Clownfish are a type of damselfish and they are closely related to other reef dwelling fish, such as the garibaldi and Chromis. Most clownfish are found in the genus Amphiprion and only one, the maroon anemonefish (Premnas biaculeatus), is found in the genus Premnas. Clownfish have been on public display since 1881 and they remain one of the top selling fish in the pet trade. They are known to many children both through their dominant presence in many aquariums and the popular children's movie, 'Finding Nemo'.
Clown Anemone Fish
Scientific & Common Names
Kingdom - Animalia
Phylum - Chordata
Class - Actinopterygii
Order - Perciformes
Family – Pomacentridae
Subfamily - Amphiprioninae
Genus - Amphiprion and Premnas
Common names - Anemonefish, anemone clownfish, clownfish, clown anemonefish
Clownfish are colorful reef fish, with stripes of red, orange, yellow, or white on a dark background. Depending on species, they range from 4-7 inches and live anywhere from 6-10 years. All clownfish are born male. While some remain male their entire lives, others - generally the largest male - will switch genders to become the dominant female when that role is vacant, at which time they will rapidly grow. The next largest male will then become the dominant male and will keep the other males from maturing.
Male clownfish assume most of the care for the nest and eggs since females display little interest in parental duties. Males build a nest, hoping to please the female. She will then lay between a few hundred or a few thousand eggs in the shallow nest, in close proximity to the host anemone. The male will guard and clean the nest for the next week to ten days, until the young hatch. Upon hatching, the partially transparent larvae are at the mercy of the tides for the first few weeks of their lives, until they are strong enough to swim to the bottom, where they finally gain their coloration.
The best-known behavior shown by clownfish is their symbiotic relationship with stinging anemones. The stinging cells of anemones (called nematocysts)are able to deter most other fish, but the clownfish dwell within its tentacles with little or no injuries. It is believed that a combination of the fish's swimming style and their mucus coating protect them, although there is an acclimation period. The anemone benefits from the relationship because the fish cleans its hosts and keeps predators such as butterflyfish away. Although the invertebrate is perfectly capable of surviving without the fish, the inverse is not true. Clownfish in the wild are never found without a host and experiments have shown that they do not survive long without one.
Damselfish are believed to have diverged between 12-18 million years ago. The greatest diversity is found in the Indo-Pacific, which also contains the greatest diversity in marine reef species.
Clownfish are not listed as threatened, but there has been a noticeable decline in their numbers attributed to both collection for the pet trade and habitat loss. Many governments are placing regulations on collecting and there are captive bred options being expanded for the pet and aquarium trade.
Encyclopedia of Fishes (A Comprehensive Illustrated Guide by International Experts) Edited by Dr. John R. Paxton and Dr. William N. Eschmeyer
Reef Secrets by Alf Jacob Nilsen and Svein A. Fosså
Dr. Burgess's Atlas of Marine Aquarium Fishes (Third Edition) by Dr. Warren E. Burgess, Dr. Herbert R. Axelrod, and Raymond E. Hunziker III
Clownfishes: Anemonefishes of the Genera Amphiprion and Premnas by Richard F. Stratton