PDD 3615, BPI 810298.

Fruiting body a stalked or sessile sporangium, clustered or scattered, the stalked forms 2 mm or more tall. Sporotheca subglobose, obovoid or wedge-shaped, occasionally somewhat elongated, 0.5–1.0 mm in diameter. Stalk, when present, slender, white to pale ochraceous or translucent, often branched, merging into the hypothallus. Hypothallus membranous, yellow or white, more or less reticulate and giving rise to the stalk. Peridium consisting of two layers (appearing single when the outer layer is poorly developed), outer layer usually strongly calcareous, greyish white above and white or ochraceous below, with scattered deposits of lime, the inner layer membranous, hyaline, delicate, dehiscence occurring mostly towards the apex, the outer layer of the peridium persisting below as a poorly defined cup. Capillitium dense, consisting of numerous white, rounded or lobed lime nodes connected by rigid, hyaline filaments, the nodes sometimes massed in the centre of the sporotheca and then forming a loose pseudocolumella. Spores black in mass, dark purplish brown by transmitted light, prominently warted, with larger warts grouped in clusters separated by pale bands, 10–15 µm in diameter. Plasmodium white.

Apparently confined to temperate and cool temperate regions of the world (Ing 1999). First reported from New Zealand by Macbride (1926), based on a specimen cited without naming a specific locality. Also known from Waikato.

Leaf litter, straw, and other types of plant debris.

Martin & Alexopoulos (1969), Nannenga-Bremekamp (1991), Ing (1999).

Most fruitings of this species tend to be small, and they often occur in situations where they are easily overlooked, e.g., straw heaps and accumulations of leaf litter. When the stalk is absent or not readily apparent, Physarum straminipes might be confused with P. cinereum or with the sessile sporangia of such species as P. compressum. However, the pale bands on the spores are distinctive (Nannenga-Bremekamp 1991).