First Records ofCulicoides sonorensis(Diptera: Ceratopogonidae), a Known Vector of Bluetongue Virus, in Southern Ontario

Abstract

Ceratopogonidae (Diptera) were collected on sheep farms in southern Ontario to establish whether Culicoides spp. pose a threat to the livestock industry. Specimens were collected in modified CO2-baited Centers for Disease Control and Prevention light traps, returned to the laboratory, freeze-killed, and identified to species under a microscope. In addition to Culicoides variipennis (Coquillet), we found that Culicoides sonorensis Wirth & Jones occurred on a number of farms over a 2-yr period. These records represent a significant departure from C. sonorensis' previously known geographical distribution. We present spatial and temporal distribution data for both species, with an emphasis on C. sonorensis. DNA sequence information is presented so that researchers lacking the necessary taxonomic skills can determine whether C. sonorensis is present in their collections. To differentiate C. sonorensis from C. variipennis, taxonomically reliable and informative traits were found in EF1α and, to a lesser extent, in ITS1, whereas the universal barcode region of cytochrome oxidase subunit 1 (CO1) was unsuitable.

Culicoides species community composition and infection status with parasites in an urban environment of east central Texas, USA

“…Like many studies, our molecular analysis grouped C. variipennis and C. sonorensis into a single clade. Morphologically these two species are distinguishable [48], but the molecular analysis using the cox 1 marker groups them in a single clade (Shults PT, unpublished data; [49]). Culicoides sonorensis is a known vector of BTV, EHDV and Main Drain virus [50–54].…”

Ecological Dynamics Impacting Bluetongue Virus Transmission in North America

“…C. sonorensis has also been recorded in parts of Canada, and BTV has periodically and transiently incurred in the Okanagan Valley, British Columbia, though these outbreaks appeared to be seasonal introductions without evidence of overwintering (87,88). More recently, C. sonorensis was identified in Ontario on multiple farms during consecutive years (2013-14), suggesting established, overwintering populations (79).…”

“…More recently, C. sonorensis was identified in Ontario on multiple farms during consecutive years (2013-14), suggesting established, overwintering populations (79). The discovery of C. sonorensis in Ontario was quickly followed in 2015 by the first recorded case of BTV in Canada outside of the Okanagan Valley, in an animal near where midges were collected (88). Although Canada was previously thought to be unable to support persistent C. sonorensis populations, the discovery of both virus and vector in Ontario suggests that a changing climate may be allowing a northward expansion of the disease.…”

Laboratory studies on the oviposition stimuli of Culicoides stellifer (Diptera: Ceratopogonidae), a suspected vector of Orbiviruses in the United States

“…In the USA, C. sonorensis has been known to occur primarily through the western states and scattered/rare through the east [ 2 , 8 – 10 ]. However, recent findings of this species in southern Ontario, Canada suggest that C. sonorensis may have undergone a major range expansion towards the northeast [ 11 ], or is poorly documented in some parts of its range. The distribution of C. insignis in the USA is primarily limited to Florida and neighboring states; however, recent reports suggest a northward range expansion of this species as well [ 10 ].…”