Mediaster

Characteristics

Members of the genus Mediaster are characterized by their five-rayed, flattened bodies. They have a distinctive, star-shaped outline with short, thick arms. The aboral (upper) surface is usually covered in small, granular ossicles (bony plates), while the oral (lower) surface features a central mouth surrounded by five ambulacral grooves. These grooves contain tube feet, which are used for locomotion and feeding.

Environment and Distribution

Mediaster species are distributed throughout the world's oceans. They are found in a variety of marine habitats, including:

• Shallow intertidal zones
• Rocky reefs
• Sandy bottoms
• Deep-sea environments

These sea stars are generally found in areas with moderate to strong currents, where they can easily obtain food and avoid predation. They are often found in association with various benthic organisms, including algae, sponges, and other invertebrates.

Feeding

Mediaster sea stars are carnivores and scavengers. They feed primarily on small invertebrates, such as crustaceans, mollusks, and worms. They use their tube feet to capture prey and bring it to their mouths.

Reproduction

Mediaster species reproduce sexually, releasing sperm and eggs into the water column. Fertilization occurs externally, and the resulting larvae develop into juvenile sea stars. Some species are known to brood their eggs, protecting them until they hatch.

References

For further information on Mediaster sea stars, please refer to the following sources:

• World Register of Marine Species (WoRMS)
• PubMed
• ResearchGate