Taphrina tosquinetii

Taphrina tosquinetii is a fungal plant pathogen that causes large blisters on both surfaces of the leaves of alder.

Taphrina tosquinetii
Scientific classification
Kingdom:	Fungi
Division:	Ascomycota
Class:	Taphrinomycetes
Order:	Taphrinales
Family:	Taphrinaceae
Genus:	Taphrina
Species:	T. tosquinetii
Binomial name
Taphrina tosquinetii (Westendorp) Tulasne, 1866[1]
Synonyms[2]
Ascomyces tosquinetii Westend., 1861 Exoascus tosquinetii (Westend.) Syd. & P. Syd.

Description of the gall

The ascomycete induces a gall that distorts the leaves of alder. The leaves are slightly thickened, brittle and incurved with blister-like growth on both sides, which can increase the size of an infected leaf to twice the normal size. Later the leaf tissue becomes pale and thin with a whitish bloom when the asci develop.^[3][4] Species infected include common alder (Alnus glutinosa), grey alder (Alnus incana) and Alnus x pubescens.^[1]