Bistorta officinalis, England, Vice County: Derby, VC57 © Malcolm Storey, BioImages

open sori

spores

Bistorta officinalis, Belgium, prov. Liège, Bullange, RN de la Vallée de la Schwalm © Stéphane Claerebout

locally the leaf margin is rolled inwards

gall

1-2 mm large grey pustules along the leaf margin, generally so numerous that they coalesce into a continuous ridge; with the epidermis ruptures a brownish- to blackish-violet mass of spores is released.

host plants

Polygonaceae, narrowly monophagous

Bistorta officinalis.

synonyms

Ustilago marginalis (de Candolle) Léveillé, 1849; Bauhinus marginalis (de Candolle) Denchev, 1997.

references

Almaraz (1998a), Brandenburger (1985a: 86), Dauphin & Aniotsbehere (1997a), Klenke & Scholler (2015a), Kruse (2019a), Redfern & Shirley (2011a), Scholz & Scholz (2013a), Spooner & Legon (2006a), Vánky (1994a).