Inimicus
Encyclopedia
Inimicus is a genus
of venomous
fishes, closely related to the true stonefish
es. This genus is a member of the Synanceiidae (devilfishes, goblinfishes, and stonefishes) family of the Scorpaeniformes
order of ray-finned fish
es. These benthic fishes are found on sandy or silty substrates
of lagoon
and seaward reefs
, in coastal regions of tropical
oceans. The ten described species are collectively known by various common names, including Ghoul, Goblinfish, Sea Goblin, Spiny devilfish, Stinger, and Stingfish).
NE: Not Evaluated
Species no longer recognized:
oceans. Their range does however extend a little into the subtropical
zone. The waters of the Red Sea
off the coast of Egypt
appear to mark the westernmost limit of their range, while specimens have been reported as far to the east as New Caledonia
. The northern coast of New South Wales
, Australia
marks the southernmost extent of their range, which extends as far to the north as Japan. Inimicus are benthic fishes, living mainly on the bottom of mangrove
swamps and coral reefs, at depths between 5 and 450 meters.
s. The body color can be a dull yellow, gray, brown, or rust in color with light blotches, and very similar to that of the surrounding sandy or coral seabed in which they are found. This coloration acts as a camouflage
which renders them extremely difficult to detect in their natural habitat. The skin is without scales except along the lateral line
, and is covered with venomous spines and wartlike glands which give it a knobby appearance. The head is flattened, depressed and concave. The eyes, mouth and nostrils project upwards and outwards from the dorsal aspect of the head. Sexual dimorphism
is not believed to occur in this genus.
Fin morphology:
ambush predator
s. They are nocturnal and typically lie partially buried on the sea floor or on a coral head during the day, covering themselves with sand and other debris to further camouflage themselves. They have no known natural predators. When threatened, they spread their brilliantly colored pectoral and caudal fins as a warning. Once dug in, they are very reluctant to leave their hiding places. When they do move, they display an unusual mechanism of subcarangiform locomotion---they crawl slowly along the seabed, employing the four lower rays (two on each side) of their pectoral fins as legs.
The paired pectoral fins of these fishes are a remarkable example of their adaptation to life in a benthic environment. No longer useful or necessary for aiding the animal in maneuvering within the water column, the fins have taken on a number of other functions useful to life as a demersal fish. Among these include probing for food items, propping the forward part of the body away from the bottom, and the aforementioned subcarangiform locomotion.
Inimicus is not the only fish that demonstrate this type of ambulation; it has been extensively described in other related benthic Scorpaeniformes fish such as the Sea robin
, Flying gurnards
, and the Tub Gurnard
, Chelidonichthys lucerna. This type of locomotion, based on voluntary and coordinated movements of paired pectoral fins, is believed by some to be a precursor to the later development of similar ambulation in terrestrial vertebrates.
s at the bases of needle-like spines in their dorsal fins. Upon contact with the dorsal fin, the fish can deliver a very painful, potentially fatal, sting. The venom consists of a mixture of proteolytic enzyme
s, including stonustoxin (a hemotoxin
), trachynilysin (a neurotoxin
), and cardioleputin (a cardiotoxin
). Envenomation
results severe and immediate local pain, sometimes followed by shock, paralysis, tissue necrosis
, and even death.
Despite the obvious risks, one species of Inimicus, I. japonicum, is commercially cultured
in Japan. It is used as a food fish there, and it also has applications in Chinese medicine
.
toxoid vaccine should also be administered, if indicated. Surviving victims often suffer localized tissue necrosis and nerve damage, leading to atrophy of adjoining muscle tissues.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of venomous
Venomous fish
Venomous fish are fish that produce venom. There are at least 1200 species of venomous fish, and they include the Stonefish, Lionfish, Scorpion Fish, Stargazer, and Toadfish .-See also:* Hallucinogenic fish...
