Ancient Lamprey (S/F)

Prop models used in Jurassic World: Dominion (2022)

An undescribed species of prehistoric lamprey approximately 5 feet (1.5 meters) long has been reported among various de-extinct species. It belongs to the order Petromyzontiformes, and appears similar to lampreys in the family Petromyzontidae (the northern lampreys), but other scientific information about it is lacking. Lamprey fossils are known as far back as the late Devonian period in the form of the small 360-million-year-old species Priscomyzon riniensis, which has most of the adaptations seen in later lampreys. Since they are mostly cartilaginous, they do not readily fossilize. Therefore, ancient DNA may be the only form in which this species was preserved by the fossil record, with remains of its body lost to time.

It represents the largest-known lamprey species, exceeding the modern sea lamprey (Petromyzon marinus) in size by one to two feet. The original habitat of this species, like other paleontological information about it, remains unknown, though lampreys are found in coastal and inland habitats throughout the world’s temperate regions. This species is noteworthy for being the first known de-extinct agnathan, having been cloned from ancient DNA sometime between 2018 and 2022. Its creator remains unidentified.


This de-extinct lamprey is the largest agnathan (jawless fish) yet known, reaching lengths of around five feet or 1.5 meters in length. If its mass is similar to the sea lamprey, it likely weighs around 1.5 pounds (700 grams) when fully grown. About a third of its total length is the main body, with the tapering tail constituting the other two-thirds. Its lengthy, scaleless body makes it superficially resemble an eel, although they are not closely related. Lampreys differ from most other living fish because they lack jaws, making them among the more primitive vertebrates. A large oral sucker marks the beginning of its mouth. Being jawless, its teeth are situated in rings, not rows. Its keratinous teeth are designed for gripping objects, and are hollow to accommodate new teeth growing in underneath. Lamprey tongues are built like pistons with three tough plates called laminae on the tip. There is a single nostril atop the head, and four eyes; in addition to the two obvious large ones there is a pineal eye and parapineal eye also on top of the head. The larger eyes are covered by a transparent skin membrane. Seven circular external gill pores are lined up behind each eye.

Lampreys have cartilaginous skeletons, similarly to sharks and rays, but are far more primitive; they do not even have true vertebrae. They have no scales, as mentioned above, and also lack paired fins. When alive, this species probably has dorsal and caudal (tail) fins, but they have been stripped off in the market-ready specimens this species is known from. However, lampreys are some of the most highly efficient swimmers in the world. As they move, their bodies create areas of low pressure around them, which pulls the body forward through the water. Their mouths can be used for clinging to rocks, either to move the rocks around or to resist strong currents. In carnivorous lampreys, the mouth is also used to cling to food sources. So that the lamprey can breathe while feeding, the pharynx is divided by a valve known as the velum, which ensures that the ventral part of the buccal tube can be used for respiration while food passes through the throat. This way, valuable fluids from the prey are not lost through the gills. The intestines not only aid with digestion, but also desalinate water from the lamprey’s environment to help it maintain osmotic stasis.

Since only dead specimens have so far been identified, the natural coloration of this lamprey species is not known, but appears to be light brown or yellowish. Most lampreys have countershading patterns, with their undersides being lighter in color, which helps them to camouflage. Many species also have patterned skin which aids them in remaining hidden from predators. While the dead specimens show darker-colored heads and pale trunks and tails, with grayish veins showing through the skin, they probably had more color when they were alive.


While only the adult form of this lamprey has been observed, the ontogeny of lampreys in general is fairly well-understood. Larvae, called ammocoetes, hatch from eggs laid in freshwater nests and will grow between three and eight inches (eight to twenty centimeters). At this stage, they may change color based on time of day, being darker during the daytime and paler at night. The ammocoetes drift downstream and filter-feed in nutrient-rich silty riverbeds, using photosensitive cells on their tails to help remain buried. At this stage, the fish’s eyes are poorly developed and completely covered in skin, meaning ammocoetes are blind. Lampreys evolved to go through an ammocoete stage sometime after the Devonian period, with the earliest lampreys hatching with their mouths fully-developed.

The ammocoete stage may last up to eight years (though some species remain this way for just one or two), and then a long metamorphosis begins. In most species, this metamorphosis takes three or four months. During this phase of the lamprey’s life it does not eat at all. As it metamorphoses, it loses its gallbladder and biliary tract, while its endostyle (a filter-feeding apparatus) changes into the thyroid gland. The eyes, teeth, and oral sucking disc develop at this stage.

