Giant Keyhole Limpet

The Giant Keyhole Limpet is a large marine mollusk found along the rocky shores of the eastern Pacific Ocean, from Alaska down to Baja California. This species is known for its distinctive, conical, and slightly flattened shell, which can reach lengths of up to 8 inches. The shell is typically dark brown or black, often with radial ridges, and features a prominent hole at the apex of the shell, giving it its name. This hole is thought to help with water flow and ventilation.

The Giant Keyhole Limpet is a herbivore, feeding primarily on algae, especially kelp, which it scrapes off rocks using its rough, radula (a toothed, tongue-like organ). These limpets are often found in intertidal and subtidal zones, where they are typically anchored to rocks or other hard surfaces. In aquariums, they are usually fed algae or specially formulated food that mimics their natural diet.

This species is known for its ability to firmly attach itself to rocks using its muscular foot, which allows it to withstand strong waves and tidal surges. Despite its large size, the Giant Keyhole Limpet is relatively slow-moving and relies on its ability to blend into the rocky substrate to avoid predators.

Giant Keyhole Limpets have a lifespan of 10 to 20 years in the wild, although their average lifespan is around 15 years. These limpets are not currently considered at risk, and their populations remain stable across their range, though they can be impacted by habitat destruction and over-harvesting in some areas.

Fun Facts:
The "keyhole" in the shell of the Giant Keyhole Limpet allows water to flow in and out of the shell, helping the animal breathe and expel waste.

Giant Keyhole Limpets are important grazers in kelp forests, helping to control algae growth and maintain the balance of these vital ecosystems.

The species has a unique defense mechanism: when threatened, it can quickly retreat into its shell and close off the hole to protect itself from predators.