Flower hat jelly

Olindias formosus · The flower hat jelly is a fluorescent hydromedusa that lives in the northwestern Pacific off Japan and South Korea's Jeju Island.

Also called Flower hat jellyfish.

Flower hat jelly
Photo: Fred Hsu (Wikipedia:User:Fredhsu on en.wikipedia), CC BY-SA 3.0
Flower hat jelly
Photo: Σ64, CC BY 4.0
Flower hat jelly
Photo: Chris Favero from USA, CC BY-SA 2.0

Taxonomy

KingdomAnimalia
PhylumCnidaria
ClassHydrozoa
OrderLimnomedusae
FamilyOlindiidae
GenusOlindias
SpeciesOlindias formosus

Where it lives

North-west Pacific off central and southern Japan and South Korea's Jeju Island.

Fun facts

  • Although it looks like a jellyfish, the flower hat jelly belongs to a different class, Hydrozoa, rather than the true jellyfish class.
  • By day it rests on the bottom among rocks or algae, then floats up at night to hunt small fish.
  • Its tentacles may look random, but they are arranged in a pattern matching an optimal hashing algorithm called Fibonacci hashing.
  • Its glowing fluorescent proteins help it catch food by drawing prey toward the unusual light.

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