Food Plant: Helianthemum nummularium (Common Rockrose); Elsewhere: H.apenninum, ovatum; Tuberaria guttata.

Egg: laid on a leaf

Mine: September-May

Notes: The early case is constructed from the excised mine and the larva excavates large greenish yellow blotches. After overwintering the case is lengthened up to three times, with the old case being drawn into a newly mined leaf, which then overlaps the former. The upper surface of the host is hairy and dark this may be seen in the constructed case (as shown), where one side may be darker and hairier than the other. The final case is large, 10-15mm long, being bivalved with mo of 45 degrees. It is found chiefly on chalk and limestone, mostly in rocky situations where the foodplant overhangs ledges. Habitat where larval cases found on Helianthemum growing on a steep south-facing slope with lots of bare ground and crumbling ledges.

Data: 07.vi.2020, Somerset, VC6

Image:© Will Langdon