fishes, closely related to the true stonefish
Synanceia
Synanceia is a genus of fish of the family Synanceiidae, the Stonefishes, whose members are venomous, dangerous, and even fatal to humans. It is the most venomous fish in the world. They are found in the coastal regions of Indo-Pacific oceans....
es. This genus is a member of the Synanceiidae (devilfishes, goblinfishes, and stonefishes) family of the Scorpaeniformes
Scorpaeniformes
Scorpaeniformes is an order of ray-finned fish, but it has also been called the Scleroparei.They are known as "mail-cheeked" fishes due to their distinguishing characteristic, the suborbital stay: a backwards extension of the third circumorbital bone across the cheek to the preoperculum, to which...
order of ray-finned fish
Actinopterygii
The Actinopterygii or ray-finned fishes constitute a class or sub-class of the bony fishes.The ray-finned fishes are so called because they possess lepidotrichia or "fin rays", their fins being webs of skin supported by bony or horny spines , as opposed to the fleshy, lobed fins that characterize...
es. These benthic fishes are found on sandy or silty substrates
Substrate (marine biology)
Stream substrate is the material that rests at the bottom of a stream. There are several classification guides. One is:*Mud – silt and clay.*Sand – Particles between 0.06 and 2 mm in diameter.*Granule – Between 2 and 4 mm in diameter....
of lagoon
Lagoon
A lagoon is a body of shallow sea water or brackish water separated from the sea by some form of barrier. The EU's habitat directive defines lagoons as "expanses of shallow coastal salt water, of varying salinity or water volume, wholly or partially separated from the sea by sand banks or shingle,...
and seaward reefs
Coral reef
Coral reefs are underwater structures made from calcium carbonate secreted by corals. Coral reefs are colonies of tiny living animals found in marine waters that contain few nutrients. Most coral reefs are built from stony corals, which in turn consist of polyps that cluster in groups. The polyps...
, in coastal regions of tropical
Tropics
The tropics is a region of the Earth surrounding the Equator. It is limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately N and the Tropic of Capricorn in the southern hemisphere at S; these latitudes correspond to the axial tilt of the Earth...
oceans. The ten described species are collectively known by various common names, including Ghoul, Goblinfish, Sea Goblin, Spiny devilfish, Stinger, and Stingfish).
Species
The members of the Inimicus genus are nearly identical in appearance and behavior, and often confused with one another. As of 2010, ten species are included in the genus Inimicus:| Species | Common name | Habitat | Distribution | IUCN status |
|---|---|---|---|---|
| Inimicus brachyrhynchus | Marine; tropical; reef-dwelling; demersal | Western Central Pacific | NE* | |
| Inimicus caledonicus | Chinese ghoul, Caledonian stinger, Demon stinger | Marine; tropical; reef-dwelling; demersal | Eastern Indian Ocean Indian Ocean The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and... : Andaman Andaman Islands The Andaman Islands are a group of Indian Ocean archipelagic islands in the Bay of Bengal between India to the west, and Burma , to the north and east... and Nicobar Nicobar Islands The Nicobar Islands are an archipelagic island chain in the eastern Indian Ocean... islands. Western Pacific Pacific Ocean The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World... : Australia Australia Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area... , Papua New Guinea Papua New Guinea Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands... and New Caledonia New Caledonia New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of... . |
NE |
| Inimicus cuvieri | Marine; tropical; reef-dwelling; demersal | Western Pacific: South China Sea South China Sea The South China Sea is a marginal sea that is part of the Pacific Ocean, encompassing an area from the Singapore and Malacca Straits to the Strait of Taiwan of around... |
NE | |
| Inimicus didactylus Inimicus didactylus Inimicus didactylus, also known as Demon Stinger or Devil Stinger, is a member of the Inimicus genus of venomous fishes, closely related to the true stonefishes. It can reach a body length of 25 cm and is irregularly surfaced with spines and a knobby appearance. The fish has venomous spines... |
