Pupilla loessica is a species of small air-breathing land snail, a terrestrial pulmonate gastropod mollusk or micromollusk in the family Pupillidae.

[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 fine ribs evidence very low, fragile rims which are not always visible in recent shells.

[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] This species prefer continental types of habitat with average annual temperatures markedly below 0 °C.

[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.