PDD 68541, 72934, 72944

Fruiting body a sessile sporangium, usually crowded but occasionally scattered, depressed-pulvinate and often polygonal by mutual contact, chestnut to dark brown or nearly black, 0.1–1.5 mm in diameter. Hypothallus contiguous for a group of sporangia, colourless and often inconspicuous. Peridium consisting of two layers, the outer layer sometimes hoary or covered with amorphous or crystalline lime (calcium oxalate) deposits, closely appressed to the membranous inner layer, dehiscence circumscissile by means of a definite preformed operculum. Capillitium consisting of slender, simple or branched free elaters, yellow, 2–3 µm in diameter, minutely warted or spiny. Spores bright yellow in mass, pale yellow by transmitted light, minutely warted, 9–12 µm in diameter. Plasmodium colourless or pale yellow.

Cosmopolitan. First reported (as Perichaena quadrata) from New Zealand by Rawson (1937), based on a specimen collected in South Canterbury. Also known from Auckland, Westland, and Campbell Island.

Decaying bark and (less commonly) wood; sometimes occurring on leaf litter and dung in moist chamber cultures.

Martin & Alexopoulos (1969), Nannenga-Bremekamp (1991), Neubert et al. (1993), Stephenson & Stempen (1994), Lado & Pando (1997), Ing (1999).

Typical fruitings of this species are easily recognised, but atypical fruitings may be mistaken for Perichaena corticalis. The sporangia of the latter species, however, are not markedly depressed or angular. Perichaena depressa is common on old decaying fronds of nikau palm.