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The difference between grasshopper and locust:
Locusts and grasshoppers are the same in appearance, but locusts can exist in two different behavioural states (solitary and gregarious), whereas most grasshoppers do not. When the population density is low, locusts behave as individuals, much like grasshoppers. However, when locust population density is high, individuals undergo physiological and behavioural changes, known as phase polyphenism, and they form gregariously behaving bands of nymphs or swarms of adults.In addition to changes in behaviour, the phase change may be accompanied by changes in body shape and colour, and infertility, physiology and survival. These changes are so dramatic in some species that the swarming and non-swarming forms were once considered to be different species. The scale of population increase and migrations also distinguish those species known as locusts from grasshoppers.
The distinction between locusts and grasshoppers is often not clear-cut, as the extent to which different species exhibit gregarious phase characters is graded. The migratory locust has all of the features associated with phase change - differences in body shape and colour, fertility and gregarious behaviour in both the nymph and adult life stages, forming dense bands and swarms. The Australian plague locust also forms dense nymph bands and adult swarms but does not exhibit changes in body colour. Spur-throated locust nymphs do not form bands and the adults do not lay eggs gregariously, but they do form dense swarms.
Some species that are called grasshoppers, such as Austroicetes cruciata, Oedaleus australis and Peakesia spp. can form loose swarms at high densities, but do not generally migrate long distances as locusts do.
Classification:
Locusts belong to the same order as grasshoppers, katydids and crickets - the Orthoptera (derived from the Greek words orthos meaning straight or rigid and ptera meaning wing).In Australia, there are over 2,800 species of Orthoptera and over 700 species of locusts and grasshoppers. Many species are yet to be scientifically described.
1. Australian plague locust Chortoicetes terminifera - Australia
2. Bombay locust Nomadacris succincta - India, South-east Asia
3. Brown locust Locustana pardalina - Southern Africa
4. Desert locust Schistocerca gregaria - deserts from West and North Africa to western India
5. South American locust Schistocerca cancellata - South America
6. Central American locust Schistocerca piceifrons - Central America
7. Italian locust Calliptamus italicus - semi-deserts and steppes from Morocco and central Europe to Central Asia
8. Migratory locust Locusta migratoria - Asia, Africa and eastern Europe
9. Moroccan locust Dociostaurus maroccanus - semi-deserts and steppes from Morocco through North Africa and the Middle East to Central Asia
10. Red locust Nomadacris septemfasciata - southern and south central Africa
11. Rocky Mountain locust Melanoplus spretus – extinct
12. Spur-throated locust Australis procera - Australia
13. Tree locusts: Anacridium spp.
14. Egyptian locust, Anacridium aegyptium, Europe, North Africa and Central Asia
15. Sahelian tree locust, Anacridium melanorhodon, Sahelian vegetation zone
16. Sudan tree locust, Anacridium wernerellum, Sudanian vegetation zone
17. Mato Grosso locust, Rhammatocerus schistocercoides, Brazil
18. Yellow-spined bamboo locust, Ceracris kiangsu - Indo-China, eastern China
19. High plains locust, Dissosteira longipennis-- North America. Formed large swarms as recently as the 1930s, but never since.
20. Senegalese grasshopper Oedaleus senegalensis - often displays locust-like behaviour in the Sahel region
21. Sudan plague locust Aiolopus simulatrix - occasionally behaves like a locust in eastern Sudan
22. Pallid-winged grasshopper Trimerotropis pallidipennis--occasionally exhibits swarming behaviour in western North America, most recently in Nevada in 2019.
Locusts belong to the same order of insects like grasshoppers, katydids and crickets - the Orthoptera.
locust plague can be very dangerous. locust performance testing: a locust can eat as much food as its weight, So a swarm of locusts will eat 423 million pounds of crops every day.
