Mentha mint

Dichotomous table for leafminers

1a fleck mine; larva mines from a blackish brown case: Coleophora albitarsella

1b fine gallery, descending, via the petiole, down the stem: Glaucolepis saturejae

1c gallery or blotch => 2

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

2a full depth blotch; larva with chitinised head => 3

2b mine upper- or lower-surface; gallery or blotch; larva a maggot => 9

3a over the oviposition site, at the leaf margin, a shining black drop of dried secretion; larva, with a black spot on each segement, pupates in the mine: Trachys scrobiculatus

3b no such drop, larva not so strongly marked; pupation external => 4

4a wrinkled, full depth blotch; the first mine that the larva makes starts with a fine gallery: Stephensia cedronellae

4b mine flat, not initial gallery => 5

5a the larve mines all its life; larva without prolegs: Dibolia occultans

5b only the young larvae mine, later they live between spun leaves; they have prolegs => 6

6a larva with 5 length lines: Scrobipalpa artemisiella

6b larva without, or just one, length line => 7

7a larva: pinacula colourless (the bases of the setae themselves are black) : Cnephasia incertana

7b pinacula black => 8

8a larva: behind/below the anus a chitinous comb: Cnephasia asseclana

8b anal comb absent: Cnephasia stephensiana

9a narrow corridor, abruptly widening into a primary blotch; no secondary feeding lines => 10

9b corridor from start to end; the corridor windings may come close together, forming a secondary blotch, with conspicuous secondary feeding lines => 11

10a frass in the corridor part in a broad green central band, with tiny black granules at either side: Amauromyza labiatarum

10b frass in the entire corridor as neat thread fragments, alternating along the sides: Amauromyza lamii

11a secondary blotch with conspicous secondary feeding lines; mine begins at a brown spot: Phytomyza tetrasticha

11b no secondary blotch, no secondary feeding lines, no brown spot => 12

12a puparium in the mine, its anterior spiracula penetrating the epidermis; frass in discrete grains: Chromatomyia horticola

12b before pupation the mine is vacated through a semicircular exit slit (sometimes pupation occurs precociously, but then the exit slit is made already, and the spiracula do not penetrate); frass partly in strings: Phytomyza petoei

Not included in the key: Dibolia cryptocephala.

mod 2.iii.2018