Ascomycota is a
Division/
Phylum of
Fungi, and subkingdom
Dikarya, whose members are commonly known as the
Sac Fungi. Characteristically, when reproducing sexually, they produce nonmotile
spores in a distinctive type of microscopic
cell called an "
ascus" (from
Greek ?s??? (
askos), meaning "sac" or "wineskin"). These spores are called
ascospores. However, some members of the Ascomycota do not reproduce sexually and do not form asci or ascospores. These members are assigned to Ascomycota based upon
morphological and/or
physiological similarities to ascus-bearing taxa, and in particular by
phylogenetic comparisons of
DNA sequences.
[2][3]This monophyletic grouping is an extremely significant and successful group of organisms. Familiar examples of sac fungi include morels, truffles, brewer's yeast and baker's yeast, Dead Man's Fingers, cup fungi, and the majority of lichens (loosely termed "ascolichens") such as Cladonia. Many plant-pathogenic fungi belong to the Ascomycota. Commonly seen examples include apple scab, ergot, black knot, and the powdery mildews. Species of ascomycetes are also popular in the laboratory. Sordaria fimicola, Neurospora crassa and several species of yeasts are used in many genetics and cell biology experiments. Penicillium species on cheeses and in the antibiotic industry are examples of asexual taxa, otherwise known as anamorphs, that belong in the Ascomycota. Prior to definitive phylogenetic research, molds such as Penicillium were sometimes classified in an artificial phylum, called the Deuteromycota.
In the past, before the recognition of the fungal kingdom, the sac fungi were considered to be a Class, not a Phylum. The original collective term for them was "Ascomycetes", a label first coined in the 1800s for a rankless nonlichenized taxon based upon the presence of asci. "Ascomycetes" was soon used to include lichenized taxa, and became the standard term, at the class level, for all ascus-bearing species, just as the term "Basidiomycetes" became used for their basidium-bearing counterparts. Elevation of the taxonomic rank of the Ascomycetes resulted in the names Ascomycetae, Ascomycotina, and finally Ascomycota. The names Ascomycota, Ascomycetes, etc. are based upon the term "ascus". Together, the Ascomycota and the Basidiomycota form the subkingdom Dikarya. The more familiar term, Ascomycetes, is still loosely used, e.g. at fungal forays it is often said of a fungus, such as Peziza, "It is an ascomycete, not a basidiomycete" in reference to their sexual reproductive mode. The terms are further abbreviated to "ascos" and "basidos" which are not officially sanctioned technical names.
There are 3 subphyla
