Usnea glabrata

Diane L. Haughland

Usnea glabrata (Ach.) Vain., 1915

Common name	Lustrous Beard	Code: USNEGLA
Field Characters	Fruticose, shrub-like chlorolichen. Thallus small (typically < 4 cm), erect and tufted with pale green, shiny divergent branches, though often appearing “dirty”. Secondary branches distinctly narrow at point of attachment giving a “sausage-like” impression. Papillae absent or sparse and inapparent. Soralia often conspicuous, larger than half branch diameter, deeply excavate to convex-globular. Isidia absent, apothecia rare.
Similar species	Usnea lapponica: has similar soredia but will not have narrowed branch attachment points and it has obvious papillae. Usnea cornuta: has similar branch attachments and cortex sheen and medulla type, but has typically minute soralia (often with isidia).
Ecology	Common epiphyte on trees in the boreal and foothills regions, occasionally in parkland forests. Seems to be most common in higher humidity forest stands including treed wetlands.
Chemistry	Cortex KC+ yellow, K- or K+ pale yellow, C-, UV- (usnic acid). Medulla PD+ red to orange, K- or K+ dingy brown, UV- (protocetraric and fumarprotocetraric acids), or PD+ yellow, K+ yellow to orange, UV- (salazinic, norstictic, ± stictic (trace), ± protocetraric (trace) acid).
Molecular support	Weak to moderate support at the species level. Species described as U. glabrata in Lucking et al. (2020) formed a supported monophyletic clade, but it is is unclear whether this group represents U. glabrata s.str. or another species.
Links	Alberta Biodiversity Browser Consortium of Lichen Herbaria Ways of Enlichenment Photo Gallery
Gallery