One primitive feature of the coelenterates is the possession of

The primitive feature of the coelenterates is the possession of radial symmetry. Radial symmetry means that the body of the organism is arranged in a circular or radial pattern around a central axis. This is different from bilateral symmetry where the body is divided into two mirror-image halves. Radial symmetry is considered primitive because it is found in many of the earliest forms of animals and is a less complex form of symmetry. The possession of radial symmetry in coelenterates allows for equal access to the environment in all directions and also enables them to capture prey from any direction.