gallers on Eryngium

1a On leaves or stems => 2

1b On inflorescences or flowers => 5

2a Malformations lacking fructifying fungal sori on surface => 3

2b Leaf veins and -stalks with yellowish, spindle-shaped or elongated sometimes curved bulging swellings bearing aecia. E. campestre, creticum, falcatum, glomeratum, tricuspidatum: Puccinia eryngii

2c Leaves with fawn-coloured raised spots, 1–3 mm across, containing yellow-brown smut spores. E. planum: Entyloma eryngii-plani

3a Malformations on leaf blades => 4

3b Conspicuous swellings, up to 15 mm thick, usually expanded, multi-chambered, on stems and petioles. Inner wall of chamber covered with fungal hyphae. Each chamber containing a red larva. E. amethystinum, campestre, maritimum, tricuspidatum: Lasioptera eryngii

3c Malformation of stem. E. campestre, planum: Inducer unknown

4a Leaf blade reduced, rolled upwards, curled and discoloured. E. campestre, maritimum: Unidentified aphid

4b Leaf blade often with many distinct protruding or indistinct, rotund or angular pustules, 1–3 mm across, at first sometimes violet, soon browned, with many spores inside. E. alpinum, campestre, maritimum, planum: Entyloma eryngii

5a Style of flower thickened, ovary stunted. E. campestre: Unidentified gall midge

5b Centre of (partial) umbel swollen, globular or club-shaped; gall uni-, also multi-chambered, each containing a red larva. E. campestre: Lasioptera carophila