Calycophorae

The Abylidae are a family of marine invertebrates in the order Siphonophorae. They are colonial, but the colonies can superficially resemble jellyfish; although they appear to be a single organism, each specimen is actually a colony of Siphonophora.

Prayidae is a family of marine invertebrates in the order Siphonophorae. They are colonial, and the colonies can superficially resemble jellyfish; although they appear to be a single organism, each specimen is actually a colony of Siphonophora.

Clausophyidae is a family of cnidarians belonging to the order Siphonophorae.

The Diphyidae are a family of siphonophores. These are colonial siphonophores with two nectophores (swimming bells) arranged one behind the other. The front one includes a somatocyst (extension of the gastrovascular system), while the hind one does not. The somatocyst often contains an oil droplet for buoyancy control. A nectosac (central cavity with muscular walls) in each nectophore allows the organism to swim efficiently.

Hippopodiidae is a family of cnidarians belonging to the order Siphonophorae.

Sphaeronectidae is a family of cnidarians belonging to the order Siphonophorae.