Reproductive endosymbionts in Dolichopodidae

Vertically transmitted reproductive parasites are both extraordinarily widespread and diverse in their effects on their invertebrate hosts. In addition to causing skewed population sex ratios via male-killing or feminization, such bacteria can further cause cytoplasmic incompatibility or parthenogenesis.

Previous surveys show that the microbes Wolbachia and Spiroplasma are common in some dipteran families, e.g. Drosophilidae or Scathophagidae, and are known to be heritable symbionts and affect reproduction in the Diptera. In stark contrasr, information on Rickettsia infections and detailed surveys targeting other Dipteran families are lacking. For instance, the superfamily Empidoidea contains numerous species, which have been the targets of intense research concerning reproductive traits involved in sexual selection. However, little is known about endosymbiont infections in most of these species.

In this study, we survey more than 300 samples of approx. 250 species of flies belonging to the Dolichopodidae, Empididae and Hybotidae, for the presence of the endosymbionts Wolbachia, Spiroplasma, and Rickettsia. 151 of the species (i.e. ca. 61%) screened here, including species from key genera such as Dolichopus, Poecilobothrus or Empis, harboured one or more symbionts. Reproductive parasites are thus also common in the Empidoidae, yet effects on hosts remain unclear. Potential endosymbiont-host interactions in this group would hence be worthy of further investigation.

Martin et al. 2013 Infections, genetics and evolution 

Image credit: Metcalf & Bordenstein 2012