Key to species of male Zeadolopus of the continental United States and Canada
1. Abdominal sternite III with two large foveae at anterior margin...... Z. bifoveolatus Daffner
– Abdominal sternite III without large foveae ................................................................................ 2
2(1). Paired apices of median lobe of aedeagus short and rounded (Fig. 15); parameres broad .......... .............................................................................................................. Z. rubricornis Daffner
– Paired apices of median lobe inwardly curved (Fig. 12, 14); parameres narrower .................... 3
3(2). Metatibia more robust, widened near middle; inverted internal sac with a broad, fan-like structure apically (Fig. 12) ...................................................................... Z. egenus (LeConte)
– Metatibia more slender, not widened near middle; inverted internal sac without a broad, fanlike structure (Fig. 14)..................................................................... Z. oklahomensis Daffner