Key to species of Acanthocephala Laporte in America north of Mexico (Figs. 1–4) 1. Metatibiae broadly dilated for almost entire length, ending abruptly near apex (Figs. 5–8)............................ 2 1'. Metatibiae broadly dilated in basal 1/2, gradually narrowing beyond middle toward apex (Figs. 9–12).................. 3 2. Humeral angle of pronotum broadly rounded (Fig. 1), strongly extended laterally, elevated in posterior view (Fig. 13); metatibial expansions as in Figs. 5–6 .................................................................... A. declivis 2'. Humeral angles of pronotum more narrowly rounded, moderately extended laterally (Fig. 4), horizontal to slightly declivent in posterior view (Fig. 14); metatibial expansions as in Figs. 7–8 .......................................... A. thomasi 3. Metafemora of both sexes slightly expanded toward apex (occasionally parallel-sided or narrowed apically in males); both sexes lacking darkened areas beneath metacoxae on abdominal sternum 3 (second visible); antennal segment 4 red to yellow; metatibial expansions as in Figs. 9–10 ............................................................ A. terminalis 3'. Metafemora of males strongly incrassate, widest at middle, those of females slightly expanded; both sexes often with darkened areas beneath metacoxae on abdominal sternum 3; antennal segment 4 varying from concolorous with proximal segments to yellowish; metatibial expansion as in Figs. 11–12 ................................................... A. femorata .....................................................................................................

Published as part of Packauskas, Richard J., Sites, Robert W., Taylor, Steven J., Bundy, Scott, Bradshaw, Jeffrey D. & Mitchell, Paula Levin, 2011, Review of Acanthocephala (Hemiptera: Heteroptera: Coreidae) of America north of Mexico with a key to species, pp. 30-40 in Zootaxa 2835 on page 31, DOI: 10.5281/zenodo.200531