Description:
Thallus effuse, consisting of small, discrete patches up to 0.5 mm across, but forming larger patches in depressions; areolate, areoles c. 0.1 mm across; creamy-white with a minutely arachnoid surface, cortex absent; often with a black, fimbriate prothallus. Medulla with numerous minute crystals giving it a pale brown colour, mostly dissolving in K. Photobiont chlorococcoid, cells 10–12 µm diam.
Apothecia lecideine, black, blue-black when wet, ±orbicular to slightly elongate, often with a wavy margin, 0.3–0.6 mm diam., flat to convex, ±immarginate; flat with a thin proper margin when young, margin 0.02 mm wide, concolorous with disc or unpigmented; disk rough. Thecium 35–40 µm tall, paraphyses unbranched, sparingly branched towards apex, septate, lax in K, c. 2 µm wide, slightly swollen to 3 µm at apex, upper 5–10 µm with blue-black pigment; epihymenium granular with scattered minute colourless crystals, mostly dissolving in K. Hypothecium hyaline, composed of randomly orientated hyphae. Asci ±cylindrical when young, becoming clavate, Bacidia-type, 25–30 × 12–20 µm; ascospores hyaline, 1-septate, 9–11 × 4–5 µm. Exciple poorly developed with narrow anastomosing medullary hyphae with swollen, ± blue-black pigmented cortical cells; with numerous minute colourless crystals dissolving in K.
Conidiomata: not observed.
Chemistry: C–, K+ yellow, Pd–; atranorin by tlc.

Distribution and Ecology: Known only from the type collection, which is on the upper surface of a flat, angular quartzite pebble, approximately 10 × 5 cm area.

Comments: The dispersed thallus of this species is probably a result of the substratum upon which the lichen was growing and is probably not a diagnostic character. It is probable that other specimens of this species will have a more continuous, areolate thallus.

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Thallus & Apothecia