This is a small family of fruticose lichens with relatively thick, pendent or shrubby branches. Almost all species within it share a thick cortex and some degree of conglutinated medulla hyphae. Also most species prefer maritime or otherwise humid habitats.
:Ramalina mostly on trees, pseudocyphellae, chondroid strands in medulla, prosoplectenchymatous cortex, pale pycnidia, bacilliform condia Niebla mostly on rocks, no pseudocyphellae, nearly always on the immediate coast, black pycnidia, rod-shaped conidia
Several additional genera have been proposed, as well. The most important is Vermilacinia, which splits most of Niebla off from N. homalea and N. josecuervoi (based on chemistry and other characters?) Other genera include Desmazieria (= Niebla) and Trichoramalina (= Ramalina). Neither of these are widely accepted yet.
The problem seems to be that there is greater than average plasticity in morphological characters due to environment and substrate within the species of Niebla and Ramalina. Molecular work will be required to make any definitive progress in this area.