Taphrina caerulescens (Desmazières & Montagne) Tulasne, 1866
on Quercus

Quercus rubra, Belgium, prov. Antwerp, Balen, Griesbroek, Groot Netewoud © Carina Van Steenwinkel

detail, underside

Quercus rubra, Belgium, prov. Namur, Chimay, Forge-Jean-Petit © Stéphane Claerebout

same leaf, underside

more heavily infected leaf

underside

Quercus rubra, Belgium, prov. Limburg, Beverlo, Vallei van de Grote Beek © Carina Van Steenwinkel

ascus (congo red staining)

two asci with numerous conidia
Quercus rubra seedling, Veeenendaal, Kwintelooijen © Ben van As
same leaf, underside, detail
gall
weakly thickened or blistered leaf spots, protruding at the upper side, generally less than a cm in size. Asci hypophyllous without a basal cell, anchored with rhizoid-like extensions to the epidermis, containing numerous conidia (spores that have sprouted). In the next stage of the life cycle they live as yeasts on the leaf surface.
host plants
Fagaceae, monophagous
Quercus cerris, coccifera, frainetto, hartwissiana, lusitanica, petraea, pubescens, robur, rubra.
Plus a long row of North American oaks. According to Redfern & Shirley in the UK mainly on Q. rubra.
synonyms
Taphrina alutacea (von Thümen) Saccardo, 1889.
parasiet
Cladosporium taphrinae is an obligate parasite of this species.
references
Bataille (1936a), Brandenburger (1985a: 62), Buhr (1965a), Dauphin & Aniotsbehere (1997a), Dietrich (2013a), Klenke & Scholler (2015a), Melgarejo Nárdiz, García-Jiménez, Jordá Gutiérrez ao (2010a), Mix (1936a, 1949a, 1956a), Redfern & Shirley (2011a), Tomasi (2014a).