The goblin shark ( Mitsukurina owstoni) is a rare species of deep-sea shark. Sometimes called a "living fossil", it is the only Extant taxon representative of the family Mitsukurinidae, a lineage some 125 million years old. This pink-skinned animal has a distinctive profile with an elongated, flat snout, and highly Jaw protrusion containing prominent nail-like teeth. It typically reaches a length of 3 to 4 meters (10 to 13 feet) when fully grown, although it can grow significantly larger—such as one specimen captured in 2000, which was believed to measure around 6 meters (20 feet).
Various anatomical features of the goblin shark, such as its flabby body and small fins, suggest that it is sluggish in nature. This species hunts for teleost fishes, , and near the sea floor and in the middle of the water column. Its long snout is covered with ampullae of Lorenzini that sense minute produced by nearby prey, which it can snatch up by rapidly extending its jaws. Small numbers of goblin sharks are bycatch by deepwater fisheries. The International Union for Conservation of Nature (IUCN) has assessed it as Least Concern, despite its rarity, citing its wide distribution and low incidence of capture.
Taxonomy
American
ichthyologist David Starr Jordan described the goblin shark in an 1898 issue of
Proceedings of the California Academy of Sciences, recognizing the peculiar fish not only as a new species, but also a new
genus and family. He based his account on an immature male caught in
Sagami Bay near
Yokohama, Japan. The specimen had been acquired by
shipmaster and
naturalist Alan Owston, who had given it to Professor Kakichi Mitsukuri at the University of Tokyo, who in turn brought it to Jordan. Jordan named the shark
Mitsukurina owstoni in honor of these two men.
The common name "goblin shark" is a calque of its traditional Japanese name , , a tengu being a Japanese mythical creature often depicted with a long nose and red face.
Soon after Jordan's description was published, several scientists noted the similarity between Mitsukurina and the extinct Mesozoic shark Scapanorhynchus.
Phylogeny and evolution
Phylogenetic studies based on morphology have classified the goblin shark as the most basal member of the order
Lamniformes, known as mackerel sharks.
Studies using genetic data have also confirmed a basal classification for this species.
The family Mitsukurinidae, represented by
Mitsukurina,
Scapanorhynchus, and
Anomotodon, dates back to the
Aptian age of the
Cretaceous period (
c. 125–113 Ma).
Mitsukurina itself first appears in the
fossil record during the period
Middle Eocene (
c. 49–37 Ma);
extinct species include
M. lineata and
M. maslinensis.
, which lived in warm shallow waters during the
Paleogene period (
c. 66–23 Ma), may also be a
Mitsukurina species.
As the last member of an ancient lineage, and one that retains several "primitive" traits, the goblin shark has been described as a "
living fossil".
Description
The goblin shark has a distinctively long and flat snout, resembling a blade. The proportional length of the snout decreases with age.
The eyes are small and lack protective nictitating membranes; behind the eyes are spiracles. The large mouth is
parabola in shape. The jaws are very protrusible and can be extended almost to the end of the snout, though normally held flush against the underside of the head. It has 35–53 upper and 31–62 lower tooth rows. The teeth in the main part of the jaws are long and narrow, particularly those near the symphysis (jaw midpoint), and are finely grooved lengthwise. The rear teeth near the corners of the jaw are small and have a flattened shape for crushing. Much individual variation of tooth length and width occurs, as for whether the teeth have a smaller cusplet on each side of the main cusp, and regarding the presence of toothless gaps at the symphysis or between the main and rear teeth. The five pairs of
are short, with the
inside partly exposed; the fifth pair is above the origin of the
.
The body is fairly slender and flabby. The two are similar in size and shape – both being small and rounded. The pectoral fins are also rather small and rounded. The pelvic fin and have long bases and are larger than the dorsal fins, while caudal peduncle is flattened from side-to-side and lacks keels or notches. The asymmetric caudal fin has a long upper lobe with a shallow ventral notch near the tip, and an indistinct lower lobe.
Distribution and habitat
The goblin shark has been caught in all three major oceans, indicating a wide global distribution. In the Atlantic Ocean, it has been recorded from the northern Gulf of Mexico, Suriname, French Guiana, and southern Brazil in the west, and France, Portugal,
Madeira, and Senegal in the east.