Goblinfish, Popeyed sea goblin, Demon stinger, Devil stinger, Longsnout stinger, Spiny devilfish, Bearded ghoul | Marine; tropical; reef-dwelling; demersal | Eastern Indian and Western Pacific oceans | NE |
| Inimicus filamentosus Inimicus filamentosus Inimicus filamentosus, also known as the Filament-finned stinger, Barred ghoul, Two-stick stingfish, or Devil scorpionfish, is a member of the Inimicus genus of venomous fishes. It is a member of the Synanceiidae family of the Scorpaeniformes order of ray-finned fishes... |
Filament-finned stinger, Barred ghoul, Two-stick stingfish, Devil scorpionfish | Marine; tropical; reef-dwelling; demersal | Western Indian Ocean: Red Sea Red Sea The Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait and the Gulf of Aden. In the north, there is the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez... and East Africa East Africa East Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:... to Maldives Maldives The Maldives , , officially Republic of Maldives , also referred to as the Maldive Islands, is an island nation in the Indian Ocean formed by a double chain of twenty-six atolls oriented north-south off India's Lakshadweep islands, between Minicoy Island and... |
NE |
| Inimicus gruzovi | Marine; tropical; reef-dwelling; demersal | Western Central Pacific | NE | |
| Inimicus japonicus | Devil stinger | Marine; tropical; reef-dwelling; demersal | Indo-West Pacific: Japan Japan Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south... and East China Sea East China Sea The East China Sea is a marginal sea east of China. It is a part of the Pacific Ocean and covers an area of 1,249,000 km² or 750,000 square miles.-Geography:... |
NE |
| Inimicus joubini | Marine; tropical; reef-dwelling; demersal | Northwest Pacific: Japan and Vietnam Vietnam Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –... |
NE | |
| Inimicus sinensis Inimicus sinensis Inimicus sinensis, also known as the Spotted ghoul, Chinese stinger, Spotted stingerfish, or Spotted stonefish, is a member of the Inimicus genus of venomous fishes. It is a member of the Synanceiidae family of the Scorpaeniformes order of ray-finned fishes... |
Spotted ghoul, Spotted stonefish | Marine; tropical; reef-dwelling; demersal | NE | |
| Inimicus smirnovi | Marine; tropical; reef-dwelling; demersal | Western Central Pacific | NE | |
NE: Not Evaluated
Species no longer recognized:
- Inimicus barbatus has been reclassified as Inimicus caledonicus
- Inimicus dactylus has been reclassified as Inimicus filamentosus
Geographic distribution
Members of the Inimicus genus are distributed mainly in warm tropical waters in the coastal regions of Indo-PacificIndo-Pacific
The Indo-Pacific is a biogeographic region of the Earth's seas, comprising the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in the general area of Indonesia...
oceans. Their range does however extend a little into the subtropical
Subtropics
The subtropics are the geographical and climatical zone of the Earth immediately north and south of the tropical zone, which is bounded by the Tropic of Cancer and the Tropic of Capricorn, at latitudes 23.5°N and 23.5°S...
zone. The waters of the Red Sea
Red Sea
The Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait and the Gulf of Aden. In the north, there is the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez...
off the coast of Egypt
Egypt
Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...
appear to mark the westernmost limit of their range, while specimens have been reported as far to the east as New Caledonia
New Caledonia
New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...
. The northern coast of New South Wales
New South Wales
New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...
, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
marks the southernmost extent of their range, which extends as far to the north as Japan. Inimicus are benthic fishes, living mainly on the bottom of mangrove
Mangrove
Mangroves are various kinds of trees up to medium height and shrubs that grow in saline coastal sediment habitats in the tropics and subtropics – mainly between latitudes N and S...
swamps and coral reefs, at depths between 5 and 450 meters.
