Athalia species
The Athalia species are extremely hard to tell apart. All species, of which some 10 species are present in Britain, are yellowish red and have a variable amount of black markings and light ringed legs. On the web you will find a lot of pictures of one particular species: the Turnip Sawfly, also known as the Coleseed Sawfly (Athalia rosae). With a number of these pictures the identification is doubtful, to say the least. Our animal could be a Turnip Sawfly as well, but we can not be sure at all. The animal was seen flying about in great numbers in April. This would indicate another species, for the Turnip Sawfly appears in May. The Turnip Sawfly regularly becomes a pest in Mustard and Cole, for it is fully specialised in Cole and other Crucifers.