''Alburnus danubicus'' is a species of

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or hor ...

in the genus ''

Alburnus ''Alburnus'' is a genus of fish in the family Cyprinidae, the carps and minnows. They are known commonly as bleaks. A group of species in the genus is known as shemayas. The genus occurs in the western Palearctic realm, and the center of diversi ...

''. It was known from coastal lakes in Romania and River Danube in Romania and Bulgaria. It is extinct and has not been recorded since 1943. In 2019, a somewhat mysterious specimen was caught from River Danube, at

Petrovaradin Petrovaradin ( sr-cyr, Петроварадин, ) is a historic town in the Serbian province of Vojvodina, now a part of the city of Novi Sad. As of 2011, the urban area has 14,810 inhabitants. Lying on the right bank of the Danube, across from t ...

, Serbia. It might have been ''Alburnus danubicus'', falsifying its status as an extinct species. Alternatively, it might have been an individual of ''

Alburnus mento ''Alburnus mento'' is a species of freshwater fish, a bleak in the family Leuciscidae. Its distribution is in subalpine lakes in Germany and Austria. Previously, the concept of ''A. mento'' was broader, and its distribution was thought to be ...

'' that moved down on the river very far from its native area in

Upper Austria Upper Austria (german: Oberösterreich ; bar, Obaöstareich) is one of the nine states or of Austria. Its capital is Linz. Upper Austria borders Germany and the Czech Republic, as well as the other Austrian states of Lower Austria, Styria, a ...

. The specimen was released alive after photography. This species is found in temperate, benthopelagic, freshwater. Distinguishable by its branched anal-fin rays and lateral line scales.

References

danubicus Taxa named by Grigore Antipa Fish described in 1909 Extinct animals of Europe Fish extinctions since 1500 {{Leuciscinae-stub