Synonyms and other taxonomic changes
Circotettix rabula Rehn & Hebard, 1906, summit of hills at Mammoth Hot Springs, Yellowstone National Park, Wyoming
Circotettix rabula ssp. altior Rehn, 1921, Cloudcroft, Otero County, New Mexico
Circotettix nigrafasciata Claassen, 1917, from Trego County, Kansas
Circotettix rabula ssp. nigrafasciata (Claassen) Rehn, 1921
Explanation of Names
The subspecies altior is found at high elevations in the Southern Rocky Mountains and New Mexico, and is somewhat smaller, shorter-winged, with a less-developed dark crossband on hind wings than the "typical" subspecies. It blends at lower elevation with ssp. rabula.
The subspecies nigrafasciata is a robust variant that is found on the Great Plains and usually has a very strongly developed dark band crossing the hind-wings.
Size
males about 30-45 mm
females about 30-50 mm
Smaller at high elevation, and largest on the Southern Great Plains.
Identification
A loud grasshopper of mostly exposed and eroded habitats. Colored in browns or grays and usually with a rather plain or speckled pattern. Tegmina may have spots aggregated or fused into dark cross bands. Hind wings are yellow, usually with a blackish cross band across outer half (sometimes faint or limited to veins). The hind tibiae are usually yellowish, sometimes brownish, or in south greenish or bluish.
Can easily be confused with Circotettix carlinianus & C. undulatus where they occur together if hind wings are not seen. C. carlinianus is somewhat stockier with the hind wings clear to blackish at the base and with black annal veins. C. undulatus usually has greenish to blue hind wings with the dark cross band usually absent or very weakly developed and positioned closer to the end of the wing. It usually has green to blue hind tibiae.
C. coconino replaces C. rabula to the south in New Mexico and Arizona, and is probably not specifically distinct. It differs primarily in having blue hind tibiae.
C. crotalum is similar, but is isolated further to the west in mountians in southern Nevada.
Any Trimerotropis species which might be confused can be separated easily if hind wings are seen (annal veins are not so obviously thickened, and wing shape and venation is different). Most similar is T. verruculatus, which usually also has most of the apical half of the hind wings dark and the base a richer and darker yellow.
Range
South central British Columbia to southwest Manitoba, south through Rocky Mountains, Great Plains, and Colorado Plateaus to western Oklahoma, the Texas Panhandle, southern New Mexico and central Arizona.
Habitat
Varied, but usually on or at the base of exposed eroded or rocky slopes. Sometimes sunny open rocky flats in Conifer (especially Pine) forest. Sometimes on exposed ridge tops and mountain tops. Gravel roads cutting across rock slides or cliff-faces are often gathering places for large numbers. Elevations occupied range from around 3000 ft to 11000 ft.
Life Cycle
Overwinters as eggs, with adults late spring or summer to freezing weather.
Remarks
This species is one of those that is hard to ignore when you are in the same area as it on a warm summer day. It crepitates loudly when it flies (making a loud interrupted and harsh buzzing that is punctuated by even louder snapping or popping sounnds). The males perform flight displays, during which they rise vertically high into the air and hover or bob up and down as they produce their crackling "song". Females are similarly loud, but do not often participate in the aerial display.
