Dendronotus zakuro Martynov, Fujiwara, Tsuchida, R. Nakano, N. Sanamyan, K. Sanamyan, Fletcher & Korshunova, 2020

Description

A medium-sized Dendronotidae, body up to 30 mm in length. Body elongate with 5-7 branched appendages on the oral veil, about 5 appendages on each rhinophoral stalk, 10-11 rhinophoral lamellae, branched lateral papillae on the rhinophoral stalk, 6-7 pairs of dorsolateral appendages, and 25-30 lip papillae. Dorsolateral appendages have an elongate primary stalk and moderately to highly branched secondary and attenuated tertiary branches. Reproductive and anal openings on the right side. General colour bright red to reddish-brownish with thin broken white lines and opaque white spots. The radular central tooth is completely smooth in adults, lacking denticles and furrows — a key diagnostic character. Vas deferens moderate in length; penis massive, long, and twisted.

Distribution

Type locality: Russia (Kamchatka, Starichkov Island, 12 m on stones; collector N. P. Sanamyan) and Japan (Hokkaido, Usujiri; Honshu, Echizen Coast of Fukui Prefecture; Sea of Japan).

Etymology

The specific epithet derives from Japanese zakuro (ザクロ, 石榴・柘榴, "pomegranate"), referring to the striking red to red-brownish coloration of the species.

Remarks

Described in the same paper as D. jamsteci and D. bathyvela — three new Dendronotus species described from Japan after a long gap. Phylogenetically clusters near a clade containing D. arcticus, D. dalli, D. kamchaticus, D. niveus, D. lacteus, D. europaeus, and D. rufus; the lowest COI interspecific distance (5.33%) is to D. europaeus.

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References

• ホクヨウウミウシ科の仲間, 中野理枝. (2004). 本州のウミウシ. ラトルズ.
• ザクロスギノハウミウシ（新称）, 小野篤司 & 加藤昌一. (2020). 新版 ウミウシ. 誠文堂新光社.