Monotypic prehistoric cnidarian genera

Auroralumina (from Latin aurōra "dawn", lūmina "lights") is a genus of cnidarian from the Ediacaran of Charnwood Forest, comprising the single species Auroralumina attenboroughii. It is the earliest known crown-group cnidarian, and also the earliest known animal predator.

Haootia quadriformis is an extinct animal belonging to the Ediacaran biota. Estimated to be about 560 million years old, H. quadriformis is identified as a cnidarian polyp, and represents the earliest known evidence for muscle tissue in an animal. Discovered in 2008 from Newfoundland in eastern Canada, it was formally described in 2014. It is the first Ediacaran organism discovered to show fossils of muscle fibres. Structural examination of the muscles and morphology indicate that the animal is a cnidarian, though, which class H. quadriformis belongs to was undetermined until a 2024 study foun