Most cnidarians are considered carnivores because of their ability to actually catch food with their stinging cells called nematocysts. Class Octocorallia is not well represented in the fossil record because of its poorly calcified skeletons. The first part of the lab introduces you to the taxonomy of the Cnidarians and their geologic ranges. Geologically the anthozoans are the most important of the cnidarians because their polyps often produce calcitized skeletons that are readily preserved as fossils. They can be either solitary or colonial.
Anthozoans differ from other Cnidaria in that they have no medusoid stage.
They are exclusively marine and occur at various depths from shallow to deep water. The exclusively colonial Tabulate corals occur only in the Paleozoic. Each of the corallites typically have a tabula that serve as the floor for the polyp. Septa in tabulate corals are either absent or inconspicuous. The Paleozoic rugosan corals can be either solitary or colonial.