F. de Thuemen, Mycotheca Universalis. Centuria XV. 1473. Fusidium Petasitidis Pass. nov. spec. Hypophyllum, plus minus effusum, albidum, flocculoso-pulverulentum; conidia longitudine varia, oblongo-elliptica vel bacillaria, integra, hyalina. Parma: Gajone ad folia viva Petasitidis officinalis Monch socia Coleosporii Petasitidis Lev. Aug. 1878. leg. Prof. Passerini.