Sympatry in theCulicoides variipennisComplex (Diptera: Ceratopogonidae): a Taxonomic Reassessment

Abstract

We report sympatry among larval populations of the Culicoides variipennis complex in widespread and diverse aquatic habitats throughout the United States. Six sites in California, Nevada, New Mexico, and Texas were co-inhabited by C. v. occidentalis and C. v. sonorensis, whereas 8 sites in Florida, Georgia, Louisiana, Maryland, and Texas were co-occupied by C. v. sonorensis and C. v. variipennis. No intermediate forms were identified either electrophoretically or morphologically in adults reared from field-collected larvae and pupae. The absence of intergrades in zones of sympatry represents sufficient evidence to confirm species status for Culicoides variipennis (Coquillett) and Culicoides occidentalis Wirth & Jones, and to elevate Culicoides sonorensis to species rank (NEW STATUS). Culicoides v. albertensis Wirth & Jones is a synonym of C. sonorensis (NEW SYNONYMY); C. v. australis Wirth & Jones also is confirmed as a synonym of C. sonorensis. We also demonstrated a correlation between population taxonomic status as determined by electrophoresis and adult morphology.

Apparent Increase of Reported Hemorrhagic Disease in the Midwestern and Northeastern Usa

“…Both viruses are transmitted by hematophagous midges of the genus Culicoides, and for BTV, its geographic range is determined by the distribution of competent Culicoides species and environmental conditions affecting vectorial capacity and virogenesis in these vectors (Mullens et al 2004;Schmidtmann et al 2011). In North America, competent vectors for BTV include Culicoides sonorensis (Holbrook et al 2000) and Culicoides insignis (Tanya et al 1992), but a potential for additional Culicoides vectors, especially for EHDV, may exist .…”

Occurrence of Genetic Drift and Founder Effect during Quasispecies Evolution of the VP2 and NS3/NS3A Genes of Bluetongue Virus upon Passage between Sheep, Cattle, and Culicoides sonorensis

“…The vectors of BTV are species of hematophagous midges in the genus Culicoides, and BTV infection occurs throughout tropical and temperate regions of the world (22). Culicoides sonorensis (formerly Culicoides variipennis) is the principal vector of BTV in North America (28,54). Female Culicoides insects become persistently infected with BTV and can transmit the virus to susceptible ruminants after an extrinsic incubation period (EIP) of 10 to 14 days (20,36,41).…”

Molecular detection of bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) in captured Culicoides spp. in the northeastern regions of Mexico

“…The presence of Culicoides midges has been reported in Mexico since 1948 (Macfie, 1948). Apparently, these types of biting midges are widely dispersed in USA and Latin America (Mullens and Dada, 1992;Holbrook et al, 2000;Lager, 2004). It has been reported that C. varipennis var.…”