Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Thallus: fruticose, caespitose, growing tufted clumps, branches: angular to flattened to subcylindrical, 1-5 mm wide, up to 5 cm in length surface: rough, papillate nearly isidiate cortex, tubercules on the surface, green, to greenish yellow medulla: white, with a coalesced structure in the interior, but not multi-stranded as in N. homalea Apothecia: terminal or subterminal, mostly marginal, up to 6 mm in diam. disc: pale, plane to convex, cupped when immature asci: clavate, 8-spored ascospores: hyaline, 1-septate, fusiform, straight to gently curved, 11-14 x 3-5 µm Pycnidia: black, immersed Spot tests: all negative Secondary metabolites: usnic acid and unidentified triterpenes. Substrate and ecology: on coastal rocks and cliffs World and Sonoran distribution: endemic to the south-central California coast (technically just north of the Sonoran region). Notes: Niebla tuberculata is a tufted, caespitose species superficially resembling a coarse, thicker N. ceruchoides thallus and grows in abundance in the Morro Rock Reserve area on rock. Its cortex is rough and papillate, and there is a dense hyphal aggregation embedded centrally in the medulla. Apothecia are on the terminal branch segments, and the asci are pale. Black pycnidia occur on the cortical papillae throughout the length of the branches. This species lacks the secondary metabolites found in N. homalea, N. ceruchis, or other taxa.