Ptychopatula orcella (Stoliczka, 1873) Figure 45B

Pupa Pupa ( Pupisoma) Pupisoma orcella Stoliczka, 1873: 33, pl. 2, fig. 2.

Type locality.

"Penang island".

Material examined.

Gunung Doya: ME 8925.

Distribution in Borneo.

Sarawak: Kuching Division. Sabah: Tawau Division. Distribution elsewhere. Malay Peninsula, Indo-Australian archipelago (Vermeulen and Whitten 1998).

Remarks.

Only dry shells were found during the surveys. It differs from Ptychopatula circumlitum (Hedley, 1897) and P. dioscoricola (C. B. Adams, 1845) by having irregularly spaced ribs on shell surfaces (visible at 40 × magnification). This is probably the first record of sinistral form for species in the Genus Ptychopatula . For further details, see Pilsbry (1920-1921: 29).