Dicharax (?) birugosus (Godwin-Austen, 1893)

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 (?) birugosus (Godwin-Austen, 1893) Fig. 19

Alycaeus bi-rugosus Godwin-Austen, 1893: 593.

Alycaeus bi-rugosus - Godwin-Austen 1897: 387, pl. 63, figs 5, 5a.

Alycaeus (Dicharax) birugosus - Kobelt 1902: 366.

Alycaeus birugosus - Godwin-Austen 1914: 370; Godwin-Austen 1914: 387.

Alycaeus canaliculus Godwin-Austen, 1914: 371, pl. 154, fig. 11. syn. nov.

Alycaeus birugosus var. - Godwin-Austen 1914: 370, pl. 154, figs 7, 7a.

Alycaeus birugosus var. minor Godwin-Austen, 1914: 370, pl. 155, figs 9, 9a.

Alycaeus (Chamalycaeus) canaliculus - Gude 1921: 225.

Alycaeus (Dicharax) birugosus - Gude 1921: 239-240.

Alycaeus (Dicharax) birugosus var. minor - Gude 1921: 240.

Chamalycaeus (Chamalycaeus) canaliculus - Ramakrishna et al. 2010: 53.

Chamalycaeus (Dicharax) birugosus - Ramakrishna et al. 2010: 57.

Type locality.

"Khasi Hills and Manipur" ( A. birugosus ); "Garo Hills" ( A. birugosus var. minor ); "Teria Ghat, foot of the Khasi Hills" ( A. canaliculus ).

Material examined.

Khasi Hills, leg. Godwin-Austen, NHMUK 1903.7.1.2628 (2 syntypes of A. birugosus , Fig. 19B ); Jawai, Jiantia Hills, 282a, leg. Godwin-Austen, NHMUK 1903.7.1.2571 (7 shells, labelled as " birugosus var."); Garo Hills, NHMUK 1903.7.1.2755 (1 syntype of Alycaeus birugosus var. minor , labelled as duorugosus var. minor ); Teria Ghat, Khasi, leg. Godwin-Austen, NHMUK 1903.7.1.2764 (1 syntype of A. canaliculus , Fig. 19A ).

Remarks.

Alycaeus birugosus and A. canaliculus are practically identical and both of them inhabit the Khasi Hills. Thus, the latter is moved to the synonymy of the former.

Protoconch low, rather glossy, without spiral lines; R1 without spiral lines; R2 short, with blunt, straight ribs. Specimens labelled as " birugosus var." are smooth on R1, whereas typical shells are more strongly sculptured.

Comments relating to "var. minor ": protoconch low, rather glossy, without spiral lines; R1 glossy, without spiral lines; R2 short, with regular, blunt, not bent ribs.

Figures

Figure 19. Shells of Dicharax (?) birugosus (Godwin-Austen, 1893) A Alycaeus canaliculus Godwin-Austen, 1914, (NHMUK 1903.7.1.2764) B A. birugosus Godwin-Austen, 1893, syntype (NHMUK 1903.7.1.2628). Photographs: Kevin Webb (NHM).