Phase-polyphenism
Guides
Cyrtacanthacridinae
Bird Grasshoppers, bird locusts, criquets voyageurs, Knarrschrecken
Cyrtacanthacridinae is a subfamily of short-horned grasshoppers (Acrididae) commonly known as bird grasshoppers or bird locusts. The subfamily includes some of the world's most economically important locust species, including the desert locust (Schistocerca gregaria) and the red locust (Nomadacris septemfasciata), which undergo density-dependent phase polyphenism. Members are characterized by a prominent peg or tubercle between the forelegs. The subfamily has a worldwide distribution concentrated in tropical and subtropical regions.
Melanoplus rugglesi
Nevada Sage Grasshopper
Melanoplus rugglesi is a medium-sized spur-throated grasshopper endemic to the cold desert shrublands of the western United States. The species exhibits pronounced phase polyphenism, with solitary and migratory forms differing in body size, wing length, and coloration. Named in honor of entomologist Arthur G. Ruggles, this grasshopper is notable for its extreme migratory behavior and extended outbreak dynamics, with populations persisting at high densities for multiple years.
Melanoplus spretus
Rocky Mountain Locust
Melanoplus spretus, the Rocky Mountain Locust, was a species of locust that ranged through the western United States and parts of Canada until the late 19th century. It was one of the most destructive agricultural pests in North American history, forming swarms of unprecedented size—one 1875 swarm was estimated at 198,000 square miles. The species is now extinct, last observed in the early 1900s. It is considered by some authorities to represent a gregarious, migratory phase of Melanoplus sanguinipes rather than a distinct species.