''Theodoxus danubialis'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of small freshwater snail with an operculum, an aquatic gastropod

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

in the family

Neritidae Neritidae, common name the nerites, is a taxonomic family of small to medium-sized saltwater and freshwater snails which have a gill and a distinctive operculum. MolluscaBase eds. (2021). MolluscaBase. Neritininae Poey, 1852. Accessed through: ...

, the nerites. The species is considered as endangered in

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

Austria Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...

and in the

Czech Republic The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. The ...

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 The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western Europe, Western and Southern Europe and Anatolia, on the south by North Africa ...

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 no ...

. It occurs in

Bosnia and Herzegovina Bosnia and Herzegovina ( sh, / , ), abbreviated BiH () or B&H, sometimes called Bosnia–Herzegovina and often known informally as Bosnia, is a country at the crossroads of south and southeast Europe, located in the Balkans. Bosnia and H ...

Bulgaria Bulgaria (; bg, България, Bǎlgariya), officially the Republic of Bulgaria,, ) is a country in Southeast Europe. It is situated on the eastern flank of the Balkans, and is bordered by Romania to the north, Serbia and North Macedo ...

Croatia , image_flag = Flag of Croatia.svg , image_coat = Coat of arms of Croatia.svg , anthem = "Lijepa naša domovino"("Our Beautiful Homeland") , image_map = , map_caption = , capit ...

(in

Moravia Moravia ( , also , ; cs, Morava ; german: link=yes, Mähren ; pl, Morawy ; szl, Morawa; la, Moravia) is a historical region in the east of the Czech Republic and one of three historical Czech lands, with Bohemia and Czech Silesia. The m ...

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 ''Malacologica Bohemoslovaca'' is a peer-reviewed open access scientific journal covering all aspects of malacology. It was published by the Slovak Academy of Sciences since 2005. It is published by the Department of Botany and Zoology, Faculty of ...

'', Suppl. 1: 1-37
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(in

Bavaria Bavaria ( ; ), officially the Free State of Bavaria (german: Freistaat Bayern, link=no ), is a state in the south-east of Germany. With an area of , Bavaria is the largest German state by land area, comprising roughly a fifth of the total lan ...

only and it is critically endangered),

Hungary Hungary ( hu, Magyarország ) is a landlocked country in Central Europe. Spanning of the Pannonian Basin, Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the ...

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...

Romania Romania ( ; ro, România ) is a country located at the crossroads of Central, Eastern, and Southeastern Europe. It borders Bulgaria to the south, Ukraine to the north, Hungary to the west, Serbia to the southwest, Moldova to the east, and ...

Slovakia Slovakia (; sk, Slovensko ), officially the Slovak Republic ( sk, Slovenská republika, links=no ), is a landlocked country in Central Europe. It is bordered by Poland to the north, Ukraine to the east, Hungary to the south, Austria to the s ...

Slovenia Slovenia ( ; sl, Slovenija ), officially the Republic of Slovenia (Slovene: , abbr.: ''RS''), is a country in Central Europe. It is bordered by Italy to the west, Austria to the north, Hungary to the northeast, Croatia to the southeast, an ...

Ukraine Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian inv ...

Serbia Serbia (, ; Serbian: , , ), officially the Republic of Serbia (Serbian: , , ), is a landlocked country in Southeastern and Central Europe, situated at the crossroads of the Pannonian Basin and the Balkans. It shares land borders with Hungar ...

and

Montenegro ) , image_map = Europe-Montenegro.svg , map_caption = , image_map2 = , capital = Podgorica , coordinates = , largest_city = capital , official_languages = M ...

.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 A diatom (New Latin, Neo-Latin ''diatoma''), "a cutting through, a severance", from el, διάτομος, diátomos, "cut in half, divided equally" from el, διατέμνω, diatémno, "to cut in twain". is any member of a large group com ...

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