Description of a new species of the genus Cylichna (Gastropoda: Heterobranchia: Cylichnidae) from the Tatar Strait (Sea of Japan), with discussion of its taxonomical position

E.M. Chaban

Abstract. Cylichna inflata sp. nov. is described based on nine specimens collected in 1931 in the Tatar Strait (northern part of the Sea of Japan) at a depth of 69 m. The new species differs from other species of the genus in the morphology of the shell, radula, gizzard plates, and in the presence of a seminal vesicle in the copulatory apparatus. The shell proportions of C. inflata sp. nov. are similar to those of some species of the genus Cylichnoides Minichev, 1977. The emended diagnoses of Cylichna Lovén, 1846 and Cylichnoides (Eoscaphandridae) are provided.

Key words: taxonomy, morphology, shell, crop, gizzard, copulatory apparatus, North-West Pacific, Gastropoda, Heterobranchia, Cephalaspidea, Cylichna, Cylichnoides, new species

Zoosystematica Rossica, 2025, 34(1): 28–35 ▪ Published online 27 January 2025

https://doi.org/10.31610/zsr/2025.34.1.28 ▪ Open full article

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