Horse flies, also known as deer flies or clegs, are haematophagous flies that feed on blood of mammals, bird and even reptiles.  They have a very sore bite and if you’ve ever been bitten by one, you know all about it.  The females are the ones that bite because they need protein to develop their eggs.  They spread diseases including bacterial, viral and protozoan pathogens.  In order to know what species of horse flies are spreading particular pathogens, we need to be able to identify the species correctly. 

This is very challenging in the horse flies in southern Africa because the most complete identification keys for horse flies were published in the 1950’s.  Since then new species have been discovered and new technologies like DNA sequencing have been developed.

Dr Williams, from the Natural Science Department is working on a project with Dr Loki Snyman from the Durban Natural Science Museum to provide updated diagnoses of horse flies commonly found in South Africa and to provide good quality photos of the species for easier identification.

This requires field work to collect specimens and sequencing of the DNA to do phylogenetic analyses to determine how the different species are related to each other.  This will provide valuable information for future studies on the pathogens the species may transmit.