Houndfish
Encyclopedia
The houndfish, Tylosurus crocodilus, is a gamefish of the family
Belonidae. It is the largest member of its family, able to grow up to 5 feet (1.5 m) and reach 10 pounds (4.5 kg). It is also often called the Crocodile Needlefish.
s, its dorsal fin
has 21–25 soft rays, and its anal fin has 19–22. They are also known to have 80–86 vertebrae. A key way of distinguishing the houndfish from other members of the Tylosurus genus is that the houndfish's teeth
point anteriorly when the fish is a juvenile. The teeth of other species are straight at all ages. The houndfish also has a more stout, cylindrical
body and a shorter head than other needlefish
es. They have dark blue backs and silver-white sides and are plain white ventrally. A houndfish has a distinct keel
on the caudal peduncle, and the caudal fin itself is deeply forked. Juvenile houndfish possess an elevated, black lobe on the posterior of their dorsal fins. The longest recorded houndfish was 150 centimetres (4.9 ft), and the largest recorded weight was 6.35 kilograms (14 lb).
and Pacific Ocean
s, houndfish are found in the Red Sea
and from the coast
of South Africa
, east to French Polynesia
, and north to Japan
, and south to New South Wales
, Australia
. Its usual subspecies
, T. c. crocodilus is replaced by T. c. fodiator, also called the Mexican needlefish, in the eastern Pacific. The Mexican needlefish is found only in the eastern Pacific, from the Gulf of California
south to Panama
, including the area off Cocos Island
. In the Atlantic Ocean
, houndfish are known from New Jersey
to Brazil
in the east, and in the west, they are found from Fernando Poo, Cameroon
, and Liberia
to Ascension Island
. Houndfish can also be found near Guinea
, Senegal
and Cape Verde
.
A pelagic animal, houndfish can be found over lagoon
s and seaward reef
s either as individuals or small groups, where they feed mainly on smaller fishes. Houndfish lay egg
s which attach themselves to objects in the water via tendril
s on the surface of each egg
.
Considered a gamefish, houndfish can be caught by use of artificial lights, similar to other needlefishes. Although they are considered good to eat, and usually sold fresh, the market is small because houndfish flesh has a greenish color similar to the Flat needlefish
. Houndfish are considered somewhat dangerous and are feared by fishermen because of their size and tendency to leap out of the water, causing puncture wounds
with their beaks, when frightened or attracted to the very lights used to catch them.
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Belonidae. It is the largest member of its family, able to grow up to 5 feet (1.5 m) and reach 10 pounds (4.5 kg). It is also often called the Crocodile Needlefish.
Description
While the houndfish has no spineSpine (zoology)
A spine is a hard, thorny or needle-like structure which occurs on various animals. Animals such as porcupines and sea urchins grow spines as a self-defense mechanism. Spines are often formed of keratin...
s, its dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
has 21–25 soft rays, and its anal fin has 19–22. They are also known to have 80–86 vertebrae. A key way of distinguishing the houndfish from other members of the Tylosurus genus is that the houndfish's teeth
Tooth
Teeth are small, calcified, whitish structures found in the jaws of many vertebrates that are used to break down food. Some animals, particularly carnivores, also use teeth for hunting or for defensive purposes. The roots of teeth are embedded in the Mandible bone or the Maxillary bone and are...
point anteriorly when the fish is a juvenile. The teeth of other species are straight at all ages. The houndfish also has a more stout, cylindrical
Cylinder (geometry)
A cylinder is one of the most basic curvilinear geometric shapes, the surface formed by the points at a fixed distance from a given line segment, the axis of the cylinder. The solid enclosed by this surface and by two planes perpendicular to the axis is also called a cylinder...
body and a shorter head than other needlefish
Needlefish
Needlefish are piscivorous fishes primarily associated with very shallow marine habitats or the surface of the open sea. Some genera include species found in marine, brackish, and freshwater environments while a few genera are confined to freshwater rivers and streams, including Belonion,...
es. They have dark blue backs and silver-white sides and are plain white ventrally. A houndfish has a distinct keel
Fish anatomy
Fish anatomy is primarily governed by the physical characteristics of water, which is much denser than air, holds a relatively small amount of dissolved oxygen, and absorbs more light than air does.- Body :...
on the caudal peduncle, and the caudal fin itself is deeply forked. Juvenile houndfish possess an elevated, black lobe on the posterior of their dorsal fins. The longest recorded houndfish was 150 centimetres (4.9 ft), and the largest recorded weight was 6.35 kilograms (14 lb).
