The species of Araecerus are variable and difficult to characterize. Araecerus fasciculatus (DeGeer) has the following features: dorsum without tubercles, tufts, crests, or costae; antennal club very slender, asymmetrical, each article tapering at both ends; prosternal antecoxal strip not linear, roughened with fine microsculpture and not coarsely punctured; pronotum finely reticulate-punctate; lateral carina not reaching supracoxal suture, frequently weakly upturned at apex; elytral pubescence tessellate dark and light brown and gray plus a small, paler postscutellar spot; legs with tibiae relatively long and slender, with four (sometimes very vague) dark annuli or spots often best developed on hind legs; males with fore tibiae not denticulate along ventral length, without an apical spur, and not bent or hooked; male fore tarsus with basal article elongate, narrow, setose ventrally, not bent or arched upward in center, about as long as articles 2-5 combined; male mesocoxa without a small tooth mesal to the attachment of the trochanter; male internal sac with a group of about 5 small sclerites, the two largest triangular.