Physcia dubia #

Taxon #

Physcia dubia

Organization #

Physciaceae

Identification #

Physcia dubia is a gray, foliose lichen which forms irregular thalli or rosettes. It produces soredia, sorediate apothecia, but does not have isidia. It is sorediate, gray, and saxicolus, and therefore could be mistaken for P. caesia. P. dubia, however, has labriform soralia while those of P. caesia are convex and rounded.

Substrate #

saxicolous, on antler and bone, lignicolous, in sites manured by birds (Spribille et al. 2023)

Chemical Tests #

cortex: K+ yellow, C-, KC-, Pd+ yellow; medulla: K-, C-, KC-, Pd- (CLH)

Notes #

Ubiquitous throughout Alaska (CLH)