Allopeas Baker, 1935

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

Genus Allopeas Baker, 1935

Lamellaxis (Allopeas) Baker, 1935: 84. Zilch 1959: 349.

Allopeas — Schileyko 1999: 509.

Type species.

Bulimus gracilis Hutton, 1834 , by original designation.

Diagnosis.

Shell slender and conical; spire high and gradually attenuated; embryonic whorls pointed and smooth; subsequent whorls with striations. Aperture vertical, broad, and oblong; columella straight, and columellar margin expanded near umbilicus. Penis long, fusiform shape at base then narrowing towards epiphallus, and flagellum absent; vagina cylindrical and narrow tube, and ~ 1 / 2 of penis length.

Remarks.

The genus is sometimes confused with Paropeas Pilsbry, 1906 and Opeas Albers, 1850 . Allopeas can be distinguished from Paropeas by its less turreted shell, finner striations, smooth embryonic whorls, straight columella, and columellar margin expanded (Table 2 ). Paropeas possesses a mostly turreted shell, stronger irregular striations throughout and entire whorls, concave columella, and columellar margin less expanded. Additionally, Allopeas can be differentiated from Opeas by having larger and broader shell, attenuated spire, and stronger striations ( Schileyko 1999). By contrast, Opeas has a smaller and narrower shell, cylindrical or less attenuated spire, and finer striations ( Pilsbry 1906).

The genus Allopeas consists of ~ 25 species distributed across tropical regions of Asia, Europe, Africa, and America ( Schileyko 1999; MolluscaBase 2023). In Southeast Asia, Vietnam has recorded four species ( Schileyko 2011), while Cambodia, Laos, Myanmar, and Thailand have reported only one species, namely Allopeas gracile ( Gude 1914; Inkhavilay et al. 2019; Sutcharit et al. 2020 b).