very long mine. Pupation at base of leaf (Spencer, 1972b: 100).
long upper-surface corridor, at the end about 1/3 of the width of
the leaf. The mine usually begins about halfway along the blade
and descends within the leaf sheath. Just before pupation all frass
is deposited in one big mass. Puparium within the mine, where it
also passes the winter (Bladmineerders van Europa).
Larva: The larvae of flies are leg-less maggots without a head capsule (see examples). They never have thoracic or abdominal legs. They do not have chewing mouthparts, although they do have a characteristic cephalo-pharyngeal skeleton (see examples), usually visible internally through the body wall.
The larva is described by de Meijere (1928
and 1937), Dempewolf (2001:
111) and Nowakowski (1973). Anterior spiracles very large, bifid, with 24-30 papillae. Posterior spiracles large as well, with 3 hook-like bulbs. Body yellow.
Puparium: The puparia of flies are formed within the hardened last larval skin or puparium and as a result sheaths enclosing head appendages, wings and legs are not visible externally (see examples).
Brown, rather flat (Spencer, 1972b: 100).
Hosts in Great Britain & Ireland:
of year - mines: Currently unknown.
of year - adults: Currently unknown.
in Great Britain & Ireland: Probably widespread. Surrey
(Godalming) (Spencer, 1972b:
100) and Cambridge, East Sussex and Stafford (NBN
Distribution elsewhere: Widespread in continental Europe including Denmark,
Finland, Norway, Sweden (Spencer,
1976: 209), Germany (Spencer,
1976: 554; Dempewolf, 2001:
111), Bulgaria, Czech Republic, Hungary, Lithuania, Poland and Slovakia
(Martinez in Fauna Europaea).
recorded in Canada (Spencer,
NBN Atlas links to known host species:
British and Irish Parasitoids in Britain and elsewhere: