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The head is wider than long or approximately as long as wide. The posterior portion of the head, behind the eyes, has anastamosing or transverse sculpture. Ocelli are present, and ocellar setae pair 1 is absent, pair 2 is anterolaterad to the anterior ocellus, and pair 3 varies in position. There are also 4 to 6 pairs of postocular setae arranged caudad from the posterior ocellus to the lateral margin. The antennae are 7 or 8 segmented, with trichomes on segments 3 and 4, whorls of microtrichia on segments 3 to 6, a row of subapical setae on each of segments 3 to 5, setae on the distal half of segment 6, and inner and outer sense cones on segment 6. The pronotum is rectangular and has varying numbers of discal setae, 2 pairs of well-developed posteroangular setae, and usually 3 pairs of posteromarginal setae. The legs are spinose and well developed. All tarsi are 2 segmented. Macropterous and brachypterous forms occur in this genus. The forewings are covered with microtrichia. In macropterous forms, the hind vein has a continuous row of setae and the fore vein may have a continuous row, or the distal half may have 2 to 8 intermittent setae. The hindwing often has a grayish brown longitudinal stripe. In brachypterous forms, the wing does not extend past abdominal segment 1. Sculpture on the abdominal tergites varies with species, and tergite 2 has 3 or 4 lateral setae. A posteromarginal comb on tergite 8 may be complete, medially incomplete, or absent. A pair of submarginal ctenidia extend mesad of the spiracle on tergite 8. Tergite 9 has 1 or 2 pairs of campaniform sensilla. Sternite 1 may or may not have anterolateral setae, and accessory setae may be present or absent (Nakahara, 1994).