Rhachistia sulphurea (Tomlin & Peile, 1930)

Sutcharit, Chirasak, Naggs, Fred & Panha, Somsak, 2010, A First Record Of The Family Cerastidae In Thailand, With A Description Of A New Species (Pulmonata: Orthurethra: Cerastidae), Raffles Bulletin of Zoology 58 (2), pp. 251-258 : 252

Rhachistia sulphurea (Tomlin & Peile, 1930)

( Fig. 1A, B )

Errorachis sulphurea Tomlin & Peile, 1930: 153–154 , Pl. 17a (type locality: Pran , Siam).

Rhachistia sulphurea — Schileyko, 1998: 169; Hemmen & Hemmen, 2001: 41

Material examined. – The figured specimen in Tomlin & Peile (1930, pl. 17) is designated herein as the lectotype NMW 1955.158 .01155 ( Fig. 1A ), and the paralectotype BMNH 1939.6 .6.17 ( Fig. 1B ) .

Remarks. – A bright creamy shell with a yellowish subsutural band clearly distinguishes this species from other known species in this region. Tomlin & Peile (1930) provided a full description of the shell and radula but the genital anatomy is unknown. Our land snail surveys in many locations throughout peninsular Thailand since 1994 have failed to find any specimens that resemble R. sulphurea . If the distribution was restricted to the type locality, Pran, Siam, then it is possible that this species is extinct. Pranburi (= Pran sensu Tomlin & Piele, 1930) lies in an area of western Thailand that has been subjected to extensive deforestation since 1930, with most trees having been felled.

Figures

Fig. 1. Shell of Rhachistia sulphurea: A, lectotype NMW 1955.158.01155; B, paralectotype BMNH 1939.6.6.17. Shell of Rhachistia conformalis Sutcharit & Panha, new species: C, holotype CUMZ 3796; D, paratype CUMZ 3797. Shell of Amimopina subangulatus: E, lectotype BMNH 1986166; F, G, specimens from Jed Sao Noi Waterfall, Saraburi (CUMZ 3798, 3799). Rhachistia conformalis Sutcharit & Panha, new species: H, at type locality (shell height about 17 mm) CUMZ 3797. Amimopina subangulatus: I, at Jed Sao Noi Waterfall, Saraburi (shell height about 15 mm) CUMZ 3650.