Blue-grama-specialist
Guides
Cordillacris
Cordillacris is a genus of slant-faced grasshoppers in the family Acrididae, established by Rehn in 1901. The genus contains two described species: Cordillacris crenulata (crenulated grasshopper) and Cordillacris occipitalis (spot-winged grasshopper). Both species are small, slender grasshoppers of western North American grasslands. The genus is characterized by distinctive wing patterns and coloration that distinguish it from related genera.
Cordillacris crenulata
Crenulated Grasshopper, Crenulatewinged Grasshopper
Cordillacris crenulata is a small, slender slant-faced grasshopper native to western North American grasslands. It is distinguished by the diagnostic crenulate (scalloped) brown stripe on each tegmen. The species is a specialist feeder on blue grama grass and reaches greatest abundance in shortgrass and desert prairies. Though occasionally present in outbreak populations, its small size and typically low densities limit its economic impact.
Opeia obscura
obscure grasshopper
Opeia obscura, commonly known as the obscure grasshopper, is a slant-faced grasshopper in the family Acrididae. It is widely distributed across the grasslands of North America and into Central America. The species is a specialist feeder on blue grama grass (Bouteloua gracilis) and is considered a late-hatching grasshopper, with eggs typically hatching in June. While it can contribute to rangeland damage during grasshopper outbreaks, populations rarely reach outbreak densities independently.
Trachyrhachys aspera
Finned Grasshopper
Trachyrhachys aspera, commonly known as the finned grasshopper, is a medium-sized band-winged grasshopper native to the shortgrass prairie ecosystems of western North America. This species exhibits strong habitat fidelity to blue grama grass (Bouteloua gracilis) dominated grasslands, where it functions as a subdominant member of grasshopper assemblages. The species is notable for its late-season phenology, hatching approximately four weeks after the sympatric Trachyrhachys kiowa, and for its highly specialized diet consisting almost exclusively of blue grama grass. Despite its potential economic impact as a forage competitor with livestock, populations have remained chronically low with no documented outbreak events.
Trachyrhachys kiowa
Kiowa grasshopper, ash-brown grasshopper
Trachyrhachys kiowa is a medium-sized band-winged grasshopper inhabiting shortgrass and mixedgrass prairies of western North America. It feeds almost exclusively on grasses and sedges, particularly blue grama, and can become an economically damaging component of outbreak populations. The species is known for its dispersive behavior and intermediate hatching phenology, emerging two to three weeks after early-hatching species like the bigheaded grasshopper.