Dichotomous table for gallers on Koeleria
by Hans Roskam
1a On vegetative plant parts => 2
1b Ovaries transformed into a purple-violet gall up to 3 mm long and 1 mm thick gall. K. glauca, pyramidata: Anguina agrostis
2a Locally restricted or expanded malformations on culms and leaves => 3
2b Complete plant disfigured. Shoots of undeveloped plants stunted and ± spongy, swollen. Leaves ± stunted, partially disfigured. K. pyramidata: Ditylenchus dipsaci
3a Only on leaves => 7
3b Only on culms or on their tips => 4
4a Locally restricted galls on the internodes => 5
4b Shoot axis markedly shortened. Development of leaves ± stunted, accumulated into a loose tuft, the outer ones shorter than the inner ones. K. glauca: Unidentified chloropid fly
5a Galls on higher internodes => 6
5b Long spindle-shaped swelling at the base of the culm. Containing a single larva. K. glauca, pyramidata: Tetramesa schlechtendali
6a Sharply shouldered swelling, up to 12 mm long and 4 mm thick. K. pyramidata: Tetramesa sp.
6b Weak swelling, hardly protruding, 1–2 cm above the upper node. K. glauca, pyramidata: Tetramesa sp.
7a Leaf blades, occasionally also the sheaths, with elongated, parallel narrow bulges, at first grey translucent, then with dusting of spores. K. pyramidata: Tilletia sterilis
7b Similar sori. Spore mass black. Spores irregular globular to rotund oval, 10–15 x 8–11 µm. Wall densely covered with short, blunt warts. K. glauca, pyramidata: Ustilago striiformis