Neochetina bruchi (Chevroned Waterhyacinth Weevil) is herbivorous on the freshwater plant Water Hyacinth (Eichornia crassipes), It is native to South America. After research on its specificity, it and N. eichorniae (Mottled Waterhyacinth Weevil) were released in 1972-1974 in Florida for biocontrol of the troublesome plant. In subsequent years, these insects were released in Alabama, Mississippi, Louisiana, Texas, and the Sacramento-San Joaquin Delta in California in 1981-1982 (Army Corps of Engineers 1999). These weevils have also been released in Mexico, India, China, Africa, Australia, and other countries where Water Hyacinth causes problems in waterways. Altogether, N. bruchi has been introduced in 30 countries and become established in 23, as of 2000. In the San Francisco Delta, only 1% pf surveyed plants had weevils, all N. bruchi. The weevils feed on the exterior of the leaves causing scars and reducing photosynthesis. However, the weevil population in the Delta was too small to reduce the Water Hyacinth biomass. In other locations, such as Florida and Louisiana, the weevils have reduced the Water Hyacinth biomass enough to reduce the need for herbicides or mechanical control. The biocontrol program is regarded as a qualified success (Shelton 2024). https://biocontrol.entomology.cornell.edu/weedfeed/Neochetina.php