Key to Danish species of Craterium Trentep.

1 Sporocarps dehiscing by a clearly delimited lid. 2
1' Sporocarps dehiscing irregularly in apical part or indistintly circumscissile. 4
2   (1) Sporocarps with a sharply delimited lid, convex or sunken below margin; always stipitate; sporocarp colour from ± yellowish brown to dark chestnut brown. C. minutum (Leers) Fr. - 3
2' Lid with slightly frayed rim, convex, papillose on the inside. Sporocarps short-stalked or almost sessile; dull orange brown or whitish from granular lime. C. aureonucleatum Nann.-Bremek.
3   (2) Sporocarps pale brownish to dull orange. Stalk not longer than sporotheca hight. Lid mostly clearly convex to flattened; often paler than calyculus. C. minutum (Leers) Fr. var. minutum
3' Sporocarps shiny dark brown all over. Stalk usally as long as calyculus. The lid is sunken below the edge. Capillitium with many small lime-bodies. C. minutum (Leers) Fr. var. brunneum (Nann.-Bremek.) L.G. Krieglst.
4   (1) Sporocarps deep cup-shaped to almost globose. Peridum white from lime granusle, reddish brown at base. C. leucocephalum (Pers. ex J.F. Gmel.) Ditmar - 5
4' Sporocarps globose. Peridium bright yellow or grey to brown. 6
5   (4) Sporocarps cup-shaped to short cylindrical. Dehiscence circumscissile with a ± regular rim. Spores 8-9.5 µm Ø. C. leucocephalum (Pers. ex J.F. Gmel.) Ditmar var. leucocephalum
5' Sporocarps ± globose. Dehiscence irregularly circumscissile with a frayed rim. Spores 9-11 µm Ø. C. leucocephalum (Pers. ex J.F. Gmel.) Ditmar var. scyphoides (Cooke & Balf. f.) G. Lister
6   (4) Sporocarps bright yellow. Spores 8-9.5 µm Ø, with fine warts. C. aureum (Schumach.) Rostaf.
6' Sporcarps grey to brown. Spores 12-17 mm Ø, with blunt spines arranged in a fragmentary net. C. dictyosporum (Rostaf.) Neubert, Nowtny & Baumann