Description: Thallus fruticose, tufted in basal parts, pendent in the apical parts, attached by a basal holdfast, to 20 cm long, pale grey to pale brown, usually with a pink hue, rarely dark brown in sun-exposed morphs, isotomic-dichotomously branching with obtuse (towards the base) to acute angles, the main branches mostly terete, often with sparse to abundant lateral spinules. Soralia sparse to usually abundant, small, tuberculate, white to greenish white, with farinose soredia. Pseudocyphellae sparse, inconspicuous, or usually absent; medulla white, compact. Apothecia extremely rare, zeorine, with a brown disc, to 2 mm across. Asci 8-spored, Lecanora-type. Ascospores 1-celled, hyaline, subglobose to ellipsoid, 5-7 x 3-4 μm. Photobiont chlorococcoid. Spot tests: cortex and medulla K+ yellow, C+ red, KC+red, P+ yellow; soralia P+ red. Chemistry: alectorialic and barbatolic acids, sometimes atranorin; fumarprotocetraric acid in soralia.
Note: a boreal-montane, circumpolar, shade-tolerant species of mixed upper montane to oroboreal forests, mostly on low, dead twigs and branches of conifers.
Growth form: Fruticose filamentous
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly asexual, by soredia, or soredia-like structures (e.g. blastidia)