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Family: CollemataceaeGenus: Scytinium
Thallus thickish, lobate to minutely foliose or squamulose, heavily wrinkled when dry; lobes usually small, (0.1-) 0.2-1 mm wide and to 2.5 mm long, swelling greatly when wet, sometimes ascending and appearing shrubby. Thallus with upper and lower cortex composed of a single layer of angular cells, with a broad medulla composed of intertwined hyphae with chains of the Nostoc photobiont, all within a gelatinous matrix. Upper surface dark olive- or red-black, wrinkled to plicate, concave at the circumference, often densely granular isidiate, the isidia 60-100 µm diam.
Anamorph: not known.
Teleomorph: ascomata apothecia, 0.5-3 mm diam., absent to numerous, laminal. Disc concave in young apothecia, becoming ± flat in older ascomata. Thalline exciple swollen, entire, or sometimes slightly granular-isidiate. Epithecium reddish brown, hymenium hyaline, hypothecium pale brown. Interascal tissue of paraphyses, numerous, conglutinate, simple, the apices ± swollen. Asci clavate to cylindric-clavate, the wall K/I + blue and the apical dome K/I+ pale blue with a dark blue axial tube, 8-spored. Ascospores 25-32 x 10-12 µm, ellipsoidal to fusiform, often apiculate at one or both ends, submuriform to muriform, usually with four or five transverse septa and one longitudinal septum, hyaline, smooth-walled, without an epispore, gelatinous sheath or appendages.