Alnus glutinosa, Belgium, prov. Antwerp, Mol, Buitengoor-Meergoor © Carina Van Steenwinkel

detail

underside

Alnus glutinosa, Nieuwendam: cleistothecium

appendage

Alnus glutinosa, Belgium, prov. Antwerp, Balen, Griesbroek © Carina Van Steenwinkel: cleistothecium appendages

cleistothecium with asci

gall

mycelium amphigenous, very thin, often nearly invisible. Conidia solitary, without fibrosin bodies. Cleistothecia small, mainly hypophyllous, with 3-6 asci, containing 6-8spores. Appendages 5-20, 1-1.5 the diameter; stiff, brown at the base, apically several times bifurcating in quick succession.

host plants

Betulaceae, monophagous

Alnus cordata, glutinosa, hirsuta, incana & subsp. rugosa, japonica, maritima, rubra, viridis.

synonyms

Microsphaera penicillata (Wallroth) Saccardo, 1882.

references

Abras, Fassotte, Chandelier & Cavelier (2008a), Brandenburger (1985a: 50), Braun (1995a), Braun & Cook (2015a), Bresinsky (2016a), Ellis & Ellis (1997a), Jage, Kruse, Kummer ao (2013a), Jage, Klenke & Kummer (2010a), Jage, Scholler & Klenke (2010a), Klenke & Scholler (2015a), Kruse (2014a, 2019a), Riegler-Hager (2000b), Scholler & Schubert (1993a), Talgø, Sundheim, Gjærum ao (2010a).