Dichotomous table for gallers on Echium
by Hans Roskam
1a On inflorescences, flowers or fruits => 6
1b On vegetative parts => 2
2a On shoot tips, lateral buds, stems or leaves => 3
2b Complete plant stunted, leaves clustered and like flowers ± etiolated. E. vulgare: Brachycaudus helichrysi
3a On leaves, buds or stems => 4
3b Shoot tip stunted close to ground, transformed into an oblong-egg-shaped blotch with large central chamber, not enclosed by unfolding leaves. E. italicum, vulgare: Cynaeda dentalis
3c Gall on root head. E. vulgare: Pachycerus segnis
4a On leaves or buds => 5
4b Stem locally stunted and swollen, with several rimmed depressions containing a nymph. E. vulgare: Planchonia arabidis
5a Lateral buds transformed into an unopened egg-shaped gall, not dropping in autumn. Contains a single yellow larva. E. arenarium, vulgare: Asphondylia echii
5b Leaf blade with conspicuous, rotund, yellow or reddish pads, ± depressed on upper side, arched on underside or similar, elongated spindle-shaped bulges on venation. E. plantagineum, vulgare: Puccinia recondita f. sp. echii-agropyrina
6a On inflorescences, flowers => 7
6b One of the mericarps enlarged; the remaining ones aborted. Containing a single larva. E. vulgare: ? gall midge, ? gall wasp
7a Expanded parts of inflorescence disfigured => 9
7b Malformations of single or several flowers => 8
8a Corolla unopened, not or hardly surpassing calyx teeth; lower half swollen, thickened, white; upper half acuminate, thickened and reddish. Stamens and ovary thickened. Larvae glossy, lemon-yellow, jumping. E. vulgare: Contarinia echii
8b Flower swollen, unopened, gall rotund-oval. Stamens and pistil aborted. Inner wall lined with mycelium. Containing a single larva. E. arenarium, vulgare: Asphondylia echii
9a Many flowers disfigured, their parts variously leafy, abnormally pubescent. E. vulgare: Aceria echii
9b Inflorescences shortened. Flowers distorted. E. vulgare: Dictyla echii
9b Axis of inflorescence stunted and clustering of flowers of E. vulgare caused by froth-covered nymphs of Philaenus spumarius