11 Strange But True Facts About Lancetfish

May 16, 2019

The lancetfish is one of the stranger fish found in Alaskan marine waters. Here are some interesting facts about this unusual fish.

The Lancetfish.

The Lancetfish.

Find out why Lancetfish Really are Creatures from the Twilight Zone

  1. With gaping fanged jaws, enormous eyes, a sailfin, and long, slithery body, lancetfish look like they swam out of prehistoric time.

  2. Their dinosaur-worthy scientific name, Alepisaurus, means "scaleless lizard." Lancetfish are naked of scales with skin covered in pores.

  3. Growing to more than 7 feet long, lancetfish are one of the largest deep-sea fishes, swimming to depths more than a mile below the sea surface.

  4. Lancetfish live mainly in tropical and subtropical waters but migrate as far north as subarctic areas like Alaska’s Bering Sea to feed.  

  5. Lancetfish are hermaphrodites, possessing both male and female sex organs simultaneously. Very little is known about lancetfish reproduction and development.

  6. Lancetfish flesh is watery and gelatinous and generally not appetizing to humans. However, other large predators like sharks, tuna, and fur seals—and other lancetfish—are not so picky.

  7. Since gelatinous muscles are not built for long chases, scientists suspect lancetfish are ambush predators, floating quietly camouflaged in the water until unsuspecting prey comes near enough to strike.

  8. NOAA scientists are looking at the stomach contents of lancetfish to understand the mysterious midwater food web.

  9. Food in distensible lancetfish stomachs is often found in a nearly pristine state, barely digested. Scientists speculate that lancetfish may eat as much as they can whenever they find food, then digest it later when they need it.

  10. Lancetfish are notorious cannibals and also feed voraciously on many other fish and invertebrates. Many descriptions of new species of fishes, squids, and octopuses have been based on specimens collected by lancetfish and taken from their stomachs.

  11. The cold, dark midwater depths where lancetfish hunt are known as the twilight zone.

Additional Resources

Last updated by Alaska Fisheries Science Center on May 29, 2019