Lich. Mexique: 16 (1914).

Synonyms: Index Fungorum

Protolog: Data lacking.

Type locality: Mexico, Puebla, Tepoxuchitl, 1910, Friar Nicolas (W - lectotype). Lectotypification by Knudsen & Morse (2009: 148).

Barcode: Data lacking.

Coordinates: Data lacking.

Thallus: crustose, areolate, indeterminate, contiguous or dispersed, covering to 5 cm2 or more. Areoles 0.2-1.5 mm in diam., irregular to round in shape, becoming lobulate and subsquamulose, usually with a distinct rim, upturned or curling when dry, usually black, broadly attached at center, more narrowly attached with development of apothecium and lobes, becoming subsquamulose without forming a distinct stipe; upper surface gray to dark brown, finely pruinose, or with coarse encrustations of pruina, the pruina white or blue-green or rose-tinted, the pruinose areas turning brown when wetted; lower surface rarely pale, usually reddish-brown to black, corticate, textura globularis, 10-50 µm thick, formed of paraplectenchyma, possibly differentiating from apices of prosoplectenchyma of medulla, mostly round, 4-6 µm in diam., with pigmentation in thick outer wall 1-2 µm wide; epicortex lacking or indistinct, the surface usually encrusted with pruina, fine or coarse, not dissolving in KOH; eucortex 10-50 µm thick, though often thin around expanded apothecia, cells irregular, mostly angular, 2-5 µm in diam., generally textura angularis though sometimes cells aligned in vertical rows, paraplectenchymatous (poorly observed in water in some specimens, not particular clearer in K, clearing in HCl), upper layer, brown or rarely bleached white, 5-20 µm, lower layer hyaline; algal layer even, uninterrupted by hyphal bundles, 30-100 µm thick, algal cells mostly 10-12 µm in diam., usually lacking beneath apothecia; medulla dense,.

Photobiont: Data lacking.

Chemistry: No lichen substances.

Ecology: Data lacking.

Molecular data: Genbank

Distribution: Database

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