Plant Parasites of Europe

leafminers, galls and fungi


Secale rye

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

Dichotomous table for leafminers

1a at the start of the mine (not infrequently within a leaf sheath) at the outside an egg shell; larva: mandible with 1 tooth: Hydrellia griseola

1b no egg shell visible; mandible with 2 or more teeth => 2

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

2a larva: cephalic skeleton of Agromyzinae-type; pupation usually outside the mine => 3 *

2b cephalic skeleton of Phytomyzinae-type; pupation within or outside the mine => 12

3a larva: ventrally, behind the mandibles, a field with minute spiny warts => 4

3b no such field => 9

4a larva: abdominal segment 8 dorsally spinulose over its entire width: Agromyza nigrociliata

4b abdominal segment 8 dorsally spinolose only at the anterior and posterior margin => 5

5a larva: rear end of cut off obliquely; larvae mostly communal; mine greenish => 6

5b cut off at right angle; larva usually solitary; mine whitish => 8

6a larva: rear spiracula almost touching each other: Agromya megalopsis

6b rear spiracula separated by at least their own diameter => 7

7a mines in July (1 generation): Agromyza nigrella

7b mines in June and August (2 generations): Agromyza mobilis

8a larva: mandible with 2 teeth: Agromyza rondensis

8b mandible with 3 teeth: Agromyza ambigua

9a larva: the 3 papillae of the rear spiraculum elongated and sigmoid (not quite certain for A. cinerascens) => 10

9b these papillae normal in length and shape: Agromyza albipennis

10a usually on wild grasses: Agromyza cinerascens

10b usually on cultivated cereals => 11

11a larva: front spiraculum with 8 papillae; puparium blackish in front, brown behind: Agromyza luteitarsis

11b front spiraculum with 11-14 papillae; puparium brown throughout: Agromyza intermittens

12a pupation outside the mine; larva and puparium set with transverse rows of long spinelike papillae: Pseudonapomyza atra

12b puparium in the mine; no such spines => 13

13a puparium: front spiracula penetrate the epidermis => 14

13b puparium not connected with the world outside => 15

14a puparium monochromous orange brown; front spiracula indistinctly bifid: Chromatomyia nigra

14 puparium yellow to orange brown with ventrally a darkened length band; front spiraculum fist-shaped: Chromatomyia fuscula

15a larva: rear spiraculum with 11-16 papillae; puparium in the leaf sheath: Cerodontha denticornis

15b rear spiraculum with 6 papillae at most; puparium in the blade => 16

16a 2-4 larvae in a mine; puparia anchored in the mine with a strand of silk => 17

16b larva solitary; puparium loose in the mine => 18

17a larva: the black warts at the outside of the rear spiracula small, without a ‘root’: Cerodontha incisa

17b these warts large, with deep, black, ‘roots’: Cerodontha pygmaea

18a larva: rear spiraculum with a large, black, finely spinulose wart that almost obscures the tracheal tube under it; puparium: rear spiraculum, seen form above, in the form af a U: Cerodontha superciliosa

18b rear spiraculum with a smaller wart that does not cover the tracheal tube: rear spraculum in the form af a V: Cerodontha lateralis

* See also the key to grass-inhabiting Agromyza larvae.

Not included in the key: Coleophora onopordiella; Ochsenheimeria capella, taurella, urella, vaccuella.

Tables for all parasites per species

Last modified 12.iv.2020