Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Apothecia: scattered, not in discrete necrotic patches, not concentrically arranged, fawn to pale brown initially, becoming finally dark brown to black, irregular in shape, at first elongate or branched, bursting through the cortex, jagged remnants of which remain at the margins of the young apothecia, slit-like and concave at first, finally becoming ±circular and slightly convex with the remnants of cortical tissue ±excluded, 0.2-0.3(-0.5) mm in diam exciple: hyaline to pale brown, K-, poorly developed, 10-18 µm thick at the uppermost part, cells 2.5-5 µm in diam. hymenium: hyaline to pale brown above, hyaline below, 50-60 µm tall; hypothecium: hyaline, poorly differentiated or sometimes absent, structurally similar to the exciple, 6-10 µm thick paraphyses: simple or sparsely branched, 2-3 µm thick below, gradually thickening towards the apices; apices: hyaline or pale brown, not encrusted, 3.5-4.5 µm thick asci: when young with an ocular chamber but when mature often with a downward convex central projection into the ascus cavity, 50-70 x 10-15 µm ascospores: ellipsoid to soleiform, apices rounded to somewhat attenuated below, (0-)1(-2)-septate, constricted at the median septum, (12-)13-17(-19) x (4-)4.5-6 µm Pycnidia: unknown. Hosts: thalli of Peltigera species (mainly P. didactyla), in Mexico on P. fibrillosa World distribution: Africa, Australia, Europe, North and South America Sonoran distribution: once collected in Chihuahua