Dicharax (?) okamurai (Azuma, 1980)

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

Dicharax (?) okamurai (Azuma, 1980)

Awalycaeus okamurai Azuma, 1980: 140-141, figs 1-5.

Cipangocharax okamurai - Azuma 1982: 13, pl. 4, fig. 43; Minato 1988: 17; Minato 1993: 1, fig. 3.

Type locality.

"Mt. Sarumasa (altitude about 500-600 meters), Nitachȏ, Nitagun, Shimane Pref., Japan".

Material examined.

島根縣 1猿政山 (Shimane-ken, Sarumasayama = Shimane Prefecture, Mt. Sarumasa), coll. Sakurai, NSMT-Mo 79096 (7 shells); Japan, W-Honshu, Shimane-pref., Mt. Sarumasa-yama, ex coll. M. Azuma 1983, SMF 256326 (2 shells).

Remarks.

Protoconch low, relatively glossy, extremely finely granulated; R2 with ca. 24 low, blunt, irregular ribs, which usually overlap with the neighbouring rings nearer the tube; distance between ribs at edge of body whorl ca. half rib width; no spiral lines visible on R1.

This species has a lip that is strongly extended in the direction of the umbilicus. Also, the thickened operculum is very peculiar with a compressed hourglass shape.