Pronotum as broad, or almost as broad, as base of elytra. Very dark. Elytra have irregular punctures, and each elytron has three indistinct longitudinal ridges. Pronotum has three blunt lateral teeth on each side. Antennae have 12-13 segments. Female much larger than male. The former is reported to be flightless, or nearly so. Males are attracted to lights.
Compare Prionus pocularis, which is more brown, base of pronotum narrower, elytra more punctate, eyes closely spaced, female metasternum hairy.
Eastern North America: Quebec, west to Ontario, Minnesota, Oklahoma. South to Florida formerly, but no recent records for that state.
June-September (Northeast). June-August (North Carolina mountains). July, especially in North Carolina Piedmont.
Adults eat foliage, sometimes damage fruit trees, grape vines.
Eggs are inserted into ground (or under litter) in groups. Larvae tunnel downward to feed on living roots of a variety of trees and shrubs. At first they may feed on bark, but then proceed to hollow out small roots. Pupation occurs in spring, about 10 cm under the ground. Life cycle probably three years.
Dillon, p. 577, plate LVII (1)
Yanega, p. 27, fig. 9a-b (2)
Arnett et al., p. 295, fig. 690 (3)
Papp, p. 203, fig. 684 (4)
Swan and Papp, p. 442, fig. 928 (6)
Baker, p. 200--description (8)