Arcyria obvelata (Oeder) Onsberg 1979
Reproductive structure:- stalked structure (sporangium), 1.5-2.0 mm tall initially, expanding to 4-12mm after after spores are released.
Sporotheca:- the spore-containg portion of the sporangium, cylindrical, bright to pale yellow, fading to pale ochraceous or beige (rarely with pale flesh coloured tints), 0.3-0.5 mm in diameter.
Stalk:- usually very short, slender beige or yellow.
Hypothallus:- deposited layer by plasmodium (acellular, multinucleate mass of protoplasm that is the main feeding stage of the slime mould (myxomycete) life cycle) is contiguous under group, colourless, initially watery white.
Peridium:- the spore mass covering; persisting in mature reproductive structure as a cup-like structure (calyculus) formed from the basal portion of the perdium and surrounding the base of the spore mass. This is small, shallow, flaccid, translucent, spiny-reticulate on the inner surface
Capillitium:- a system of sterile elements found within the spore mass, Strongly elastic, deciduous, flaccid and drooping, consisting of very fine threads, sculptured with half-rings,spines, and fragmentary reticulations.
Spores: pale yellow in mass,almost colourless by transmitted light, nearly smooth with a few scattered warts
Habitat:- usually on dead decaying wood.
Comments:- The pale yellow colour and greatly expanding (to the point of becoming "fluffy" in mature specimens) capillitium make Arcyria obvelata an easy species to recognise in the field. This species is listed as A. nutans in most taxonomic treatments of the mycomycetes.
The above information is after S.L. Stemphenson, 2003, Myxomycetes of New Zealand Vol. 3. The Fungi of New Zealand.