of Agromyza varicornis on Lathyrus latifolius
Image: © Colin Plant (British
long white mine mainly in the winged stem, frequently starting in
leaf (Spencer, 1972b: 42).
mine begins as a narrow under-surface corridor. It usually quickly
becomes upper-surface, and also the following blotch part of the
mine is upper-surface. Here and there in the blotch the larvae also
eats from the palisade parenchyma, giving the mine a mottled aspect
when held against the light, but less strongly than in A.
lathyri . Frass in the initial corridor, if at all visible,
in short threads; very little frass in the blotch. Pupation outside
the mine (Bladmineerders van Europa).
The mine is in the wing of the stem, but often starts in leaf (though not always) (British
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 Hering (1957). Posterior spiracles each with
3 bulbs (Spencer, 1972b:
42 and 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).
Posterior spiracles each with 3 bulbs (Spencer, 1972b: 42).
Hosts in Great Britain & Ireland:
of year - mines: June, August.
of year - adults: Currently unknown.
in Great Britain & Ireland: Widespread in Britain including
London (Hampstead), Isle Of Wight (Luccombe), Cambridge (Cambridge),
Denbighshire (Cefn-y-bedd) (Spencer, 1972b: 42) and Warwickshire (Coventry) (Robbins,
1991: 46). South Lancashire, Surrey, West Gloucestershire (NBN Gateway).
elsewhere: Widespread in continental Europe including Germany
(Bladmineerders van Europa), Italian mainland, Lithuania, Spanish mainland and
Yugoslavia (Martinez in Fauna Europaea).
NBN Interactive Grid Maps of known host species:
British and Irish Parasitoids in Britain and elsewhere: Currently unknown.