After fertilization, the corals release planula that are ready to settle. Subsequent development produces a tiny larva, known as a planula. The cycle begins with a planula larvae. Fertilized eggs develop into small ciliated larvae called planula. The zygote develops into a planktonic planula larva. The fertilized eggs hatch into planula larvae. All the polyps and jellyfish arising from a single planula are genetically identical clones. They produce gametes which, after fertilisation, develop into planula larvae. Some groups of Nemerteans also produce larvae that are very similar to the planula. The released eggs are fertilized, and the resulting zygote develops quickly into a multicellular "planula". Placozoa has been noted to resemble planula. The pneumatophore develops from the planula, unlike the other polyps. After fertilisation, the planula larvae form part of the plankton. Ovulated eggs are fertilized externally and take approximately 24 hours to develop into planula. The planula is a small larva covered with cilia.