Pupilla alluvionica
| Pupilla alluvionica | ||||||||||||
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| Scientific name | ||||||||||||
| Pupilla alluvionica | ||||||||||||
| Meng & Hoffmann , 2008 |
Pupilla alluvionica is a species of snail from the family of the pupa snail , which belongs to the subordination of the land snail (Stylommatophora). It occurs in the Russian part of the Altai Mountains.
features
The right-hand wound, cylindrical and somewhat compressed case is 3.28 to 4.32 mm high and 2.16 to 2.4 mm wide. They have 5.5 to 6.5 convex turns on the periphery. The apex is rounded-flat conical . The embryonic housing consists of 1.5 turns and has a diameter of 1 to 1.1 millimeters. The apex is rounded, flat-conical. The last turn rises towards the mouth to just below the center of the periphery of the previous turn. The mouth is egg-shaped to elliptical and is oblique to the axis of the coil. The mouth is only slightly widened. The edge of the mouth is only slightly turned over and very fragile . Usually there are no teeth; a small parietal tooth is rarely observed. Shortly before the mouth there is a bulge in the neck in the form of a white, ring-shaped narrow band, which is set off from the edge of the mouth by a furrow. The rounded navel is open. The surface of the chestnut brown case is almost smooth and shows only very fine strips of growth. The shell is comparatively thin.
Similar species
The moss doll snail is much slimmer for the same size. The turns are flatter at the periphery and the callus is much more pronounced. The embryonic housing, on the other hand, is slightly smaller with a diameter of 0.85 mm. The Alpine pupa snail ( Pupilla alpicola (Charpentier, 1837)) is also slimmer, but the callus is less pronounced or absent entirely. The species also differ in their habitat requirements .
Geographical distribution and habitat
Pupilla alluvionica has so far only been found in a few localities at the foot of the Central and Eastern Altai. It occurs there from about 820 m to 2250 m above sea level.
The species occurs there preferentially below the tree line in active alluvions , which are still flooded at least during the snowmelt. The animals stay under stones in a permanently damp and wet environment. So far, they have only rarely been found at a distance from the meadows. They live there with Vallonia tenuilabris . A pioneer flora grew nearby , and not far away also Larix sibirica .
Taxonomy
The taxon was set up in 2009 by Stefan Meng and Matthias Hoffmann and named after the habitat of snails in Alluvionen. The holotype comes from the southeast Altai, Saylyugem, from open and active alluvions in the river plain (N 50 ° 01.048 '/ E 089 ° 14.177').
literature
- Stefan Meng, Matthias Hoffmann: Pupilla altaica n. Sp. and Pupilla alluvionica n. sp., two new species of Pupillidae (Gastropoda: Pulmonata: Pupilloidea) from the Russian Altay. In: Mollusca. 26 (2), pp. 229-234, Dresden 2008 PDF