Description: Thallus foliose to subfruticose, loosely attached, forming irregular rosettes or dense tufts to 5 cm across. Lobes 1-5 mm wide, dorsiventral, slightly canaliculate or terete, ascending to erect. Upper surface bright yellow in open habitats to greenish yellow in shaded habitats; lower surface pale yellow to tan or whitish, more or less veined, with pale, squarrose rhizines. Upper and lower cortex paraplectenchymatous; medulla yellow, very loose. Apothecia frequent especially in epiphytic forms, lecanorine, submarginal to almost laminal, 2-6 mm across, with a brown to brown- black disc and a smooth, yellow thalline margin. Asci 8-spored, broadly clavate, Lecanora-type. Ascospores 1-celled, hyaline, broadly ellipsoid to subglobose, 5-6 x c. 5 μm. Pycnidia frequent, black, marginal to laminal, immersed or on short black projections. Conidia bottle-shaped, 6-8 x 1-2 μm. Photobiont chlorococcoid. Spot tests: cortex K-, C-, KC+ yellow, P-; medulla K-, C-, KC-, P-, UV+ blackish red. Chemistry: cortex with usnic acid; cortex and medulla with vulpinic and pinastric acids.
Note: this mainly subarctic-subalpine to boreal-montane species is found on calciferous mineral soil in dry Alpine grasslands and on wind-exposed ridges, more rarely on the twigs of shrubs. It is included as “Regionally Exctinct” in the Italian red list of epiphytic lichens (Nascimbene & al. 2013c), but this referred only to the epiphytic forms formerly treated as V. juniperinus.
Growth form: Foliose, broad lobed
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly asexual, by thallus fragmentation