Nephroma cellulosum (Ach.) Ach.
Lichen cellulosus Sm. in Ach., Meth. Lich.: 242 (1803).
Thallus orbicular to spreading, 5-15 cm diam., corticolous or muscicolous. Lobes rounded, flattened, closely attached centrally, subascendent apically, margins entire, rounded, sinuous. Upper surface markedly faveolate-reticulate, faveolae 2-3 mm wide, separated by well-defined ridges, olive-brown to reddish-brown to greyish-red or grey (shade forms), matt or shining in parts, sometimes white-maculate (×10 lens). Lower surface distinctly bullate, shining, creamish-buff at margins, dark grey-brown centrally, glabrous. Apothecia pale to dark brown, 5-10 mm broad and 2-5 mm long with a narrow, entire margin. Ascospores biseriate, pale brownish, 2-septate, 14-20 × 7-8 µm. Chemistry: Zeorin, unidentified terpene, perlatolic acid and unidentified pigment (±).
N: South Auckland (King Country). S: Nelson (Lake Rotoiti), Canterbury (Boyle River, Arthurs Pass, Banks Peninsula), Otago (Matukituki Valley, Kaka Point). On trees, rarely mosses in damp, humid places. Often locally common on Leptospermum bark.
Austral
N. cellulosum is characterised by the strongly scrobiculate, faveolate-impressed upper surface, and the bullate lower surface, whitish and shining at margins. It is related to N. lepidophyllum but lacks phyllidia. The dark, reddish-brown to greyish colour can make it difficult to find in shaded forest interiors where it often grows, and doubtless its range is wider than that recorded above. It is known also from Tasmania, Juan Fernandez and Southern Chile, and was first discovered by Archibald Menzies in 1787, in Staten Island near Cape Horn. Menzies' specimens were named Lichen cellulosus by James Edward Smith, who sent them to Acharius for description in his Methodus.
