Discus rotundatus

Discus rotundatus

''Discus rotundatus'', common name rotund disc, is a species of small, air-breathing, land snail, a terrestrial pulmonate gastropod mollusk in the family Discidae, the disk snails.
Rotund Disc Snail - Discus rotundatus Tiny land snail with a flat, densely ribbed shell with reddish brown cross bands. It was only a few mm diameter.

Habitat: Under the bark of a sycamore tree that had fallen across a river in a deciduous forest. Discus rotundatus,Geotagged,United States,Winter,disk snail,land snail,rotund disc snail,snail,terrestrial snail

Appearance

The shells of ''Discus rotundatus'' in the adult stage measure 5.7–7 millimetres in diameter and 2.4–6 millimetres in height. Shells are reddish brown with darker cross bands, flat and densely ribbed. The umbilicus is quite wide, reaching about 1/3 of the shell diameter.

Among the species of ''Discus'' in Europe and North America, ''Discus rotundatus'' is recognized by the alternating pattern of reddish brown spots, tight coiling of the whorls and broad and shallow umbilicus.

The body of this gastropod is bluish black on the upperside, while the lower side is greyish white. They mainly feed on plant debris, humus, algae and fungi.

Naming

* ''Discus rotundatus rotundatus''
⤷  ''Discus rotundatus omalisma''

Distribution

This species lives in Western and Central Europe. It is found in the Czech Republic, Poland, Ukraine and Slovakia. It is also found in Great Britain, Ireland, France, Italy, southern Scandinavia, and other countries. Its range includes Turkey.

The species has been introduced to North America where it was first found in 1937 and now is known from six Canadian provinces and 14 states, as well as the District of Columbia, in the United States. It does not appear to have the capability to become an ''invasive'' pest species in North America, as it lives in leaf litter and forms colonies where the individuals do not tend to spread widely.

Habitat

These gastropods live in forests and humid shady places, in dead wood logs, under stones, on humus and in soil litter, sometimes in colonies, at an elevation of 0–2,100 metres above sea level.
They can live both in natural habitats and in environments modified by humans, like gardens.
The species can tolerate substrate which is non-calcareous.

References:

Some text fragments are auto parsed from Wikipedia.

Taxonomy
KingdomAnimalia
DivisionMollusca
ClassGastropoda
OrderStylommatophora
FamilyDiscidae
GenusDiscus
SpeciesD. rotundatus