Bite-sized diversity: Culicoides species in Arkansas

Culicoides biting midges are important vectors of bluetongue (BTV) and epizootic hemorrhagic disease (EHDV) viruses, which infect wild and domestic ruminants. The majority of Culicoides research in the US has been done in Florida and California, but there is little data on the species diversity in the mid-south/midwest. In particular, there has been no work done on Culicoides species diversity and distribution in Arkansas. To catalog the diversity of Culicoides across Arkansas, we are conducting a three-year statewide survey, targeting all six ecoregions. In 2022 (Year 1), trapping was conducted at two sites each in the Ozark Mountains and Arkansas River Valley regions. Three CDC UV-LED traps were set nightly at each of the sites for 5 nights in May, July, and August/September. Preliminary data from these collections show that Culicoides are abundant in Arkansas, including species such as C. biguttatus, C. haematopotus, C. stellifer, and C. arboricola. Engorged females will be subjected to blood meal analysis to determine potential host associations, and parous females will be tested for BTV and EHDV, which will reveal putative vector species in the southeast. This study is continuous and will conclude after the summer 2024 field season. 2023 collections are planned for the Ouachita Mountains and Coastal Plain regions. This study will be the first comprehensive report on Culicoides species diversity in Arkansas, and will generate important data on midge phenology, habitat and host use, and putative vector species.