Filumuna

Filumuna is a fictional taxon used in speculative biology and science fiction to illustrate theoretical models of early animal diversification. It is not an officially recognized group, and no fossil or genetic evidence supports its existence. The name combines Latin roots filum, meaning thread, and una, meaning one, alluding to its proposed threadlike body form.

In most depictions, Filumuna comprises slender, flexible filaments or tube-like bodies ranging from a few millimeters to several centimeters, lacking complex tissues or organs. Some versions describe a simple, porous body with a basal holdfast, enabling slow, sessile movement or attachment. Reproduction is often depicted as fragmentation, budding, or spore-like propagules, resulting in rapid local colonization.

Ecological role. Filumuna is usually placed in soft-substrate habitats such as shallow marine or freshwater bottoms. Feeding is portrayed as filter-feeding or detritivory through a primitive canal system or choanocyte-like cells, drawing in suspended particles from the water column.

Conceptual use. The term is commonly employed in education and world-building to discuss phylogenetic uncertainty, the challenges of interpreting the fossil record, and the distinction between hypothesis-driven and evidence-based classifications. It is not used in formal systematics; any real taxonomy would require rigorous data meeting the standards of relevant nomenclatural codes.