Abstract
Culicoides (Diptera, Ceratopogonidae) are small biting midges and are known as vectors for many arboviruses, including bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV). Tengchong County of Yunnan Province, China, which borders Myanmar, has many private farms with goats, sheep, and cattle. To estimate the risk of Culicoides-borne viral diseases such as bluetongue (BT) and epizootic hemorrhagic disease (EHD) in this area, an investigation of the diversity and abundance of Culicoides in Tengchong between May 2024 and April 2025 was performed. As a result, 70 collections totaling approximately 93,000 Culicoides were carried out at five farms (cattle + Asian buffaloes, goats, and sheep, respectively). Nineteen species were identified, and eight potential cryptic species were found. A total of 13 cox1 sequences and 4 28S sequences for 13 specimens were generated. The most dominant species were Obsoletus (44.1%), C. homotomus (23.3%), and C. arakawae (12.9%) at the bovine farm; C. tainanus (68.0%), C. orientalis (12.6%), and C. newsteadi (Asia) (6.3%) at the goat farm; and C. tainanus (73.6%), C. fenggangensis (7.3%), and C. sp. nr palpifer (6.3%) at the sheep farm. In this investigation, C. tainanus, Obsoletus, and C. orientalis were the most dominant potential BTV vectors, and the period between July and October may be the main period for epidemics of Culicoides-borne viruses in Tengchong.