Once adulthood is reached, the lifespan of the lamprey is highly variable. Most species are either herbivorous, or do not feed at all as adults; these tend to be freshwater species. About half of the carnivorous species are anadromous, migrating into the sea once they reach adulthood. They return to freshwater when it is time for them to breed, which typically occurs about four years into their adult life. Lampreys are semelparous: after breeding, both adults die.

Sexual Dimorphism

Most lampreys do not show significant sexual dimorphism. Mature males have a ridge of fat cells near the anterior dorsal fin which produce heat, used for stimulating females to release eggs.

Preferred Habitat

Most modern lampreys are freshwater animals, though their Paleozoic ancestors lived in oceanic environments. Out of the thirty-eight currently identified extant species, nine are anadromous, meaning they migrate into the ocean when they mature and return to freshwater environments to breed (though these species can live in fresh water permanently). The precise habits of this prehistoric species are unknown. However, it can be assumed based on its modern relatives that it hatches, metamorphoses, and breeds in fresh water, and is probably capable of living in fresh water its entire life.

Lampreys in the modern day favor temperate environments and are not found in the tropics. While Earth’s present-day climatic conditions are quite different from millions of years ago, it is probable that this lamprey’s original environment was a temperate one as well, found some distance to the north or south of the equator.

BioSyn Genetics Sanctuary

Following the events of 2018, de-extinction technology became widely available and dozens of new species were brought back from extinction. BioSyn Genetics was authorized by the United States and other countries to capture and contain particularly problematic creatures, holding them safely within BioSyn Valley‘s sanctuary in the Dolomite Mountains. Most of their attention, however, was turned to dinosaurs and pterosaurs. Fish seem to have escaped their attention. Now that the BioSyn Genetics Sanctuary is under strict supervision by the United Nations, policies in place may change, but whether the collection and containment of prehistoric lampreys will become a priority has yet to be determined. The valley does have rivers and lakes, as well as a large alpine reservoir, which could serve as lamprey habitat.

Black market

It is unknown what party originally recreated this lamprey species. In fact, it is known only from dead specimens sold at the Amber Clave night market in Valletta, Malta in early 2022. No live specimens were recorded, though the sheer number of lampreys strung up for sale or cooking on spits suggested a breeding facility somewhere. One can imagine that the lampreys are bred in some Mediterranean country with easy access to Malta.

Wild populations

Once, this lamprey lived in populous numbers in waterways in temperate parts of the ancient world. Its habitat and population sizes cannot be determined as no fossils have ever been found. It is not even known when precisely it lived; the oldest lamprey fossils currently known date back to around 360 million years ago, in the Famennian stage of the late Devonian period. However, big lampreys such as this one did not evolve until far later. In fact, the largest lamprey identified to species level is the modern-day Petromyzon marinus, the sea lamprey. The size of this prehistoric species indicates it probably lived alongside fairly large aquatic life, suggesting it originally lived during the Mesozoic or Cenozoic eras. Ancestrally lampreys were marine, but after the Paleozoic era they began to specialize in freshwater environments. This species was probably found in lakes and rivers, though it may have been anadromous, living in coastal marine environments as an adult before coming back to the rivers to breed.

No fossils have ever been found, and whoever cloned this species has disclosed nothing about it, so its paleontology is mostly conjecture. All that is known for certain is that it lived before the evolution of the human species, and eventually, due to changes in its environment, it died out. Then, millions of years later, samples of its preserved DNA were found in iron-rich sediments, allowing scientists to clone it. Like all de-extinct animals, it was likely subject to gene splicing, making it in some ways different from its ancestors. At the very least, it would have had to be adapted to the modern world, which differs greatly from the prehistoric Earth.

Since this animal’s recreation (sometime between 2018 and 2022), it has not been reported in the wild. In fact, little is known about its presence in the modern world at all. It was cloned exclusively for consumption off the black market, so it is not even known where in the world it is bred.

Behavior and Ecology
Activity Patterns

During the ammocoete stage, lampreys often change color on a diurnal cycle, being darker-colored during the day to blend in with river substrate and paling at night. However, they are passive filter-feeders at this stage and do not move around much; they cannot even see. The behavior patterns of adults are more variable, depending on the dietary and breeding behaviors of the species. This particular species has not been observed alive.

