Sepsis

This genus of small flies (2-4 mm) are ant mimics. The are 24 species in the genus and whilst the species can be determined with a good key it is almost impossible to identify them without microscopic examination of the specimen. The genus is generally easy to recognise however by the dark spots near the end of each wing (in British species, there are European species such as S. lateralis which lack these spots).

If you wish to take your determination beyond genus to species you will need a good quality image of the spines along the underside of the front femora for males. Females need their dusting patterns and abdominal bristles to be checked under a microscope if you wish to reach a species determination.

These flies is can be seen visiting flowers on order to obtain a carbohydrate meal, but are most often associated with animal dung, particularly that of cows and horses. Often groups of these flies 'dance' on a leaf, waving wings and legs.

Can be seen most months of the year.

Common and widespread in Britain.

Common in Leicestershire and Rutland