Physciaceae spp. on Macrolichens of Alaska

Physcia adscendens

Mon, 01 Jan 0001 00:00:00 +0000

Physcia adscendens #

Taxon #

Physcia adscendens

Organization #

Physciaceae

Identification #

Physcia adscendens forms whiteish, grayish, to light green thalli of ascending or weakly erect lobes. Abundantly ciliate and with hood-shaped soralia. It is similar to, and sometimes growing with, P. tenella, but that species does not have hood-shaped soralia. This species only rarely produces brown apothecia.

Substrate #

corticolous, ramicolous, saxicolous

Physcia caesia

Mon, 01 Jan 0001 00:00:00 +0000

Physcia caesia #

Taxon #

Physcia caesia

Organization #

Physciaceae

Identification #

Physcia caesia is a very common species of rock dwelling lichen which can be quickly recognized, although there are a few lookalikes. P. caesia forms attractive, light to dark gray thalli which can turn a light bluish or greenish when well-hydrated. Mature specimens will have convex to spherical, gray soralia which are better developed closer to the center of the thalli. It will rarely produce apothecia with black discs and rims which are concolorous with the thalli. Physcia dubia is perhaps the most similar but has labriform soralia rather than the convex, capitate soralia found in P. caesia. P. biziana is another grayish saxicolous Physcia but it lacks soredia. P. stellaris is a corticolous species and is usually abundantly apotheciate (CLH).

Physcia dubia

Mon, 01 Jan 0001 00:00:00 +0000

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)

Physcia tenella

Mon, 01 Jan 0001 00:00:00 +0000

Physcia tenella #

Taxon #

Physcia tenella

Organization #

Physciaceae

Identification #

White to light green thalli of slender lobes with light colored sorediaPhyscia tenella is morphologically similar to P. adscendens but does not form hood-shaped soralia. Specimens on rock can appear similar to Physcia subtilis but that species has soredioid granules rather than true soredia (Esslinger 2017). Ramicolous specimens can look like a species of Heteroderma or Anaptychia, but the hyphae in the upper cortex of those species are parallelly aligned (Kurokawa 1962 in CLH).

Physciella chloantha

Mon, 01 Jan 0001 00:00:00 +0000

Physciella chloantha #

Taxon #

Physciella chloantha

Organization #

Physciaceae

Identification #

Thalli of short overlapping lobes. Greenish gray when desiccated, light green in shade and when hydrated. Producing soredia from labriform soralia. Fertile specimens uncommon. Most likely to be confused with Phaeophyscia orbicularis. That species has longer lobes which form more even rosettes and is often abundantly apotheciate.

Substrate #

Corticolous, lignicolous, saxicolous

Physconia americana

Mon, 01 Jan 0001 00:00:00 +0000

Physconia americana #

Taxon #

Physconia americana

Organization #

Physciaceae

Identification #

Physconia americana can be recognized by the conspicuous pruina characteristic of the genus paired with the attractively-lobulate apothecia. The flattened green, brownish, or grayish lobes are similar to many other species within the Physciaceae but it is the only species with apothecia which themselves have lobes growing from the rims.

Substrate #

corticolous, saxicolous, bryocolous, muscicolous

Physconia enteroxantha

Mon, 01 Jan 0001 00:00:00 +0000

Physconia enteroxantha #

Taxon #

Physconia enteroxantha

Organization #

Physciaceae, Frost Lichens

Identification #

Physconia enteroxantha shares the grayish, greenish, tan, or brownish color and pruinose lobes characteristic of the frost lichens. It can be readily identified by having a yellowish medulla paired with yellowish-green, granular, marginal soredia.

Substrate #

corticolous, lignicolous, saxicolous (Brodo et al. 2001)

Chemical Tests #

cortex: K-, C-, KC-, Pd-; medulla: K+ yellow, C-, KC+ yellow to orange, Pd-; soralia: K- or K+ yellow, KC- or KC+ yellow to orange (CLH)