Edwardsia
Edwardsia is a genus of burrowing sea anemones, commonly referred to as “tube anemones,” belonging to the family Edwardsiidae. These anemones are characterized by their slender, elongated bodies and their ability to burrow into soft sediment. The genus comprises over 100 species, many of which are found in intertidal and subtidal habitats worldwide.
Characteristics
Members of the genus Edwardsia exhibit several distinctive traits. They typically possess a cylindrical body with a distinct oral disc at the top, surrounded by tentacles. The tentacles are often arranged in multiple whorls, and their number varies depending on the species. Unlike most sea anemones, Edwardsia anemones lack a pedal disc, the basal attachment structure found in other species. Instead, they possess a specialized structure called a "scapus" that is used for burrowing and anchoring within the sediment.
Environments
Edwardsia anemones are primarily found in soft-bottom environments, such as sand, mud, and gravel. They are commonly observed in intertidal zones, where they can tolerate exposure to air during low tide. Some species, however, inhabit deeper water, reaching depths of hundreds of meters. They typically burrow into the sediment, leaving only their tentacles and oral disc exposed to capture prey.
Common Names
Edwardsia anemones are often referred to as "tube anemones" due to their cylindrical bodies and their tendency to burrow into tubes or burrows created by other organisms. Other common names include "burrowing anemones" and "sand anemones."