Syn. Meth. Lich. (Parisiis) 1, (2): 290 (1860).

Description: Lichen. Thallus fruticose. The species is corticolous, typically draping branches and twigs throughout the transition zone. It has rarely been collected and is possibly overlooked because of its similarity to R. usnea of which this taxon may just be a chemotype. Galapagos specimens of R. anceps appear overall thinner and less contorted than specimens of R. usnea, but this variability is not a reliable diagnostic morphological character to distinguish the two taxa.

Chemistry: Usnic acid.