Mine beginning on lower surface but main section on upper surface,
brownish; mine long, linear. Pupation in mine at base of leaf (Spencer, 1972b: 95).
elongated, corridor-like blotch, beginning at the lower surface
but later becoming upper-surface. Frass in numerous small grains,
not more than 2 mm apart. Pupation within the mine, generally near
the base of the leaf (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 larvae lie on their sides within the mine and use their pick-like mouthparts to feed on plant tissue.
Larva and puparium are described by Hering (1924b), de Meijere (1926a), and Griffiths (1980a). Posterior spiracles with 18-25 small globular bulbs (Bladmineerders van Europa).
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).
Yellowish; posterior spiracles each having two distinct arms and
a total of some 20 bulbs (Spencer,
Hosts in Great Britain & Ireland:
of year - mines: September-April, hibernating in the mine (Bladmineerders van Europa).
of year - adults: Currently unknown.
in Great Britain & Ireland: Local. Oxford (Oxford) (Spencer, 1972b: 95). (NBN
recorded in the Republic of Ireland (Martinez in Fauna Europaea).
Distribution elsewhere: Widespread in continental Europe from England to Poland including
southern Finland (Spencer, 1990:
345), Sweden (Spencer, 1976:
443), The Netherlands (Bladmineerders van Europa), Germany (Spencer,
1976: 574), Austria, Belgium, Corsica, Czech Republic, Denmark,
French mainland, Italian mainland, Lithuania, Norwegian mainland
and Poland (Martinez in Fauna Europaea).
NBN Atlas links to known host species:
British and Irish Parasitoids in Britain and elsewhere: