[2] The maximum published weight is 1.1 kg (2 lb 7 oz),[3] although the largest rod caught fish, caught in Slovakia, weighed 2.2 kg (4 lb 14 oz) and measured 53 cm (21 in) in length.

[4] The males develop nuptial tubercles above the anal fin during the spring spawning season.

Its range spans from the Netherlands in the west to Russia and Georgia in the east.

[2] It spawns in Spring, once the ice has thawed, in shallow reedy bays onto the vegetation and the young fish stay in these areas although the adults move into open water to feed.

[1] The Python-based application server Zope is not named after this species; it is an acronym for "Z Object Published Environment".