Thallus: crustose, epiphloedal or eplithic, effuse, well developed, c. 350 µm thick, rimose to minutely areolate to verrucose or composed of small, irregular, sometimes plicate or rugose squamules, scattered at first but soon forming a thick, uniform, tartareous or furfuraceous crust; determinate, with a dark brown-black prothalline border surface: white, creamy, or +rose-pink (soon fading to white or pale gray), overlain by an epinecral layer c. 40 µm thick medulla: chalky, well differentiated Ascomata: rounded or often oblong or irregular but unbranched, sessile, constricted at the base, 0.4-1.3 mm in diam., isolated or aggregated, disc: black, plane becoming convex, gray-pruinose when young margin: black, thin, smooth, prominent but finally disappearing, entire to crenulate, granulose or verrucose exciple: dark brown internally, with some hyphae visible in the more external part, branched and interwoven; walls: reddish brown, with occasional granules or crystals on the surface, insoluble in K pseudothecium: yellowish brown, subcontinuous, dark, 45-60 µm thick, I+ blue hymenium: hyaline, (75-)100-115 µm tall, I+ yellowish brick red or wine red but upper part sometimes I+ blue; paraphysoids: loose, slightly branched (forked once or twice below the tips), not anastomosing, +entangled and twining, c. 2 µm wide; tips: not anastomosing or coralloid, 3-5 µm wide, clavate-thickened, pale gray, pigmented in the internal part of the wall subhymenium: brown, 15-25 µm thick hypothecium: dark brown-black, merging into the lateral part of the exciple asci: cylindrical-clavate, (65-)78-106 x 13-16.8 µm, 8-spored ascospores: hyaline, transversely 3(-4)-septate, straight or mostly a little curved, fusiform, blunt-ended (19.6-)24-28 x 5-6(-7) µm; wall: thin and uniform, without gelatinous sheath conidia: filiform, 5-6 x 1 µm Spot tests: thallus K+ light yellow to orange or K-, C+ pale yellow or C-, KC-, P+ yellow(-orange) Secondary metabolites: psoromic and consporomic acids. Substrate and ecology: on various barks or seashore rocks, coastal to low montane World and Sonoran distribution: southern California, Baja California, including Isla de Guadalupe. Note: Lecanactis californica and its synonym L. zahlbruckneri were incorrectly listed as synonyms of Sigridea californica (Tuck.) Tayl. (basionym: Dirina california Tuck.) by Esslinger and Egan (1995).