#actinacanth
- Actinacanth — A zoological term used to describe an organism, an anatomical structure, or a skeletal element provided with spines, spicules, or sharp extensions arranged in a radiating manner. In the context of paleontology and aquatic taxonomy, it specifically describes the morphology of certain radiolarians, sponges, or ancient marine fauna whose rigid support elements emerge from a common center in the shape of stinging rays.