Pyramidula przevalskii

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Pyramidula przevalskii
Pyramidula przevalskii

Pyramidula przevalskii

Systematics
Order : Lung snails (pulmonata)
Subordination : Land snails (Stylommatophora)
Superfamily : Pupilloidea
Family : Pyramid snails (Pyramidulidae)
Genre : Pyramidula
Type : Pyramidula przevalskii
Scientific name
Pyramidula przevalskii
Lindholm , 1922

Pyramidula przevalskii is a species of snail in the family of pyramid snails (Pyramidulidae) from the suborder of land snails (Stylommatophora).

features

The right-hand winding case is low-conical, measuring up to 2.8 to 3 mm in height and 3 to 3.25 mm in width. This means that the case is slightly wider than it is high (H / B index around 0.9). The 4½ slowly increasing turns are only slightly convex at the periphery. They are separated from each other by a deep seam. The last turn develops a clear edge on the periphery and is relatively wider. The umbilicus is open, the navel gap takes up about 0.25 to 0.2 of the width of the case. The cross-elliptical to slightly moon-shaped mouth is relatively large. It is inclined to the coil axis. The edge of the mouth is simple and straight and is only turned over in the area of ​​the navel.

The thin-walled housing is red-brown to horn-colored. The Teleoconch has fine to coarser strips of growth at irregular intervals.

Similar species

Pyramidula przevalskii has a comparatively very large housing in the adult stage. In addition, the navel gap is comparatively very narrow, the other species of the genus Pyramidula all have a larger navel gap in relation to the housing width.

Geographical distribution and habitat

The distribution area is limited to a small area in western China ( Xinjiang , Uighur Autonomous Region, Hotan , Yutian and Keriya counties ). The type material comes from an altitude of 10,400 ft. Above sea level (approx. 3,170 m above sea level).

Taxonomy

The taxon was identified in 1922 by Wassili Adolfowitsch Lindholm as Pyramidula (Pyramidula) rupestris subsp. przevalskii introduced into the scientific literature. Henry Augustus Pilsbry followed Lindholm by continuing to regard the taxon as a subspecies of Pyramidula rupestris .

literature

  • Igor Balashov, Nina Gural-Sverlova: Terrestrial molluscs of the genus Pyramidula (Pyramidulidae, Pulmonata, Gastropoda) in the East Europe, Central Asia and adjacent territories. Zoologicheskiĭ zhurnal, 90 (12): 1423–1430, Moscow 2011 ResearchGate

Individual evidence

  1. Wassili Adolfowitsch Lindholm: On a new form of Pyramidula rupestris Drap. (Gastropoda Pulmonata) from Western China. Annuaire du Musée Zoologique / Ежегодник Зоологического музея, 23: 255–256, Petrograd / Leningrad / St. Petersburg 1922
  2. ^ Henry Augustus Pilsbry: Manual of conchology, vol. 28: geographic distribution of Pupillidae; Strobilopsidae; Valloniidae and Pleurodiscidae. 226 pp., Conchological departament, Academy of natural sciences of Philadelphia, Philadelphia 1935 Online at Biodiversity Heritage Library , pp. 186/87.

annotation

  1. ↑ However, it is not the largest case in the genus Pyramidula as Balashov and Gural-Sverlova claim that the var. Scotaea Bourguignat, 1864 from Algeria, is a little larger with 3 x 3.5 mm.