What has endoskeleton and radial symmetry?

Organisms that possess an endoskeleton and exhibit radial symmetry are primarily found in the phylum Echinodermata, which includes sea stars, sea urchins, and sea cucumbers. These animals have an internal skeleton made of calcareous plates and typically display a body plan that is symmetrical around a central axis. This unique combination allows them to thrive in marine environments, where their radial symmetry aids in movement and feeding.