The Rocky Mountain Locust is responsible for what is the largest locust swarm in recorded US history. In 1874 the swarm emerged from the rocky mountains and swept across the Midwest, blocking out the sun and covering entire states, leaving farms completely stripped of vegetation. Learn all about the 1874 swarm, and the insect that it was composed of, on this episode of Insectview!


Sources: 
https://books.google.com/books?id=kSU4AQAAMAAJ&pg=RA1-PA25#v=onepage&q=caloptenus&f=false

 The fate of the Rocky Mountain locust, Melanoplus spretus Walsh: implications for conservation biology  ( Jeffrey A. Lockwood )

https://www.hcn.org/issues/243/13695

https://www.historynet.com/1874-the-year-of-the-locust/#:~:text=In%201874%20some%20120%20billion,great%20Western%20migration%20of%20Americans.