Heteractidae
Heteractidae is a family of sea stars belonging to the order Paxillosida. These are commonly known as “burrowing sea stars” due to their unique adaptations for subterranean life. They are characterized by their flattened, disc-shaped bodies and relatively short, blunt arms. Most species lack the typical, well-defined arms of other sea stars, with their bodies appearing more rounded and compact. This body shape, combined with their robust, shovel-like spines and strong tube feet, allows them to efficiently burrow into soft sediment.
Common Names
Members of the Heteractidae family are often called "burrowing sea stars," but other common names include:
- Sand stars
- Shovel stars
- Flat sea stars
Characteristics
Heteractidae sea stars possess several distinctive features that differentiate them from other sea star families:
- Flattened, disc-shaped body: This body plan is highly specialized for burrowing and allows them to move effectively through sediment.
- Short, blunt arms: Unlike the typical, long arms of other sea stars, Heteractidae species have reduced arms that are not readily discernible.
- Robust, shovel-like spines: These spines assist in burrowing and provide protection.
- Strong tube feet: Their powerful tube feet aid in locomotion and burrowing.
- Reduced or absent pedicellariae: Pedicellariae are small, pincer-like structures found on the surface of many sea stars. Heteractidae species typically lack these structures or have only a few.
Environments
Heteractidae sea stars are primarily found in marine environments with soft sediments, such as sand, mud, and gravel. They are commonly found in intertidal zones, shallow water, and even deep-sea environments.
References
For more information on Heteractidae, please refer to these reliable sources: