Heliaula rufa
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Geographic range of Heliaula rufa (Scudder) |
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Fig. 1, adult male: BL 12-18 mm, FL 8.5-10.5 mm, AS 19-22 |
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Fig. 2, adult female: BL 18-25 mm, FL 10.5-13 mm, AS 20-23 |
Species
Rufous grasshopper
Heliaula rufa (Scudder)
Subfamily Gomphocerinae
Identification
The rufous grasshopper is a small and robust species, typically light brown to nearly pink in color. The head may sometimes be nearly white and contrasting with the body color. It lacks any discernible markings on the head or pronotum. The outer face of the hind femur usually has at least two faint dark bands present, but these may occasionally be lacking. The hind tibiae are reddish orange to nearly red. The tegmina are unicolorous but most often with small spots scattered throughout. The antenaae are filiform. The posterior edge of the pronotum is intermediate between a right angle and a curve, and thus, its subfamily-level placement has long been controversial between bandwings and slantfaces. The rufous grasshopper superficially resembles Ageneotettix deorum and Aulocara elliotti. It can be differentiated from A. deorum by the lack of an hourglass shaped marking on the dorsal pronotum and by its lighter brown color. It differs from the Aulocara species in lacking markings on the dorsal pronotum and in having reddish tibiae rather than blue.
Distribution and habitat
The rufous grasshopper occurs from southern Arizona and southwestern Texas through Colorado into western Nebraska and southeastern Wyoming. It inhabits rocky and gravelly soils, especially on hillsides and on small hills. In Arizona it occurs in the upper Sonoran Zone at elevations of 2,000 to 7,000 feet. There it is found on slopes or small hills with thin, rocky, or gravelly soils. In Texas it is encountered along river cliffs and outcrops on plains, usually with gravelly soils. It is generally an uncommon species.
Economic importance
Because it is uncommon and local, it is not expected to be of any economic importance. It reportedly can be common in parts of southeastern Colorado.
Food preferences
This grasshopper is a grass feeder that prefers gramas but will also feed on threeawn.
Dispersal and migration
The dispersal ability of the rufous grasshopper has not been studied.
Hatching
The hatching period of this species has not been studied, but it is likely in the intermediate hatching group.
Nymphal development
The nymphal development of the rufous grasshopper has not been studied in detail. It most likely has five nymphal instars.
Adults and reproduction
Adults have been recorded to occur from June to October. In Colorado adults are most common from late July to late September.
Population ecology
The population ecology of this grasshopper has not been studied in detail. It is nearly always local in distribution and only common within limited areas.
Daily activity
The daily activity of this grasshopper has not been studied.
Source and date
University of Nebraska by Mathew L. Brust March 2007
Selected references
Alexander, G. 1941. Keys for the identification of Colorado Orthoptera. University of Colorado Studies, Series D. 1: 129-164.
Ball, E. D., E. R. Tinkham, R. Flock, and C. T. Vorhies. 1942. The grasshoppers and other Orthoptera of Arizona. Arizona Agriculture Experiment Station Technical Bulletin 93: 255-373.
Capinera, J. L. and T. S. Sechrist. 1982. Grasshoppers (Acrididae) of Colorado: Identification, biology and management. Colorado State University Experiment Station Bulletin No. 5848. 161 pp.
Fry, B., A. Joern, and P. L. Parker. 1978. Grasshopper food web analysis: use of carbon isotope ratios to examine feeding relationships among terrestrial herbivores. Ecology 59: 498-506.
Hebard, M. 1929. The Orthoptera of Colorado. Proceedings of the Academy of Natural Sciences, Philadelphia 81: 303-425.
Helfer, J. R. 1987. How to Know the Grasshoppers, Crickets, Cockroaches and Their Allies. Dover Publications Inc. New York, New York. 363 pp.
Joern, A. 1979. Feeding patterns in grasshoppers (Orthoptera: Acrididae): factors influencing diet specialization. Oecologia 38: 325-347.
Kumar, R., R. Lavigne, J. Lloyd, and R. Pfadt. 1976. Insects of the Central Plains Experiment Range, Pawnee National Grassland. Wyoming Agriculture Experiment Station Sci. Monog. 32: 1-74.
Otte, D. 1981. The North American grasshoppers, Volume I, Acrididae: Gomphocerinae and Acridinae. Harvard University Press, Cambridge, Massachusetts. 368 pp.
Tinkham, E. R. 1948. Faunistic and ecological studies on the Orthoptera of the Big Bend Region of Trans-Pecos Texas, with especial reference to the Orthopteran zones and faunae of midwestern North America.
