Curvella scrobiculata ( Blanford, 1865 )

Man, Nem Sian, Ablett, Jonathan D., Lwin, Ngwe, Sutcharit, Chirasak & Panha, Somsak, 2024, Contributions on a small collection of the former Subulinidae Fischer & Crosse, 1877 (Eupulmonata, Achatinoidea) with catalogue of the Glessula and Rishetia species recorded from Myanmar, ZooKeys 1208, pp. 173-239 : 173-239

7 Curvella scrobiculata ( Blanford, 1865)

Fig. 4 F

Bulimus scrobiculatus Blanford, 1865: 77. Type locality: Pegu, west of Irawady [Bago Region, west of Ayeyarwady River, Myanmar]. Pfeiffer 1868: 151. Hanley and Theobald 1874: 34, pl. 79, fig. 9.

Bulimina (Hapalus) scrobiculata — Pfeiffer and Clessin 1881: 300.

Hapalus scrobiculatus — Nevill 1878: 175.

Curvella scrobiculata — Pilsbry 1906: 64, 65, pl. 9, fig. 49.

Curvella scrobiculatus — Gude 1914: 350, 351.

Type specimens.

Possible syntypes NHMUK 1906.2. 2.226 (2 shells; Fig. 4 F ) ex. Blanford collection from Akouktong, Pegu.

Diagnosis.

Shell conical; spire high; apex obtuse; subsequent whorls with strong and equally spaced radial ridges throughout. Suture impressed and whorls flattened convex. Aperture truncate and somewhat pointed posteriorly; columella straight and thickened; parietal callus thin. Umbilicus narrowly open.

Distribution.

This species is known only from the type locality and is probably an endemic species in Myanmar.

Remarks.

No new material of this species was found in this study, and the probably syntype is illustrated here for the first time. Blanford (1865) described three Curvella species, C. plicifera , C. pusilla , and C. scrobiculata , from Myanmar consecutively in the same publication with their type localities as ‘ Pegu’ [now in the Bago Region]. Compared to the authenticated museum specimens, C. scrobiculata is distinct from C. puta by having strong radial ribs, flatter whorls, and a more turreted, pointed, and higher spire. Furthermore, C. scrobiculata is easily distinguishable from C. plicifera and C. pusilla by its higher, pointed, turreted spire and prominent radial ribs. In contrast, the two latter species exhibit a lower and more convex spire with finer radial striations to nearly smooth shell surfaces. These are considered possible syntype material since the locality data (Akouktong, Pegu) does not exactly match that which was given in the original description (Pegu, west of Irawady).

Figures

Figure 4. A Curvella plicifera, possible syntype NHMUK 1906.2. 2.235 from Thyetmyo, Pegu; Akouktoung B, C Curvella pusilla B possible syntype NHMUK 1906.2. 2.234 from Akouktong, Pegu and C specimen NHMUK 1888.12. 4.1003–1004 from Pegu D, E Curvella puta D holotype UMZC I. 102795 from Tavoy, Birmah (after Preece et al. 2022: fig. 55 f) and E specimen NHMUK 1888.12. 4.1003–1004 from Pegu F Curvella scrobiculata, possible syntype NHMUK 1906.2. 2.226 from Akouktong, Pegu.