Long-spined sea urchin

Diadema antillarum · The long-spined sea urchin is a black, spiky sea urchin that lives on coral reefs in the tropical western Atlantic and Caribbean.

Also called Lime urchin.

Long-spined sea urchin
Photo: NOAA, Public domain
Long-spined sea urchin
Photo: Diego Delso, CC BY-SA 4.0
Long-spined sea urchin
Photo: Emőke Dénes, CC BY-SA 4.0

Taxonomy

KingdomAnimalia
PhylumEchinodermata
ClassEchinoidea
OrderDiadematoida
FamilyDiadematidae
GenusDiadema
SpeciesDiadema antillarum

Where it lives

Coral reefs of the Caribbean, Florida and the western Atlantic.

Fun facts

  • Most sea urchin spines are only 1–3 cm, but this urchin's spines are usually 10–12 cm long and can reach 30 cm in very large individuals.
  • By day it often tucks itself into a crevice so that only its spines can be seen.
  • This urchin is very sensitive to light and often picks its resting spot based on how much shade there is.
  • Urchins with a crevice home roam about one metre away at night to feed.

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Facts and taxonomy adapted from Wikipedia (CC BY-SA 4.0).