Dichotomous table for gallers on Agrostemma githago
by Hans Roskam
1a On vegetative organs => 2
1b Anthers in rarely disfigured flowers temporarily swollen; later filled with black-violet spores. Microbotryum violaceum
2a Malformations with surface fruiting fungi, at least temporarily => 5
2b Malformations caused by animals => 3
3a Malformations on stems or leaves of ± developed plants => 4
3b Young plants severely stunted; especially the basal parts swollen, spongy. Swellings pale green, undulate at surface. Ditylenchus dipsaci
4a Stem with localised swellings. Unidentified lepidopteran
4b Tuft-like accumulation of basally strongly pubescent leaves. Inducer unknown
4c Stem stunted locally, one or two neighbouring leaves strongly rolled over their tips; close to the froth-covered nymph undulate, deep-green. Philaenus spumarius
5a Leaves on underside with rotund, ring-shaped or sometimes oblong compact crusts of coalescing sori on slightly swollen bulges; at first bearing pale, later on with black-brown telia. Bulges also developing on calyx teeth and stems. Puccinia arenariae
5b Leaves and stems with yellowish, ± swollen spots; diseased leaf blades, and even the corolla, often characteristically curled; sori ± grey frosted when asci are mature. Taphrina githaginis