Bird's nest fungi (Nidulariales: Nidulariaceae) in Baltic and Dominican amber

•A fossil bird's nest fungus is described in Baltic amber.•A fossil bird's nest fungus is described in Dominican amber.•A comparison of extinct and extant characters is presented.

Nidula baltica sp. nov. and Cyathus dominicanus sp. nov. are described from Cenozoic Baltic and Dominican amber. These are the first fossil members of the Family Nidulariaceae and show that the basic characteristics of this group were already established some 40–50 million years ago.