in Nimis & Poelt, Studia Geobot., 7, suppl. 1: 72, 1987.
Distribution: C - Sar.
Description: Thallus crustose, continuous to areolate, pale orange, forming small, rounded, 5-8 mm wide, often confluent patches on the thalli of Rinodina alba and other crustose species, the marginal areoles sometimes slightly lobulate, 0.2-0.5 mm wide. Cortex thin, paraplectenchymatous, the cells up to 5 μm thick; medulla poorly developed, I-. Apothecia sparse or clustered, up to c. 1 mm across, but often smaller, with a red-orange, mostly flat disc, and a thick, at least at the beginning prominent margin. Exciple of strongly conglutinated hyphae, radially expanded at margin; epithecium orange-brown, K+ red; hymenium c. 70 μm high; paraphyses 1.5-2 μm thick at base, the 2-3 apical cells (those reaching the surface of the disc) rounded to markedly swollen, up to 7 μm wide; hypothecium colourless. Asci 8-spored, clavate, Teloschistes-type. Ascospores 1-septate, polarilocular, hyaline, broadly ellipsoid to globose, 9-15.5 x 7.5-9 μm, the globose ones 7-8 μm wide. Photobiont chlorococcoid. Spot tests: thallus and apothecia K+ red, C-, KC-, P-. Chemistry: thallus and apothecia with parietin (major), fallacinal, emodin, teloschistin and parietinic acid (minor), corresponding with chemosyndrome A of Søchting (1997).
Note: hitherto known only from the type locality and from another coastal station near Santa Teresa di Gallura in northern Sardinia (Vondrák in litt.), this species should be looked for throughout the Mediterranean, wherever the host is present.