<em>Collema furfuraceum</em> is a species belonging to the genus <em>Collema</em>, a group of cyanolichens that form symbiotic associations between fungi and cyanobacteria. This species is classified as Extinct, representing one of the more severe conservation outcomes for organisms in its taxonomic group. Historical records indicate its presence across several European nations, including Denmark, Norway, Portugal, and Sweden, suggesting it once occupied a reasonably broad range within the continent. The habitats it occupied were consistent with those favored by cyanolichens, typically moist, shaded substrates such as bark, rock faces, or soil in areas with high humidity and low disturbance. Dietary ecology, as applicable to a lichen, involves photosynthetic and nitrogen-fixing activity carried out by its cyanobacterial partner rather than active foraging. Biological traits of this species remain poorly documented in the scientific literature. The extinction of <em>Collema furfuraceum</em> underscores the vulnerability of lichen-forming organisms to habitat degradation, changes in air quality, and loss of old-growth forest environments.