PDD 16110, 17576, 48188.

Fruiting body a stalked sporangium, gregarious, 1.0–1.5 mm tall. Sporotheca subglobose or lens-shaped, usually nodding but occasionally erect, 0.3–0.7 mm in diameter. Stalk noncalcareous, slender, tapering, longitudinally wrinkled, and usually dark in colour but becoming less so toward the apex. Hypothallus membranous, irregular, colourless to dark, often scanty and then inconspicous. Peridium consisting of a single layer, membranous, more or less encrusted with lime, white to dull grey, the upper portion splitting into irregular fragments. Columella absent. Capillitium consisting of colourless slender threads with interspersed small, white lime nodes. Spores black in mass, pale lilaceous brown by transmitted light, minutely spiny or nearly smooth, 8–10 µm in diameter. Plasmodium colourless, watery white or grey.

Cosmopolitan (Martin & Alexopoulos 1969). First reported from New Zealand by Lister & Lister (1905), based on specimens from Dunedin and Stewart Island. Also known from Auckland, Coromandel, Nelson, Buller, South Canterbury, Dunedin, Southland, and Stewart Island.

Decaying wood or (more often) bark; also occurring on the old sporocarps of wood-decaying fungi.

Martin & Alexopoulos (1969), Nannenga-Bremekamp (1991), Stephenson & Stempen (1994), Neubert et al. (1995), Ing (1999).

This species and Physarum viride are very similar morphologically, but the former shows no evidence of the yellow or orange colour characteristics of the latter. Physarum album is listed as P. nutans in most modern treatments of the myxomycetes, but according to Lado (2001) the former name has priority and is the one used herein.