Nephroma rufum (C.Bab.) P.James
N. resupinatum var. rufa Church. Bab. Fl. N.Z. 2: 272 (1855).
Lectotype: New Zealand, South Island. Milford Sound. D. Lyall, BM.
Thallus thin, lobate, orbicular to spreading, 1-10 cm diam., corticolous and saxicolous. Lobes 3-8 mm wide and 3-12 mm long, closely appressed centrally, ascending apically, margins entire, sinuous. Upper surface dark reddish-brown or greyish-brown or grey (shaded forms), smooth or ± ridged-faveolate especially towards margins, phyllidiate. Phyllidia sparse to abundant, terete, 0.2 mm diam., 0.5 mm tall, or becoming ± flattened-squamulose to 1 mm diam., scattered over upper surface, singly or in groups. Lower surface dark brown to black, wrinkled, shining or matt, glabrous or microscopically pubescent or finely scabrid. Apothecia subrotund to reniform, 3 × 5 mm diam., with thin, denticulate margins, cortex above apothecia wrinkled, scabrid-areolate, disc red-brown. Ascospores colourless to pale reddish-brown, 3-septate, 15-20 × 5-7 µm. Chemistry: Hopane-15α, 22-diol, and unidentified pigments, occasionally 7β-acetoxyhopan-22-ol (tr.).
N: Te Kotukutuku (Colenso 5097 WELT). S: Nelson (Aniseed Valley); Canterbury (Nina Valley near Lewis Pass, Banks Peninsula, Peel Forest, Lake Tekapo), Otago (Lake Ohau, Routeburn Valley, Trotters Gorge, Akatore, Kaka Point), Southland (Doubtful Sound). On damp rocks and tree trunks in deep shade and moist, humid situations.
Australasian
N. rufum differs from N. helveticum in the near glabrous lower surface, the entire lobe margins, the scattered laminal phyllidia, the different spore size and the different chemistry. It appears widely distributed in New Zealand although is still very much undercollected. It occurs also in Tasmania.
