Wrought Iron Butterflyfish

Quick Take

• Most butterflyfish are explosively colorful, but this one breaks that rule entirely, and that's exactly why collectors pay a staggering price for it. See why collectors pay up →
• Its scientific name hides a surprisingly poetic origin story that has nothing to do with butterflies. Explore the name's origins →
• This fish forms lifelong monogamous bonds, yet breeding it at home comes with a dark twist most owners don't anticipate. Discover the breeding twist →
• It's endemic to a tiny stretch of ocean near Japan, yet there's one unexpected place in the U.S. where you can see one right now. Find out where to see one →

The wrought iron butterflyfish stands out from other butterflyfish species because it isn’t nearly as colorful. Instead, its notable metallic black scales are adorned with hints of yellow, making it a beautiful addition to home tanks for anyone with a preference for saltwater fish. They are among the most expensive aquarium fish in the world, and they are incredibly rare to be found naturally outside of Japan.

5 Wrought Iron Butterflyfish Facts

• The wrought iron butterflyfish is endemic to several Japanese islands, making it a rare sight to see anywhere else.
• The main reason that this fish has any commercial appeal is that it is for sale for thousands of dollars in the pet trade.
• They are one of the most expensive fish in the world, often priced above $4,000. However, if you want to see one, it can be found in the Waikiki Aquarium in Hawaii.
• The typical environment of this species of butterflyfish is near saltwater coral reefs, which is where they source their food.
• They are quite fast and will quickly zip away from predators.

Classification and Scientific Name

The Wrought Iron Butterfly Fish has the scientific name Chaetodon daedalma. It is part of the Chaetodontidae family and the Actinopterygii class. There are no recognized subspecies currently.
The name for this fish was originally decided by David Starr Jordan and Henry Weed Fowler, who were ichthyologists. The word “daedalma” is a type of embroidery, used to describe the pattern found along the body of the wrought iron butterflyfish. The word “Chaetodon” comes from the Greek language, which is a combination of “chait” (“hair”) and “odous” (“teeth”).

Appearance

The reason this species of butterflyfish has its name is the metallic black color of its body. Its dorsal, caudal, and anal fins are decorated in yellow, though there are some markings scattered across the scales of the body as well. The scales have black margins with a yellow center. Most people see butterflyfish as colorful fish, so these markings contrast clearly with the appearance of other species.

The length of this fish varies, typically reaching at least 5–6 inches.

Distribution, Population, and Habitat

The wrought iron butterflyfish primarily lives in the Pacific Ocean near Japan. Based on their current numbers and stability, the IUCN states that they are of Least Concern.

Where to Find the Wrought Iron Butterflyfish and How to Catch Them

Since the wrought iron fish is so specific to a certain region, finding them outside the Japanese islands south of Sagami Bay is possible only if they have been acquired through the pet trade. They prefer to live in depths of at least 33 feet, and they are found in groups called schools with at least 10 other individual fish.

If you want to find one of these fish, you’ll have to look during the daytime when they might be eating algae or benthic invertebrates as part of their diet. If they are eating, you’ll likely see their entire group together. They can occasionally be found in public aquariums, sometimes in exhibits that replicate their native Japanese reef environments.

Due to their diet, the wrought iron butterflyfish live near rocky reefs. While a specific population for the wrought iron butterflyfish is unknown, the IUCN sees them as Least Concern with a stable population.

Predators and Prey

The wrought iron butterflyfish doesn’t really have any defense mechanisms on its body to protect itself. However, to escape their predators, they’ll quickly swim away if possible. These fish might indulge in invertebrates, but much of their diet consists of algae. They are not active hunters as adults or juveniles, requiring only places to hide and regular feeding when kept as pets.

What eats the Wrought Iron Butterflyfish?

The predators associated with these butterflyfish include larger fish around the same reef. These larger fish include moray eels, groupers, and snappers. Even as a juvenile fish, these fish can be consumed by sharks and other big animals.

Since the wrought iron butterflyfish is rarely sold in restaurants, humans are not one of its main predators.

What do Wrought Iron Fish eat?

This butterflyfish isn’t typically a hunter, consuming plankton and invertebrates that happen to be around the coral reefs that they live near. They also consume algae.

Reproduction and Lifespan

During breeding, this butterflyfish is monogamous, pairing to fertilize their eggs. They form long-term bonds. The fertilization is external, and the water pH must be between 7.0 and 7.8. If you are trying to breed them at home, their water just needs to be cooled. The female will lay eggs with the males fertilizing them. The eggs are released into the water column and attach to floating plants in the tank.

Like most fish, there’s no parental care for the eggs. If they are left to hatch in the tank (which takes about 7 days), the parents will likely eat them while they are still fry. Because they are immobile at this stage, the baby fish are poor hunters.

Fishing And Cooking

Trade in this butterflyfish is limited because purchase costs are high and they require cool water conditions to survive. Exportation is the easiest way to distribute them to specialty pet stores. It is not considered a commercial fish because it is not typically caught for sport or food.

Wrought iron butterflyfish, like other species of butterflyfish, are not prepared as food. Many people avoid such fish due to concerns about toxins, but the wrought iron butterflyfish is not toxic. They are better kept as pets for aquariums.