The lichen is found in Eastern Siberia, the Russian Far East as well as in adjacent territories of north-east China, and in South Korea.

The lichen is known to occur in a few localities near in Yakutia's Indigirka river valley, where it grows on steep, sun-exposed boulder faces.

[3] Boreoplaca ultrafrigida is a lichen characterised by a squamiform (scale-like) thallus, which grows in irregular rosette patterns, often expanding along cracks in the substrate.

The upper surface of the thallus is medium brown, smooth to slightly wrinkled or cracked, and lacks any powdery coating (pruina).

[1] The medulla, the internal tissue of the thallus, is loosely organised with thin-walled hyphae, similar to those in the upper cortex but lacking crystals and not reacting to standard chemical tests (PD−, K−, C−).

The excipulum, or outer edge of the apothecia, is annulate (ring-like) and composed of radiating hyphae, with an olivaceous-black rim that turns greener in potassium hydroxide.

The paraphyses (sterile filaments) are weakly conglutinated (stuck together), unbranched or minimally branched, and thin-walled, with green granules incrusting their surface.

[1] The lichen also has pycnidia, which are small, flask-shaped structures embedded in the thallus that produce asexual spores called conidia.

[1] Beyond its type locality in Yakutia, B. ultrafrigida has been found in several other regions of Russia, including Buryatia, Magadan Oblast, and Primorsky Krai.