Endothyrella sowerbyi (Gude, 1899)

Pall-Gergely, Barna, Budha, Prem B., Naggs, Fred, Backeljau, Thierry & Asami, Takahiro, 2015, Review of the genus Endothyrella Zilch, 1960 with description of five new species (Gastropoda, Pulmonata, Plectopylidae), ZooKeys 529, pp. 1-70 : 41-42

Taxon classification Animalia Pulmonata Plectopylidae

Endothyrella sowerbyi (Gude, 1899) Figure 13 C–D

Endothyrella sowerbyi 1899a Plectopylis sowerbyi Gude: Science Gossip, 5: 239, figs 93 a–f. ["Khasi Hills: Assam"].

Endothyrella sowerbyi 1899c Plectopylis (Endothyra) sowerbyi , - Gude: Science Gossip, 6: 148, 149.

Endothyrella sowerbyi 1899d Plectopylis (Endothyra) sowerbyi , - Gude: Science Gossip, 6: 175, 177.

Endothyrella sowerbyi 1914b Plectopylis (Endothyra) sowerbyi , - Gude: The Fauna of British India …: 72, 80-81, figs 30 a–f.

Endothyrella sowerbyi 1915 Plectopylis (Endothyra) sowerbyi , - Gude: Records of the Indian Museum, 8: 507, 509.

Types.

Khasia Hills, India, NHMUK 1922.8.29.48. (holotype, Figure 13C).

Additional material examined.

Indien, leg. Stoliczka, coll. Oberwimmer, NHMW 109252/2 (mixed sample with Endothyrella plectostoma : NHMW 71640/O/415); Ostindien, Pegu, leg. Stoliczka, coll. Edlauer, 477, NHMW 109253/7 (mixed sample with Endothyrella plectostoma : NHMW 75000/E/4770); Darjeeling, Himalaya, India, coll. Rušnov ex coll. Blume, NHMW 71770/R/15 (3 shells; mixed sample with Endothyrella plectostoma : NHMW 71770/R/14); Khasi Hills, leg. Stoliczka, 1880, NHMW 109254 (approx. 70 shells; mixed sample with Endothyrella plectostoma : NHMW 92593 and Endothyrella blanda : NHMW 109255); Khasi Hills, coll. W. Blanford, NHMUK 1906.2.2.356.4 (3 shells; mixed sample with Endothyrella plectostoma : NHMUK 1906.2.2.356.1-3); Darjeeling, 3500', leg. Lister, NHMUK 1907.9.13.11-22/11; Birma, Moulmein, Hinterindien, coll. Krüper 1928, ex coll. Oberwimmer, SMF 346406/2 (mixed sample with Endothyrella plectostoma : SMF 118090); Khasi Hills, coll. Bosch, ex coll. Rolle, SMF 346408/5 (mixed sample with Endothyrella plectostoma : SMF 172072) (Fig. 13D); Khasi Hills, coll. Jetschin, ex coll. Linter 1893, SMF 118087/1; Darjeeling, Himalaya, coll. Jetschin ex coll. Oberwimmer 1899, SMF 346407/2 (mixed sample with Endothyrella plectostoma : SMF 118088).

Diagnosis.

A very small, sinistral species with narrow umbilicus (but wider than in the three similar species; affinis , plectostoma , tricarinata ), rather domed dorsal surface, and hairs standing in five rows on the body whorl; the hairs are usually missing and the ventral side is with relatively strong radial lines; plication similar to Endothyrella plectostoma , but the main anterior parietal plica is missing or weak.

Measurements

(in mm): D: 7.8-8.6, H: 4.3-5.0 (n = 3, SMF 346408).

Differential diagnosis.

Endothyrella affinis is larger, has lighter shell with narrower umbilicus and a weaker sculpture. Endothyrella sowerbyi has a wider umbilicus and a thinner peristome than Endothyrella plectostoma . Moreover, the spire is lower and the dorsal side is rather domed in Endothyrella sowerbyi (conical in plectostoma ), and the main parietal plica is weaker or missing. See also under Endothyrella tricarinata and Table 5.

Distribution.

Museum specimens are collected from the Khasi Hills, Darjeeling, and Burma.

Remarks.

During the preparation of this revision, Endothyrella sowerbyi was handled as the synonym of Endothyrella plectostoma , because the only known specimen (the holo type) looked like a juvenile shell of Endothyrella plectostoma . The first author recognized that Endothyrella sowerbyi is a valid species in the Senckenberg Museum in August, 2015, because of several mixed samples deposited there. Thus, the Endothyrella plectostoma / sowerbyi sample of the SMF were identified and the Endothyrella sowerbyi shells were separated by B. Páll-Gergely. The Endothyrella plectostoma samples in the NHM were checked by Jonathan Ablett, whereas those in the NHMW were examined by Zoltán Fehér.