Description
Adults are typically 13-25 centimeters in length, and can weigh up to 480 gramGram
The gram is a metric system unit of mass....
s. The body color can be a dull yellow, gray, brown, or rust in color with light blotches, and very similar to that of the surrounding sandy or coral seabed in which they are found. This coloration acts as a camouflage
Camouflage
Camouflage is a method of concealment that allows an otherwise visible animal, military vehicle, or other object to remain unnoticed, by blending with its environment. Examples include a leopard's spotted coat, the battledress of a modern soldier and a leaf-mimic butterfly...
which renders them extremely difficult to detect in their natural habitat. The skin is without scales except along the lateral line
Lateral line
The lateral line is a sense organ in aquatic organisms , used to detect movement and vibration in the surrounding water. Lateral lines are usually visible as faint lines running lengthwise down each side, from the vicinity of the gill covers to the base of the tail...
, and is covered with venomous spines and wartlike glands which give it a knobby appearance. The head is flattened, depressed and concave. The eyes, mouth and nostrils project upwards and outwards from the dorsal aspect of the head. Sexual dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
is not believed to occur in this genus.
Fin morphology:
- dorsal finDorsal finA dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
: composed of 15 to 17 spines and 7 to 9 soft rays. - caudal fin: composed of 2-4 spines and 4-14 soft rays, with dark bands at basal and subterminal positions.
- pelvic fin: composed of one spine and 3-5 soft rays.
- pectoral fin: composed of 10-12 rays. The two most caudal rays of each pectoral fin are detached from the rest of the fin, and angled in a ventral direction. The fish employ these two rays to prop up the forward part of their body, as well as to "walk" along the bottom of the substrate. The ventral surface of the pectoral fins bears broad black bands containing smaller, lighter spots at the basal and distal ends. In I. filamentosus, these bands are attenuated, while the bands of I. sinensis have yellow spots on them. This is a key feature for distinguishing the two species, which are otherwise nearly identical.
Behavior
Inimicus are piscivorousPiscivore
A piscivore is a carnivorous animal which eats primarily fish. Piscivory was the diet of early tetrapods , insectivory came next, then in time reptiles added herbivory....
ambush predator
Ambush predator
Ambush predators or sit-and-wait predators are carnivorous animals that capture prey by stealth or cunning, not by speed or necessarily by strength. These organisms usually hide motionless and wait for prey to come within striking distance. They are often camouflaged, and may be solitary...
s. They are nocturnal and typically lie partially buried on the sea floor or on a coral head during the day, covering themselves with sand and other debris to further camouflage themselves. They have no known natural predators. When threatened, they spread their brilliantly colored pectoral and caudal fins as a warning. Once dug in, they are very reluctant to leave their hiding places. When they do move, they display an unusual mechanism of subcarangiform locomotion---they crawl slowly along the seabed, employing the four lower rays (two on each side) of their pectoral fins as legs.
The paired pectoral fins of these fishes are a remarkable example of their adaptation to life in a benthic environment. No longer useful or necessary for aiding the animal in maneuvering within the water column, the fins have taken on a number of other functions useful to life as a demersal fish. Among these include probing for food items, propping the forward part of the body away from the bottom, and the aforementioned subcarangiform locomotion.
Inimicus is not the only fish that demonstrate this type of ambulation; it has been extensively described in other related benthic Scorpaeniformes fish such as the Sea robin
Sea robin
Sea robins, also known as gurnard, are bottom-feeding scorpaeniform fishes in the family Triglidae. They get their name from their large pectoral fins, which, when swimming, open and close like a bird's wings in flight....
, Flying gurnards
Dactylopteridae
The flying gurnards are a family, Dactylopteridae, of marine fish notable for their greatly enlarged pectoral fins. As they cannot literally fly, an alternative name preferred by some authors is helmet gurnards...
, and the Tub Gurnard
Tub Gurnard
The tub gurnard, Chelidonichthys lucerna is a species of bottom-dwelling coastal fish with a spiny armored head and fingerlike pectoral fins used for crawling along the sea bottom...
