Bladefin Basslet

Quick Take

• A fish the size of your finger can cost as much as $10,000, and the reason has nothing to do with rarity laws or exotic coloring. Why collection is so costly →
• Collectors who manage to find one still face a brutal obstacle that makes owning this fish almost impossible. Deep-water habitat challenges →
• Its scientific name translates to 'sword-bearing', and the feature behind that name is hiding in plain sight on its body. Meaning behind the name →
• This fish looks peaceful enough to share a tank, but keeping two together is almost never an option, and there are multiple reasons why. Aggressive behavior explained →

The little bladefin basslet may remind you of a round-tail guppy, and they do have many things in common. Unlike the guppy, which has its origins in South America and is now found almost everywhere, the bladefin basslet is found in the western Atlantic Ocean at depths of up to 1,000 meters. You can buy your average guppy for a few cents, but the bladefin basslet can set you back as much as $10,000 for one!

Four Amazing Facts About the Bladefin Basslet

• The bladefin basslet is the only member of its genus, Jeboehlkia.
• It inhabits saltwater reefs at depths exceeding 490 feet.
• The fish is aggressive and shouldn’t be kept with conspecifics (if conspecifics can even be found) or even with fish that resemble it.
• The fish is a relatively recent discovery, as it was first described in 1967.

Classification and Scientific Name

The scientific name of the bladefin basslet is Jeboehlkia gladifer. Jeboehlkia comes from James Erwin Böhlke, an American ichthyologist, and gladifer is a Latin word for “sword-bearing.” This specific name references the spine in the fish’s dorsal fin. There are no subspecies.

Appearance

The bladefin basslet is a tiny fish that grows no longer than 3 inches. It is a bit torpedo-shaped, with a compressed body. The color is white, pink, or reddish, and the top of the head and the back of the neck are red. There’s also a white band that runs down the head. The fish’s anal and dorsal fins are edged with white, and it has white pelvic fins.

It has large eyes with bright red irises and a large mouth. The lower jaw is protruding (superior), and the snout is pointed. there are three spines on the lower edge of the gill-cover bone located behind the fish’s eye, and eight spines and nine soft rays in the fish’s dorsal fin. The second spine is very long and gives the fish its specific name of gladifer. The tail fin is round and red with a white edge.

Distribution, Population, and Habitat

The bladefin basslet is found in the western Atlantic Ocean from the Caribbean up through the waters off South Carolina. One specimen was found nearly 1,000 feet off the coast of New York. The reason that the fish is so expensive is that it is found very deep in the ocean, which makes it difficult to collect. Indeed, even if it is collected, the fish sometimes dies as it is brought up from the depths.

Predators and Prey

Not much is known about Jeboehlkia gladifer’s predators, but it is known to eat the tiny animals that comprise zooplankton. In captivity, the fish does best with live food, including brine and Mysis shrimp, as well as artemia supplemented with flakes or pellets.

Reproduction and Lifespan

Scientists don’t know much about the bladefin basslet’s reproduction, though pelagic larvae have been found. If it is like its relatives, it lays eggs that are externally fertilized, and these eggs become part of the plankton. The fish is believed to have a lifespan of between two and four years.

Fishing and Cooking

Even if the bladefin basslet didn’t cost thousands of dollars to buy, it would be too small to be used in cooking. As for fishing, it is only sought for the pet trade.

Bladefin Basslet Population

Scientists aren’t sure of the bladefin basslet’s population, but its conservation status is listed as Least Concern by the IUCN.