Chrysobrycon yoliae can be easily diagnosed from its congeners by having the following characters: anterior tip of pelvic bone situated anterior to the fifth rib (vs. situated posterior to the fifth rib); 20-26 dentary teeth (vs. 12-19 in C. eliasi, 11-19 in C. hesperus, and 12-18 in C. myersi); terminal lateral-line tube present between caudal-fin rays 10 and 11 (vs. absent, except in C. eliasi). It differs from C. eliasi and C. myersi by the having teeth on third pharyngobranchial (vs. the absence of teeth on this bone). It is also distinguished from C. eliasi by the dorsal-fin origin situated vertically between anal-fin rays 5 to 7 (vs. situated vertically between anal-fin rays 8 to 10), the posterior extent of the ventral process of quadrate reaching the vertical through posterior margin of symplectic (vs. not reaching the vertical through posterior margin of symplectic), dorsal-fin to adipose-fin length 26.8-28.8% SL (vs. 23.9-26.8% SL), and body depth at dorsal-fin origin 34.4-42.2% SL (vs. 24.1-34.5% SL). It can be further distinguished from C. hesperus by lacking minute bony hooks on distal portion of the anal-fin rays in adult males (vs. present on distal portion of almost all anal-fin rays). It differs from C. myersi by having dorsal-fin to pectoral-fin length 47.3-53.1% SL (vs. 43.0-46.1% SL), the eye to dorsal-fin origin length 49.6-55.0% SL (vs. 45.8-49.2% SL), the upper jaw length 44.9-48.1% HL (vs. 48.9-55.0% HL), 15-16 circumpeduncular scales (vs. 17-19), and 26-28 branched anal-fin rays (vs. 33-39) (Ref. 96866).

Description: dorsal-fin rays ii,8; anal-fin rays iv-v,26-27; pectoral-fin rays i,8-11; pelvic-fin rays i,7 (Ref. 96866).