6 Curvella puta (Benson, 1857)

Fig. 4 D, E

Bulimus putus Benson, 1857: 330. Type locality: Tavoy [Dawei, Tanintharyi Region, Myanmar]. Pfeiffer 1859: 502. Blanford 1865: 94. Hanley and Theobald 1874: 34, pl. 80, fig. 9.

Hapalus putus — Nevill 1878: 178.

Bulimina (Hapalus) puta — Pfeiffer and Clessin 1881: 299.

Buliminus (?) putus — Kobelt 1901: 689, pl. 103, fig. 23.

Curvella puta — Pilsbry 1906: 63, 64, pl. 9, fig. 46. Gude 1914: 351, 352. Preece et al. 2022: 130, fig. 55 f.

Type specimen.

Holotype UMZC I. 102795 (Fig. 4 D; after Preece et al. 2022: fig. 55 f) ex. R. McAndrew ex. Benson collection from Tavoy, Birmah.

Other material.

NHMUK 1888.12. 4.1003–1004 (1 shell identified as C. puta; Fig. 4 E [another shell identified as C. pusilla]) ex. W. Theobald collection from Pegu. NHMUK 1906.1. 1.1033 (1 shell) ex. Godwin-Austen collection from Bassein, Pegu.

Diagnosis.

Shell conical; spire high; apex obtuse; subsequent whorls with strong and prominent growth lines. Suture impressed and whorl s slightly convex. Aperture semi-ovate and somewhat pointed above; columella straight and dilate; parietal callus thin. Umbilicus narrow.

Distribution.

This species was reported from the Tanintharyi and Bago regions of Myanmar and Thailand (Blanford 1865; Gude 1914; Panha 1998).

Remarks.

Curvella puta was described based on a single bleached specimen collected from ‘ Tavoy’ in Myanmar. No new material of this species was found during this survey, but the type specimens and authenticated museum specimens are illustrated herein.

There is a mixed-species lot, NHMUK 1888.12. 4.1003–1004, ex. the W. Theobald collection, labelled ‘ Hapalus putus Benson’ from ‘ Pegu’, consisting of two shells. The first shell (Fig. 4 E) has a high, turreted, and pointed spire, narrowly opened umbilicus, and strong radial striations, which agree with the holotype of C. puta from ‘ Tavoy’ (Fig. 4 D). The other shell (Fig. 4 C) has a lower and convex spire, fine radial striations, narrowly opened umbilicus, and without a parietal tooth, which more resembles C. pusilla . In comparison, C. pusilla possesses a closed umbilicus without a parietal tooth (Fig. 4 B), while C. plicifera has an open umbilicus and a small parietal tooth (Fig. 4 A).

This mixed-species lot suggests several interpretations: i) an extended distribution of C. puta beyond its type locality to the Bago Region in central Myanmar, and ii) the presence or absence of a parietal tooth and an open or closed umbilicus are possibly intraspecific variation rather than diagnostic characters distinguishing between C. plicifera and C. pusilla . Additional evidence and further specimens from a wider geographic range will clarify this issue.