Lédús

Lédús is a fictional genus of bioluminescent, lichen-like organisms used in speculative biology and worldbuilding. In the imagined ecosystems where it appears, members of Lédús form crustose patches on exposed basalt and granite, typically in shaded, humid microhabitats such as forested rock faces and cliff overhangs.

Description: The thallus of Lédús lichens ranges from a few millimeters to several centimeters in diameter, with a surface that appears pale gray or green and emits a soft blue-green glow at dusk. The glow is produced by a luciferin-luciferase-like system associated with a symbiotic photobiont, and luminescence is stronger in damp conditions.

Ecology and life cycle: Lédús grows on mineral substrates where it contributes to microhabitat formation and rock weathering. It reproduces asexually via soredia and sexually through apothecia; dispersal is aided by wind and water spray. In the fictional food webs, Lédús serves as a minor resource for invertebrates and foraging nocturnal predators.

Taxonomy and species: The genus comprises several described species in the worldbuilding corpus, including Lédús luminis, Lédús noctis, and Lédús basaltis. These species differ in thallus texture, luminescence patterns, and preferred substrate. The taxonomy is not based on real-world specimens.

Etymology and use: The name Lédús derives from a fictional Proto-Lédan root for light, with a Latinized suffix. In the narrative world, Lédús is cited in biogeography texts and sometimes referenced in cultural lore as a natural light source.