Cnidaria: Subclass Zoantharia
Subclass Zoantharia
The subclass Zoantharia includes both solitary and colonial forms, in which the polyp has more than eight tentacles. The solitary sea anemones belong here, in the order Actiniaria, characterized by the lack of a skeleton. The stony corals so important in forming coral reefs belong to the order Madreporaria; they are especially characterized by their calcium carbonate exoskeleton, marked by many cups for the polyps, each of which contains stony septa dividing the gastrovascular cavity into compartments. The shape of coral skeletons depends on the pattern of growth of the colony. For example, in brain corals the polyps are arranged linearly; in the eyed coral (
Sections in this article:
- Introduction
- Subclass Zoantharia
- Subclass Alcyonaria
- Class Anthozoa
- Class Scyphozoa
- Class Hydrozoa
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