Chersaecia mogokensis sp. nov. urn:lsid:zoobank.org:act: 8E2812E3-52AF-4CF9-A01D-FD01ED8396E7 Figs 20C, 21 E–F Diagnosis Shell large, flat, widely umbilicated, parietal wall with a single lamella and a short lower plica, palatal plicae oblique, with additional denticles at their posterior ends. Etymology The name mogokensis refers to the type locality (Mogok). This name was written on the label of the specimen, but apparently has never been published. Material examined Holotype MYANMAR: 1 shell, holotype (D = 23.6 mm), Burmah, Mogok, ruby mines, coll. Godwin-Austen (NHMUK 20140787). Description SHELL. Sinistral, almost completely flat, only protoconch protrudes above dorsal surface; original colour might be reddish-brown; protoconch consists of slightly more than 2.5 whorls, separated by shallow suture; dorsal side of the protoconch irregularly, roughly wrinkled, but ventral side (i.e., inside the umbilicus) clearly tuberculated; whole teleoconch irregularly wrinkled sometimes with spiral lines especially on the apical side; whorls 6.75; teleoconch whorls separated by a deep suture; peristome strongly thickened and slightly reflected; parietal callus strongly developed, sharp, slightly S-shaped; apertural fold very short, denticle-like, free from parietal callus. Parietal wall with a single, slightly curved lamella and a short lower plica. Palatal wall with six plicae; first and last straight, horizontal; remaining ones oblique, with additional denticles at their posterior ends. MEASUREMENTS (in mm). D = 23.6, H = 7.7 (holotype). Differential diagnosis In size and shape Chersaecia mogokensis sp. nov. resembles species of the genus Plectopylis. However, the straight, oblique palatal plicae, and the single lamella differentiates it from all species of Plectopylis. The most similar species of Chersaecia in outer shell morphology is C. shanensis, which nevertheless has strongly developed lower, main and intermediate plicae, a much stronger apertural fold, and a protoconch lacking or with a few low growth wrinkles. Chersaecia magna is also similar in outer appearance, but possesses two parietal lamellae and a very long apertural fold. All other species of Chersaecia are much smaller and/or have strongly developed main plicae. Distribution The only known specimen of Chersaecia mogokensis sp. nov. is from the type locality.

Published as part of Páll-Gergely, Barna, 2018, Systematic revision of the Plectopylinae (Gastropoda, Pulmonata, Plectopylidae), pp. 1-114 in European Journal of Taxonomy 455 on pages 44-46, DOI: 10.5852/ejt.2018.455, http://zenodo.org/record/3817707