Ordovician – Recent
Anthozoa is an extant class of stationary intermediate-level epifaunal microcarnivores
Characteristics of the Class
- Unlike other cnidarians, anthozoans lack the medusa stage of development, instead releasing sperm and eggs that form a planula.
- Exclusively marine organisms
- Food includes small plankton and fish, captured by nemotocysts on the arm, which is pushed through the mouth and digested inside the body cavity.
- The name comes from the Greek words άνθος (ánthos; “flower”) and ζώα (zóa; “animals”), hence anthozoa = “flower animals”, a reference to the floral appearance of their perennial polyp stage
Treatise on Invertebrate Paleontology, Part F, 1 of 2 (1981):
- Exclusively polypoid, solitary, or colonial, mostly sedentary coelenterates. Oral end expanded as oral disc with centrally located mouth surrounded by peristome, around which are one or more rings of hollow tentacles. Stomodaeum strongly developed, leading from mouth into gastrovascular cavity biradially partitioned into compartments by complete or incomplete mesenteries, some of which bear endodermal gonads. Some groups characterized by horny or calcareous spicular endoskeleton or by calcareous exoskeleton. Exclusively marine.