Amphiprion frenatus
Blackback anemonefish
(Also: Bridled anemonefish; Fire clown; Onebar anemonefish; Red clown; Red tomato clown; Tomato anemonefish; Tomato clownfish; oneband anemonefish)

Tomato clownfish are known to be found in the Oriental Region of the Western Pacific, namely, South China Sea, Indonesia, Singapore, Malaysia, Thailand, Viet Nam, China, Philippines, and Taiwan. They have been found to inhabit waters as far north as the Ryukyu Islands and the southern parts of Japan. The longitudinal coordinates for this area are 25 N - 35 S. (Fautin and Allen, 1992)

Tomato clownfish are known to inhabit lagoon reefs, particularly with embayments. According to Fautin and Allen (1992), this species does not migrate, and has developed a relationship with the anemone Entacmaea quadricolor. (Fautin and Allen, 1992)

Tomato clownfish have a distinct orange body, which may turn black in older individuals. Behind the head of the fish, a black-edged bar extends from the top of the head towards the belly. A second black-edged white bar may be found around the mid-section of the body.

Amphiprion frenatus have 9-10 dorsal-fin spines and 16-18 dorsal soft rays. This species also has 2 anal-fin spines and 13-15 anal soft rays.

Tomato clownfish can grow up to 14 cm in length. Females are larger than males. (Fautin and Allen, 1992)

Beginning as an egg, tomato clownfish will take about one week to hatch and become larvae. After hatching, larvae will drift for about 16 days in plankton-rich waters. At the end of this drifting journey, the larvae will look for anemones of their own to inhabit. Their development from there depends upon social roles. A juvenile will only develop into a sexually mature male if this role in the anemone is not already filled. When the female of the anemone is absent, the largest mature male will then change into the sexually mature female. (Myers, 1999)

Damselfishes that live in anemones have biological attributes that help them to live in this unique environment. As they mature, they gain a special mucus coat that has specific chemicals that counter the anemone's sting. These fishes are also known to have a special swimming pattern that helps them to survive in the anemone. (Allen, 1997)

According to Wickler (1963), Amphiprion frenatus, like other anemonefishes, is not immune to the anemone, but instead stimulates the nematocysts (stinging cells) to fire. If these fish choose to live outside of an anemone, they usually take up residence in coral branches.

It is possible to make a general guess at the age of tomato clownfish by the stripes on their bodies. When young, these fish will have more white stripes on their hind regions. However, not all individuals lose the juvenile pattern as they mature. (Wickler, 1963)

A pair of tomato clownfish will mate for life. However, if one partner leaves, then the other will find a replacement for its lost mate. (Wickler, 1963)

One of the most interesting characteristics of anemonefishes is that all offspring are born male, and mature as such. Therefore, all females are sex-reversed. This sexual metamorphosis occurs when the female of a group leaves. This will trigger the largest male remaining to switch sexes and will allow the largest juvenile to become a mature male. The adult pair will then continue to stunt the growth of the remaining offspring.

When courting a female, a male will exhibit both sterotyped and ritualised behavior. A male will chase a female, as he becomes more bold. He also has the tendancy to show off for his mate by erecting his dorsal, anal, and pelvic fins as he remains in one spot near her, much like a statue. Another form of behavior recorded among A. frenatus is "signal jumping," which means that a male will move rapidly around an anemone in an up and down manner. In the beginning of their courtship, a male will also spend a large amount of time picking out the nesting site that he will eventually guard if he is successful in mating with a female. At the end of courtship, she will also help her mate in clearing the nesting site of algae and other debris. When laying eggs, a female will place the adhesive eggs on a rock near the anemone. The male then watches over them until they hatch.

Tomato clownfish, like all Amphiprion, will breed all year long in the tropics, but only in the warmer months of temperate locations. Spawning occurs during a full moon, which is characteristic of all anemomefishes. (Fautin and Allen, 1992; Myers, 1999)

After the eggs are laid near the host anemone, the male looks after the eggs, and both the male and female will protect the eggs as well. After the larvae hatch, they swim away to find an anemone of their own to inhabit, and no further care is given by the parents. (Myers, 1999; Wickler, 1963)

The knowledge surrounding longetivity for this species is sparse, even though more is known about this species than other anemonefishes. At most, they live 6-10 years in teh wild, and 18 years in captivity. (Fautin and Allen, 1992)

Tomato clownfish, like many other anemonefishes, have a complex social hierarchy that rules not only who is in charge of the host anemone, but also the size of the other fish that live within it. At the bottom of the hierarchy are the juvenilles. Usually several juveniles will share one anemone with a mating pair. A sexually mature male is next in line in the hierarchy, with the female at the top. All A. frenatus are born as males, and will only change into a female when the female of the host anemone has left.

One cannot tell the age of a tomato clownfish by simply measuring its size. The female initiates a non-threatening, harassing behavior towards the mature male with whom she shares the anemone. From this behavior, the male in turn harasses the juveniles in the same manner. Since the juveniles are constantly being chased by the male and sometimes the female, they seldom have time to eat enough nutrients to grow any larger. This behavior inhibits the growth of the newer fish to the anemone. Even the male is half as large as the female due to her consistant harassment of him. Therefore, when the female is absent from the anemone, both the male and the juveniles experience a large growth spurt. (Fautin and Allen, 1992)

The territory size of the anemonefishes depends upon the size of the fish. The smallest tomato clownfish will usually stay very close to the host anemone when foraging for food due to their increased risk of predation. Larger anemonefishes that are at the top of the social heirarchy in the host anemone will travel many meters from their host. (Fautin and Allen, 1992)

Not much is known about the communication of tomato clownfish, except that when they are either defending themselves or attacking others, they will make a "tack-tack" sound. (Wickler, 1963)

Tomato clownfish eat algae, zooplankton, and small, aquatic crustaceans.

A characteristic of all anemonefish belonging to the genus Amphiprion is that they are mutualistic with anemones. This means that they live together with large anemones, and each helps the other species. When a tomato clownfish brings food back to an anemone, the anemone is rewarded with crumbs from the meal. In turn, the fish is protected from predators while within the anemone. The anemonefish also help the anemones by cleaning and caring for them, which again benefits the anemone greatly. (Allen, 1997)

In all of the literature available, no specific predators were given for the tomato clownfish or even for their genus, Amphiprion.

Amphiprion frenatus is a symbiont to the bulb-tentacle sea anemone, Entacmaea quadricolor. Although they can both live without each other, their health and rate of survival are increased when tomato clownfish live within its tentacles. (Fautin and Allen, 1992; Fautin and Allen, 1992)

Tomato clownfish have a positive economic importance for humans through the pet trade industry.

No literature found stated that tomato clownfish have a negative economic importance for humans.

This species is not listed on any of the endangered or threatened lists that are listed below.