The clown anemonefish was first described by Cuvier (1830) as Amphiprion ocellaris. The genus name Amphiprion is derived
from the Greek word "amphi" which means on both sides and the Greek word "prion" which means saw. Other synonyms used in
previous scientific literature include Amphiprion melanurus Cuvier 1830 and Amphiprion bicolor Castelnau 1873.
The clown anemonefish is referred to as an anemonefish due to its symbiotic relationship with sea anemones. Other English
language common names include common clownfish, false-clown anemonefish, nemo, and western clownfish. Other
common names are almindelig klovnfisk (Danish); kakure-kumanomi (Japanese); bombin, gombing, inggu (Malay); and obyknovennaya
The clown anemonefish lives in the warmer waters of the Indian and Pacific Oceans. These fish are found in the
Indo-Malaysian region from the Ryukyu Islands, Japan throughout southeast Asia to northwest Australia.
World distribution map for the clown anemonefish
The clown anemonefish is a non-migratory species that lives in tropical, marine habitats associated with rocky or
coral reefs. They are found at a depth range of 10 to 50 feet (3 to 15 m). They form
symbiotic associations with the anemones Heteractis magnifica (most commonly), Stichodactyla gigantea, and
Anemones provide protection for these fish as well as their nests. In return the anemone
may benefit from fish consumption of parasites and increased water circulation from the fanning action of the fishes fins.
Anemonefishes have mucous covering which protects them from the sting of anemone tentacles. Acclimation must
occur before a fish is immune to the stinging tentacles. This is achieved by the fish swimming around the anemone and rubbing
its ventral side and fins on the tentacles.
© Doug Perrine
- · Distinctive Features
The clown anemonefish has one lateral line with interruptions and 34 to
48 scales along the lateral line. The dorsal fins contain a total of 10-11 spines and the pectoral fins have
17 rays which help to distinguish it from other species of anemonefish. The caudal fin is rounded.
Clown anemonefish closely resemble the orange clownfish (A. percula)
as pictured above
© Doug Perrine
The clown anemonefish resembles the orange clownfish (Amphiprion percula), however there are some characters
which help to distinguish it. One of the best ways to distinguish these two species is examination of the black band that separates the
orange color from the white bands present on the fishes body. The clown anemonefish has thin black bands, sometimes so thin that they may
appear to have no black bands at all, while the orange clownfish has thick black bands separating the orange
and white coloration of the body. Additionally, the clown anemonefish often has a slightly less brilliant color than the
orange clownfish. Also, viewed from a head-on perspective, the clown anemonefish's head appears plain while the
orange clownfish's head has a pronounced bulging face similar to a frog. These two species also differ in
the color of the iris. The clown anemonefish possesses a grayish orange iris which gives the appearance of
the eyes being larger than they actually are; the orange clownfish has a bright orange iris which has the
effect of making the eyes look smaller.
Clown anemonefish are orange with three white bands
outlined in thin black lines
© Doug Perrine
- · Coloration
The body of the clown anemonefish is orange with three white bands at the head, middle, and tail regions.
The middle band bulges forward toward the head centrally. There are thin black lines around the white bands that
appear to be missing unless closely examined. The tips of the fishes fins are rounded with black bands.
- ·Size, Age, and Growth
The maximum reported total length of the clown anemonefish is 4.3 inches (11.0 cm). These fish are believed to live approximately
6 to 10 years in the wild.
Clown anemonefish form symbiotic associations
with anemones including this Heteractis magnifica
© George Ryschkewitsch
- · Food Habits
The diet of the clown anemonefish consists of a variety of prey items. This anemonefish forages on algae, copepods, isopods, and
zooplankton as well as obtains food from the host anemone. The anemonefish will eat the dead tentacles of the anemone and any uneaten
prey that is captured by the stinging tentacles of the anemone.
- · Reproduction
The mating behavior of the clown fish has not been extensively studied but the general behaviors of anemonefish have
been reported. The clown anemonefish lives in a social group that has a strict dominance hierarchy.
The larger fish is always the female while the second largest is the male. They are the only two individuals that reproduce
within the group through external fertilization. The non-breeding individuals progressively decrease in size further down
Anemonefishes are characterized by being protandrous hermaphrodites which means that all fish develop into males first and then
potentially into females later. More than one anemonefish may reside in the same anemone, however if the female were to be removed
from the group or die, the largest male would then become female. Females control males through aggressive dominance, thereby controlling
the formation of other females.
This anemonefish is territorial with its host anemone and mating pairs are monogamous. Before spawning occurs, the male
will build a nest on a bare rock substrate close enough to the anemone to provide some protection from predators. Males attract
females through courting behavior characterized by extended fins, biting, and chasing. During spawning, the males become increasingly aggressive. When spawning
begins, the male will chase the female to the nest at which time the female will make several passes over the nest until
she releases her eggs. She lays eggs that are orange in color, measuring 3-4 mm in length and numbering from 100-1,000 depending
upon the age of the fish. The male then passes over the eggs and fertilizes them. The fertilized eggs remain attached to the bare
rock substrate by fine adhesive threads. The male looks after the eggs, fanning them with his fins and eating any eggs
that are infertile or damaged by fungus. However, once the eggs hatch, the male's parental care ends.
Water temperature affects incubation time with cooler temperatures resulting in longer periods of
time. Incubation time averages 6-8 days, followed by a planktonic larval stage that lasts for 8-12 days after which the
juvenile fish settles to the bottom substrate in search of a host anemone.
Brittle stars prey upon the eggs of the clown anemonefish
© Rachel Graham
- · Predators
- The number of predators the clown anemonefish has is greatly reduced because of its
symbiotic relationship with the anemone. The eggs are susceptible to attack from other damselfishes (Pomacentridae),
wrasses (Labridae), and brittle stars (Ophiotrichidae).
Importance to Humans
This fish is not harvested for human consumption, however they are often displayed in salt water aquariums due to
their high survival rate in captivity. The clown anemonefish is
also successfully raised in aquaculture facilities which decreases the pressure on wild populations to supply
the saltwater aquarium trade.
In some areas, local populations of the clown anemonefish have been impacted by over-collecting for the aquarium
trade. Other future threats may be habitat degradation through environmental impacts on coral reefs. However, at this time,
the clown anemonefish is not listed on the World Conservation Union (IUCN) Redlist as an endangered or
threatened species. The IUCN is a global union of states, governmental agencies, and non-governmental organizations
in a partnership that assesses the conservation status of species.