Hunyadiscus andersoni (W. Blanford, 1869)

Pall-Gergely, Barna, Muratov, Igor V. & Asami, Takahiro, 2016, The family Plectopylidae (Gastropoda, Pulmonata) in Laos with the description of two new genera and a new species, ZooKeys 592, pp. 1-26 : 6-9

Taxon classification Animalia Pulmonata Plectopylidae

Hunyadiscus andersoni (W. Blanford, 1869) Figures 3 B–C, 4 A–B, 5 C–D, 11F

Hunyadiscus andersoni 1869 Helix (Plectopylis) andersoni Blanford, Proceedings of the Zoological Society of London: 448 [Bhamo in regno Avæ et Hoetone in Yunan].

Hunyadiscus andersoni 1874 Helix andersoni , - Hanley and Theobald, Conchologia Indica …: 46, plate 112, figs 8-9 [Bhamo, and Hoetone in Yunan] (1870-1876).

Hunyadiscus andersoni 1875 Helix (Plectopylis) andersoni , - Godwin-Austen, Proceedings of the Zoological Society of London: 612, Plate 74, fig. 9.

Hunyadiscus andersoni 1885 Plectopylis Andersoni , - Möllendorff, Jahrbücher der Deutschen Malakozoologischen Gesellschaft, 12: 389 ["bei Bhamo in Oberbirma", “»Hoitone« in der chinesischen Provinz Yünnan”].

Hunyadiscus andersoni 1886 Plectopylis Andersoni , - Möllendorff, Jahrbücher der Deutschen Malakozoologischen Gesellschaft, 13: 188.

Hunyadiscus andersoni 1887 Helix andersoni , - Tryon, Manual of Conchology. 2 (3): 161, Plate 34, fig. 71; Plate 35, figs 74-75 [Bhamo, in Ava; Hoetone, In Yunan].

Hunyadiscus andersoni 1889 Helix (Plectopylis) Andersoni , - Tapparone Canefri, Annali del Museo Civico di Storia Naturale di Genova, 2a (7): 47 (=323). ["Catcin di Pun-Can, Cimfó, Monti Est di Bhamó”, “Bhamó, Hoetone"]

Hunyadiscus andersoni 1896 Plectopylis andersoni , - Gude, Science Gossip, 3: 154, figs 17 a–c [Near Bhamo and Ava, in Upper Burma and on the Yunnan-frontier].

Hunyadiscus andersoni 1899a Plectopylis (Chersaecia) andersoni , - Gude, Science Gossip, 6: 148.

Hunyadiscus andersoni 1899b Plectopylis (Chersaecia) andersoni , - Gude, Science Gossip, 6: 175.

Hunyadiscus andersoni 1914 Plectopylis (Chersaecia) andersoni , - Gude, The Fauna of British India including Ceylon and Burma. Mollusca II. ( Trochomorphidae - Janellidae ), 2: 73, 114, figs 55 a–c.

Hunyadiscus andersoni 2013 Chersaecia andersoni , - Páll-Gergely and Hunyadi, Archiv für Molluskenkunde 142 (1): 7, figs 14-15.

Types.

According to Dance (1986) the collection of Blanford is deposited in the British Museum (now: Natural History Museum, London). In the type collection of the NHM we did not find syntypes, but there is a sample (NHMUK 1906.02.02.364) which is labelled as being collected from Bhamo, one of the type localities. This sample may represent the type lot.

Museum material examined.

Yünan, Slg. Bosch, ex H. Rolle (1 juv.), SMF 172066; alte Schau-Slg/2, SMF 150117; no locality information (alte Schau-Slg.), SMF 150117/2; Upper Indwadi, NHMUK 1888.12.04.1561/2; Burma, coll. A. S. Kennard, ex Gude, NHMUK/2; Bhamo, Upper Burma, NHMUK 1906.02.02.364/5; Khakhyan Hills, Burmah, coll. Godwin-Austen, NHMUK/3; Bhamo, NHMUK/1.

Diagnosis.

A very large, discoid, angulated species with elevated, sharp callus and spirally striated protoconch.

Description.

Shell flat, angulated, light brown or corneous; ventral side of the body whorl keeled around the moderately wide, very deep umbilicus; protoconch spirally striated, radial ribs are mostly visible on its first whorl only; teleoconch equally ornamented with fine ribbing and spiral striae, resulting in rough, irregular reticulated surface on the dorsal side; ventral side also reticulated, but much weaker than the dorsal surface; 7.5-8.5 slowly increasing whorls separated by shallow suture; near the sutures the riblets sometimes supported with fine folds of the periostracum; aperture rounded, with white, slightly expanded and thickened apertural rim; callus slightly elevated, sharp, slightly S-shaped and forms two canals upon junction with the lip.

The parietal side was examined in one specimen (SMF 150117), whereas the palatal plicae is examined in specimens of the SMF and the NHM. Parietal wall with one curved horizontal lamella with occasionally an elongated upper plica, which is in con tact with the lamella; there are two small denticles on the posterior side of the lamella, these are in weak contact with the lamella; palatal side with eight horizontal plicae, first near the suture is small, the second is even smaller; the last also short and close to the lower suture and the penultimate resembles the second denticle; remaining four plicae between the first and last two are long and slim.

Measurements

(in mm). D = 24.6-27.2, H = 10.9-11.4 (n = 2, RBINS I. G. 10591, Burmah).

Differential diagnosis.

This species differs from large Chinese Gudeodiscus species (and Naggsia laomontana ) by the keeled margin of the shells. It is much larger than all Sinicola species. The largest Sinicola species, Sinicola fimbriosa (Martens, 1875) does not have a callus and has a stronger apertural margin.

Distribution.

The species is known from Northern Burma and Western Yunnan. Hoetone (Hutung Village) and Bhamo are located in Kachin Provinces, whereas Ava is in Mandalay Province (all in Burma/Myanmar). The Kakhyen Hills are situated on the Chinese (Yunnan) and Burmese (Kachin) border.