NEW PARISH RECORDS FOR CULICOIDES INSIGNIS (DIPTERA: CERATOPOGONIDAE) IN LOUISIANA, USA.

ABSTRACT Culicoides insignis (Diptera: Ceratopogonidae) is an important vector of bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) that affect ruminants. This species is considered neotropical, and is distributed throughout much of South America, Central America, and the Caribbean. In the United States, C. insignis is mainly found in Florida; however, recent studies reported this species from Georgia, Alabama, Mississippi, and Louisiana, suggesting a northwestern range expansion of C. insignis in the southeastern USA. In Louisiana, C. insignis was reported from the northcentral region (Jackson-Bienville-Lincoln parishes) in 2018 based on a one trap-night collection of the species in August 2013, but was not found in the south. Here, we report multiple light-trap collections of C. insignis from East Feliciana parish in southeastern Louisiana from 2022 to 2023, providing new parish records for the species in Louisiana, demonstrating its likely establishment in the state, and confirming the northwestern range expansion of C. insignis in the southeastern USA. However, the role of C. insignis in the transmission of BTV/EHDV in Louisiana is currently unknown and should be examined in further studies.