Platycheirus rosarum is a species of hoverfly found in many parts of Britain and Europe. Like its close relative Platycheirus granditarsus it can be found in marshy meadows and ditches; indeed, the two species can often be found together. The flight time is between May and October though it peaks in abundance in June and July. The most distinctive feature of this fly is the pair of yellowish spots on tergite 2 on an otherwise completely black abdomen.