Thallus brown, heteromerous; composed of flat tufts 4–5 cm across, consisting of imbricate squamules. In inner part, squamules 4–5 mm high, erect, ±terete, homoiomerous, 0.2–0.25 mm diam., simple or irregularly divided at apex; at margin of tufts squamules cuneiform, to 2 mm wide, with irregular projections. In vertical section (flat parts), upper cortex 4–5 µm high, consisting of colourless hyphae lying parallel to the surface, subtended by a layer 40–50 µm high, consisting of densely agglomerated hyphae perpendicular to the surface, brownish in uppermost part but colourless further down; below that a colourless, loose medulla, 50–60 µm high, with short chains of cyanobacteria; and below that a massive layer, 130–140 µm high, consisting of a textura intricata; lower cortex absent, but thallus with strongly conglutinated hyphae and with short, loose hyphae ends. Photobiont Nostoc; individual cells 3–5 µm diam.
Apothecia not observed.
Conidiomata not observed.
Chemistry: no lichen compounds detected.
Distribution and Ecology: Known only from the summits of mountains on the southern New Zealand shelf islands (Campbell Island, Auckland Island); the type growing on acidic soil and other specimens growing on montane rocks.
Remarks: Because this species is not fertile, its generic placement is tentative. However, its general appearance, lack of lichen substances, and lack of rhizines strongly suggest a placement in Protopannaria. The new species differs from the two other, somewhat similar, subantarctic species, P. alcicornis and P. austro-orcadensis, in the broad and flattened marginal lobes and the lack of a distinct lower cortex - the two other species both having marginal lobes that are flat-lying, subterete and little broadened and a thin, but distinct, pseudoparenchymatous lower cortex.