Dicharax (?) crispatus (Godwin-Austen, 1871)

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 (?) crispatus (Godwin-Austen, 1871)

Alycaeus crispatus Godwin-Austen, 1871: 91-92, pl. 4, fig. 1.

Alycaeus crispatus - Godwin-Austen 1875: 8, pl. 4, fig. 3.

Alycaeus (Dicharax) crispatus - Kobelt 1902: 367; Gude 1921: 242-243.

Alycaeus crispatus - Godwin-Austen 1914: 371-372, pl. 145, figs 1, 1a, 1b; Godwin-Austen 1914: 389.

Chamalycaeus (Dicharax) crispatus - Ramakrishna et al. 2010: 58; Tripathy et al. 2018: 789.

Type locality.

"Khasia, Jiantia and N. Cachar Hills".

Material examined.

Shibak, Habiang Garo Hills, NHMUK 1903.7.1.2635 (5 syntypes); Same container (probably same locality), NHMUK 1903.7.1.2759 (11 syntypes).

Godwin-Austen (1914: 372) explained that the Alycaeus crispatus variety from north Cachar in his previous paper ( Godwin-Austen 1871: 93) was renamed A. asaluensis . The originally figured sample ( Godwin-Austen 1871: pl. 4, fig. 1) is from Shibak, Gabir valley (Godwin-Austen, 1914: 372).

Remarks.

Protoconch moderately elevated, matte, no spiral lines visible; R1 rather regularly ribbed, also without spiral lines; R2 relatively short, with regular, widely spaced, sharp ribs.

The placement of the species in the genus Dicharax is based on the absence of spiral striation on the entire shell; however, the sharp R2 ribs are characteristic of the genus Chamalycaeus . The shape of protoconch shows some variation within species. Namely, typical crispatus and typical cristatus minimus shells have only slightly elevated protoconchs, whereas it is characteristically Chamalycaeus -like (strongly elevated) in D. crispatus makarsae specimens.