Creteuchiloglanis longipectoralis is distinguished from all other congeners by its more slender body (depth at anus 7.8–8.1% SL vs. 9.4–14.7%) and its shallower head (depth 7.2–8.8% SL vs. 9.0–14.5%). It is further distinguished from C. brachypterus by having a pectoral-fin length 98.1–120.9% Pt–Pl distance (vs. 65.8–78.7%), i,5 dorsal-fin rays (vs. i,6), shorter post-adipose distance (7.0–8.9% SL vs. 9.1–11.3%), and by the absence (vs. presence) of pale patches on body. It is further distinguished from C. macropterus by having i,5 dorsal-fin rays (vs. i,6) and by the absence (vs. presence) of pale patches on body. It is further distinguished from C. gongshanensis by having a deeper caudal peduncle (35.6–56.7% caudal-peduncle length vs. 23.5–29.7%; 6.5–8.9% SL vs. 3.8–4.6%). It is further distinguished from C. kamengensis by having i,5 dorsal-fin rays (vs. i,6), by having the tip of the pelvic fins reaching beyond the origin of adipose fin (vs. not reaching beyond the origin of the adipose fin), and by having the tip of pectoral fin reaching beyond the insertion of dorsal fin (vs. not reaching beyond the insertion of dorsal fin) (Ref. 87311).