Plant Parasites of Europe

leafminers, galls and fungi

Acalitus rudis

Acalitus rudis (Canestrini, 1890)

on Betula

Acalitus rudis gall on Betula pendula

Betula pendula, Otterlo, de Zanding; upperside of the leaf © Arnold Grosscurt

Acalitus rudis gall on Betula

underside of the leaf

Acalitus rudis gall on Betula pendula

Betula pendula, Koudhoorn: the hairs of the erineum are “mushroom shaped”.

Acalitus rudis: gall hairs

Betula pendula, Bergen NH, Uilenvanger: gall hairs under the microscope


Betulaceae, monophagous

Betula humilis, nana, pendula, pubescens, pumila.


Aceria, Eriophyes, rudis. The illustration and description of E. rudis by Houard partly apply to Acalitus calycophthirus.


On galls of this type lives a specialised mildew, Podosphaera erineophila. The causer of the gall itself remains unspecified in the literature (“Erineum betulinum”), but is is worthwile to be alerted on it!


Béguinot (2006a, 2007b), Bellmann (2012a), Buhr (1964b), Cogolludo (1921a), Coulianos & Holmåsen (1991a), Dauphin & Aniotsbehere (1997a), Farkas (1965a), Fjelddalen (1995a), Hellrigl (2003a, 2004b), Houard (1908a), Lambinon, Carbonnelle & Claerebout (2015a), Lambinon Schneider & Feitz (2012a), Nalepa (1919a), Redfern & Shirley (2011a), Ripka (2007a), Roivainen (1951a), Roskam (2009a), Skoracka, Lewandowski & Boczek (2005a), Sylvén (1960a), Tomasi (2014a), Vaněčková-Skuhravá (1996a), Wahlgren (1963b), Weidner (1954a).

Last modified 27.ii.2020