From the Red Book of Czech molluscs – Where Does Theodoxus danubialis Live?

Beran L.

Two species of Theodoxus have been recorded on the territory of the Czech Republic. While Theodoxus fluviatilis, which was known only from the Elbe River in Litoměřice, died out more than 70 years ago, T. danubialis still occurs in the lower part of the Dyje and Kyjovka rivers in South Moravia. A high population of this gastropod was found there in 2008 and 2009, but T. danubialis is still considered critically endangered in the Czech Republic due in part to the restriction of the area of its occurrence to the Dyje and Morava rivers and its tributaries in comparison with the past.

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