Thecaphora trailii Cooke 1883

In Great Britain and/or Ireland:
Foodplant / pathogen
embedded sorus of Thecaphora trailii infects and damages capitulum of Cirsium heterophyllum
Remarks: season: 7-8

Foodplant / pathogen
embedded sorus of Thecaphora trailii infects and damages capitulum of Cirsium dissectum
Remarks: season: 7-8

Thecaphora trailii Cooke, Grevillea 11 : 155. 1883
Thecaphora Cirsii Eoud. Bull. Soc. Myc. Fr. 3 : 149. 1887. (Type from France, on Cirsium anghcum . )
Schizonella subtrijida EUis & Ev. (N. Am. Fungi 2266 ; hyponym. 1889) Jour. Myc. 6 : 119. 1891.
(Type from Colorado, on Cirsium ochrocentrum.) Poikilosporium Trailii Vesterg. Micr. Rar. Sel. 452. 1902.
Sori apparently rather indefinite in the flower-heads causing more or less abortion and distortion, at maturity shedding out reddish or purplish -brown dusty spore-mass; sporeballs chiefly subspherical, composed of 2-4 or rarely 5 or 6 spores, very often separating at maturity, about 20-30^ in diameter ; spores reddish-brown, usually hemispherical or threesided or occasionally even more irregular, with contiguous sides fiat and smooth, the free surface rounded and provided with more or less evident reticulations that show at circumference as rather prominent verruculations, chiefly 12-18 // in length.
On Carduaceae :
Carduus leiocephalus/' Uta.'h.^ ,
Carduus ochrocenlrus (emeus ochrocenirus) , Colorado. Type locality : Scotland, on Carduus heterophyllus. Distribution : Utah and Colorado ; also in Europe.