Staurozoa
Staurozoa is a class of cnidarians within the phylum Cnidaria. They are commonly known as stalked jellyfish or polyp jellyfish. Staurozoans are distinguished from other jellyfish by their lack of a medusa stage, instead existing solely as a polyp, resembling a small, vase-shaped, or star-shaped organism attached to a substrate. They typically live in marine environments, mainly cold waters, attached to seaweed, rocks, or other submerged surfaces. These unique jellyfish-like animals are sessile, meaning they are permanently fixed to a substrate. Their bodies are designed for capturing prey, with tentacles surrounding the mouth, which is located on the top of the polyp.
Common Names
Staurozoa are known by several common names, including:
- Stalked jellyfish
- Polyp jellyfish
- Lucernarians
- Haliclystus
Characteristics
Staurozoans possess a number of distinctive characteristics that set them apart from other cnidarians. These include:
- Sessile Lifestyle: Unlike most jellyfish, staurozoans remain permanently attached to a substrate, often in shallow water. This sessile nature allows them to filter feed and capture prey.
- Polyp Morphology: Staurozoans exist only in the polyp stage, lacking the free-swimming medusa stage common in other cnidarians. Their bodies are typically small and vase-shaped or star-shaped.
- Tentacles: Staurozoans have tentacles surrounding their mouths, which are used to capture prey. These tentacles can be long and thin, allowing them to reach out and capture food.
- Reproduction: Staurozoans reproduce both sexually and asexually. Sexual reproduction occurs through the release of sperm and eggs, while asexual reproduction occurs through budding.
Environments
Staurozoans are found in a variety of marine environments, primarily in cold waters. They are often found attached to seaweed, rocks, or other submerged surfaces, in shallow water. They are also found in deeper waters, up to 200 meters deep.
References
For further information on Staurozoa, refer to the following reliable sources: