Arctomia fascicularis

Gabura fascicularis is a species of jelly lichen in the family Arctomiaceae. It is widely distributed, found across parts of Europe, North Africa, Asia, Australia, and New Zealand. Originally described by Carl Linnaeus in 1767, this small cushion-forming lichen grows primarily on the bark of mature broad-leaved trees such as elm and ash, preferring moist, shaded woodland habitats.

The species has a distinctive gelatinous texture when wet and contains cyanobacteria that allow it to fix nitrogen from the atmosphere. Once more widespread, G. fascicularis has declined significantly in many regions due to the loss of old-growth trees and environmental pressures like acid rain, leading to its classification as a near-threatened species in Britain.

Molecular studies have revealed that the...

Occupies temperate montane forests with dense understory vegetation between 800-2,200m elevation, particularly favoring areas with high humidity and stable temperature regimes. Requires specific microhabitat conditions including fallen logs, moss-covered rocks, and areas with consistent moisture levels.