Granite Limpet

Cymbula granatina

Cymbula granatina is a species of true limpet characterized by its shell size, which ranges from 50 mm to 90 mm. This marine gastropod mollusc is commonly found along the upper shore of the Atlantic Ocean, particularly off the coasts of South Africa and Angola, within the cool temperate biogeographical region of Benguela. It typically inhabits rocky substrates where it can adhere tightly to the surface, making it a familiar sight for divers exploring these areas. Feeding primarily on various types of algae, the granite limpet is a herbivore that does not defend a territory. Instead, it grazes on algae using its toothed radula when submerged. The species exhibits a high growth rate and reproductive output, with larvae that develop into planktonic forms before settling on the shore. After about two years, the juveniles begin to migrate to higher areas on the shore, showcasing a notable homing ability as they return to the same spot when the tide recedes. Encounters with granite limpets during dives can be quite common, as they are one of the prevalent limpets on the foreshore. Their behavior of tightly adhering to rocks makes them less mobile when out of water, but they become active grazers when the tide covers them. Conservation status for this species is currently listed as Not Evaluated, indicating a lack of comprehensive assessment regarding its population dynamics.