Coryphellina O'Donoghue , 1929

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 : 44

Coryphellina O'Donoghue, 1929 Figs 34, 37, 38, 39

= Nossis Bergh, 1902; non Nossis Kinberg, 1865 (senior homonym).

Type species.

Coryphellina rubrolineata O’Donoghue, 1929.

Diagnosis.

Body narrow. Notal ridge present, reduced, discontinuous, in several indistinct pieces. Cerata on low elevations, in several groups. Rhinophores similar in length or shorter than oral tentacles, densely papillated. Anterior foot corners present. Anus pleuroproctic. Distinct oral glands. Rachidian teeth with narrow compressed cusp and distinct denticles. Lateral teeth denticulated with attenuated process basally. Proximal receptaculum seminis usually bilobed. Distal receptaculum seminis present. Short prostatic, not granulated vas deferens. Penis conical to bulbous.

Species included.

Coryphellina albomarginata (Miller, 1971) comb. n. (original description in Miller 1971), Coryphellina arveloi (Ortea & Espinosa, 1998), comb. n. (original description in Ortea and Espinosa 1998), Coryphellina (?) delicata (Gosliner & Willan, 1991), comb. n. (original description in Gosliner and Willan 1991), Coryphellina exoptata (Gosliner & Willan, 1991), comb. n. (Fig. 37) (original description in Gosliner and Willan 1991), Coryphellina (?) hamanni (Gosliner, 1994), comb. n. (original description in Gosliner 1994), Coryphellina indica (Bergh, 1902) comb. n. (original description in Bergh 1902), Coryphellina lotos sp. n. (Fig. 38), Coryphellina marcusorum (Gosliner & Kuzirian, 1990), comb. n. (original description in Gosliner and Kuzirian 1990), Coryphellina (?) poenicia (Burn, 1957), comb. n. (original description in Burn 1957), Coryphellina rubrolineata O’Donoghue, 1929 (Fig. 39) (original description in O’Donoghue 1929), Coryphellina (?) westralis (Burn, 1964), comb. n. (original description in Burn 1964).

Remarks.

The genus Coryphellina is well delineated from all Flabellinidae s. str. taxa. Morphologically most of Coryphellina species are characterised by papillated rhinophores and a peculiar bilobed receptaculum seminis. Externally Coryphellina has a discontinuous but still distinct notal edge which forms only slightly raised ceratal elevations (compared to the compound stalks in the true Flabellina and Calmella ). These morphological characteristics are consistent with the molecular phylogenetic analysis where all Coryphellina place in a compact clade (Fig. 2). However, the type species Coryphellina rubrolineata forms a separate subclade within other Coryphellina . This may be consistent with previous information ( Gosliner and Willan 1991) that C. rubrolineata has a “triaulic” reproductive system, which is unusual for most aeolidaceans. Since the fine precise relation between postampullar ducts and ducts of seminal reservoirs has not been studied in detail in the majority of traditional Flabellinidae and also because putative triauly in C. rubrolineata is different from well-defined “typical” triauly of dorid nudibranchs, we consider all flabellinids with papillated rhinophores and a bilobed receptaculum seminis as belonging to the same genus Coryphellina .

The genus Nossis Bergh, 1902 was established for a type species of N. indica from the Gulf of Siam ( Bergh 1902). When he established the genus Coryphellina O’Donoghue (1929) did not mention the previously described genus Nossis but later a close relationship between Nossis and Coryphellina was noticed (e.g., Nordsieck 1972; McDonald 2009) and the type species of the genus Coryphellina has been treated under the name Nossis rubrolineata . However, the genus name Nossis Bergh, 1902 for nudibranchs was preoccupied by the name Nossis Kinberg, 1865 which was established for a polychaete ( Kinberg 1865). Therefore these two names are homonyms, and the junior one should therefore be replaced with the available name Coryphellina O’Donoghue, 1929. In the present study we have investigated two syntypes of Nossis indica Bergh, 1902 (NHMD GAS-2008) and confirm that their external characters are concordant with the genus Coryphellina . We also find in both syntypes of Nossis indica densely papillated rhinophores essentially similar to those in the genus Coryphellina , contrary to the description of rhinophores of N. indica in the first description of Bergh (1902: 211) as bearing “leaves” that instead imply a perfoliate condition ( Burn 1964). Perhaps, Bergh recognized the rhinophoral papillae but just described it as “leaves”. In addition, Burn (1964) also described another species of Nossis , N. westralis , and mentioned the genera Nossis and Coryphellina , but did not synonymise them; instead he highlighted their differences most likely because of the description of N. indica in Bergh (1902) regarding the rhinophoral leaves (instead of rhinophoral papillae). Accordingly, the species Nossis indica is transferred here to the genus Coryphellina , but its exact relationship to other common Indo-West Pacific Coryphellina such as C. rubrolineata and C. exoptata remains to be investigated. We are not excluding the possibility that C. indica is the same or a closely related species to the type species of Coryphellina , C. rubrolineata . We also tentatively assign Nossis westralis as a species of the genus Coryphellina but it needs to be further studied. The proposed family Nossidae Odhner, 1968 thus is a junior synonym of Flabellinidae s. str. Odhner ( Odhner 1968) also proposed a few more genera within the family " Nossidae "; no descriptions were provided for these genera and they are nomina nuda according to article 13. 1 ( ICZN 1999).