Couplet 23

23a:  Elytra shortened and widely divergent at apex (except in Lichnanthe lupina), not covering pygidium; eighth morphological abdominal segment with spiracle

Glaphyridae   p. 411

23b:  Elytra not shortened or widely divergent at apex, pygidium exposed or not (Figures 26-29C,D, 26-30, 26-32, 26-33, 26-34); eighth morphological abdominal segment lacking spiracle