Sea urchins (/ˈɜːrtʃɪnz/), are typically spiny, globular animals, echinoderms in the class Echinoidea. About 950 species live on the seabed, inhabiting all oceans and depth zones from the intertidal to 5,000 metres (16,000 ft; 2,700 fathoms). Their tests (hard shells) are round and spiny, usually from 3 to 10 cm (1 to 4 in) across. Sea urchins move slowly, crawling with their tube feet, and sometimes pushing themselves with their spines. They feed primarily on algae but also eat slow-moving or sessile animals. Their predators include sea otters, starfish, wolf eels, triggerfish, and humans. Learn more about Sea urchin
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Sea Urchin Species Videos
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Common Name | Scientific Name | Conservation Status |
Black Longspine Sea Urchin (11 videos) | Diadema setosum | Not Available |
Collector Urchin (30 videos) | Tripneustes gratilla | Not Available |
Common Sea Urchin (7 videos) | Echinus esculentus | Not Available |
Double-spined Urchin (5 videos) | Echinothrix calamaris | Not Available |
Echinothrix Diadema (1 videos) | Echinothrix diadema | Not Available |
Flower Sea Urchin (26 videos) | Toxopneustes pileolus | Not Available |
Globe Sea Urchin (1 videos) | Mespilia globulus | Not Available |
Green Sea Urchin (11 videos) | Strongylocentrotus droebachiensis | Not Available |
Hearth Heart Urchin (2 videos) | Maretia planulata | Not Available |
Imperial Lance Urchin (1 videos) | Phyllacanthus imperialis | Not Available |
Long-spined Sea Urchin (10 videos) | Diadema antillarum | Not Available |
Magnificent Fire Urchin (20 videos) | Asthenosoma ijimai | Not Available |
Purple Sea Urchin (81 videos) | Arbacia punctulata | Not Available |
Radiant Fire Urchin (14 videos) | Astropyga radiata | Not Available |
Red Sea Urchin (12 videos) | Mesocentrotus franciscanus | Not Available |
Savigny's Longspine Sea Urchin (3 videos) | Diadema savignyi | Not Available |
Sea Egg (3 videos) | Tripneustes ventricosus | Not Available |
Slate Pencil Urchin (1 videos) | Phyllacanthus parvispinus | Not Available |
Slate-pencil Urchin (1 videos) | Heterocentrotus mamillatus | Not Available |
Spiny Sea Urchin (3 videos) | Centrostephanus rodgersii | Not Available |
Ten-lined Urchin (3 videos) | Eucidaris metularia | Not Available |
Variable Fire Urchin (38 videos) | Asthenosoma varium | Not Available |
Violet Sea Urchin (3 videos) | Sphaerechinus granularis | Not Available |