Flora of New Zealand Series

Lectotype: New Zealand. Otago, Mt Maungatua, 900 m on schist rock. J.S. Thomson ZA 185, W.

Thallus dwarf, to 8 mm tall. Pseudopodetia simple, erect, finger-like, occasionally bifurcating at apices, nodular-papillate at first, becoming terete, corticate, cortex continuous, sometimes horizontally cracked, smooth or wrinkled, often shining, greyish-white below, becoming purplish-brown above and mottled, with small, black pycnidia at apices. Phyllocladia absent. Cephalodia basal, cerebriform and slightly convoluted, greenish-black, surface rather scabrid. Apothecia terminal, disc black 1-5 mm wide, deeply concave at first becoming persistently plane at maturity with a prominent, raised, pale, red-brown margin, thalline exciple smooth or wrinkled, red-brown. Hypothecium 60-75 µm thick, red-brown. Ascospores broadly fusiform, 6-8-septate, 30-50 × 4-7 µm Chemistry: Atranorin, protocetraric and fumarprotocetraric acids.

N: Kaimanawa Ra., Ruapehu, Tararua Ra. S: NW Nelson to Fiordland, Inland Kaikoura Ra. to Mt Maungatua. St: Mt Anglem to Port Pegasus (Smiths Lookout). C: On rocks in exposed alpine situations.

Australasian

S. caespitosum is closely related to S. gregarium and S. loricatum, the two other species in New Zealand which lack phyllocladia. They form a natural group which seems to have evolved in New Zealand in the mountains of the South I. S. caespitosum differs from both S. gregarium and S. loricatum in the following characters: pseudopodetia smooth, shining, purplish-brown towards apices, cephalodia greenish-black not pale, apothecia at maturity plane and consistently marginate, and hypothecium red-brown.