Dactyloscopus byersi differs from Dactyloscopus heraldi in a number of features: one row of scales above the curved portion of the lateral line (vs. none); A 31-35, modally 34 (vs. 29-33, modally 32); upper lip fimbriae 13-18, modally 15 (vs. 11-14, modally 12); preopercular sensory pores increases in number with size, but more present in D. byersi of comparable sizes; chevron markings prominent on the side posteriad (vs. weak or absent) and absence of dark bars on the dorsum (vs. present) (Ref. 82814).