aalloihins

Aalloihins are a fictional taxon used in speculative biology and science fiction to describe a group of photosynthetic, multicellular aquatic organisms. In common worldbuilding depictions they form translucent thalli or filamentous mats that cling to submerged substrates, ranging from a few centimeters to several decimeters in extent. The cells possess chlorophyll-like pigments and a unique set of accessory pigments that broaden light absorption, including near-infrared wavelengths, allowing survival in low-light or turbid waters. Some portray a bioluminescent element, producing soft illumination at night.

Taxonomy and biology: Within fictional schemes, aalloihins are eukaryotic and display modular, cell-to-filament organization. They reproduce primarily by fragmentation of mats and by releasing motile zoospores in favorable conditions. Their metabolism is typically described as photoautotrophic, sometimes with mixotrophic capabilities, siphoning inorganic nutrients from the water and leveraging symbiotic bacteria for nutrient cycling.

Habitat and ecology: Aalloihins are depicted in tranquil freshwater ecosystems, brackish lagoons, or subsurface aquatic worlds. They often form the base of a local food web, providing habitat for microfauna and interacting with methanotrophic or sulfur-oxidizing microbes. Their mats can influence sediment stability and water chemistry.

Origin and usage: The term is a coinage used by writers and in speculative biology primers to explore alternative biochemistries and ecological roles. There is no empirical evidence for real-world organisms by this name.