Plant Parasites of Europe

leafminers, galls and fungi


Taraxacum dandelion

(For a dichotomous table for galls on Taraxacum by Hans Roskam click here)

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 broad, almost blotchy corridor with secondary feeding lines: Trypeta immaculata

2b no secondary feeding lines apparent => 3

3a blotch < 1 cm, lower-surface, usually several in a leaf; a red wart from above: Cystiphora taraxaci

3b mine different (longer, larger, not like a red wart) => 4

4a mine associated with the midrib => 5

4b mine independent of the midrib => 10

5a larva in the midrib, that is galled and swollen (a gall, rather than a mine): Phytomyza wahlgreni

5b midrib not galled => 6

6a a pinnately branched corridor, the main axis overlying the midrib; pupation outside the mine; frass in fresh mines well visible, in strings; larva: cephalic skeleton of the Phytomyzinae-type: Liriomyza strigata

6b larva lives in the midrib, making from there short excursions into the lamina; these corridors almost without frass; puparium, and most of the frass, in the very base of the hollow midrib; larva: cephalic skeleton of the Agromyzinae-type: Ophiomyia-soorten** => 7

7a full grown (3rd instar) larva: mandible with 1 tooth (beware: they alternate): Ophiomyia pinguis

7b mandible with 2 teeth => 8

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

8b rear spiraculum with ≥10 papillae => 9

9a larva: front spiraculum erect, spine-like, wth ca. 14 papillae: Ophiomyia pulicaria

9b front spiraculum broad, bent, with ca. 7 papillae: Ophiomyia beckeri

10a more or less a blotch: Liriomyza taraxaci

10b more or less a corridor => 11

11a puparium in the mine, in a, usually lower-surface, pupal chamber; corridor not unusually long => 12

11b pupation outside the mine; mine with an unusually long under-surface corridor => 13

12a species of cultivated situations: Chromatomyia cf. syngenesiae

12b species of undisturbed habitats: Chromatomyia farfarella

13a sides of of the upper-surface part of the corridor very irregularly eaten out; larva with a frontal appendage; rear spiraculum with ca. 30 papillae: Phytomyza marginella

13b sides of the upper-surface part of the corridor fairly smooth; no frontal appendage; rear spiraculum with ca. 20 papillae: Phytomyza taraxaci

**In several European countries O. nasuta has been recorded. The larva of this species is not known; the biology, as far as known, seems similar to the other Ophiomyia‘s that are keyed out here.

Not included in the key: Liriomyza trifolii; Ophiomyia maura.

Tables for all parasites per species

Last modified 3.x.2021