Graphidaceae of Central French Guiana

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Sarcographa sp. Harris 33372

Thallus greenish to yellowish, thickly cartilaginous and unevenly developed, tuberculate, cracked and appearing aereolate; thin prosoplectenchymatous layer smooth and slightly shiny; K+ red, P-; lirellae crowded and pressed together in dense raised creamy to whitish stromata; stromata weakly raised, with margins defined by outer labia of lirellae, not at all exceeding margins. Stromatic tissue of moderately densely woven colorless hyphae with many large crystalline inclusions inspersed throughout upper layers of bark. Disks grayish, narrowly exposed (0.03-.08mm) lightly white pruinose, bordered by raised white crumbling margins often and split from surrounding stromatic tissue and thallus by one deep lateral fissure. Lirellae sinuous and confluent, branching frequently; exciple not carbonized and not darkened below, pale to yellowish laterally in a thin band, not clearly differentiated, I-. Hypohymenium colorless to yellowish, convex below. Epihymenium appearing brownish in cross section. Hymenium not inspersed, colorless. Paraphyses simple, nonbranching above and slightly rounded clavate apically, septate. Ascospores 8/ascus, 5-7x13-17µ, thick walled brownish 4-locular ends rounded ±oblong to slightly tapered at ends, apical lumina larger than medial, I-. No lichen substances.

This is similar to S. intricans (Nyl.) Müll-Arg except for lacking substances