Melanoplus spretus Walsh, 1866

Rocky Mountain locust, Rocky Mountain grasshopper



Taxonomy & Nomenclature

Synonym/s: Caloptenus spretus Walsh, 1866


Conservation Status


Last record: 1902

IUCN RedList status: Extinct


The most numerous recent species, with a total population variously estimated at 12.5 trillion individuals, it went from ubiquitous to extinct within about 30 years. The breeding grounds where it laid its eggs on river banks were turned over by agricultural equipment, killing the eggs of this species and hence driving it into extinction.



North America (Canada & United States)


Biology & Ecology




For a photograph of a pinned specimen see:






Original scientific description:

Walsh, B. D. (1866). Grasshoppers and locusts. Pract. Entomol. 2: 1-5.


Other references:

American Museum of Natural History and Levon Biss (photographer). (2023). Extinct & Endangered: Insects in Peril. ABRAMS. 144 pp.

Atkins, A. (1984).  Harvest of grief: grasshopper plagues and public assistance in Minnesota, 1873-78. Minneapolis, USA: Minnesota Historical Society.

Bowell, Katie. (2010). The Rocky Mountain Locust. Blog post on The Fort Collins Museum & Discovery Science Center Blog. Accessed 5 May 2012.

Bruner, Lawrence. (date?). The Rocky Mountain Locust for the third report of the United States Entomological Commission. [incomplete citation]

Chapco, W. and Litzenberger, G. (2004). A DNA investigation into the mysterious disappearance of the Rocky Mountain grasshopper, mega-pest of the 1800s. Molecular Phylogenetics and Evolution 30(3): 810–814. [Abstract]

Cohn, Theodore J. (1994). The Use of Male Genitalia in Taxonomy and Comments on Lockwood's 1989 Paper on Melanoplus spretus (Walsh). Journal of Orthoptera Research 3: 59-63. [Abstract]

Garcia, M. 2000. "Melanoplus spretus" (On-line), Animal Diversity Web. Accessed September 10, 2011

Gurney, Ashley B. and Brooks, A. R. (1959). Grasshoppers of the Mexicanus group, genus Melanoplus (Orthoptera: Acrididae). Proccedings of the United States National Museum 110(3416): 1-100.

Hochkirch, A. (2014). Melanoplus spretus. The IUCN Red List of Threatened Species. Version 2014.1. ( Downloaded on 07 July 2014.

Hochkirch, A. 2014. Melanoplus spretus (errata version published in 2017). The IUCN Red List of Threatened Species 2014: e.T51269349A111451167. Accessed on 02 July 2022.

Holmes, Branden. (2021). What's Lost and What Remains: The Sixth Extinction in 100 Accounts (eBook). Self published.

Labandeira, Conrad C. (2012). Evidence for outbreaks from the fossil record of insect herbivory, pp. 269-290. In: Barbosa, Pedro, Letourneau, Deborah K. and Agrawal, Anurag. (eds.). Insect outbreaks revisited. Wiley-Blackwell.

Lockwood, Jeffrey A. (1989). Taxonomic status of the Rocky Mountain Locust: morphometric comparisons of Melanoplus spretus (Walsh) with solitary and migratory  Melanoplus sanguinipes (F.). Can. Entomol.  121: 1103-1109. [Abstract]

Lockwood, Jeffrey A. (1996). Phallic Facts, Fallacies, and Fantasies: Comments on Cohn's 1994 Paper on Melanoplus spretus (Walsh). Journal of Orthoptera Research 5: 57-60. [Abstract]

Lockwood, Jeffrey A. (2001). Voices from the Past: What We Can Learn from the Rocky Mountain Locust. 47(4): 208-215.

Lockwood, Jeffrey A. (2003). The death of the super hopper. High Country News, 3 February. Accessed 5 May 2012.

Lockwood, Jeffrey A. (2004). Locust: The Devastating Rise and Mysterious Disappearance of the Insect that Shaped the American Frontier. New York, USA: Basic Books.

Lockwood, Jeffrey A. (2010). The fate of the Rocky Mountain locust, Melanoplus spretus Walsh: implications for conservation biology. Terrestrial Arthropod Reviews 3(2): 129-160. [Abstract]

Lockwood, Jeffrey A. and DeBrey, L. D. (1990). A solution for the sudden and unexplained extinction  of the Rocky Mountain  Grasshopper, Melanoplus spretus (Walsh). Environ. Entomol.  19: 1194-1205. [Abstract]

Lockwood, Jeffrey A.; Thompson, Craig D.; Debrey, Larry D.; Love, Charles M.; Nunamaker, Richard A; and Pfadt, Robert E. (1991). Preserved Grasshopper Fauna Of Knife Point Glacier, Fremont County, Wyoming, U.S.A. Arctic and Alpine Research 23(1): 108-114.

Jeffrey A. Lockwood, Scott P. Schell, James K. Wangberg, Larry D. DeBrey, William G. DeBrey and Charles R. Bomar. (1992). Preserved Insects and Physical Condition of Grasshopper Glacier, Carbon County, Montana, U.S.A. Arctic and Alpine Research 24(3): 229-232. [Abstract]

Lockwood, Jeffrey A., DeBrey, L. D., Thompson, C. D., Love, C. M., Nunamaker, R. A., Shaw, S. R., Schell, S. P. and Bomar, C. R. (1994). Preserved insect fauna of glaciers of Fremont County in Wyoming: Insights into the ecology of the extinct Rocky Mountain locust.  Environ. Entomol.  23: 220-235. [Abstract]

Packard, A. S. (1877). Report on the Rocky Mountain locust and other insects now injuring or likely to injure field and garden  crops in the Western  States and Territories. 9th Report U. S. Geol. Surv. Terr. pp. 589-809.

Pellegrini, Evan J. et al. (2022). A 14,100 cal B. P. Rocky Mountain locust cache from Winnemucca Lake, Pershing County, Nevada. Journal of Archaeological Science: Reports 46: 103704.

Riley, C. V. (1875). The Rocky Mountain locust-Caloptenus spretus Thomas.  7th Annual Report on Noxious  and Beneficial  Insects of Missouri  pp. 121-196.

Riley, C. V. (1877). The Locust Plague in the United States, Being More Particularly a Treatise on the Rocky Mountain Locust or So-Called Grasshopper, as It Occurs East of the Rocky Mountains, with Practical Recommendations for Its Destruction. Chicago: Rand, McNally and Co.

Ryckman, Lisa Levitt. (1999). The Great Locust Mystery: Grasshoppers That Ate The West Became Extinct. Colorado Millennium 2000. Denver Rocky Mountain News, June 22, 1999. Retrieved 10-Sep-2011.

Bruce D. Sutton, David A. Carlson, Jeffrey A. Lockwood and Richard A. Nunamaker. (1996). Cuticular Hydrocarbons of Glacially-Preserved Melanoplus (Orthoptera: Acrididae): Identification and Comparison with Hydrocarbons of M. sanguinipes and M. spretus. Journal of Orthoptera Research 5: 1-12.

Thomas, C. (1865). Insects injurious to vegetation in Illinois.  Trans. Illinois  State Agric. Soc. 5: 401-468.


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