Diet and Feeding Behavior

Of the modern lamprey species, eighteen are carnivorous, including the larger ones. The closest modern analogue for this prehistoric species is the sea lamprey, which feeds parasitically on a variety of fish. It is known to target sharks and rays, as it can tolerate high urea levels in its food. On occasion, some carnivorous lampreys will feed on marine mammals. This prehistoric lamprey is quite large, bigger even than the sea lamprey, so it is probably a carnivore. During the larval stage, lampreys are filter-feeders, requiring particularly high concentrations of nutrients in their water to sustain themselves; they will consume plankton and other tiny organisms.

To feed, carnivorous adult lampreys will use their oral disc. Lacking jaws, they cannot take bites out of prey, but instead they are specialized as parasites. They use two feeding strategies, hematophagy and micropredation. Lampreys use their mouths to suction onto prey and latch into place using the rings of teeth. Once attached, their tongues are brought into play, using the three laminae to scrape away the skin of the prey and seek out sources of blood and other fluids. If the lamprey feeds mostly on blood, it will have large buccal glands which secrete an anticoagulant called lamphredin, ensuring that the blood keeps flowing while the fish consumes it. Some species feed on the prey’s meaty tissue along with blood; they have smaller buccal glands and use less anticoagulant. They may eat organs such as intestines. Whether this prehistoric lamprey eats mostly or only fluids, a mix of both tissue and fluids, or mostly or only tissue is not known. Most modern lampreys are herbivorous and eat algae, while other species do not eat at all as adults, but these tend to be smaller species.

Victims of lamprey bites often die from blood loss, or else infection. Despite this, lampreys do not intentionally kill their prey, since they do not usually scavenge. The deaths of their prey items are just an incident of their feeding behavior.

Social Behavior

Although they are not especially intelligent, lampreys can be found in large groups depending on the species. They congregate in suitable habitats, especially where food or breeding sites exist. The most important interactions they have with each other are related to reproduction; many species build nests out of rocks and other objects where females will lay their eggs. How this ancient lamprey communicates is unknown, but it may involve pheromones or visual signaling.


Female lampreys can lay huge quantities of eggs, sometimes up to a hundred thousand at a time. When it comes time to lay eggs, the lampreys will travel upstream, using their suction mouths to cling to rocks and clamber over ramps. Once they reach their breeding grounds, they will build nests called redds out of rocks, pebbles, and gravel from the riverbed. Mating takes place in the redds. Males attract females using pheromones, then stimulate them using heat-producing fat cells located near the anterior dorsal fin. Fertilization is external, but the lampreys still have a physical mating practice; the male and female intertwine, and the male will fertilize the eggs as soon as the female releases them. Lampreys are semelparous, meaning they breed only once. Both adults die after the eggs are fertilized.

Depending on the species, the larvae (called ammocoetes) can remain in that stage for up to eight years. When they hatch, they drift downstream to quiet, nutrient-rich parts of the river and bury themselves in silt. Here they remain and filter-feed on plankton and microorganisms. The rate of water flow across their feeding apparatus is extremely low, so they need very dense nutrients in their water in order to survive. Once metamorphosis begins, they will go months without eating until the process completes, so they must have plenty of energy stored up before this. In some species, and probably this one, they will travel toward the ocean and begin feeding on animals once they reach adulthood. A year or more of feeding, and the lampreys will then be ready to breed. At this point they will begin the upstream journey.


Lampreys mostly discern the world around them through scent and sight, but they do not appear to communicate much with each other. They can visually see each other, and detect pheromones by scent, which probably helps them discern where other lampreys are. During migrations, large numbers of them will travel upstream to breed, which is the only time they have significant interactions with each other.

Ecological Interactions

This species of lamprey is quite large, suggesting it is carnivorous and feeds parasitically on other animals during its adult stage. In its original time period, it probably fed on larger aquatic creatures; depending on what time period it lived in, it might have fed from large reptiles or mammals in addition to fish. Today, its role in ecology is less knowable, since there is no evidence of it living in the wild. Still, it could probably feed from many of the same species that sea lampreys do, such as sharks and rays. With an ability to tolerate high urea concentrations in its meals, shark blood is palatable to it.

Although lampreys feed on blood and tissue without actually eating their hosts entirely, they are still deadly. Especially in one of this size, hosts can be so drained of blood that they cannot survive. Hosts that survive the blood loss may be susceptible to infection in the bite wound. In aquatic environments, pathogenic microorganisms and small parasites can very easily infect a host, since the injury is in direct contact with the medium containing the pathogen all the time. These infectious organisms benefit from the bites of the lamprey.

