Barbus lacerta is distinguished from other members of the Barbus lacerta group by having almost triangular gular region (vs. rectangular in other members of the B. lacerta group) and almost a longer anal fin; tip of the anal fin, when pressed to the body, reaches beyond the middle of the distance between the base of the last anal-fin ray and the lower caudal-fin origin, often to the caudal-fin base (vs. not reaching to middle of the distance); 0-3 (mode 2) scale rows between the tip of the anal fin and the base of the caudal fin (vs. 3-6, mode 5). It also differs from B. cyri by having a straight posterior anal-fin margin (vs. convex) and a narrow upper lip (its width 4-6 %HL vs. 7-9 % HL). Additional diagnostic characters include the following: long snout, its length 46-56% of body depth at dorsal-fin origin; eye diameter 2.5-3.1 times in snout length; 52-66+2-4 total scales along the lateral line; 35-48 (mode 39) predorsal scales; 25-32 (mode 28) circumpeduncular scales; length of caudal peduncle 1.7-2.0 times longer than depth; 60-70% of posterior margin of last unbranched dorsal-fin ray covered with denticles and median pad at lower lip small (Ref. 115584).

Description: Dorsal fin with 3-4 unbranched rays and 7-8 branched rays; anal fin with 3-4 unbranched rays and 5-6 branched rays (Ref. 115584).