Oophana obtusus (Stoliczka, 1871)

Sian Man, Nem, Siriboon, Thanit, Lin, Aung, Sutcharit, Chirasak & Panha, Somsak, 2022, Revision of the carnivorous land snail family Streptaxidae (Stylommatophora, Achatinina) in Myanmar, with description of four new species, ZooKeys 1110, pp. 39-102 : 39

Oophana obtusus (Stoliczka, 1871)

Fig. 7C, D

Streptaxis obtusus Stoliczka, 1871: 166, 167, pl. 7, figs 11-13, pl. 8, figs 1-4. Type locality: Prope Moulmein, provincia Tenasserim [Mawlamyine District, Mon State, Myanmar]. Pfeiffer 1876: 495. Nevill 1878: 3. Tryon 1885: 76, pl. 15, fig. 45. Gude 1903: 323, pl. 12, figs 8-10. Blanford and Godwin-Austin 1908: 9.

Odontartemon (Oophana) obtusus - Kobelt 1906: 106, pl. 56, figs 1-3.

Oophana obtusa - Richardson 1988: 236.

Material examined.

Moulmein: NHMUK 1903.7.1.4002 (2 shells) ex. Godwin-Austen collection. NHMUK 1871.9.23.64 (1 shell, Fig. 7D ). NHMUK 1937.7.91-92. Chauktalon, Moulmein: NHMUK 1906.2.2.342 (3 shells + 1 juvenile) ex. Blanford collection. NHMUK 1888.12.4.788-790 (3 shells, Fig. 7C ) ex. Blanford collection. Sacred Lakes, Moulmein: NHMUK 1889.3.15.1 (1 shell) ex. Godwin-Austen collection.

Description.

Shell oblique-ovate, white, translucent; whorls 6-7; spire convex with distinct suture. Shell surface glossy with fine transverse ridges, nearly smooth with few transverse ridges near peristome. Embryonic shell ~ 2½ whorls with smooth surface; following whorls regularly coiled. Shell periphery rounded; last whorl slightly axially deflected. Aperture subcircular; peristome continuous, expanded, slightly reflected, and very short sinulus. Apertural dentition with one strong parietal, one palatal, and one strong columella lamella. Umbilicus open and deep (Fig. 7C, D ).

Distribution.

This species is only known from the type locality, the southern part of Myanmar ( Stoliczka 1871).

Remarks.

No new specimens were collected in this survey; however, authenticated museum specimens were examined. Regarding genitalia, Oophana obtusus and Haploptychius burmanicus were the first two species anatomically examined and illustrated among several streptaxids in Myanmar by Stoliczka (1871), who noted that there was no noticeable difference in reproductive forms between these two species. Based on the genitalia drawing, O. obtusus has a thick penial sheath covering almost the entire penis, and vas deferens not inserted into the penial sheath, but the lengths of vagina and atrium are unclear. Thus, the description and drawing remain insufficient to confirm the distinguishing characters of this species.

Figures

Figure 7. A, B Oophana mouhoti A possible syntype NHMUK ex. Cuming collection from Camboja and B specimen CUMZ 13005 from Phra (Buddha) Cave, Tanintharyi C, D Oophana obtusus C specimen NHMUK 1888.12.4.788 - 790 from Chauktalon, Moulmein with apertural dentition and D specimen NHMUK 1871.9.23.64 from Moulmein E Oophana laevis, possible syntype NHMUK 1899.7.4.11 from Burma.