1. Echinoderms are invertebrates.
- Members of phylum Echinodermata which came from the Greek word “spiny skin”.
- There are about 7000 species of these fascinating wonders of the sea.
- Starfish, brittle stars, sea lilies, sea urchins and sea cucumbers are example of echinoderms.
2. Echinoderms possess specialized structure to protect themselves.
- Like humans, echinoderms’ epidermis also acts as its first line of defense against potential threat.
- There are three parts of the echinoderms’ lateral grooves namely the ampulla podia and sucker.
- Its ossicles, that makes up their skeletal system is embedded on the outer layer.
- Some echinoderms have their toxic spines like pincer-like structures that serve as its defense mechanism.
- Adult echinoderms have distinct radial (or bi-radial in larval forms) symmetrical body divided into multiple sections with hundreds of little sucker-like tube feet (or tentacles) under its arms which all comes with set of organs and a mouth at the center.
- They are also able to undergo camouflage to keep away from predators
3. Echinoderms are capable of regeneration.
- They have the remarkable power to re-grow lost body parts, amazingly even internal organs.
- Most reproduce sexually where eggs and sperm are laid and fertilized to produce planktonic larvae.
4. Echinoderms use water as their blood.
- It serves as the vascular system for oxygenation of its body and vital organs.
- Water is drawn into its feet which enable them to expand its body to move, feed on substrates, attach to surfaces and grasp to its prey.
- Pumps water through madreporite (serves as a sieve plate) to filter and fill its arms/feet with water.
- They have simple gills (located in its tube feet) intended for respiration.
5. Echinoderms are predators, scavengers and feeders.
- Their favorite prey is shellfish (bivalve) such as oyster or clams (they don’t actually eat the shell but what is inside), algae and non-insect anthropods.
- Its suction capacity is quite strong that it can manage to open the shell while outstretching its arms/feet.
- They have the ability to thrust its stomach and making use of the digestive juices to dissolve its prey for a meal.
6.Echinoderms are benthic marine critters.
- They commonly thrive on reefs and shores.
- There’s no way to find them on lands and fresh water.
- It will burst if you’ll try to put sea cucumber in fresh water.
7. Echinoderms are of ecological importance.
- They are oxygen provider under the sea (eg, sea cucumbers) and a habitat for other invertebrates like worms and snails.
- They are important in aquatic food web as they serve as the diet of some aquatic animals (eg. sea otter).
- They keep marine ecosystem overrun by seaweeds and prevent growth of algae (starfish) on coral reefs because they feed on them.
8. Echinoderms are brainless.
- Their arms are sensitive to varying degrees of light and chemicals to direct them in their verge of survival.
9. Echinoderms are edible.
- Some species are source of food such as the sea urchins and sea cucumber.
- Echinoculture is the commercial fishing and cultivation of echinoderms.
- Some countries like Japan and France considered it delicacies (such as using sea urchin roe for making sushi).
10. Echinoderms play a major part in scientific research.
- Biologically active compounds are found on some echinoderms mainly sea urchins and sea cucumbers.
- Discovery of these compounds had contributed a lot in biomedical field through production of essential medicines for human.
- Its potency is tested and known to have an effective antiviral and antimicrobial property.