Dendronotus kalikal Ekimova, Korshunova, Shepetov, Neretina, Sanamyan & Martynov, 2015

Korshunova, Tatiana, Bakken, Torkild, GrØtan, Viktor V., Johnson, Kjetil B., Lundin, Kennet & Martynov, Alexander, 2021, A synoptic review of the family Dendronotidae (Mollusca: Nudibranchia): a multilevel organismal diversity approach, Contributions to Zoology 90 (1), pp. 93-153 : 122-123

Dendronotus kalikal Ekimova, Korshunova, Shepetov, Neretina, Sanamyan & Martynov, 2015

Fig. 7

Dendronotus kalikal Ekimova, Korshunova, Shepetov, Neretina, Sanamyan & Martynov, 2015: 872–874 , 6F, 8E, 16C, 18B, 19; Korshunova et al., 2019b: 8–9, Figs 1 , 3M–Q .

Extended diagnosis. Body narrow. Four to five pairs of branched dorsolateral appendages (plus 2–3 posterior smaller processes). Four to five oral veil appendages. Five appendages (apparently similar in size) of rhinophoral stalks. Lateral papilla of rhinophoral sheaths present. Rhinophoreswith 8–14 lamellae. Four to six lip papillae. Basal colour brownish, with creamy to whitish areas, dorsum, dorsolateral appendages, and upper sides of foot bear brownishorangelinesand dots, partlyarranged in blurred subparallel pattern. Dorsal processes of jaws inclined posteriorly at approximately 35–40° to the longitudinal axis of the jaw body and 0.45 of its length. Masticatory processes bear denticles (possibly including ridge-like structures). Radula with up to 31 rows of teeth. Central tooth with deep furrows and with up to 18 distinct denticles. Up to eight lateral teeth withup to eight denticles. Ampulla moderately voluminous, folded. Bursa copulatrix large, considerably elongate, narrowly-oval. Seminal receptaculum small placed distally at a short distance from the vaginal opening. Prostate discoid with circa 20 alveolar glands. The vas deferens is moderate in length, penis relatively long, slightly curved. Body length up to 15 mm (preserved).

Distribution. NW Pacific from Kamchatka to northern Kurile Island and Bering Strait, Russia.

Bathymetry. 14–60 mdepth.

Remarks. Although this specieswas previously confused with D. frondosus , D. kalikal is very distinct from it by morphological features (mottled body, brownish colouration with indistinct but commonly present dorsal blurred subparallel stripes), radular patterns and molecular phylogenetic data. In the present study we provide evidence that in the North Atlantic to the Kara Sea there is a sister species, D. yrjargul sp. nov., separate from D. kalikal , see above.

Figures

FIGURE 1 Phylogenetic relationships of the species of the genus Dendronotus based on COI + 16S + 28S + H3 concatenated dataset inferred by Bayesian Inference (BI). Numbers represent posterior probabilities from BI and bootstrap values for Maximum Likelihood.Some branches are collapsed at species level.Dendronotus elegans from the type region (North Atlantic) are highlighted in dark purple. Abbreviations:h – holotype; p – paratype.Summary of species delimitation results from ABGD analyses for the COI dataset is shown

FIGURE 3 A.Map of the Northern Hemisphere showing the distribution of D.elegans (including “D.niveus”), D.kalikal, and D.yrjargul sp. nov.The type locality of D.elegans is indicated by crossed lines. B. The haplotype networks based on cytochrome c oxidase subunit I (COI), 16S rRNA (16S), and 28S rRNA (28S) molecular data showing genetic mutations occurring within D.elegans (“D.niveus”), D. kalikal, and D.yrjargul sp. nov. specimens.Abbreviations:BeSt – Bering Strait; BS – Barents Sea; Gr – Greenland; Km – Kamchatka; KS – Kara Sea; Ku – Kuril Islands; LS – Laptev Sea; Nf – Newfoundland; NS – Norwegian Sea; WS – White Sea.Type locality of D.elegans is marked on the map by “x”.

FIGURE 7 Representaives of the genus Dendronotus (living specimens). PHOTOGRAPHS BY T. KORSHUNOVA, A. MARTYNOV, K. FLETCHER, D. MILLER, Y. FUJIWARA, K. HASEGAWA, K. SANAMYAN, N. SANAMYAN, AND O. ZIMINA