Dichotomous table for gallers on Aposeris foetida
by Hans Roskam
1a Malformations on the plant surface not occupied by fungi => 2
1b Leaf blade on the underside with round 1 (2) cm large, yellowish to reddish-brown spots with many close and distinctly bordered aecia. Sporulating areas on the veins with slightly cushion-like bulges. Puccinia poae-aposeridis
2a Galls on the leaf blade or on the margin => 3
2b Hyaline callus on the midrib, radiating to lateral veins; venation strongly swollen; leaf blade sometimes ± malformed; centre yellowish discoloured. Spores predominantly in phloem. Protomyces kreuthensis
2c On the leaf blade, in many usually brownish spots, up to 1 mm long, sometimes slightly bulged. Entyloma aposeridis
3a Leaf blade glabrous, margin rolled upwards. Unidentified thrips
3b Leaf blade on the underside with small depressions and corresponding swellings on the upper side; strongly infected leaves sometimes ± twisted and rolled at the margin. Trioza dispar
3c Browning of leaf blade; at high densities rusting may occur. Epitrimerus protrichus