Adults of Rhagnoycha recta are somewhat variable in appearance. Typically, they are dark brown to black with yellow to yellow-brown margins on the pronotum and elytra, though a dark form with mostly or entirely black pronotum and/or elytra occurs, especially among more northern specimens. Legs may be entirely dark barring yellow knees, or may have entirely yellowish tibiae and tarsi. Antennae are 60 to 70 percent of body length, which ranges from 5 to 7 mm.