fbpx

KidsKonnect

Lanternfish Facts & Worksheets

The Lanternfish is a small, deep-sea fish that is known for its bioluminescent properties and has long, thin bodies and large eyes that can detect light from even the darkest depths of the ocean.

Search for Worksheets

Worksheets /Science /Lanternfish Facts & Worksheets

Premium
Not ready to purchase a subscription? Click to download the free sample version   Download sample

Myctophids, also known as lanternfish, are small members of the family Myctophidae that inhabit the mesopelagic regions of the ocean. Their names come from the greek words μυκτήρ myktḗr, “nose”, and ophis, “serpent,” respectively. Lantern fish are typically found at depths of 300 meters; however, certain species have been seen swimming near the surface at night. 

See the fact file below for more information on the Lanternfish, or you can download our 27-page Lanternfish worksheet pack to utilize within the classroom or home environment.

Key Facts & Information

Description

  • True to their name, lanternfish flaunt their bioluminescence for all to see. A smaller but superficially related family is the Neoscopelidae, which includes the large-scaled lanternfish. 
  • The biomass of lanternfish is estimated to be anywhere from 1.8 to 16 gigatonnes, making up as much as 65% of the total biomass of deep-sea fish. This makes them one of the most abundant and widespread groups of vertebrates. 
  • These fish are caught commercially off the coast of South Africa, in the subantarctic, and the Gulf of Oman. The average lanternfish spends its entire life roughly 3,000 feet below the ocean’s surface.
  • When it gets dark, they come closer to the surface in search of food and to avoid being eaten by predators.

Physical Attribute

  • Sharp, silvery, deciduous cycloid scales cover lanternfish’s slender, compressed bodies. They also feature big, bluntly rounded heads, broad, elliptical to spherical lateral eyes, and a vast terminal mouth with rows of tiny teeth. There is one large dorsal fin, one small caudal fin, and one adipose fin, but the fins are insignificant.
  • The anal fin is a secondary dorsal fin that develops from the base of the dorsal fin or slightly behind it. Pectoral fins typically have eight rays, and can range in size and development from large and robust to small and degenerated or even be completely absent in a few species. Some species, like the genus Lampanyctus, have very lengthy pectoral muscles. The gas bladder in most lanternfish degenerates or fills with lipids as the fish matures; however, this is not the case for all species. There is no break in the lateral line.
  • Photophores (light-producing organs) are present in all but one species, Taaningichthys paurolychnus. They are usually found in pairs and are clustered in ventrolateral rows on the body and head. 
  • Specialized photophores on the caudal peduncle, close to the eyes (such as the “headlights” of Diaphus species), and bright patches at the base of the fins are also possible. 
  • The photophores have been observed to be arrayed in patterns specific to each species and are known to emit a dim blue, green, or yellow light. In some species, males and females display distinctively different patterns. The males’ bright caudal patches are often found higher on their bodies, while the females’ tend to be lower.
  • Most lanternfish are under 15 centimeters in length, while the largest ones can reach 30 centimeters. Species that live closer to the surface are bright blue, green, or silver, whereas those that inhabit deeper waters are dark brown or black.

Ecology

  • The diel vertical migrations of lanternfish are well known. During the day, most species stay in the dark bathypelagic zone, between 300 and 1,500 m deep, but as dusk approaches, the fish begin to climb into the epipelagic area between 10 and 100 m deep. 
  • The lanternfish may do this both to avoid being eaten and to follow the diel vertical movements of the zooplankton they eat. The lanternfish continue their descent back into the dark depths at dawn after spending the night grazing in the upper water column. 
  • Lanternfish improve the effectiveness of the carbon capture process known as the biological pump by discharging fecal pellets at depth.
  • Most species stick to coastal areas and hold their annual schooling over the continental slope. It is well-known that distinct species form thick, separate conspecific layers by depth, presumably to minimize competition. These strata, known as the “deep scattering layer” because of the gas sacs within them, were a source of much confusion for early oceanographers.
  • It’s possible that certain species that live in the deep don’t migrate at all and that others only migrate occasionally. It is possible that age, gender, latitude, and time of year all play a role in shaping migration trends. Each lanternfish species has its unique configuration of photophores, leading scientists to believe that this bioluminescence plays a function in communication during shoaling and courtship.
  • The lanternfish is an integral part of the food web in many marine ecosystems, providing sustenance to various predators. Predators include whales and dolphins, large pelagic fish like salmon, tuna, sharks, grenadiers, and other deep-sea fish (including other lanternfish), pinnipeds, sea birds, and most notably penguins, and giant squid, like the jumbo squid, Dosidicus Gigas.
  • There is evidence that lanternfish consume plastic trash floating in the water. Scientists are keeping an eye on the garbage patch in the eastern Pacific and report finding at least one lanternfish with more than eighty pieces of plastic chips in its digestive system. 

