Flora of New Zealand Series

Thallus subsquamulose or crustose-subfoliose, rosette-forming to spreading, thick, tartareous, white or greyish-white, without a distinct marginal prothallus. Photobiont green, Trebouxia. Apothecia lecideine, proper margin thin, concolorous with disc, often occluded, disc black or brown-black, with or without a grey-white pruina. Hypothecium brown-black. Epithecium granular, brown-black. Asci clavate, 8-spored. Paraphyses septate, filiform, brown-capitate at apices. Ascospores brown, ellipsoid, 1-septate.

Diploicia, a genus of c. 8 species is included in the Physciaceae and is characterised by the brown, 1-septate spores and the distinctly subsquamulose or subfoliose-crustose thallus with conspicuous plicate-radiate margins. One species is recorded from New Zealand from coastal rocks.