Flora of New Zealand Series

Holotype: Tasmania. Hansen's Peak, 1136 m on quartzite-schist. G.C. Bratt 67/527, FH.

Thallus large, coarse, to 9 cm tall, sparingly branched, holdfast well-developed. Pseudopodetia stout 1-3(-5) mm wide, terete, covered with a ± continuous, coarsely scabrid, verrucose-areolate cortex, apices of pseudopodetia often eroded-sorediate. Phyllocladia rather sparse, variable, often most distinct at the apices of small, clustered secondary branchlets, terete, finger-like at first, becoming coralloid-branched. Cephalodia conspicuous, stalked, large, to 3 mm diam., wrinkled, scrobiculate, surface minutely areolate, distinctly grey-blue. Soredia white or greyish, granular, rather sparse, developed on the ends of pseudopodetia, possibly the result of insect damage. Apothecia rare, terminal 1-3 mm wide, disc black, plane at first and thinly marginate, convex and immarginate at maturity. Ascospores 2-5 per ascus, clavate-fusiform, 1-3-septate, 25-35 × 5-7 µm. Chemistry: Atranorin, fumarprotocetraric and protocetraric acids; perlatolic and anziaic acids in apothecia only.

N: Kaimanawa Ra. S: Westland (Kelly Ra.). Otago (Mt Ellespie, Stag Pass, Alabaster Pass,) Southland (above Dusky Sound, Mt Clerke, Mt Hodges). St: (Mt Allen, Tin Ra.). Subalpine, 750-2100 m; rather rarely collected.

Australasian

Sorediate specimens of S. trachyphloeum are distinguished from S. corticatulum by differences in height and robustness of growth (S. corticatulum rarely exceeds 25 mm in height and lacks an obvious holdfast, as well as having smaller, more delicate branches, which are generally copiously sorediate and not merely terminally so as in S. trachyphloeum). S. trachyphloeum is subalpine, while S. corticatulum is mainly lowland and rarely found in alpine or subalpine habitats; and the two species differ in chemistry (S. corticatulum lacks fumarprotocetraric acid). Non-sorediate species (S. argus, S. colensoi and S. ramulosum) are distinguished from S. trachyphloeum by differences in chemistry, morphology of phyllocladia, cephalodia and apothecia, and texture of the cortex.