An external stem mine on Gnaphalium
sylvaticum (Spencer, 1972b:
27). In the latter a single larva moves from leaf to leaf, each
leaf with 2-4 broad diverging tracks extending rarely more than
two-thirds of the length of the leaf from the petiole into the leaf
lamina; frass concentrated in the petiolar part of the mine. Pupation
in mine (Spencer, 1972b:
in the leaf base of the lower leaves, often close to the midrib.
From the leaf base corridors radiate into the leaf disk. Primary
feeding lines in fresh mines well visible. Frass sparingly, granular.
Puaparium in the mine, in the leaf base (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.
Posterior spiracles with approx. 8 bulbs (Spencer,
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).
Hosts in Great Britain & Ireland:
of year - mines: September.
of year - adults: June.
in Great Britain & Ireland: Uncommon. Hereford (Ross) (Spencer, 1972b: 27) and Perth (Fealar) (Bland,
NBN Grid Map:
elsewhere: Germany (Spencer,
1990) and Lithuania (Martinez in Fauna Europaea).
NBN Interactive Grid Maps of known host species:
British and Irish Parasitoids in Britain and elsewhere: Currently unknown.