Carpinus betulus, from González-Fragoso (1925a): cross section through an uredinium

gall

spermogonia and aecia not known. Uredinia hypophyllous, corresponding with yellow spots at the upperside, delimited by the leaf venation; at first covered by the epidermis, then by a peridium that releases the spores through a central pore; spores sparsely spinulate, apex smooth. Telia mostly hypophyllous, small, yellow when fresh; spores formed subepidermally.

host plants

Betulaceae, oligophagous

Carpinus betulus; Corylus avellana; Ostrya virginiana.

references

Bahçecioğlu & Kabaktepe (2012a), Brandenburger (1985a: 55), Chlebicki & Chmiel (2006a), Gäumann (1959a), González-Fragoso (1925a), Huseyin & Selcuk (2004a), Klenke & Scholler (2015a), Kruse, Thiel, Beenken ao (2018d), Poelt & Zwetko (1997a), Schmid-Heckel (1985a), Termorshuizen & Swertz (2011a).