[4] The genus Calicium features crustose lichens, which can be verrucose to granular in texture, or immersed in the substrate, and display a range of colours from grey to green-grey, pale yellow, or dark green.

The ascomata (fruiting bodies) are apothecial in nature, usually elevated on a long, distinct stalk with a spherical to lens-shaped head, though some may be directly attached (sessile).

[5] The asci (spore-bearing cells) are cylindrical to clavate (club-shaped) and develop individually from ascogenous hyphae with croziers, typically dissolving early in their lifespan.

[5] Calicium has a global presence, primarily found in cool to temperate regions, with only a few species known to occur in tropical areas.

Calicium prefers environments with low light, high humidity, and shelter, often thriving in old-growth forests, although some species can adapt to more open, sun-exposed locations.

[9] A fossil-calibrated phylogeny that includes this fossil suggests that the family Caliciaceae diversified from its most recent common ancestor 103–156 myr ago in the early Cretaceous.