Erysiphe hypophylla (Nevodovsky) Braun & Cunnington, 2003
Quercus robur, Nieuwendam: cleistothecium
Quercus robur, Belgium, prov. Antwerp, Mol, Klein Verkallen © Carina Van Steenwinkel
same leaf, underside
mycelium inconspicuous, thin, mainly hypophyllous. Conidia formed sparingly, sometimes missing, solitary, cylindric, with rounded tips, without fibrosin bodies. Cleistothecia mainly hypophyllous, with 4-16 asci that contain 6-8 spores. Generally 10-10 appendages, attached to the equator. They are up to 2 x as long as the diameter, stiff, hyaline, septate, more or less straight; at the tip they are suddenly broadened because they are bifurcating there several times in quick succession.
Quercus frainetto, petraea, pubescens, robur & subsp. pedunculiflora.
Microsphaera hypophylla Nevodovsky, 1952.
The cleistothecia cannot be distinguished from those of E. alphitoides that also lives on oaks. Contrary to that species, the leaves are not disfigured. Like alphitoides a neophyte, that arrived in Europe around the middle of the 20th century.
Braun (1995a), Braun & Cook (2102a), Braun, Cunnington, Brielmaier-Liebetanz, Ale-Agha & Heluta (2003a), Bresinsky (2016a), Dynowska, Fiedorowicz & Kubiak (1999a), Klenke & Scholler (2015a), Kozłowska, Mułenko & Heluta (2015a), Kruse (2014a, 2019a), Leysen (2017a), Ruszkiewicz-Michalska (2006a), Ruszkiewicz-Michalska & Michalski (2005a), Sucharzewska (2009a), Sucharzewska, Dynowska, Kubiak ao (2012b), Talgø, Sundheim, Gjærum ao (2010a).