Lampreys themselves are far from the top of the food chain, being fed upon by larger fish. They are especially vulnerable in the ammocoete stage, in which quite a few predators of the rivers will eat them. Adults are a bit safer; in bigger lampreys, the main predators are humans. Still, some fish can threaten them, even species lampreys will feed from. With their soft, scale-free bodies, they are easily defeated by another fish’s jaws.

Cultural Significance

Although this lamprey is mostly unknown, lampreys in general have been known to societies especially in the Northern Hemisphere for most of history. Because of the parasitic habits of many carnivorous species, lampreys generally have a negative connotation in Western cultures, where they are sometimes used to symbolize harmful dependency. The fact that most lampreys feed on algae is lost on many people. The unusual appearance of this fish, with its suction-cup disc and rings of sharp teeth, have lent inspiration to monstrous creatures in folklore and modern popular culture. Lampreys being portrayed as frightful has only become more common in recent times, with the sea lamprey being introduced to the American Great Lakes where it is now invasive and harms fish populations.

Lampreys are variously mentioned in historic literature, particularly surrounding the Roman equestrian Publius Vedius Pollio, who was infamous for keeping a pool of lampreys into which he would throw slaves he disliked. The fish is recalled more positively in stories of the statesman Lucius Licinius Crassus, who kept a beloved lamprey as a pet and greatly mourned the animal when it died.

This giant prehistoric lamprey has thus far not established in the public consciousness, but with attitudes toward de-extinction mixed at best, one can only imagine the public reaction to a giant, parasitic prehistoric fish being brought back to life.

In Captivity

While nothing is known about the breeding and keeping of this de-extinct lamprey, the fish in general are well-known in aquaculture from throughout history and around the world. These fish have been farmed in Europe, Asia, North America, and elsewhere since ancient times, with European examples being particularly well-recorded. Only the carnivorous species live particularly long, with other species being quite short-lived, and they can be difficult to keep because of their dietary needs. These animals are not really suited for a display aquarium, and are instead mostly raised for education and food.

Adult lampreys are often collected while they migrate upriver to spawn. They are easy to catch in this state, as they are fully occupied with their upcoming mating and therefore not paying rapt attention to their surroundings. Ammocoetes can also be caught from the wild by sifting them out of the mud. These larvae are more easily kept in an aquarium, since they are filter-feeders. They need calm water and biologically active sandy or silty substrate where they will bury themselves. Brewer’s yeast can be fed to captive ammocoetes.

Ammocoetes will mature into adults in an aquaculture system, and at that point they will need to eat a very different diet. The carnivorous species need fluids and sometimes animal tissue, and can be fed live fish to cling to. They may also take freshly-dead or recently-thawed fish meat. In some species, spinach or beef hearts can substitute for meat. Once the fish are fully mature and able to breed, they will build redds among rock and gravel. Shortly after laying eggs, both adults will die, and should be removed from the ecosystem as soon as possible. The eggs are laid in rocky substrate, but when the ammocoetes hatch, they will instead need silt or mud. This is the main cause of lamprey aquaculture failure; larvae will not survive in the wrong substrate, and in nature, they drift downstream to find suitable homes away from the nesting site. A successful aquaculture system will need to substitute this natural process.


This primitive creature is noteworthy for being the first cartilaginous fish and the first agnathan to be brought back from extinction, likely using novel methods that expand upon those pioneered by InGen. Modern lampreys are already considered highly interesting to scientists, and with this long-extinct species added to the mix, only time will tell what new research will become possible.

Historically, lampreys have been considered useful evolutionary models for early vertebrates, being one of the most primitive surviving examples. In particular its brain is considered very similar to the basic vertebrate brain. The lamprey is used as a model organism in many forms of neurological research; electrical stimulation has been used to yield physiological responses, demonstrating how the brain and spinal cord transmit commands to the muscles. The particular parts of the brain that control various bodily functions have been identified. Lamprey nerve fibers are also quite large, which makes microinjection an easy process in these fish. They are remarkably resilient, able to recover their full bodily functions after their spinal cords are severed.

Lampreys show a genetic trait that could potentially aid in curing cancer. They are able to delete parts of their genome after the genes have served their purpose in embryonic development, with around 20% of their genome being removed from their somatic cell lineages at the appropriate stage of development. In humans, the comparable genes remain in these cells for the entire lifespan, and if inappropriately activated later in life, can cause cells to become cancerous. If scientists can discover how the lamprey manages to remove these genes, it could lead to the prevention of certain cancers in humans.

