Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Fissurina columbina: (Tuck.) Staiger, Biblioth. Lichenol. 85: 130 (2002). Thallus: crustose, continuous, smooth to slightly uneven, waxy to cartilagineous surface: ochre, pale brownish green or pale gray, often paler around the lirellae Apothecia: fissurine, lirellate lirellae: irregularly branched, 0.5 margin: thalline one slightly paler than the rest of the thallus, inner margins white to grayish white disc: not visible or narrow and pale gray exciple: not carbonized at all, poorly developed at the base, laterally with yellowish hyphae and bark cells integrated, often with (Caoxalate?) crystals marginally, sometimes with pale brown apices epihymenium: not differentiated hymenium: hyaline, not inspersed, 100-110 µm tall paraphyses: with hyaline sometimes ±warty tips periphysoids: not well developed subhymenium: hyaline, c. 10 µm thick asci: clavate, 90-100 x 15-20 µm, 6-8-spored ascospores: hyaline, muriform, 5-8/2-4-locular, with quite thick spore wall (c. 2 µm), 20-33 x 10-17 µm, I+ blue-violet Pycnidia and conidia: not found Spot tests: cortex and medulla K-, C-, KC-, P+ yellow or P- Secondary metabolites: psoromic acid or unknown fatty acid (Rf-values 7/2/1 in solvent system A, B', C), or none detected. Substrate and ecology: on bark in humid forests World distribution: tropical and subtropical regions of the New World and extending north to California Sonoran distribution: not yet found but expected due to occurrence in coastal, central California and farther south. Note: The only specimen investigated here had brownish discs and a brownish "epihymenium" due to the presence of parasitic fungi.