Flabellinoidea Bergh, 1889

Superfamily Flabellinoidea Bergh, 1889 , reinstated

( Fig. 1, 2; Tables 1–3)

‘Tribe Pleuroprocta’ part. Odhner 1939: 50–3.

Diagnosis: Aeolidacean superfamily with triserial radula. Notal edge commonly present, either continuous or discontinuous, more rarely almost completely reduced. Cerata are not placed in regular rows, but are placed either in continuous, irregular rows, or discontinuous groups, or may be placed on stalk-like notal derivation in correlation with a continuous or discontinuous notal edge. Anus commonly pleuroproctic, rarely mixed pleuroproctic toward acleioproctic/cleioproctic position. Anterior foot corners commonly present. Elaborate oral glands commonly absent, more rarely present. Masticatory edges of jaws in many taxa bear several rows of compound, sharpened or tubercle-like denticles. Both proximal and distal seminal receptaculums are commonly present, more rarely reduced to single one. Clasping organ in female part of reproductive system absent. Vas deferens more commonly moderately long, but can be also very short, prostate indistinct or distinct, including highly elaborated one. Supplementary gland or usual accessory glands are completely absent. The only known example of a wellpronounced accessory gland protruding from the penial base is in the genus Occidenthella of the family Coryphellidae , which was formed completely independently from the superfamilies Fionoidea and Aeolidioidea . Massive external permanent penial collar present in the genus Chlamylla of Paracoryphellidae , commonly absent. External penis present in the genus Paracoryphella of Paracoryphellidae , commonly penis internal, devoid of any cuticular structures.

Families included: Paracoryphellidae Miller, 1971 , Flabellinidae Bergh, 1889 , and Coryphellidae Bergh, 1889 .

Remarks: The superfamily Flabellinoidea Bergh, 1889 is reinstated here following our molecular phylogenetic analysis, which robustly places the core triserial families Flabellinidae Bergh, 1889 , Paracoryphellidae Miller, 1971 , and Coryphellidae Bergh, 1889 into a highly supported monophyletic group ( Figs 1, 2). The superfamily Flabellinoidea is solely comprised of triserial families without confirmed exceptions so far. Most of the taxa of the superfamily Flabellinoidea possess a notal edge that is continuous, discontinuous, or modified into stalks, and the reproductive system is devoid of any cuticular stylets. Supplementary gland is always absent, but in one genus Occidenthella of the family Coryphellidae , there is a clearly convergently-formed accessory gland protruding from the penial sheath (see detailed genus-level Synopsis of the family Coryphellidae genera below).