Picris ox-tongue

Incl. Helminthia, Helminthotheca.

Dichotomous table for leafminers

1a mine full depth; larva with chitinised head: Orthochaetes setiger

1b mine upper- or lower-surface; larva a maggot => 2

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

2a mine associated with the midrib => 3

2b mine independent of the midrib => 7

3a larva in the base of the midrib, that is galled and swollen: Phytomyza picridocecis

3b midrib not swollen => 4

4a mine pinnately branched; pupation after the mine has been vacated; frass in strings in the corridor and its side branches; larva: cephalic skeleton of the Phytomyzinae-type: Liriomyza strigata

4b larva lives in the midrib, from where it makes short excursions into the lamina; these corridors almost free of frass, which is accumulated in the base of the hollow midrib; there also the puparium; larva: cephalic skeleton of the Agromyzinae-type => 5

5a larva: rear spiraculum with 8-9 papillae: Ophiomyia cunctata

5b larva: rear spiraculum with > 10 papillae => 6

6a larva: front spiraculum spine-like, erect: Ophiomyia pulicaria

6b llarva: front spiraculum broad, curved: Ophiomyia beckeri

7a puparium in the mine in a, usually lower-surface, pupal chamber: Chromatomyia cf. syngenesiae

7b pupation outside the mine => 8

8a mine starting with an unusually long lower-surface corridor, continued in an upper-surface gallery: Phytomyza marginella

8b short, upper-surface gallery, continued in a blotch: Liriomyza obliqua.

Not included in the key: Liriomyza bryoniae, sonchi, trifolii; Phytomyza cecidonomia; Trypeta immaculata.

mod 26.iv.2019