Niebla arenaria is a fruticose lichen that grows along the Pacific Coast of North America in the fog regions of the northern peninsula of Baja California from near Colonet south to Morro Santo Domingo.

[1] Niebla arenaria is recognized by a hemispherical thallus similar to the reindeer lichen Cladonia rangiferina, loosely attached to soil without a holdfast, intricately divided into narrow tubular prismatic branches shortly bifurcate near branch tips, the tips usually with black dot-like pycnidia, and by containing the lichen substance salazinic acid.

It sometime forms pure colonies along sandy shores of bays and peninsulas, possibly as a result of the black-tipped branchlets breaking off and reproducing.

[2] These two groups of lichen substances could be separated by the medulla reaction to para-phenylenediamine, depsidones (pd+), depsides (pd-).

[2] It was stated that: "This beautiful terricolous species forms extensive discontinuous mats...on beach terrace deposits atop coastal bluffs south of El Rosario and beyond, often in densities great enough to color the landscape yellow-green.