''Theodoxus danubialis'' is a species of small

freshwater snail Freshwater snails are gastropod mollusks which live in fresh water. There are many different families. They are found throughout the world in various habitats, ranging from ephemeral pools to the largest lakes, and from small seeps and springs ...

with an operculum, an aquatic

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk in the family Neritidae, the nerites. The species is considered as endangered in Germany, Austria and in the Czech Republic.

Etymology

The Latin name ''Theodoxus danubialis'' means "God's gift to the Danube" or "The praise of God in the Danube".

Subspecies

*''Theodoxus danubialis cantianus'' (Kennard & Woodward, 1924) † *''Theodoxus danubialis danubialis'' (C. Pfeiffer, 1828) *''Theodoxus danubialis stragulatus'' (C. Pfeiffer, 1828) Biolib
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Description

Shells of ''Theodoxus danubialis'' can reach a diameter of . These shells are quite flattened, with 3-3.5 whorls. The surface has a characteristic dark brown zigzag drawing on a light background. The width of the zigzag lines is variable. The mouth is round to slightly elliptical. The operculum is pale yellow. The edge is brown and slightly thickened. The body of the snail is bright with a wide base. The antennae are long and pointed. PETER GLÖER and VLADIMIR PEŠI�
The morphological plasticity of Theodoxus fluviatilis (Linnaeus, 1758) (Mollusca: Gastropoda: Neritidae)
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Distribution

The distribution of this species is Mediterranean and

Pontic Pontic, from the Greek ''pontos'' (, ), or "sea", may refer to: The Black Sea Places * The Pontic colonies, on its northern shores * Pontus (region), a region on its southern shores * The Pontic–Caspian steppe, steppelands stretching from n ...

. It occurs in Austria, Bosnia and Herzegovina, Bulgaria, Croatia, Czech Republic (in Moravia it is critically endangered), Horsák M., Juřičková L., Beran L., Čejka T. & Dvořák L. (2010). "Komentovaný seznam měkkýšů zjištěných ve volné přírodě České a Slovenské republiky. nnotated list of mollusc species recorded outdoors in the Czech and Slovak Republics. '' Malacologica Bohemoslovaca'', Suppl. 1: 1-37
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Germany (in Bavaria only and it is critically endangered), Hungary, Italy, Romania, Slovakia, Slovenia, Ukraine, Serbia and Montenegro.WMSDB – Worldwide Mollusc Species Data Base
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Habitat

This species needs clean, oxygen-rich rivers. These snails live on hard benthic substrates, typically rocks or stony ground and feed mainly on diatoms.

Bibliography

* Peter Glöer: Die Tierwelt Deutschlands. Mollusca I Süßwassergastropoden Nord- und Mitteleuropas Bestimmungsschlüssel, Lebensweise, Verbreitung. 2. neubearb. Aufl., 327 S., ConchBooks, Hackenheim 2002 * Rosina Fechter und Gerhard Falkner: Weichtiere. 287 S., Mosaik-Verlag, München 1990 (Steinbachs Naturführer 10) * Jürgen H. Jungbluth und Dietrich von Knore: Trivialnamen der Land- und Süßwassermollusken Deutschlands (Gastropoda et Bivalvia). Mollusca, 26(1): 105-156, Dresden 2008

References

External links

* {{Taxonbar, from=Q754652 Neritidae Gastropods described in 1828