Laminoiduns

Laminoiduns are a hypothetical clade of sessile marine invertebrates defined by a laminated exoskeleton composed of interlocking plates called laminae. The term laminoidun is used in speculative biology and worldbuilding to imagine a life form with a modular, sheet-like integument.

Morphology and physiology: Each laminoidun has a central body encased by a mosaic of calcified or chitinous laminae that can flex at the joints. A basal holdfast anchors the organism to rock, coral rubble, or other hard substrates. A feeding apparatus, often described as a crown of ciliated tentacles or a filter-facing aperture, enables suspension feeding in shallow, clear waters. Growth occurs through the accretion of additional laminae, expanding the surface area as the organism increases in size.

Ecology: Laminoiduns typically inhabit shallow coastal zones, lagoons, and reef flats. Their laminated armor provides habitat complexity for small invertebrates and encrusting algae and can contribute to substrate stabilization in intertidal to subtidal environments.

Reproduction and development: In speculative models, laminoiduns may reproduce sexually via external or internal fertilization and may also spread through asexual budding or fragmentation of the laminae, allowing rapid colony expansion under favorable conditions.

Taxonomic status and significance: Laminoiduns are not recognised in formal scientific taxonomy; they serve as a conceptual tool for exploring plate-based life forms, paleoenvironmental interpretation, and worldbuilding. They illustrate how laminated exoskeletons could influence ecology and fossil preservation.