Chromatomyia horticola

The larvae of the fly Chromatomyia horticola mine the leaves of various plants, including Purple Toadflax, creating an upper-surface (sometimes lowersurface also) corridor. Frass appears in isolated grains. Pupation takes place within the mine, usually in a lower-surface, puparial chamber.

See the National Agromyzidae Recording Scheme webpage for this species for further details of puparium and adult insect.

The leafmine is identical to that of Chromatomyia syngenesiae and the two species can only be separated by rearing the larvae and if a male, examination of the genitalia.

ref.: Warrington, B.P. (2023).  Chromatomyia horticola. Accessed at https://agromyzidae.co.uk/species/agromyzidae/phytomyzinae/chromatomyia/chromatomyia-horticola/ on 13/12/2023)

Leafmine Adult

This species can only be identified by examination of the male genitalia. If this is not possible, the leafmine should be recorded as Chromatomyia horticola/syngenesiae agg.

Chromatomyia horticola mines a wide range of plants so can be found in many different habitats.

Click on the 'further details' link in the 'Description' section above.  Then click on the Phenology tab which will provide phenology details for both adult and larval stages.

Leafmines can be found in most months of the year, particularly between April and September.

Widespread and fairly frequent in Britain.

Fairly frequent in Leicestershire and Rutland.