Echinodermata
The phylum Echinodermata includes starfish, sea urchins, brittle stars and sea cucumbers. All echinoderms live in the sea, and usually on the sea bed, where they creep around on suckered tube feet that look like hundreds of tiny legs. Only a few of them can swim or float. They mostly have fivefold symmetry, with arms or rays in multiples of five, and five teeth arranged in a circlet in their mouth.
They eat different things. Many starfish are predators and eat things like molluscs and barnacles. One even eats coral. Lots of starfish turn their stomachs out through their mouth and digest food outside their body. Crinoids, also called sea lilies, are filter feeders like Porifera; they suck seawater through themselves to extract food, while sea cucumbers (holothurians) scavenge for leftovers on the deep-sea bed. Sea urchins scrape algae from rocks to eat. They're called sea urchins because they're round and spiky like rolled-up hedgehogs - urchin is an old word for hedgehog.
Humans eat some echinoderms - sea cucumber is a delicacy, and sea urchin eggs (called roe or uni) are eaten raw in Japanese sushi, often on a small pad of seaweed-wrapped rice. Their colour ranges from brownish yellow to orange, with a texture like a firm, slightly grainy custard. The flavour is sweet and tangy, and rather like lobster.