Distribution and habitat
In the IndianIndian 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...
and Pacific Ocean
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...
s, houndfish are found in 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...
and from the coast
Coast
A coastline or seashore is the area where land meets the sea or ocean. A precise line that can be called a coastline cannot be determined due to the dynamic nature of tides. The term "coastal zone" can be used instead, which is a spatial zone where interaction of the sea and land processes occurs...
of South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
, east to French Polynesia
French Polynesia
French Polynesia is an overseas country of the French Republic . It is made up of several groups of Polynesian islands, the most famous island being Tahiti in the Society Islands group, which is also the most populous island and the seat of the capital of the territory...
, and north to 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 south to 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...
. Its usual subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
, T. c. crocodilus is replaced by T. c. fodiator, also called the Mexican needlefish, in the eastern Pacific. The Mexican needlefish is found only in the eastern Pacific, from the Gulf of California
Gulf of California
The Gulf of California is a body of water that separates the Baja California Peninsula from the Mexican mainland...
south to Panama
Panama
Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...
, including the area off Cocos Island
Cocos Island
Cocos Island is an uninhabited island located off the shore of Costa Rica . It constitutes the 11th district of Puntarenas Canton of the province of Puntarenas. It is one of the National Parks of Costa Rica...
. In the Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
, houndfish are known from New Jersey
New Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
to Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
in the east, and in the west, they are found from Fernando Poo, Cameroon
Cameroon
Cameroon, officially the Republic of Cameroon , is a country in west Central Africa. It is bordered by Nigeria to the west; Chad to the northeast; the Central African Republic to the east; and Equatorial Guinea, Gabon, and the Republic of the Congo to the south. Cameroon's coastline lies on the...
, and Liberia
Liberia
Liberia , officially the Republic of Liberia, is a country in West Africa. It is bordered by Sierra Leone on the west, Guinea on the north and Côte d'Ivoire on the east. Liberia's coastline is composed of mostly mangrove forests while the more sparsely populated inland consists of forests that open...
to Ascension Island
Ascension Island
Ascension Island is an isolated volcanic island in the equatorial waters of the South Atlantic Ocean, around from the coast of Africa and from the coast of South America, which is roughly midway between the horn of South America and Africa...
. Houndfish can also be found near Guinea
Guinea
Guinea , officially the Republic of Guinea , is a country in West Africa. Formerly known as French Guinea , it is today sometimes called Guinea-Conakry to distinguish it from its neighbour Guinea-Bissau. Guinea is divided into eight administrative regions and subdivided into thirty-three prefectures...
, Senegal
Senegal
Senegal , officially the Republic of Senegal , is a country in western Africa. It owes its name to the Sénégal River that borders it to the east and north...
and Cape Verde
Cape Verde
The Republic of Cape Verde is an island country, spanning an archipelago of 10 islands located in the central Atlantic Ocean, 570 kilometres off the coast of Western Africa...
.
A pelagic animal, houndfish can be found over 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,...
s and seaward reef
Reef
In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water ....
s either as individuals or small groups, where they feed mainly on smaller fishes. Houndfish lay egg
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
s which attach themselves to objects in the water via tendril
Tendril
In botany, a tendril is a specialized stem, leaf or petiole with a threadlike shape that is used by climbing plants for support, attachment and cellular invasion by parasitic plants, generally by twining around suitable hosts. They do not have a lamina or blade, but they can photosynthesize...
s on the surface of each egg
.
Relationship to humans
Flat needlefish
The flat needlefish, Ablennes hians, the only known member of the genus Ablennes, is a marine fish of the family Belonidae. Flat needlefish are considered gamefish, frequently caught with the help of artificial lights, but are not often eaten because of their green-colored...
. Houndfish are considered somewhat dangerous and are feared by fishermen because of their size and tendency to leap out of the water, causing puncture wounds
Wound
A wound is a type of injury in which skin is torn, cut or punctured , or where blunt force trauma causes a contusion . In pathology, it specifically refers to a sharp injury which damages the dermis of the skin.-Open:...
with their beaks, when frightened or attracted to the very lights used to catch them.