Etheostoma sitikuense is distinguished from all members of the E. percnurum species complex by more pored lateral-line scales (34 vs. 28 or fewer); intermediate anal-fin band width (range = 33–39% vs. 49–58% in E. lemniscatum and E. percnurum and 29–33% in E. marmorpinnum); fewer transverse scale rows (15 vs. 16); shorter pectoral (P1L, =240 vs. 245 or greater) and pelvic (P2L, =180 vs. 197 or greater) fins;

and wider (BW, =80 vs. 69 or less), deeper (BD1, =178 vs. 173 or less and BD2, =158 vs. 153 or less) body. E. sitikuense is further distinguished from E. percnurum and E. lemniscatum by narrower distal band on

the second-dorsal fin (range = 9–16% of fin height vs. 23–25%). From E. percnurum and E. marmorpinnum by distal caudal-fin band width (range = 15–18% of fin length vs. 12–15% in E. marmorpinnum and 17–25% in E. percnurum); percentage of area along first-dorsal fin base scaled (70% vs. 20% in E. percnurum and 100% in E. marmorpinnum); and intermediate number of scales around caudal peduncle (24 vs. 23 or 25,

respectively). From E. lemniscatum and E. marmorpinnum by fewer lateral-line scales (43 vs. 44). From E. percnurum by diffuse marbling or stippling in medial portion of second dorsal fin of nuptial males (vs. uniformly dusky); tessellations in medial portion of caudal fin of nuptial males (vs. uniformly dusky); narrower distal band on pectoral fin (range = 14–20% vs. 29–32%); and fewer caudal-fin rays (15 vs. 18); and from E. marmorpinnum by lower percentage of the belly covered by scales (10% vs. 60–80%). Means of other measurements were also informative (Ref. 79849).