Etheostoma lemniscatum is distinguished from all members of the complex by more posterior positioned anal fin (B6–B8, =332 vs. 317 or less); pectoral fin of nuptial males with dark, distal band confined to rays of the dorsal half or less of fin (vs. across all rays or all but 1–4 ventral rays); and nuptial males with dark and distinctly defined black bands on the distal margin of the caudal, anal, and second dorsal fins

(bands more diffuse in other species). Etheostoma lemniscatum is further distinguished from all members of the complex except E. marmorpinnum by higher modal (44 vs. 43 or less) number of lateral scale rows; and intermediate number of pored lateral line scales (26 or 28 vs. 22 in E. percnurum, and 34 in E. sitikuense). From E. marmorpinnum and E. percnurum by intermediate percentage of the first dorsal base area covered by scales (60% vs. 100% in E. marmorpinnum and 20% in E. percnurum); and an intermediate number of scales around caudal peduncle (24 vs. 25 and 23, respectively). From E. marmorpinnum and E. sitikuense by wider

distal band on anal fin (50% of fin height vs. 29–39%) and second dorsal fin (25% of fin height vs. 14–16%); and lack of marbling or tessellations in the medial portion of the second dorsal fin of nuptial males. From E.

marmorpinnum by lower percentage of belly covered by scales (10% vs. 60–80%); and wider, distal caudal–fin band (18% of fin length vs. 12–15%). From E. percnurum by lower number of caudal-fin rays (16 vs. 18); presence of strong tessellations on medial portion of caudal fin of nuptial males (vs. no tessellations); and

narrower distal band on the pectoral fin (range = 14–18% vs. 27–32%). Means of other measurements were also informative for distinguishing E. lemniscatum from members of the complex (Ref. 79849).