1a the three papillae of the rear spiracula elongated, sigmoid => 2

1b these papillae neither elongated nor sigmoid => 4

2a (almost) exclusively on wild grasses, especially Dactylis glomerata: cinerascens

2b (almost) on cultivated cereals => 3

3a front spiraculum with 8 papillae: luteitarsis

3b front spiraculum with 11-14 papillae: intermittens

4a rear spiracula sessile, wide apart; only on Phragmites => 5

4b rear spiraculum stalked, more or less close together => 6

5a pupation within the mine; species of almost entire Europe: graminicola

5b pupation external; species from southern Spain: baetica

6a rear spiracula almost touching each other, separated by less than their diameter => 7

6b rear spiracula well separated => 10

7a mandibel with 2 teeth; only on Phragmites => 8

7bmandibel with 4 teeth => 9

8a rear arms of the cephalic skeleton weakly chitinised, yellowish: phragmitidis

8b these arms dark brown or black: hendeli & spenceri

9a front spiraculum with 9 papillae; mainly on cultivated cereals: megalopsis

9b front spiraculum with 12-16 papillae; only on wild grasses (preference for Phalaris): albipennis

10a bands of spines on the segments unusually wide; on abd. 8 the band dorsally occupies the entire width of the segment: nigrociliata

10b bands of spines narrower => 11

11a behind the mandibles ventrally a field with short spines => 12

11b no such field of spinules => 14

12a rear end of the blunt => 13

12b rear end cut off obliquely: mobilis & nigrella

13a mandibel with 2 teeth: rondensis

13b mandibel with 3 teeth: ambigua

14a mandibel with 2 teeth: nigripes

14b mandibel with 3 teeth: lucida