ETYMOLOGY: Named after the podocarp wood on which it was collected

The violet colour of the basidiomes and the very dark lamellar margin, together with the reddish-coloured plasmatic pigment of most internal tissues are very distinctive.

M. austroavenacea, M. lividorubra, and M. podocarpi form a group of closely related, brightly-coloured species, all with lamellar margins distinctively dark-coloured and homogeneously sterile: cheilocystidia basically clavate, with long, often contorted excrescences; spores small and amyloid; basidia 2-4-spored. M. oratiensis stands a little apart in having an umbonate pileus, more strongly decurrent lamellae; larger spores; 4-spored basidia, and nodulose pileipellis elements. All bat M. austroavenacea grow on wood.

Microscopically the affinities of these fungi appear to lie with the M. olivaceomarginata (Massee apud Cooke) Massee group, which Maas Geesteranus (1986b) describes as a very variable species, which may appear in a number of colour forms. The main difference is the much smaller spore size of the Southern Hemisphere species compared with the Northern ones. The original description of M. olivaceomarginata by Massee, both in the text (Cooke 1883) and on the figure in Cooke (1881, pl. 1153 (959)), gives the spore size as "6 X 5 µm." (Close to the size for the Southern species) and this has never been reconciled with all later records for this species of approximately 9-13 X 5-7 µm. Recently, Singer (1989) has described a new species of Mycena from Brazil, M. castaneomarginata Sing., which appears , to have many of the microscopic characters of the New Zealand species, including the small spores (6.5-7.5 X 4-4.5 µm.), but is a much smaller fungus and lacks the bright colours. In a field identification key to some Victorian (Australia) species of Mycena, Grgurinovic & Holland (1982) referred to a new species, M. erythromyces nom.inal., which appears from the meagre morphological description to resemble M. oratiensis, no microscopic details were supplied for comparison.