Arenivaga tonkawa Hebard 1920

Arenivaga tonkawa, the tonkawa sand cockroach, is a species of cockroach in the family Corydiidae. It is found in Central America and North America.

Male. Measurements. Holotype stand-in TL = 20.2 mm, GW = 8.9 mm, PW = 5.92 mm, PL = 4.28 mm, TL/GW = 2.27, PL/PW = 0.72. EW = 0.15 mm; OW = 0.40 mm. Among paratypes range of TL 15.7–25.5 mm; range of GW 7.3–12.5 mm; range of PW 5.02–8.55 mm; range of PL 3.83–5.25 mm. Head. Two ocelli very large, ovoid and protruding (0.50 × 0.40 mm); vertex dark brown, with small ridges between apices of eyes extending on to ocellar tubercles; interocellar space concave, dark brown grading to medium brown medially; two oval indentations laterally at base of interocellar space. Frons light brown, concave; bound on either side by ridges extending from inner apex of ocelli outwards to lateral edges of clypeus; scattered long setae on ridges. Anterior portion of frons light brown, bulbous; clypeal suture demarcates light brown anteclypeus. See Fig. 147d. Pronotum. Pronotum translucent waxy beige; variable length orange-brown setae along anterior margin; dorsal surface of pronotum covered with short orange-brown setae that are denser and longer anteriorly and laterally; pronotal pattern medium orange-brown “panther face”, with little detail and no aura; within the species pronotal pattern runs from light brown through every shade to dark brown, some with considerable discernible detail, but always with no aura. See Fig. 147c. Body. Wing brace present. Legs and body medium orange-brown; subgenital plate asymmetrical with posterior edge emarginated, rounded apices. See Fig. 147b. Forewings. Wings extended beyond abdominal apex (up to ~35% of total wing length); light orange-brown with darker blotches; within the species color variable from light orange-brown, to dark orange-brown, always blotchy; surface opaque and matte. See Fig. 147a. Genitalia. Right dorsal phallomere composed of bulbous lightly sclerotized lobe, articulated with right ventral phallomere on lateral side; central field lightly sclerotized; medial margin sclerotized, smooth, with two adjacent spines at posterior end; spines may vary in size and exact placement from specimen to specimen. Small central sclerite smooth, concave, with punctate, posteriorly pointing lip at anterior end. Right ventral phallomere extends from articulation into smooth lobe, punctate towards point of articulation; narrows anteriorly in punctate corrugations; after narrow gap, broad, punctate, posteriorly curving arm extending to depth of rest of phallomere. Genital hook with narrow pointed head and short hook; arm short with distinct bend. See Fig. 148.

This species has a disjunct distribution comprising Texas, western Oklahoma and northeastern Mexico in one part, and Arizona, far southern California, southern Nevada, southern Utah, western Colorado and northwestern Mexico in the other part. See Fig. 149.