, Chelidonichthys lucerna. This type of locomotion, based on voluntary and coordinated movements of paired pectoral fins, is believed by some to be a precursor to the later development of similar ambulation in terrestrial vertebrates.
Relevance to humans
Like all known members of the family Synanceiidae, all members of the genus Inimicus possess a complex and extremely potent venom. It is stored in glandGland
A gland is an organ in an animal's body that synthesizes a substance for release of substances such as hormones or breast milk, often into the bloodstream or into cavities inside the body or its outer surface .- Types :...
s at the bases of needle-like spines in their dorsal fins. Upon contact with the dorsal fin, the fish can deliver a very painful, potentially fatal, sting. The venom consists of a mixture of proteolytic enzyme
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
s, including stonustoxin (a hemotoxin
Hemotoxin
Hemotoxins, haemotoxins or hematotoxins are toxins that destroy red blood cells , disrupt blood clotting, and/or cause organ degeneration and generalized tissue damage. The term hemotoxin is to some degree a misnomer since toxins that damage the blood also damage other tissues...
), trachynilysin (a neurotoxin
Neurotoxin
A neurotoxin is a toxin that acts specifically on nerve cells , usually by interacting with membrane proteins such as ion channels. Some sources are more general, and define the effect of neurotoxins as occurring at nerve tissue...
), and cardioleputin (a cardiotoxin
Cardiotoxicity
Cardiotoxicity is the occurrence of heart electrophysiology dysfunction or/and muscle damage. The heart becomes weaker and is not as efficient in pumping and therefore circulating blood...
). Envenomation
Envenomation
Envenomation is the process by which venom is injected into some animal by the bite of a venomous animal. Many kinds of animals, including mammals , reptiles , spiders , insects , employ venom for hunting and for self defense...
results severe and immediate local pain, sometimes followed by shock, paralysis, tissue necrosis
Necrosis
Necrosis is the premature death of cells in living tissue. Necrosis is caused by factors external to the cell or tissue, such as infection, toxins, or trauma. This is in contrast to apoptosis, which is a naturally occurring cause of cellular death...
, and even death.
Despite the obvious risks, one species of Inimicus, I. japonicum, is commercially cultured
Fish farming
Fish farming is the principal form of aquaculture, while other methods may fall under mariculture. Fish farming involves raising fish commercially in tanks or enclosures, usually for food. A facility that releases young fish into the wild for recreational fishing or to supplement a species'...
in Japan. It is used as a food fish there, and it also has applications in Chinese medicine
Traditional Chinese medicine
Traditional Chinese Medicine refers to a broad range of medicine practices sharing common theoretical concepts which have been developed in China and are based on a tradition of more than 2,000 years, including various forms of herbal medicine, acupuncture, massage , exercise , and dietary therapy...
.
Treatment of envenomation
Envenomation by Inimicus species is characterized by immediate and severe local pain. Medical aid must be sought at the earliest opportunity after envenomation. Recommended first aid treatment includes immersion of the affected area in hot water. Immersing the injured area in water at a temperature of at least 45 °C (113 °F) can partially denature the proteolytic enzymes in the venom. Some relief can also be obtained by infiltrating the envenomation site with a local anesthetic. For more extreme cases, an intramuscular injection of a specific horse-derived antivenom can be lifesaving. TetanusTetanus
Tetanus is a medical condition characterized by a prolonged contraction of skeletal muscle fibers. The primary symptoms are caused by tetanospasmin, a neurotoxin produced by the Gram-positive, rod-shaped, obligate anaerobic bacterium Clostridium tetani...
toxoid vaccine should also be administered, if indicated. Surviving victims often suffer localized tissue necrosis and nerve damage, leading to atrophy of adjoining muscle tissues.
Gallery
Click here to see more photographs of various specimens of the Inimicus genus.External links
- Zipcodezoo.com: Inimicus genus