Pupilla loessica is a species of minute air-breathing land snail, a terrestrial pulmonate gastropod mollusk or micromollusk in the family Pupillidae.
Pupilla loessica is a significant glacial index species for the Pleistocene in Central and Eastern Europe and also in parts of NorthWestern Europe.[1] It lives as extant species in Central Asia.[1]
Pupilla loessica was first described by Czech biologist Vojen Ložek in 1954 from late Pleistocene loess from Předmostí u Přerova (Moravia, Czech Republic).[1] For the Pleistocene in Central and Eastern Europe and also in parts of NorthWestern Europe, Pupilla loessica constitutes a significant glacial index species.[1]
Individual specimens had been found since the early Pleistocene.[1] It was widespread above all in the middle Pleistocene and late Pleistocene.[1]
Fossil distribution of Pupilla loessica include:
At an early date (1986), Ložek supported the view that Pupilla loessica was alive at the present time in Central Asia.[1]
Recent distribution of Pupilla loessica include:
The shells of Pupilla loessica are about 3 mm high, thin, cylindrical-ovate and have a rounded conical apex.[1] The approximately 5 strongly curved whorls gradually increase in height and are finely and irregularly ribbed.[1] The short elliptical aperture has no denticles, no palatal callus and is only slightly broadened.[1] The crest is at most indicated by a weak band.[1]
The shells are usually a strong brown colour when fresh.[1] The fine ribs evidence very low, fragile rims which are not always visible in recent shells.[1] On weathered shells the fine ribs are still visible although less pronounced, as on the shells of the Pleistocene Pupilla loessica.[1]
The width of the recent shells is 1.6-1.8 mm.[1] The height of the shells of the recent shell is 2.5-3.3 mm.[1]
The species differs from Pupilla muscorum by its smaller size, the strongly rounded and ribbed whorls and the lack of denticles and crest.[1] The species is similar to Pupilla alpicola with similar intraspecific shell shape differences across time suggesting that similar niche shifts have led to similar transformations in parallel.[4]
Pupilla loessica occur from woodland to dry steppe.[3] The altitude ranges from 560 m a.s.l. to high altitude habitats around 3000 m a.s.l.[1] This species prefer continental types of habitat with average annual temperatures markedly below 0 °C.[1] The climate ranges from continental to sub-boreal climate.[1] Although it is a frequent loess mollusc, it apparently lived in various glacial habitats.[1]
Pupilla loessica is found in various different habitats in the Saylyugem Mountains.[1] These habitats range from stony steppe via open woodland with Larix sibirica, shrubland, mesophilic meadows to humid high altitude meadows with Carex sp. and Dryas oxyodonta (alpine tundra).[1]
For example in Saylyugem Mountains Pupilla loessica lives in 2200–2650 m a.s.l.[1] The closest known meteorological station is the Kosh Agach Station: the average annual temperature recorded amounts to –6.7 °C (January –32 °C, July 13 °C) and the annual rainfall amounts to about 110–150 mm on average.[1]
This species often accompanies the so-called Pupilla fauna and Columella fauna (according to Ložek 1964).[5][1] In addition to Pupilla spp., species which like humidity, such as Columella columella or Vertigo genesii, are also often found together with Pupilla loessica.[1] The corresponding accompanying fauna is also adapted to the cold habitats, including e.g. Columella columella, Vertigo genesii, Vallonia tenuilabris, etc.[1] Such malacofauna in recent habitats (especially on the humid alpine meadows) correspond to those of the Pleistocene glacial habitats of the Central European region.[1]
This article incorporates CC-BY-3.0 text from the reference[1]
Pupilla loessica is a species of minute air-breathing land snail, a terrestrial pulmonate gastropod mollusk or micromollusk in the family Pupillidae.
Pupilla loessica is a significant glacial index species for the Pleistocene in Central and Eastern Europe and also in parts of NorthWestern Europe. It lives as extant species in Central Asia.
