Dichotomous table for gallers on Centaurium
by Hans Roskam
1a Leaves on underside with many pearl-like small warts, hardly 1 mm long. C. pulchellum: Synchytrium globosum
1b Dull white spots, pustules, even crusts on underside of leaves, largely consisting of a mass of conidia. C. spicatum: Pustula centaurii
1c Plant ± disfigured; flowers greened. C. erythraea: Inducer unknown – ? gall mite
= Galls on Centaurium have been attributed to either the snout beetle Smicronyx reichi or S. funebris