Niebla infundibula is characterized by a large massive rigid thallus divided into sub[terete] branches spreading from a holdfast, to 10 cm high and 15 cm across above the base, and further recognized by containing divaricatic acid and by the large pycnidia.

Similar species are Niebla juncosa, which differs in having a more fragile thallus with branches that break off as evident from the thallus falling apart in the herbarium, including breaking apart at the base, and by its less glossy cortex and less conspicuous pyncidia (due to their smaller size), and Niebla eburnea, also with smaller pycnidia (200–350 μm long), but generally recognized by its pastry-like, or ivory-like, cortex.

[1] Niebla infundibula was first recognized by Richard Spjut, accompanied by Richard Marin and Thomas McCloud, 19 May 1986, just south of Punta Negra on rock outcrops along a ridge that appeared to receive more precipitation from ocean fog than nearby ridges and peaks (Plate 1D in Spjut’s 1996 revision of Niebla and Vermilacinia).

[1] This area was observed during May 1985 by Spjut—while he and Marin were collecting samples of lichens in search of new drugs to treat HIV—to have fog lingering over the peaks and ridges most of the day.

[6][7] Specimens later studied in the United States National Herbarium (Smithsonian Institution)[8] and on loan from the University of Colorado and Boulder were also recognized to belong to N. infundibula.