Description: Thallus fruticose, filamentous, loosely attached, erect to caespitose, rigid, without a main branch, usually with perpendicular, 0.2-0.5 mm thick branches, black at the base, often brownish black in terminal parts, with olive-grey to pale brown, often shiny apices, and with dark, often arcuate lateral spinules, esorediate. Pseudocyphellae sparse, fusiform, brown, level with thallus or slightly raised; medulla white, compact. Apothecia extremely rare (never observed in Italian material), zeorine, with a brown disc, to 3 mm across. Asci 8-spored, Lecanora-type. Ascospores 1-celled, hyaline, globose to broadly ellipsoid, 6-9 x 4-6 μm. Photobiont chlorococcoid. Spot tests: cortex and medulla K-, C-, KC-, P+ red. Chemistry: fumarprotocetraric acid.
Note: a mainly boreal-montane, circumpolar lichen found on mossy trunks of old, more or less isolated trees in mountain areas with frequent fog, sometimes on mossy rocks. The study of Boluda et al. (2019) revealed a strong mismatch between phenotypes and genotypes in Bryoria sect. Implexae, which brought to the reduction from 11 to 4 species. All European species (B. capillaris, B. chalybeiformis, B. implexa, B. lanestris, B. kuemmerleana, and B. subcana) should be considered as synonyms of B. fuscescens. Due to their chemical and morphological differences, I still provisionally maintain these taxa as separate species, although they should be best treated as chemical races or forms of B fuscescens.
Growth form: Fruticose filamentous
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly asexual, by thallus fragmentation
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)