Cnicus Blessed, Holy, Thistle
In the past a considerable number of thistle species were classified in this genus, that presently are attributed to a number of different genera, in particular Cirsium. Presently, the only remaining species, C. benedictus, has been transferred to Centaurea (Euro+Med PlantBase, 2016).
Dichotomous table for leafminers
1a most of the mine overlying the midrib => 2
1b corridor that winds freely through the leaf => 3
1c galls, etc => Tables for all parasites per species
2a mine at either side of the midrib with broad blotch-like expansions; larva very active on disturbance, with feet and chitinised head: Scrobipalpa acuminatella (the occurrence on this host plant is doubted)
2b mine with slender pinnate side branches; larva a sluggish maggot: Liriomyza strigta