Crown Jellyfish Fact Sheet

Common Name:

Crown Jellyfish, Cauliflower Jellyfish, Sea Jellies, True Jellyfish, Transparent Crown Jellyfish and Crown Sea Jelly

Scientific Name:

Cephea cephea

Wild Status:

Least Concern


Bays, lagoons, and estuaries


Pacific Ocean and Atlantic Ocean


Deep water in day and surface at night

Life Span:

6 months or less


Can have a bell that reaches 7.8 inches tall and a diameter of 6.7 inches

Cool Facts:

  • Crown Jellyfish are able to make light through bioluminescence.
  • If a Crown Jellyfish is attacked, they can startle and distract their predators with their light.
  • Crown Jellyfish eat zooplankton.
  • Crown Jellyfish are 95% water.
  • Crown Jellyfish have no heart, brain, blood or gills.
  • Crown Jellyfish are the most venomous of the jellyfish species and are not harmful to humans.
  • Crowned Jellyfish are a delicacy in Japan and China.
  • Crowned Jellyfish are carnivorous.


Crown Jellyfish swim with their umbrella shaped bell which looks like a crown and is bluish - purplish in color with eight arms extending from it. They have about 30 filaments with stinging cells nematocysts, sticking out from their bell. They are not harmful to humans and live up to 6 months.  Their diet consists of plankton, algae, shrimp and invertebrate eggs.  They are found in depths below 3000 feet where the temperature of the water is really cold. They move straight up and down from daytime to deep water and then at night to shallow. Crown jellyfish have different stages in reproduction.  They have a medusa (adult) stage and reproduce by releasing  eggs into the water which forms a planula. The planula stage can last for months or years and asexual reproduction occurs.

Taxonomic Breakdown:

Kingdom: Animalia Phylum: Cnidaria Class: Scyphozoa Order: Coronatae Family: Cephidae Species: Cephea cephea  

Conservation & Helping:

Scientists aren't sure if human impacts like overfishing, pollution and climate changes could affect the jellyfish population.

For Teachers and Educators


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