wayan, Saito, Hiroshi, Lundin, Kennet, Michael Schroedl, & Picton, Bernard, 2017, Polyphyly of the traditional family Flabellinidae affects a major group of Nudibranchia: aeolidacean taxonomic reassessment with descriptions of several new families, genera, and species (Mollusca, Gastropoda), ZooKeys 717, pp. 1-139 : 19

Family Baenopsis fam. n.

Diagnosis.

Body relatively wide. Notal edge discontinuous. Cerata in separate clusters on broad extensions. Rhinophores perfoliated or granulated. Anus pleuroproctic under reduced notal edge. No distinct oral glands. Radula formula 1.1.1. Rachidian teeth usually with cusp compressed by adjacent lateral denticles. Lateral teeth narrow or with attenuated process basally, denticulated or smooth. Single distal receptaculum seminis. Vas deferens long, with or without distinct prostate. External permanent penial collar absent. Penis elongated conical, internal unarmed.

Genera included.

Baenopsis gen. n., Flabellinopsis MacFarland, 1966.

Remarks.

One of the unexpected results of the present molecular analysis is the most basal position of the species Flabellina iodinea (Cooper, 1863) in relation to the families Paracoryphellidae , Coryphellidae , and Flabellinidae (Figs 1, 2). This is prima facie not very consistent with the morphological data since F. iodinea is similar to the members of the family Flabellinidae s. str. as it possesses a medium-sized body with cerata on lateral extensions. However, this may be a case of morphological convergence since F. iodinea 's relatively broad, flap-like lateral modifications of the notal edge and absence of distinct oral glands is different from the majority of the Flabellinidae s. str. Furthermore, the vas deferens in F. iodinea is considerably longer than in the taxa of the Flabellinidae s. str. On all trees obtained, Flabellina iodinea invariably appears most basally and separate from all other families. Therefore, in this case our results speak for preference of the molecular data in revealing the very separate position of this particular taxon. It is most likely that the Flabellina -like external appearance has evolved in F. iodinea independently from Flabellinidae s. str. by parallel modifications of a continuous ancestral notal edge into flap-like ceratal structures. We therefore resurrect the genus Flabellinopsis MacFarland, 1966, which was previously proposed for the species Aeolis ( Phidiana ?) iodinea Cooper, 1863. On the present molecular tree, the NE Pacific Flabellinopsis iodinea clustered together with a NE Atlantic species, " Flabellina " baetica Garcia-Gomez, 1984, in the same clade (Figs 1, 2, 7). The NE Atlantic species has ceratal and reproductive morphology somewhat similar to the genus Flabellinopsis but possesses very peculiar folded and granulated rhinophores and smooth lateral teeth (Garcia-Gomez 1984). Therefore, rather than uniting it into the genus Flabellinopsis making that morphologically not very consistent, we propose a separate new genus for Flabellina baetica (see below). The diversity of the family Flabellinopsidae fam. n. is more considerable than currently understood. On our tree, an undetermined species of " Piseinotecus " sp. appeared as possibly related to this family (Fig. 1). Furthermore, Furfaro et al. (2017) have shown that " Piseinotecus " soussi Tamsouri, Carmona, Moukrim and Cervera, 2014 (original description in Tamsouri et al. 2014) has appeared basally to " Flabellina " baetica and Facelina quatrefagesi ( Vayssière, 1888). Further investigations need to be made on these taxa.