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) Author Korshunova, Tatiana Author Martynov, Alexander Author Bakken, Torkild Author Evertsen, Jussi Author Fletcher, Karin Author Mudianta, I Wayan Author Saito, Hiroshi Author Lundin, Kennet Author Michael Schroedl, Author Picton, Bernard text ZooKeys 2017 717 1 139 http://dx.doi.org/10.3897/zookeys.717.21885 journal article http://dx.doi.org/10.3897/zookeys.717.21885 1313-2970-717-1 C19B43B1B3214CB1B1B2A246CEAC56BC C19B43B1B3214CB1B1B2A246CEAC56BC Family Samlidae fam. n. Diagnosis. Body narrow. Notum discontinuous. Cerata in separate clusters, on elevations. Rhinophores perfoliated. Anus pleuroproctic under the reduced notal edge or mixed (pleuroproctic in higher acleioproctic position). Distinct oral glands present, commonly penetrate below anterior cerata. Radula formula 1.1.1. Rachidian teeth usually with strong cusp, only rarely compressed by adjacent lateral denticles. Lateral teeth denticulated narrow or with attenuated process basally. Distal and proximal receptaculum seminis or only proximal receptaculum. Vas deferens usually short, with indistinct prostate. External permanent penial collar absent. Penis in many cases conical, narrow, always internal and unarmed. Genera included. Luisella gen. n., Samla Bergh, 1900. Remarks. The genus Samla and related taxa were invariably considered as synonyms of the traditional genus Flabellina throughout all the recent history of nudibranch taxonomy (e.g., Gosliner and Griffiths 1981 ; McDonald 2009 ). Previously it was listed sometimes as valid (e.g., Burn 1964 ) but without detailed discussion. However, the Indo-Pacific tropical genus Samla differs morphologically from the Flabellinidae s. str. in the absence of compound stalks, often non-compressed cusp of the rachidian teeth, and also by having a short vas deferens. The present molecular phylogenetic analysis not only confirmed such disparate morphology from true Flabellinidae , but also revealed a very profound problem: species of the genus Samla and some related taxa are basal to the Aeolidacea as a whole and the major complex of aeolidacean families, including Aeolidiidae , Facelinidae , Tergipedidae , and Eubranchidae , rendering the Flabellinidae polyphyletic! Such topology with minor variations has appeared invariably on all trees obtained in the present analysis and was hinted at as soon as Flabellina babai was sequenced ( Carmona et al. 2011 ). This result is of great importance because it clearly implies that 1) Understanding of the real phylogenetic and taxonomic patterns of the traditional " Flabellinidae " is possible only with inclusion of all major families of the nudibranch suborder Aeolidacea in the analysis, as is performed in the present study, and 2) The traditional " Flabellinidae " cannot be by any means maintained as single family, but must be separated into several smaller morphologically and molecularly consistent families (Fig. 2). Therefore, the genus Samla Bergh, 1900 ( Bergh 1900b , 1908 ) is resurrected and the new family Samlidae is established here. Apart from the taxa that belong to the genus Samla , which are clustered in a compact clade (Figs 1, 2, 45) the species Flabellina babai Schmekel, 1972 appears as a closely related clade. Flabellina babai differs considerably from Samla including the character of a distinct granulated prostate ( Schmekel 1972 ; Schmekel and Portmann 1982 ), unique for the majority of the Paracoryphellidae , Coryphellidae and Flabellinidae . This feature is so far known only for the paracoryphellid genus Chlamylla , which is dramatically different from Flabellina babai externally. Therefore, a new genus for F. babai , Luisella gen. n., is proposed here (see below).