A subdivision containing the most advanced fungi of the *Eumycota
, which are characterized by the production of *basidia
. The mycelium, which may be uninucleate or di-karyotic, is typically divided by inflated septa with a central pore (see dolipore septum). In dikaryotic mycelia, characteristic *clamp connections
are seen. The Basidiomycotina contains over 12 000 species in some 900 genera and is divided into the three classes *Teliomycetes
, and *Gasteromycetes
. In some classifications these fungi are grouped in the class Basidio-mycetes, which is then divided into the subclasses Heterobasidiomycetidae, in which the basidium is deeply divided or septate (e.g. rusts and smuts), and Homobasidiomycetidae, in which the basidium is a single large cell.