Growing on a decaying Trametes on a log. In redwood forest.
Myxomycetes: Arcyriaceae: Arcyria major
On bryophytes covering a fallen log in mixed broadleaf/podocarp forest.
Under the bark of a fallen Oak
Myxogastria or myxogastrids, formerly known as Myxomycota, is a class of Mycetozoa, itself a grouping of slime moulds, that contains 5 orders, 14 families, 62 genera and 888 species. They are colloquially known as the plasmodial or acellular slime moulds.