Styela
Styela is a genus of tunicates, commonly known as sea squirts, that are found in marine environments worldwide. These sessile filter feeders are characterized by their sac-like bodies and two siphons, one for inhaling water and the other for expelling it. They are typically found attached to hard substrates, such as rocks, piers, and ship hulls. Styela species are important members of marine ecosystems, contributing to nutrient cycling and providing food for other organisms.
Common Names
Common names for Styela species include:
- Sea squirts
- Sea potatoes
- Tunicates
Characteristics
Styela species are characterized by the following features:
- Sac-like body: Their bodies are typically oval or cylindrical in shape, with a tough, leathery outer layer called a tunic.
- Two siphons: They have two openings called siphons, one for inhaling water and the other for expelling it. The incurrent siphon is usually located at the top of the body, while the excurrent siphon is located on the side.
- Filter feeders: They feed by filtering small particles of food from the water, such as phytoplankton and zooplankton.
- Sessile: They are attached to hard substrates and are unable to move freely.
Environments
Styela species are found in a variety of marine environments, including:
- Intertidal zones: They can tolerate periods of exposure to air during low tide.
- Subtidal zones: They are also common in deeper waters, often attached to rocks and piers.
- Estuaries: Some Styela species are adapted to live in brackish water environments.