Holothuria
Holothuria is a genus of sea cucumbers belonging to the family Holothuriidae. These marine invertebrates are commonly known as sea cucumbers, and they are found in a variety of habitats, including coral reefs, sandy bottoms, and deep sea trenches. They are characterized by their elongated, cylindrical body shape, which is often covered in spines or bumps. Sea cucumbers play an important role in marine ecosystems, as they help to break down organic matter and improve water quality.
Common Names
Members of the genus Holothuria are commonly referred to as sea cucumbers. Depending on the species, they may also be known as:
- Sea slugs
- Sea potatoes
- Trepang
- Bêche-de-mer
Characteristics
Holothuria species are typically characterized by the following features:
- Elongated, cylindrical body: Their bodies are often described as being sausage-shaped or cucumber-like.
- Soft, leathery skin: Their skin is typically covered in a thin layer of mucus that helps protect them from predators and parasites.
- Five rows of tube feet: These are used for locomotion and feeding.
- Mouth located at one end of the body: The mouth is surrounded by a ring of tentacles that are used to capture food.
- Anus located at the other end of the body: This is where waste is expelled.
- Water vascular system: This system is used for movement, feeding, and respiration.
- Cuvierian tubules: These are defensive organs that can be ejected from the anus to deter predators.
Environments
Sea cucumbers in the genus Holothuria are found in a wide range of marine environments, including:
- Coral reefs: Many species are found living among the coral colonies.
- Sandy bottoms: They burrow into the sand and feed on the organic matter that they find there.
- Seagrass beds: Some species are found grazing on the seagrass.
- Deep sea trenches: These are some of the deepest and most hostile environments on Earth, yet some sea cucumbers still thrive there.
References
WoRMS - World Register of Marine Species