Ciboria amentacea, commonly known as the catkin cup, is a species of ascomycete fungus in the family Sclerotiniaceae.

It is widespread in Europe and North America, where it grows on catkins of willow and alder.

[2] The species was first described by Giovanni Battista Balbis in 1804 as Peziza amentacea.

Karl Wilhelm Gottlieb Leopold Fuckel transferred it to Ciboria in 1870.

This Ascomycota-related article is a stub.