Circotettix rabula Rhen and Hebard


Adult female

Common name - Wrangler grasshopper (Helfer, 1972).

Geographic distribution - British Columbia to Manitoba (Canada), Oklahoma, New Mexico and Arizona (Helfer, 1972). In Colorado the subspecies Circotettix rabula rabula is found from the foothills to timberline. C. rabula alterior lives at a higher altitude than C. rabula rabula (Hebard, 1929). C. rabula has been recovered from most areas of the state.

Colorado Distribution Map

Habitat - arid areas. Gravelly clearings among pines and dry clay banks facing the sun. Usually associated with rivers and ravines (Criddle, 1933a).

Food habits - a mixed feeder often eating moss and low-growing weeds. It specifically prefers loco, vetch, sandwort and bladderpod (Ball et all., 1942; Criddle, 1933a; Scoggan and Brusven, 1972; Ueckert, 1968).

Eggs - pale yellow. About 30 eggs are arranged in three or four columns within the pod. Egg length, 5.2 mm; diameter, 1.1 mm (Onsager and Mulkern, 1963).

Nymph - five instars (Scoggan and Brusven, 1972).

Adult - large. General color is pale greyish-brown with small darker markings. Face is vertical. Vertex is rounded. Antennae are slender. Dorsal posterior margin of pronotum forms a rounded right angle. Median carina is cut by two sulci. Tegmina are longer than the body and are speckled with spots sometimes forming indistinct bands. Wing disc is yellow with traces of a black band and spur. Lateral margin of wing is concave. Hind femora are banded with brown and yellow on the upper and inner surfaces. Hind tibiae are buff, sometimes tinged with blue. Male length, 45 mm; female, 52 mm (Ball et al., 1942).
 
Tegmen and wing

Oviposition - oviposition takes place on bare flat areas or rolling open hills (Onsager and Mulkern, 1963). Seasonal history - nymphs overwinter and emerge from May to mid-June. Adults appear in mid-June and can be seen until early August (Scoggan and Brusven, 1972).

Abundance and importance - rarely becomes numerous and seldom competes with domestic livestock (Scoggan and Brusven, 1972).

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Biology of Common Colorado Grasshoppers
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