Fissurella nubecula, commonly referred to as the Keyhole Limpet, is a marine gastropod mollusk belonging to the family Fissurellidae. This species is notable for its distinct shell structure, which features a keyhole or slit-like opening at the top, allowing for water circulation and respiration.

In the Comunidad Valenciana, this species can often be found along rocky shorelines and tidal pools, where it adheres to hard surfaces. It plays a vital role in the local ecosystem as both a grazer of algae and a food source for various predators.

• Shell Description: The shell of Fissurella nubecula is conical with a rough and ribbed texture. It typically exhibits a coloration that ranges from grayish to brown, sometimes with distinctive patterns or markings.
• Size: This limpet species can grow to a size of approximately 3 to 5 centimeters in diameter.
• Habitat: Prefers intertidal zones and shallow subtidal areas where it can attach to rocky substrates.
• Diet: Primarily feeds on microalgae, using its radula to scrape food from the substrate.
• Ecological Role: Acts as both a grazer, maintaining algae populations, and as prey for various species of birds, fish, and other marine animals.

Overall, Fissurella nubecula is an integral species within the coastal ecosystem of the Comunidad Valenciana, contributing to both the biological diversity and the ecological balance of the region.