Dioryx compactus (Bavay & Dautzenberg, 1900)

Pall-Gergely, Barna, Sajan, Sheikh, Tripathy, Basudev, Meng, Kaibaryer, Asami, Takahiro & Ablett, Jonathan D., 2020, Genus-level revision of the Alycaeidae (Gastropoda, Cyclophoroidea), with an annotated species catalogue, ZooKeys 981, pp. 1-220 : 1

Dioryx compactus (Bavay & Dautzenberg, 1900)

Alycaeus (Dioryx) compactus Bavay & Dautzenberg, 1900a: 119-120.

Alycaeus (Dioryx) compactus - Bavay and Dautzenberg 1900b: 454, pl. 11, figs 9, 10.

Dioryx compactus - Kobelt 1902: 337-338; Varga 1972: 136, figs 15, 16; Páll-Gergely et al. 2017: 10, fig. 4C.

Type locality.

“Bac-Kan”.

Material examined.

Tonkin, Bac-Kan, leg. Messager, MNHN-IM-2000-31796 (1 syntype).

Remarks.

Five shells in the Senckenberg Museum (Tonkin, Bac-Kan, Cho-Ra, leg. Messager, coll. Rolle ex coll. Bosch, SMF 192287) were labelled as syntypes, although they clearly belong to a different species than the single syntype in MNHN Paris, which agrees with the figures in Bavay and Dautzenberg (1900b). This single shell is identical to Dioryx distortus , but smaller. A comprehensive revision would probably reveal that the two names are synonyms.

The following remarks are based on the syntype from Paris: protoconch matte; R1 with irregular, very weak, widely spaced ribs and dense spiral striae of the same strength, although due to small space between spiral striae, they are much more conspicuous than the rare radial lines; R2 long, with very thin lighter and darker thicker stripes, the overall surface is smooth, glossy.