Larva mining the stem. Pupation external.
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.
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; posterior spiracles each with an irregular ellipse of 9-14
minute round bulbs.
Hosts in Great Britain & Ireland:
of year - mines: Currently unknown.
of year - adults: Single generation.
in Great Britain & Ireland: Uncommon. Hertfordshire (Barnet) (Spencer, 1972b: 59) and Warwickshire (Combrook) (Robbins,
NBN Grid Map:
Distribution elsewhere: Widespread in continental Europe including Andorra, Estonia, Germany,
Latvia, Lithuania, The Netherlands (Martinez in Fauna Europaea).
recorded in North America (Spencer,
NBN Interactive Grid Maps of known host species:
British and Irish Parasitoids in Britain and elsewhere: Currently unknown.