This species has shoots that are 0.5 to 3 mm wide with leaves 1 to 2 mm wide and 0.5 to 1 mm long. It is brownish green or yellowish green and has 3 lobed leaves and underleaves. Microscopic examination is required to separate it reliably from B. atlantica and B. hatcheri.

Open, upland habitats on mossy boulders or turf on north facing slopes.

All year.

Locally abundant.

Not known.