About Alburnus arborella (Bonaparte, 1841)
Alburnus arborella can be distinguished from related species found around the Adriatic Sea by the location of its anal fin origin: it lies directly underneath the 4th to 8th branched dorsal fin rays. Its anal fin has between 13 and 16 and a half branched rays. The ventral keel is exposed, and is covered in scales either partially or completely. In living individuals, a faint stripe runs along the lateral line, and this stripe becomes more distinct in preserved specimens. The pectoral fin does not reach all the way to the base of the pelvic fin. The mouth points upwards. The maximum standard length recorded for this species is 12.7 cm (5.0 in).
Alburnus arborella is endemic to rivers that drain into the northern Adriatic Sea, ranging from the Chienti drainage basin in Marche to Istria, with an isolated population occurring in the Zrmanja basin in Croatia. This fish has been introduced to other areas of Italy, including northern Sardinia, as well as to additional parts of Croatia. It inhabits a broad variety of aquatic environments, from large subalpine lakes to lowland rivers and small streams. It can also be found in human-made habitats such as reservoirs and canalised rivers.
