Size: 12-15.8mm

Seasonality: April to October

Distribution; USA, CAN, MEX, excluding most eastern US states and Canada east of Quebec.

Information: Euryderus grossus is the only species in its genus, they are sexually dimorphic; males have wide protarsi with specialised pads underneath, while females' protarsi are neither widened, nor specialised. The protibiae are quite broad to ease the carabid's ability to dig into both hard and soft soils alike.

Description: body: broadly-oblong, robust. Dorsal and ventral colouration semi-glossy black with reddish hue. Head quite broad; face short, mandibles curved, not overly large. Dorsal surface of the head is relatively smooth, slightly wrinkled, with a long, narrow "[" shaped depression. Labrum half as long as wide. Palps pale orange, antennae short and narrow; pale orange to piceous. Antennal pubescence begins on the third antennomere from the pedicel. Pronotum broad, base as wide as width of elytral shoulders, lateral pronotal margins upturned, slowly curve inwards towards the head. Hind angles squared; 9 long, pale setae should be found on the pronotal lateral margins. Minimally punctate along dorsal basal margins, rest of disk smooth, median line shallow. Basal margin of pronotum overlapping with base of elytra. Elytra sparsely coated in short, fine, pale setae, inconspicuous without a hand lens or scope. Elytral lateral margins thin, upturned; 8-9 deep, well-defined striae per elytron. Intervals between striation 2 and 3, 4 and 5, 6 and 7 lined with three to four large fovea. Apical region of elytra rounded. Ventral: mostly semi-glossy black with rufous hue, legs and other ventral surfaces dotted with long, pale setae. Protibiae broad, specialised for digging.