Leaf-mine: Larvae feeding in stem-leaves. particularly those immediately below
the flower; mine initially linear, later developing into irregular
blotch. Pupation internal (Spencer,
a corridor, later an irregular blotch. Pupation within the mine;
puparium whitish (Bladmineerders van Europa).
The initial mine is a gallery, it later makes a lower surface blotch mine (British
of Chromatomyia blackstoniae on Blackstonia perfoliata
Image: © Brian Pitkin
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).
Whitish (Spencer, 1990: 396).
Spencer (1972b: 95) recorded
Chromatomyia gentianae (as Phytomyza) on Blackstonia
perfoliata and Centaurium
erythrae (as minus). However, he later (Spencer,
1990: 396-7) recognised that specimens on Blackstonia
perfoliata and specimens on Centaurium
erythrae represented two different new species, which he described
blackstoniae and Chromatomyia
Hosts in Great Britain & Ireland:
of year - mines:
August (Spencer, 1990).
of year - adults: Currently unknown.
in Great Britain & Ireland: Gloucestershire (Kilcot) (Spencer,
1990: 396), Oxfordshire (Warburg Reserve) (British
leafminers), Surrey (Boxill) (pers. observation). (NBN
recorded in the Republic of Ireland: Co. Clare (Murrough) (Spencer,
elsewhere: Northern France (Spencer,
NBN Atlas links to known host species:
British and Irish Parasitoids in Britain and elsewhere: Currently unknown.