Fissurellidae
Fissurellidae is a family of small to medium-sized marine gastropods that belong to the order Patellogastropoda, commonly known as limpets. The family is distinguished by its distinctive shell shape, which features a prominent, slit-like opening called a “fissure” at the apex. This fissure serves as an outlet for water and waste products. Fissurellids are often found clinging to rocky substrates in intertidal and subtidal zones, where they graze on algae and other microscopic organisms.
Common Names
Members of the Fissurellidae family are commonly referred to as "keyhole limpets" or "slit limpets" due to the presence of the characteristic fissure in their shells.
Characteristics
Fissurellids are typically characterized by the following features:
- Shell: Conical or dome-shaped with a distinct fissure at the apex. The shell is often ornamented with radial ribs or lines.
- Fissure: A slit-like opening at the apex of the shell, extending from the margin to the center. It is used for water circulation and waste expulsion.
- Foot: Large and muscular, used for locomotion and attachment to the substrate.
- Mantle: A fleshy fold that surrounds the body and secretes the shell.
- Radula: A ribbon-like structure in the mouth, covered in teeth, used for scraping algae and other food sources.
Environment
Fissurellids are primarily found in intertidal and subtidal zones, clinging to rocky substrates. They prefer environments with strong wave action and high levels of oxygenation. Their distribution is widespread, occurring in various regions around the world, including the Atlantic, Pacific, and Indian Oceans.