Gudeodiscus (Veludiscus) emigrans emigrans ( Moellendorff , 1901)

Pall-Gergely, Barna, Hunyadi, Andras, Ablett, Jonathan, Lương, Hao Văn, Fred Naggs, & Asami, Takahiro, 2015, Systematics of the family Plectopylidae in Vietnam with additional information on Chinese taxa (Gastropoda, Pulmonata, Stylommatophora), ZooKeys 473, pp. 1-118 : 42-44

Taxon classification Animalia Stylommatophora Plectopylidae

Gudeodiscus (Veludiscus) emigrans emigrans ( Moellendorff, 1901) Figures 6E, 13 A–B

Plectopylis (Sinicola) emigrans Möllendorff 1901, Nachrichtsblatt der Deutschen Malakozoologischen Gesellschaft, 33 (5/6): 75, 76. [ “Mansongebirge”]

Gudeodiscus emigrans emigrans , - Páll-Gergely & Hunyadi 2013, Archiv für Molluskenkunde, 142 (1): 12., Figs 24, 44 a–b, 58 (map).

Material examined.

See Páll-Gergely and Hunyadi (2013).

Diagnosis.

Spiral sculpture missing or not conspicuous, parietal wall with one lamella and a short lower parietal plica anterior to the lamella.

Measurements

(in mm). D = 17.3, H = 7.5 (holotype).

Differential diagnosis.

Gudeodiscus emigrans emigrans has weaker spiral sculpture than Gudeodiscus emigrans quadrilamellatus , and has only one horizontal parietal plica anterior to the lamella (close to the lower suture), whereas Gudeodiscus emigrans quadrilamellatus has four parallel horizontal plicae. The Chinese Gudeodiscus emigrans otanii has Y-shaped palatal plicae (these are simple in the nominotypical subspecies and in Gudeodiscus emigrans quadrilamellatus ). Moreover, some specimens of Gudeodiscus emigrans otanii have two vertical lamellae (see Páll-Gergely and Asami 2014).

Intrasubspecific diversity.

Very few shells are known from museum collections. The subspecies is easily recognisable, but more material is needed to understand the intrasubspecific diversity.

Distribution.

Plectopylis (Sinicola) emigrans was described from the “Manson-Gebirge” = "Mau Son Mts, about 30 km E of Lang Son" ( Schileyko 2011) (see Figure 39).