It has also been collected from
along the Mid-Atlantic Ridge.
In the
Indo-Pacific and
Oceania, it has been found off of the coasts of South Africa, Mozambique, Japan, Taiwan, Australia and New Zealand. This species has been recorded from off
East Cape to Kaikōura Canyon and from the Challenger Plateau near New Zealand.
A single eastern Pacific specimen is known, collected off southern
California.
This species is most often found over the upper continental slope at depths of .
Biology and ecology
Although observations of living goblin sharks are scant, its anatomy suggests an inactive and sluggish lifestyle.
Its skeleton is reduced and poorly
calcification, the muscle blocks along its sides (
) are weakly developed, and its fins are soft and small. Its long caudal fin, held at a low angle, is also typical of a slow-swimming shark. The long snout appears to have a sensory function, as it bears numerous ampullae of Lorenzini that
electroreception weak
produced by other animals. Due to the snout's softness, it is unlikely to be used for stirring up prey from the bottom as has been proposed.
Vision seems to be less important than other senses, considering the relatively small
optic tectum in the shark's brain.
Yet unlike most deep-sea sharks, it can change the size of its
, thus probably does use sight in some situations.
Goblin sharks may be the prey of
(
Prionace glauca).
documented from this species include the
copepod Echthrogaleus mitsukurinae,
and the
Litobothrium amsichensis and
Marsupiobothrium gobelinus.
Feeding
The goblin shark feeds mainly on deep-sea
teleost fishes such as
and
Stomiidae. It also eats
and
, including
Decapoda and
. Garbage has been recorded from the stomachs of some specimens.
Its known prey includes bottom-dwelling species such as the blackbelly rosefish (
Helicolenus dactylopterus), and midwater species such as the
squid Teuthowenia pellucida and the
ostracod Macrocypridina castanea rotunda. Thus, the goblin shark appears to forage for food both near the sea floor and far above it.
Since it is not a fast swimmer, the goblin shark may be an ambush predator. Its low-density flesh and large oily liver make it neutral buoyancy, allowing it to drift towards its prey with minimal motions so as to avoid detection.
Growth and reproduction
The reproductive behaviors of the goblin shark are poorly understood and mating has never been observed. Fishermen in Taiwan captured a pregnant female carrying six pups in 2023.
It likely shares the reproductive characteristics of other mackerel sharks, which are
viviparous with small litter sizes and
that grow during
gestation by eating undeveloped
ovum (
oophagy).
The birth size is probably close to , the length of the smallest known specimen.
Males
mature sexually at about long, while female maturation size is unknown.
No data is available concerning growth and aging.
Some researchers have estimated, based on their own research and prior findings, that male goblin sharks mature at approximately 16 years old and can live up to 60 years.
Human interactions
As a
Deep sea species, the goblin shark poses no danger to humans. After David Starr Jordan described the shark in 1898, more findings were published in 1910. "The new shark is certainly grotesque, ... the most remarkable feature is the curiously elongated nose."
A few specimens have been collected alive and brought to
, though they only survived briefly. One kept at
Tokai University lived for a week, while another at Tokyo Sea Life Park lived for two days.
Its economic significance is minimal; the meat may be dried and salted, while the jaws fetch high prices from collectors.
At one time, the Japanese used it for liver oil and
fertilizer.
This shark is not targeted by any
fisheries, but is occasionally found as
bycatch in bottom
and
, hooked on
longline fishing, or entangled in fishing gear. Most captures are isolated incidents; one of the few areas where it is caught regularly is off southern Japan, where around 30 individuals (mostly juveniles) are taken each year. A black scabbardfish (
Aphanopus carbo) fishery off
Madeira also takes two or three goblin sharks annually. During April 2003, more than a hundred goblin sharks were caught off northwestern Taiwan; the cause of the event was unknown, though observers noted it was preceded by a major
earthquake. The species had never been recorded in the area before, nor found in such numbers since.
The International Union for Conservation of Nature (IUCN) categorized the goblin shark as Least Concern.
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