The adult Parna apicalis sawfly is 3.5 to 4 mm. The head, thorax and abdomen are all black or piceous. The tegulae and tibiae and tarsi are marked with yellow. The hind coxa, trochanters and femora are black. Parna apicalis larvae mine the leaves of Lime trees creating a blister mine in contact with the leaf edge but does not cause the leaf to curl as Parna tenella does. Rarely more than one mine per leaf. Mines mainly in the canopy. Frass grains elliptic, about 0.5 mm long.

Parna tenella

Adult leaf mine

Good photographs required including a back-lit image of the mine showing the frass. Please also state the host species.

The mines may be found where the host Lime species occur.

The mines may be found when the host Lime species are in leaf. Adults can be seen in May and June.

Widespread in England and Wales, but rather local in its distribution.

Rarely recorded in Leicestershire and Rutland.

http://www.leafmines.co.uk/html/Hymenoptera/P.apicalis.htm

https://bladmineerders.nl/parasites/animalia/arthropoda/insecta/hymenoptera/symphyta/tenthredinoidea/tenthredinidae/heterarthrinae/parna/parna-apicalis/

https://www.sawflies.org.uk/parna-apicalis/