Chortophaga viridifasciata (DeGeer)

 
Adult male Adult female

Common name - Northern green-striped locust (Blatchley, 1920).

Geographic distribution - found from Montana and British Columbia (Canada) to New Mexico and Utah. East to Ontario (Canada) and south to the Gulf Coast (Brooks, 1958). Its Colorado range is from the plains of the northern part of the state to the eastern mountain valleys (Hebard, 1 929).

Colorado Distribution Map

Habitat - dry, grassy areas and areas of low weeds (Blatchley, 1920; Hebard, 1928). In the Fort Collins, Colo., area it is commonly associated with wet areas.

Food habits - feeds principally on grasses but will eat forbs. Bluegrass is its preferred food. It also eats blue grama, western wheatgrass and sunsedge (Cantrall, 1943; Gangwere, 1961; Kumar et al., 1976).

Eggs - eggs are laid in large pods and are bound with whitish mucus. Each pod contains about 25 light-brown eggs arranged in three or four columns. Average egg length, 4.5 mm; average diameter, 1 mm (Onsager and Mulkern, 1963; Somes, 1914; Tuck and Smith, 1939).

Nymph - five instars (Cantrall, 1943).

Adult - medium size. Color is green or brown. Face is slightly slanted. Vertex is rounded. Antennae are red, flattened and rather short. A strongly pronounced median carina extends the entire length of the pronotum and is straight or slightly arched. Dorsal posterior margin of pronotum is an acute angle.
Green form: marginal field of tegmina is green, the remainder is grey-brown to colorless; a grey-brown wedge forms on the dorsal tegmina when folded. Abdomen is reddish-brown.
Brown form: apical halt of tegmina is darker, often with light spots.
In both forms the apical halt of the tegmina is membranous. Wings have the apical portion smoky and the basal half yellow-green. Hind tibiae are brown or light blue with white rings near the knees. Male length, 22 mm; female, 32 mm (Blatchley, 1920; Brooks, 1958).
In flight males make a rattling or shuffling sound. Females fly noiselessly, more directly and for greater distances (Blatchley, 1920).
 
Pronotum (Side view)

Oviposition - eggs are deposited in sand (Somes, 1914).

Seasonal history - first-instar nymphs hatch in August. Later-instar nymphs overwinter and adults appear in April or May and are present till July (Mulkern et al., 1964; Newton et al., 1954).

Abundance and importance - reported to be common in northern Colorado near Fort Collins and moderately abundant in the foothills. It sometimes increases in favored localities and does noticeable damage to crops (Gillette, 1904; Somes, 1914).

C. viridifasciata fact sheet from the Field Guide to Common Western Grasshoppers
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