Deep Scattering Layer

  • During World War II, when sonar equipment was just being developed, operators were perplexed by what looked to be a fake sea floor 300–500 meters deep during the day and less deep at night. As it turned out, this was because of the millions of marine animals, especially little mesopelagic fish, that had swimbladders that reflected the sonar.
  • These creatures come up to the surface at dusk to feed on plankton. The layer is thicker when the moon is visible than when the clouds obscure it. 
  • According to data gathered by deep trawling, lanternfish may make up as much as 65 percent of the total biomass of deep-sea fish.
  • The ecological importance of lanternfish as prey for larger organisms is significant, and they are among the most abundant, diverse, and widely dispersed vertebrates.
  • Lanternfish have global biomass several times larger than the total catch of all fisheries combined (550-660 million tonnes). The biomass of lanternfish is largely responsible for the deep scattering layer found across the oceans. Because of the millions of lanternfish swim bladders, sonar readings often appear skewed.

Population

  • In terms of abundance, biomass, and diversity, lanternfish are today one of the most important groups of mesopelagic fish. Below 200 meters in dredges, their otolith record is the most common, and it is a good indicator of the entire Neogene period. 
  • Fossil otoliths found in the late Paleocene and early Eocene provide the oldest definite evidence of lanternfish. During the middle Eocene, lanternfish were prevalent over the shelf and upper-slope regions, suggesting that they did not initially evolve to live in the open ocean. 
  • Otoliths first appeared in bathyal sediments; they underwent a pronounced enlargement throughout this period. This shift is linked to the deep ocean cooling and nutrient and silica supply reorganization resulting from the change from a halothermal to a thermohaline deep-ocean circulation.
  • The number of diatoms, the primary food supply for the zooplankton feeding lanternfish and whales, is strikingly consistent with the size of lanternfish in the early Oligocene. The disparity of lanternfish increased over the warmer late Oligocene to early middle Miocene epoch while their otolith sizes shrank. During the “biogenic bloom” of the late Miocene, diatom abundance and gigantism in baleen whales co-occurred with a second, more permanent secular surge in lanternfish diversity and an increase in size. 

Lanternfish Worksheets

This fantastic bundle includes everything you need to know about the Lanternfish across 27 in-depth pages. These ready-to-use worksheets are perfect for teaching kids about the Lanternfish, a small, deep-sea fish that is known for its bioluminescent properties and has long, thin bodies and large eyes that can detect light from even the darkest depths of the ocean.

Lanternfish Worksheets
Lanternfish Worksheets
Lanternfish Worksheets

Complete List of Included Worksheets

Below is a list of all the worksheets included in this document.

  • Lanternfish Facts
  • The Little FIsh
  • Lanternfish Parts
  • Light Emitting FIsh
  • Which are not?
  • Importance
  • Got It
  • Photophores
  • A Maze-ing
  • Deep Sea Creature
  • Underneath

Frequently Asked Questions About the Lanternfish

What is a Lanternfish?

A Lanternfish is a small, deep-sea fish known for its bioluminescent properties. It has long, thin bodies and large eyes that can detect light from even the ocean’s darkest depths.

What does a Lanternfish look like?

A Lanternfish typically has a long and thin body with large eyes and a mouth below them. Its fins are usually between 10 and 20 cm long, though some species can be up to 30 cm. It typically has a brown-black coloration on its body, with the underside silver or white.

Where do Lanternfishes live?

Lanternfishes are found throughout most of the world’s oceans, ranging from 200m (650ft) to 2000m (6500ft). They prefer cooler waters near the poles and around continental shelves and islands.

How do Lanternfishes use their bioluminescence?

This light is generated by organs on the underside of their body and helps them both see and evade predators in the ocean’s dark depths. Lanternfishes can also use this light to attract prey, making it an essential tool in their survival.

What kind of food does Lanternfishes eat?

Lanternfishes have an omnivorous diet consisting mainly of small invertebrates such as squid, krill, and crustaceans. However, some larger species may feed on larger prey, such as shrimp or small fish.

Link/cite this page

If you reference any of the content on this page on your own website, please use the code below to cite this page as the original source.

Link will appear as Lanternfish Facts & Worksheets: https://kidskonnect.com - KidsKonnect, February 3, 2023

Use With Any Curriculum

These worksheets have been specifically designed for use with any international curriculum. You can use these worksheets as-is, or edit them using Google Slides to make them more specific to your own student ability levels and curriculum standards.

Related Resources