Fungi classification

Fungi with sporophores (fruiting bodies) large enough to be readily visible will usually belong to one of two main groups. The Basidiomycetes or the Ascomycetes. The main difference between these two groups is in the way in which they produce their microscopic spores.

In the Basidiomycetes, the spores are produced externally, on the end of specialised cells called basidia.

In Ascomycetes, spores are produced internally, inside a sac called an ascus.

Asci and basidia are both microscopic structures.

Basidiomycetes

Ascomycetes

Fungi with spores produced externally, on specialised cells called basidia.

Typically, there are 4 spores per basidium, although this varies from 1 to many, depending on the species.

wpe1F.jpg (2964 bytes)

Fungi with spores produced inside a sac called an ascus.

Each ascus usually contains 8 spores (sometimes 4, depending on the species).

Within the Basidiomycetes, there are three main groups. These are separated by means of differences in the basidia and spores and how these are arranged on the fruiting body.

Gill Fungi (Order Agaricales and Russulales) Boletes (Order Boletales) Polypores, Chanterelles, Coral Fungi, Crust Fungi, Fan Fungi and Toothed Fungi (Order Aphyllophorales)	Stinkhorns (Order Phallales) Puffballs and Earthstars (Order Lycoperdales and Tulostomatales) Earthballs (Order Sclerodermatales) Bird's Nest Fungi (Order Nidulariales)	Jelly Fungi (Order Tremellales)
The basidia develop in layers, called a hymenium, lining gills, tubes, teeth or folds on the fruiting bodies.	Basidia are enclosed inside the fruiting body.	Basidia in a hymenium or layer on the outer surface of the fruiting bodies.

Asymmetrical spores, which are shot off simple basidia.	Symmetrical spores, not shot off the basidia.	The basidia are divided internally - there are various different forms.

Holobasidiomycetes	Gasteromycetes	Heterobasidiomycetes