Cnidaria · cnidarians

Moon jelly

Aurelia aurita

Ulmaridae · moon jelliesIUCN: Not evaluated
Moon jelly
Photo: Luc Viatour · CC BY-SA 3.0 · Wikimedia Commons · resized

A translucent jelly recognized by the four horseshoe-shaped gonads in its bell.

Fun factMoon jellies can bloom in such numbers that they clog power plant cooling intakes.

Waters
Worldwide, Northeast US
Depth zone
Coastal shallows & estuaries, Continental shelf
Diet
Zooplankton
Size
Bell up to 40 cm

Classification

Cnidaria › Scyphozoa › Semaeostomeae › Ulmaridae

  1. Kingdom Animalia animals
    • Many-celled organisms that eat other living things for energy (heterotrophs)
    • Cells have no cell walls
    • Most can move at some stage of life
  2. Phylum Cnidaria cnidarians
    • Radially symmetric bodies with one opening that is both mouth and anus
    • Stinging cells (cnidocytes) fire tiny harpoons (nematocysts)
    • Two body forms: an attached polyp and a swimming bell (medusa)
  3. Class Scyphozoa true jellyfish
    • True jellyfish: the swimming bell (medusa) is the main life stage
    • Small polyps bud off baby jellies by splitting in stacks (strobilation)
    • Bell edge has sense organs (rhopalia) in notches
  4. Order Semaeostomeae flag-mouth jellyfish
    • Jellies with four long, frilly oral arms hanging from the mouth
    • Tentacles hang from the edge of the bell
  5. Family Ulmaridae moon jellies
    • Moon jellies and relatives with a flat, saucer-shaped bell
    • Short, fine tentacles around the bell edge
  6. Genus Aurelia
    • Species in the same genus are very close relatives and often look alike.
  7. Species Aurelia aurita Moon jelly

Closest relatives in the guide