1a large, untidy fleck mine; the opening is a lateral slit: Jordanita subsolana

1b blotch or gallery => 2

1c galls, etc => Tables for all parasites per species

2a gallery => 3

2b blotch => 4

3a frass in discrete grains; puparium in the mine, in a, usually lower-surface, pupal chamber: Chromatomyia cf. syngenesiae

3b frass in long threads; pupation after the mine has been vacated: Phytomyza bipunctata

4a larva a maggot, without head or legs: Amauromyza carlinae

4b larva a caterpillar, with prolegs => 5

4c beetle larva, without prolegs: Sphaeroderma rubidum

5a elongate blotch overlying the midrib; larva mines all its life: “Gnorimoschema ochraceellum“

5b mine not associated with the midrib; older larvae live free => 6

6a mine contains much frass: Tebenna micalis.

6b little frass: Agonopterix ferocella