Food Plant: Thymus species

Egg: laid on the leaf

Mine: September-May

Notes: In the autumn the leaf is excised to form the intial case with feeing resuming in the spring. Mined leaves turn brown and tend to drop off the plant, making the presence of this species hard to detect. The leaf is hollowed as the larva feeds, the petiole severed and the leaf opened out and incorporated onto the dorsal surface of the case. A characteristic 'V'shape is formed as each successive leaf is added to the case. The final case is 7-8 mm long, being dark brown and gently curved. Found in dry grassland, mainly in south-east England. A larval case in the field feeding on Thymus sp. These can be difficult to locate, but with practice the feeding damage is detectable on leaves of the foodplant and cases can be found at relatively high densities (at this site most Thyme-covered anthills had at least one larva on).

Data: 22.x.2023, Aston Rowant NR, Oxfordshire, VC23

Image:© Will Langdon