Steinera sorediata P.James & Henssen
Holotype: New Zealand. Otago, Mt Cargill, near Dunedin, near summit on more or less bare rocks with Menegazzia circumsorediata. P. James, NZ 2099/2, 9.i. 1963, BM!
Thallus mainly placodioid, spreading, to 6 cm diam., rather loosely attached, margins conspicuously lobate, muscicolous, terricolous or saxicolous, apices and margins often slightly raised, contiguous except at apices, ± flabellate, 1.5-2.5 mm wide, often imbricate, radially fissured, irregularly radiate and corrugate, sometimes with transverse, anastomosing cracks. Upper surface pale greyish-mauve, grey or pale stramineous, markedly scabrid-roughened, especially towards lobe apices, centrally subcrustose, ± continuous with deep, partially interconnecting cracks, sorediate. Soralia numerous, originating from breakdown of ridges, rounded, oval or elongate, becoming irregular and ± confluent and covering thallus, soredia pale blue-grey or lilac, coarsely granular, rarely with finger-like to coralloid isidia which become sorediate. Apothecia rare, scattered, 0.4-7 mm diam., at first innate, becoming emergent, with a slightly elevated thalline margin at maturity, disc bright red-brown to brown, smooth or roughened, concave or plane, margins rather thin, 0.5 mm wide, smooth or ± entirely granular-sorediate. Ascospores acicular-fusiform, with one or both ends tapering,(37-)45-57(-75) × (5-)5.5-7(-8) µm, 5-7-septate. Pycnidia not seen.
N: Taranaki, Mt Egmont S: Otago, Mt Cargill, and Flagstaff Hill near Dunedin; subalpine, 600-700 m.
Endemic
S. sorediata is distinguished from other members of the genus by the presence of soredia. The presence of multi-septate, ± acicular spores suggests that the species is possibly closely related to the non-sorediate S. polymorpha. However, there are features of the anatomy and ontogeny of the two species which suggest that they cannot be considered a species pair.