''Schistocerca cancellata'' is a species of

locust Locusts (derived from the Vulgar Latin ''locusta'', meaning grasshopper) are various species of short-horned grasshoppers in the family Acrididae that have a swarming phase. These insects are usually solitary, but under certain circumst ...

in the subfamily

Cyrtacanthacridinae The Cyrtacanthacridinae are a subfamily of Orthoptera: Caelifera in the family Acrididae. They are sometimes referred-to as bird locusts, ''criquets voyageurs'' in French-speaking Africa, and ''Knarrschrecken'' in German. It includes species o ...

. It is the major swarming species in subtropical South America. This species shows typical locust phase polymorphism. Solitarious nymphs are green, but gregarious ones are yellow with a black pattern. There are morphological differences between solitarious and gregarious adults. For many years the two phases were believed to be different species and the gregarious form was mistakenly identified as S. paranensis. The solitary phase is found in South America between 18°S and 35°S. Plagues originate in a desert and semi-desert zona permanente in NW Argentina, SE Bolivia and W Paraguay, when good rains allow successful breeding, followed by gregarisation. Swarms of gregarious adults may then migrate into crop growing regions.

Economic importance

''Schistocerca cancellata'' is polyphagous, damaging a wide range of crops and forage plants. It is probably the most economically damaging of all the locust species. It was estimated that in 1933 that locusts destroyed 2 million tons of cereals and other annual crops. High levels of damage have also been recorded in Uruguay and Brazil.

References

COPR (Centre for Overseas Pest Research) (1982), The Locust and Grasshopper Agricultural Manual {{taxonbar, from=Q6122397 Cyrtacanthacridinae Orthoptera of South America Insects described in 1838