Abstract
Culicoides
biting midges (Diptera: Ceratopogonidae) are vectors responsible for the transmission of several viruses of veterinary importance. Previous screens of
Culicoides
have described the presence of the endosymbiont
Candidatus
Cardinium hertigii (Bacteroidetes). However, any impacts of this microbe on vectorial capacity, akin to those conferred by
Wolbachia
in mosquitoes, are yet to be uncovered and await a suitable system to study
Cardinium
‐midge interactions. To identify potential candidate species to investigate these interactions, accurate knowledge of the distribution of the endosymbiont within
Culicoides
populations is needed. We used conventional and nested PCR assays to screen
Cardinium
infection in 337 individuals of 25
Culicoides
species from both Palearctic and Afrotropical regions. Infections were observed in several vector species including
C. imicola
and the Pulicaris complex (
C. pulicaris
,
C. bysta
,
C. newsteadi
and
C. punctatus
) with varying prevalence. Phylogenetic analysis based on the Gyrase B gene grouped all new isolates within ‘group C’ of the genus, a clade that has to date been exclusively described in
Culicoides
. Through a comparison of our results with previous screens, we suggest
C. imicola
and
C. sonorensis
represent good candidates for onward study of
Cardinium‐
midge interactions.