15880, 15881.

Fruiting body an aethalium, solitary to gregarious (although usually somewhat separated), pulvinate to hemispherical, at first silvery white but becoming brown, 2–8 cm broad and up to 2 cm thick. Hypothallus white, usually forming a conspicuous margin about the base, becoming inconspicuous when powdered by the spores. Cortex more or less tough cartilaginous, brown, lustrous, smooth to rugose. Pseudocapillitium arising as erect plates from the base, branching in a dendroid fashion with many expansions and ending in a mass of flattened, flexuous threads almost free from the cortex. Spores rust-brown in mass, pale brownish yellow or reddish brown by transmitted light, distinctly reticulate over about two-thirds of the surface, 8–9 µm in diameter. Plasmodium creamy white.

Reported to be cosmopolitan (Martin & Alexopoulos 1969) but probably most common in temperate regions of the Northern Hemisphere. First reported from New Zealand by Lister & Lister (1905), based on a specimen collected in Dunedin. Also known from Auckland and Wanganui.

Decaying wood.

Martin & Alexopoulos (1969), Nannenga-Bremekamp (1991), Neubert et al. (1993), Lado & Pando (1997), Ing (1999).

The fruiting bodies of R. lycoperdon are among the largest produced by any myxomycete and sometimes are as much as 10 cm across. Fruiting bodies that have been mature for more than a day or two often have been invaded by small beetles that feed upon the spore mass.