Sea Urchins
Sea Urchins
Euechinoidea
Animalia
COMMON

Stats

Lifespan
Decades
Size
Small
Diet
Herbivore
Activity
Nocturnal
Social
Solitary
Biome
Ocean
Range
Worldwide oceans
Movement
Crawling
Breeding
Egg-laying
Defense
Spines
Status
Common

About

The subclass holding almost every living sea urchin — the spiny, globe-shaped grazers that creep over reefs and rocks on tube feet, scraping algae with a five-toothed jaw called Aristotle's lantern. It also includes their flattened relatives, the sand dollars and heart urchins that burrow through seafloor sediment.

Life cycle

  1. 1.
    juvenile
    A juvenile urchin settles onto the seafloor and begins grazing algae with its tiny test and spines.
  2. 2.
    adult
    Fully grown, with adult test size and full spines.

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Taxonomy

Kingdom
Animalia
Phylum
Echinodermata
Class
Echinoidea