Assessing genetic lineages of the biological control agent Megamelus scutellaris in its native range
Megamelus scutellaris (Hemiptera: Delphacidae) is a biological control agent for Pontederia crassipes (Pontederiaceae: EPPO A2 List), one of the world’s most invasive aquatic plant species. P. crassipes is native to South America and has been introduced into the EPPO region where it has been observed to cause significant negative impacts including blocking water channels, degrading biological diversity, and providing breeding grounds for mosquitoes. M. scutellaris has previously been utilised as a biological control agent against P. crassipes in the USA and South Africa. M. scutellaris has a wide native range, from the Amazon River basin to the Río de la Plata basin, including Argentina, Uruguay, northern Peru, and southern Brazil. Salinas et al. collected populations of M. scutellaris from different climatic regions in the native range for release in the USA and South Africa. They found that in its native range, M. scutellaris has three main genetic lineages associated with major river basins and ecoregions. Genetic differences within the native range were shown to be strongly associated with climate differences and environmental isolation. Assessing genetic differences at a biogeographical scale can help to inform climatic matching between the native range and recipient regions, which can increase the success of biological control
Sources
Salinas NA, Poveda-Martinez D, Rodriguero MS, Smith MC, Brentassi MA, Sosa AJ (2026) Landscape genomics and evolutionary history of Megamelus scutellaris, a biocontrol agent of the invasive water hyacinth (Pontederia crassipes). Evolutionary Applications 19, e70208. https://doi.org/10.1111/eva.70208