Stats

Lifespan: 10-30 yrs
Size: Small
Diet: Omnivore
Activity: Nocturnal
Social: Solitary
Biome: Marine benthic
Range: Worldwide
Movement: Walking
Breeding: Egg-laying
Defense: Spines
Status: Common

About

A spiny, globe-shaped echinoderm that grazes algae from rocky reefs using a five-toothed jaw apparatus called Aristotle's lantern. Its hundreds of movable spines pivot on ball-and-socket joints and are reinforced with magnesium-rich calcite for extra hardness.

Life cycle

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

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Taxonomy

Kingdom: Animalia
Phylum: Echinodermata
Class: Echinoidea