Parna tenella

The adult Parna tenella sawfly is 4 to 5 mm. The head, thorax and abdomen are all black or piceous. In the male, the legs and much of the abdomen are reddish-yellow (darker basally). In the female, the tegulae are dark. The hind legs with the trochanters and femora entirely yellow. Parna tenella larvae mine the leaves of Lime, particularly Small-leaved Lime, producing a somewhat inflated full depth blotch, that begins at the leaf margin. The oviposition causes the leaf to roll inwards, covering (and often partly hiding) the mine. There are often several mines in a leaf. Mainly in suckers. Frass pellets up to 2 mm long.

Parna apicalis

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.tenella.htm

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

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