Palaeos		Ascomycota
Fungi		Ascomycota

The Ascomycota

Fungi
|--Chytridomycota
`--+--Zygomycota
   `--+--Basidiomycota
      `--ASCOMYCOTA
         |--Taphrinomycotina
         `--+--Saccharomycotina
            `--Pezizomycotina

The 73rd plate from Ernst Haeckel's Kunstformen der Natur (Artforms in Nature), depicting Ascomycetes.

The Ascomycota are the largest division/phylum of Fungi, with over 64,000 species. They are also known as the Sac fungi, so-called because of the presence of microscopic spore- producing organ called an " ascus" (or askos, if you want to get into the ancient Greek for "sac" or "wineskin"), hence the name.