[1][2] They are distinguished from other jellyfish by the presence of a deep groove running around the umbrella, giving them the crown shape from which they take their name.

Many of the species in the order inhabit deep sea environments.

[3] Crown jellyfish are able to make light through bioluminescence.

When they are attacked, crown jellyfish are able to startle, mislead, and distract their predators with the light that they produce.

[4] As of 2016[update], 53 recognized extant species were in the order Coronatae, spread throughout 12 genera.