Heterobasidiomycetes

Abstract

The concept of the Tremellales, or jelly fungi, as defined by Martin (1952) has been radically revised during the past several decades. Some of the families included by Martin in the Tremellales are now treated as separate orders, e.g., Tulasnellales, Dacrymycetales, and Ceratobasidiales. Many of the taxa included by Martin in the Auriculariaceae are placed in a separate subclass and are almost certainly more closely related to the rusts than to the taxa treated here. Electron microscopy has shown that there are fundamental differences in the spindle apparatus and in the structure of the septal pore resulting in the realization that there are at least two lines of phylogeny in the basidiomycetes, i.e., those with a complex septal pores and those with simple pores. Those taxa with simple pores generally possess disc-like spindle pole bodies; whereas those with complex pores generally possess biglobular spindle pole bodies. This is not to imply, however, that all basidiomycetes fall with ease into one of these categories, as some clearly do not. Thus, there may be a third, or even more, major lines of evolution within the basidiomycetes.