Trimerotropis pistrinaria Saussure

Common name - Barren land grasshopper (Heifer, 1972).

Geographic distribution - Alberta (Canada), Montana and the Dakotas to Mexico (Helter, 1972). In Colorado it is found primarily on the plains of the eastern part of the state (Alexander, 1941), and occasionally in the west.

Habitat - occurs on dry, gravelly plains and hillsides and on eroded barren lands (Heifer, 1972).

Food habits - a mixed feeder, feeding mostly on milkvetch and plants of the genus Hymenopappus (Criddle, 1933a: Joern, 1979b).

Eggs - pods contain 12 eggs. Color is tan, turning dark brown. Average egg length, 5.6 mm; average diameter, 1.3 mm (Onsager and Mulkern, 1963).

Nymph - five instars (Ramsey, 1964).

Adult - medium size. General color is tan, grey or reddish-brown with dark brown markings. Face is vertical. Antennae are slender. Dorsal posterior edge of pronotum is a right angle. Tegmina are tan with two definite bands basally and one spotted band near the apex. Wings are light yellow with a black band and clear apex. Outer and inner surfaces of hind femora have prominent bands on apical third; inner surface is yellow-orange. Hind tibiae are red with yellow on outer surfaces and toward bases. Male length, 30 mm; female, 35 mm.
 
Tegmen

Seasonal history - June to October. Overwinters in the egg (Ball et al., 1942).

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Biology of Common Colorado Grasshoppers
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