Planula
A planula is the free-swimming, flattened,
Development
The planula forms either from the fertilized egg of a
Depending on the species, the planula either metamorphoses directly into a free-swimming, miniature version of the mobile adult form, or navigates through the water until it reaches a hard substrate (many may prefer specific substrates) where it anchors and grows into a polyp. The miniature-adult types include many open-ocean scyphozoans. The attaching types include all anthozoans with a planula stage, many coastal scyphozoans, and some hydrozoans.[5]
Feeding and locomotion
The planulae of the subphylum Medusozoa have no mouth, and no digestive tract, and are unable to feed themselves (lecithotrophic), while those of Anthozoa show more variation and can be both lecithotrophic, parasitic or feed on plankton or detritus.[5][6][7]
Planula larvae swim with the
References
- ^ ISBN 0-03-025982-7.
- PMID 21558236. Retrieved 2022-02-03.
- S2CID 5337426.
- ^ Cytological aspects of similarity and difference of Myxozoa and Cnidaria
- ^ S2CID 16969737.
- ^ British Anthozoa (Coelenterata: Octocorallia and Hexacorallia)
- ^ Evolution of Metazoan Life Cycles and the Origin of Pelagic Larvae