Outside of medical research, lampreys have a number of scientifically interesting traits. They are among the most energy-efficient swimmers in the world, since their movements create areas of low water pressure that pull their bodies forward. Lamprey immune systems involve leucocytes (white blood cells) which express surface variable lymphocyte receptors, functioning similarly to the T cells and B cells in more advanced vertebrates. Many traits of the lamprey are considered significant in mapping the history of vertebrate evolution, not just in terms of anatomy but also physiology. As more fossils are found, our understanding of these creatures’ history becomes more complete, and with the advent of modern paleogenetic research, these studies can become more comprehensive than ever.


This ancient lamprey species is almost entirely unknown, being present only at whatever facilities are breeding it and in the black market where it is commonly sold as food. De-extinction politics has so far focused almost exclusively on dinosaurs and other reptiles, sometimes to the detriment of the world (such as during the 2022 hybrid locust plague, which was more or less ignored by governmental authorities until it reached disastrous proportions). With bigger and more dramatic creatures taking center stage, animals such as this humble lamprey can largely avoid controversy. However, should it become invasive in water systems the way some modern species such as the sea lamprey have done, it may become a more pressing matter to regulate the trade and breeding of this fish.


Prehistoric lampreys are one of the first species to be brought back from extinction explicitly for culinary purposes. At the moment, since its creation is legally dubious, its meat can only be found on the black market; it is unknown whether it has been genetically modified to achieve its impressive proportions. Its size means it yields more meat than other lampreys. Lamprey meat has been prized since the time of ancient Rome, and remains popular in Europe and Asia today. North American species are also popularly caught for food. This prehistoric lamprey may be prepared using many of the methods already used for their modern relatives: they may be baked into pies, as is tradition in Gloucester, or cooked with rice as is common in Portugal. They can be pickled in vinegar or grilled or smoked, as is popular in Finland. They are also common in Japanese cuisine in the form of yatsume kabayaki. Some species have toxic mucus and serum, so they must be cleaned thoroughly before consumption. Lampreys are valued for their rich, meaty flavor and texture. This ancient species is known for being grilled in chunks or smoked whole over an open fire, and is popular in Malta.

Lampreys are commonly used as bait in Britain for catching larger fish, though the expenses inherent in bringing a species back from extinction mean that this ancient animal would be suited best as a delicacy for people. However, scrap meat could still be used to lure in other fish.

While they are valued as food and as biomedical research models, lampreys can also be pests of economic significance. The sea lamprey damages important fish in the Great Lakes, where it has become invasive after finding its way into the lakes during the 20th century. Chemical toxicants called lampricides are used for killing them, but they still cause the deaths of economically valuable fish in the lakes every year. North American government agencies are tasked with controlling sea lamprey populations using a variety of methods, including pheromones and chemical sterilization. Should this large species of prehistoric lamprey be introduced into modern waterways, it could potentially become an economically significant pest like the sea lamprey.


Lampreys’ preferred food is fish, so they rarely attack humans. Scientists believe that lampreys are only dangerous when starved of their normal food sources. Even if attacks are rare, they can be alarming, and bites from such a large species as this one could be dangerous. Blood loss and tissue damage can result from an attached lamprey. Fortunately, lampreys are easy to remove because they have a critical weakness: they are fish, and need to remain in water. If bitten by a lamprey, you can exit the water, which puts the lamprey in danger of suffocation. It will detach so that it can reenter the water. Ensure that the bite area receives medical attention due to the threat of infection.

So far, this prehistoric lamprey has not yet been reported in modern water sources; it is unknown where it is being bred, but one can assume it is somewhere in the Mediterranean area. If you live in this part of the world and spot abnormally large lampreys in sources of water, report them to your fish and wildlife authorities. To prevent them from becoming invasive, techniques already practiced in the Great Lakes with sea lampreys may prove effective: sterilization of male lampreys can prevent them from breeding, and pheromones can be used as lures for the adults. More simply, but with added environmental concerns, is the use of lampricides to kill ammocoete larvae in large numbers. This is effective in exterminating lampreys, but can also harm amphibians and primitive fish such as sturgeon.

Behind the Scenes

This species is not based on any real animal. Since lampreys have cartilaginous skeletons, they do not fossilize readily, and as of 2022 only five fossil lampreys had been discovered. None of the fossil species are very large, and in fact this lamprey is larger than all known modern species. So far it has appeared only as a prop in the background of Jurassic World: Dominion.