Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.

Thallus: fruticose, usually unbranched, less commonly branched branches: flattened, usually strap-like and flat, rigid, 1-2.5 cm wide and 2.5-5(-6) cm long surface: green, smooth, often shiny, ridged in some aberrant forms medulla: white, cottony, lacking well formed hyphal aggregates Apothecia: common, primarily terminal, often clumped on the terminal margins, in some plants extending halfway down the margins, 2-4(-8) mm in diam. disc: white, concave, often curled inward and lobed asci: clavate, 8-spored ascospores: hyaline, 1-septate, fusiform, straight to gently curved, occasionally strongly curved, 10-14 x 4-5 µm Pycnidia: black, immersed conidia: straight, rod-shaped, 4-5.5 x 1 µm Spot tests: negative Secondary metabolites: (-)-16α-hydroxykaurane, zeorin, +bourgeanic acid, usnic acid, and, fide Spjut (1996) triterpene T3. Substrate and ecology: on coastal rocks along the immediate coast within strong fog zone influence World and Sonoran distributions: coastal California to Baja California, including the Vizcaíno Peninsula and Cedros Island. Notes: Niebla laevigata has often been confused with N. homalea, but its smooth, shiny cortex and compressed, lanceolate blades are characteristic. Some thalli, particularly those with extremely wide branches, do have some cortical ridging, but they can be separated from N. homalea by close examination. Niebla laevigata occurs on ocean-facing rocks and cliffs and is similar to N. procera and N. ceruchoides in its restriction to the immediate coastal fog zone. The branches (blades) arise from a basal plate that is often blackened, and they crack when bent. The cortex is a palisade formation overlying a thinner supportive layer. In the herbarium white, cottony exudates form along cortical cracks.