Murmaniidae Korshunova et al. , 2017

Family Murmaniidae Korshunova et al., 2017 View in CoL

( Figs 1, 2; Table 4)

Korshunova et al. 2017a: 2, 71, 73–8, supplementary materials.

Diagnosis: Body wide, massive. Notal edge present, continuous, reduced. Cerata non-elevated, very numerous per row. Ceratal rows branched. Rhinophores wrinkled. Special wedge-shaped structure between rhinophores. Anus cleioproctic, placed clearly toward posterior part of body, uniquely among member of the superfamily Fionoidea , or very rarely pleuroproctic. Masticatory edges of jaws commonly bear single row of simple or compound, sharpened denticles. Radula formula 0.1.0. Central teeth usually with strong cusp, not compressed by adjacent lateral denticles. Proximal receptaculum seminis. Vas deferens moderately long, prostate indistinct. Supplementary gland present, inserts into penis. Massive external permanent penial collar absent. Penis internal, broad, unarmed.

Genera included: Murmania Martynov, 2006 and? Guyvalvoria Vayssière, 1906 .

Remarks: Although it possesses a uniserial radula, the family Murmaniidae otherwise displays other unique, clearly ancestrally fuelled sets of characters for the superfamily Fionoidea ( Fig. 2), but compared to the triserial Eubranchidae , the distinctions are at the level of external morphology (see: Martynov et al. 2020). Particularly, the family Murmaniidae has a distinctly large, wide body [such massive body patterns are not very common within the suborder Aeolidacea , and can be assigned mostly to a few representatives of the superfamilies Flabellinoidea (family Paracoryphellidae , genus Chlamylla ), Aeolidioidea (family Aeolidiidae , genus Aeolidia ) and also contains only single new family Chudidae fam. nov. superfamily Chudoidea superfam. nov., see Synopsis below]. Murmaniidae have a rudimentary notal edge, a definite ancestral feature that is common within the superfamily Flabellinoidea , in turn rare in the superfamily Aeolidioidea , but within the superfamily Fionoidea , the family Murmaniidae is the only benthic family with such a character. Furthermore, the anus of Murmaniidae is distinctly cleioproctic, a character state that is rare within the predominantly acleioproctic superfamily Fionoidea . The conclusion in Kim et al. (2024) that the cleioproctic anus of Murmaniidae , and other Fionoidea families, principally differs from the cleioproctic anus of Facelinidae is erroneous. Moreover, the placement of the anus toward the posterior part of the dorsal side, and even one instance of pleuroproctic anal position ( Martynov 2006a), further highlights the uniqueness of the family Murmaniidae . At the same time, the reproductive system of Murmaniidae shows insertion of a supplementary gland into the penis, common for a majority of the families, and not into the vas deferens, as it does, for example, within the family Cuthonellidae (see Synopsis below). Taking into consideration that the insertion of a supplementary gland into the vas deferens is also so far only confirmed for the restricted, true genus Eubranchus (with types species E. tricolor ) from the family Eubranchidae , and from the drastically different family, Calmidae (see below), and both are distantly related to Murmaniidae ( Figs 1, 2), therefore, insertion of a supplementary gland into the vas deferens appears as an ancestral character for the superfamily Fionoidea .

Thus, as real evolutionary patterns commonly generate significant mosaicism in the ‘resulting’ taxa regarding ancestral and unique or other ‘novel’ characters ( Figs 1, 2; Synopsis), any lumping or putative ‘intermediate character approach’ at any level, from order to ‘species’, will fundamentally produce the wrong picture of the underlying evolutionary pathways in the level of taxonomic presentation, compared to fine-scale differentiated taxonomy (Synopsis; Figs 1, 2; Tables 1–4).