Evolution of fungi
Origin and diversification of fungi through geologic time
Fungi diverged from other life around 1.5 billion years ago, with the glomaleans branching from the "higher fungi" (dikaryans) at ~570 million years ago, according to DNA analysis. (Schüssler et al., 2001; Tehler et al., 2000) Fungi probably colonized the land during the Cambrian, over 500 million years ago, (Taylor & Osborn, 1996), and possibly 635 million years ago during the Ediacaran, but terrestrial fossils only become uncontroversial and common during the Devonian, 400 million years ago.
From Wikipedia, under CC BY-SA. More on occurri.