Curvella pusilla ( 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

5 Curvella pusilla ( Blanford, 1865)

Fig. 4 B, C

Spiraxis pusilla Blanford, 1865: 78. Type locality: Prome district, Pegu [Pyay District, Bago Region, Myanmar]. Pfeiffer 1868: 192. Hanley and Theobald 1874: 34, pl. 79, fig. 8.

Hapalus pusillus — Nevill 1878: 174.

Stenogyra [Spraxis (Euspiraxis)] pusilla — Pfeiffer and Clessin 1881: 324.

Curvella pusilla — Pilsbry 1906: 64, pl. 9, fig. 48. Gude 1914: 351.

Type specimens.

Possible syntypes NHMUK 1906.2. 2.234 (2 shells; Fig. 4 B ) ex. Blanford collection from Akouktong, Pegu.

Other material.

NHMUK 1888.12. 4.1003–1004 (1 shell identified as C. pusilla ; Fig. 4 C [another shell identified as C. puta ]) ex. W. Theobald collection from Pegu.

Diagnosis.

Shell ovate conic; spire low; apex bluntly obtuse; subsequent whorls with prominent growth lines. Suture shallow and whorls slightly flattened. Aperture broadly ovate and pointed posteriorly; columella twisted and expanded; parietal callus thin. Umbilicus closed.

Distribution.

This species seems restricted to Myanmar and is known only from the type locality. The modern administrations of the type locality are ‘ Prome district’ [Pyay District] and ‘ Pegu’ [Bago Region].

Remarks.

No new material of this species was found in this study, and only the probable syntypes were examined. These are considered possible syntype material since the locality data (Akouktong, Pegu) does not precisely match that which was given in the original description (Prome district, Pegu).

Blanford (1865) noted that C. pusilla resembles the young specimen of C. puta ( Benson, 1857) , but this species has a closed umbilicus, while C. puta possesses an opened umbilicus. We recognise C. pusilla as a valid species following Blanford’s description, and no new materials of this species were examined in this study.

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.