Coastelor

Coastelor is a fictional marine invertebrate described for the purposes of illustrating coastal ecology in this article. It is presented as a small, sessile organism that attaches to rocky substrates along temperate coastlines.

Adults of Coastelor are 1–3 cm long, oval or shield-shaped, with a calcareous outer plate and a soft, translucent mantle. Color varies from dull gray-brown to iridescent blue-green, depending on light and attached microalgae. The body bears several feathery appendages used for feeding and gas exchange.

In the fictional ecosystem, Coastelor inhabits rocky shores and tide pools within a coastal archipelago called the Solis Archipelago. It prefers shaded crevices and wave-exposed ledges from the intertidal to shallow subtidal zones, down to about 15 meters.

Coastelor is a filter feeder, drawing water through openings in the mantle and trapping detritus and plankton with ciliary structures. It may host surface-dwelling microalgae, which provide nutrition in exchange for shelter. Reproduction is broadcast spawning in spring; larvae are free-swimming for several weeks before settling.

As a fictional organism, Coastelor has no real conservation status. In educational contexts, it serves as a model for studying how coastal organisms respond to pollution, sedimentation, and habitat disturbance. In some stories it features in local folklore as a symbol of resilience on the shoreline.