Common name: Acorn Barnacles

Tetraclita is a genus of acorn barnacles that are commonly found in the intertidal zones of rocky shores. They are sessile crustaceans with a distinctive conical shape and are known for their hard calcareous plates that protect them from predators and desiccation. In reef aquariums, they can add a touch of natural diversity and are often introduced inadvertently on live rock. They are filter feeders, requiring minimal care, but should be monitored to ensure they do not overpopulate or interfere with other sessile invertebrates.