Ukrainian Brook Lamprey Identification Guide

Key identification features

• Small body, generally 12-20 cm long as an adult
• Two dorsal fins set close together toward the rear of the body
• Small oral disc with reduced, blunt teeth since adults stop feeding after transforming
• Dark grey-brown coloration above, lightening to a pale belly
• Slender, scaleless, eel-like build with no paired fins
• Larvae are eyeless and toothless, living buried in silty stream substrate for several years

Common look-alikes

• River lamprey is considerably larger, remains parasitic as an adult, and shows stronger, more developed oral disc teeth.
• European brook lamprey overlaps in parts of its range and looks very similar, so the two are best told apart by subtle tooth-row arrangement and precise river system.
• Larval lampreys of larger parasitic species look almost identical at the ammocoete stage, so confirming range and eventual dorsal fin spacing after transformation is important.

Where you'll see one

This species lives entirely in fresh water, favoring small rivers and streams within the Dniester, Dnieper, and other Black Sea drainage basins across Ukraine and neighboring parts of Eastern Europe, usually over sandy or silty stream bottoms.