Fish locomotion is the various types of animal locomotion used by fish, principally by swimming. This is achieved in different groups of fish by a variety of mechanisms of propulsion, most often by wave-like lateral flexions of the fish's body and tail in the water, and in various specialised fish by motions of the fins. The major forms of locomotion in fish are:
Slimeheads, also known as roughies and redfish, are mostly small, exceptionally long-lived, deep-sea beryciform fish constituting the family Trachichthyidae. Found in temperate to tropical waters of the Atlantic, Indian, and Pacific Oceans, the family comprises about 50 species in eight genera. Slimeheads are named for the network of muciferous canals riddling their heads.
The abyssal zone or abyssopelagic zone is a layer of the pelagic zone of the ocean. The word abyss comes from the Greek word ἄβυσσος (ábussos), meaning "bottomless". At depths of 4,000–6,000 m (13,000–20,000 ft), this zone remains in perpetual darkness. It covers 83% of the total area of the ocean and 60% of Earth's surface. The abyssal zone has temperatures around 2–3 °C (36–37 °F) through the large majority of its mass. The water pressure can reach up to 76 MPa.
The common ling, also known as the white ling or simply the ling, is a large member of the family Lotidae, a group of cod-like fishes. It resembles the related rocklings, but it is much larger and has a single barbel. This species is unrelated to the pink ling, Genypterus blacodes, from the Southern Hemisphere. The common ling is found in the northern Atlantic, mainly off Europe, and into the Mediterranean Basin. It is an important quarry species for fisheries, especially in the northeastern Atlantic, although some doubts exist as to the sustainability of the fisheries. As an edible species, it is eaten fresh, frozen, or dried, but also preserved in lye, while the roe is a delicacy in Spain.
The Ipnopidae are a family of fishes in the order Aulopiformes. They are small, slender fishes, with maximum length ranging from about 10 to 40 cm. They are found in temperate and tropical deep waters of the Atlantic, Indian, and Pacific Oceans.
Helicolenus percoides, the reef ocean perch, coral cod, coral perch, Jock Stewart, kuriarki, ocean perch, red gurnard perch, red gurnard scorpionfish, red ocean perch, red perch, red rock perch, scarpee or sea perch, is a species of marine ray-finned fish belonging to the subfamily Sebastinae, part of the family Scorpaenidae. It is found in the southwestern Pacific Ocean.
The spotted ratfish is a chimaera found in the north-eastern Pacific Ocean. Often seen by divers at night in the Pacific Northwest, this cartilaginous fish gets its characteristic name from a pointed rat-like tail. The ratfish lays leathery egg cases on the bottom of muddy or sandy areas, which are often mistaken by divers as something inanimate. While mainly a deep-water species, it occurs at shallower depths in the northern part of its range. The generic name, Hydrolagus, comes from the Greek words ὕδωρ, meaning water, and λαγώς/λαγῶς, meaning hare, and the specific name honors Alexander Collie, who was a ship surgeon and early naturalist. The spotted ratfish is common in much of its range, not typically eaten by humans, and is not commercially caught.
The blackmouth catshark is a species of catshark, and part of the family Scyliorhinidae, common in the northeastern Atlantic Ocean from Iceland to Senegal, including the Mediterranean Sea. It is typically found over the continental slope at depths of 150–1,400 m (490–4,590 ft), on or near muddy bottoms. The youngest sharks generally inhabit shallower water than the older juveniles and adults. This slim-bodied species is characterized by the black interior of its mouth, a marbled pattern of pale-edged brownish saddles or blotches along its back and tail, and a prominent saw-toothed crest of enlarged dermal denticles along the upper edge of its caudal fin. It reaches lengths of 50–79 cm (20–31 in), with sharks in the Atlantic growing larger than those in the Mediterranean.
The mouse catshark is a species of catshark and part of the family Scyliorhinidae. It is common in the northeastern Atlantic Ocean from Iceland to Western Sahara. There is much taxonomic confusion regarding this species in Icelandic waters, where it may be confounded with another species of Galeus or Apristurus. Probably not exceeding 49 cm (19 in) long, the mouse catshark has a uniformly brown body and is characterized by large, rounded pelvic fins and crests of enlarged dermal denticles along both the dorsal and ventral caudal fin margins. In addition, in adult males the inner margins of the pelvic fins are merged into an "apron".
The white ghost catshark is a shark of the catshark family Scyliorhinidae found in deep water in the northeast Atlantic between latitudes 57°N and 58°N. A deep-water catshark known from the eastern North Atlantic from depths of 1,014 to 1,800 m, it is known from only a limited number of specimens. It reaches a maximum of 54 cm or 1.7 ft total length which is a medium size for the Apristurus genus.
The longhead catshark or smoothbelly catshark is a species of catshark, family Scyliorhinidae, with a patchy distribution in the Indo-Pacific from Mozambique to southern Japan to northern Australia. It is found in water between 500 and 1,140 m deep. This species grows to 59 cm (23 in) long and is characterized by its extremely long and narrow snout, short abdomen, and long anal and caudal fins. In addition, a large area of the anterior ventral portion of its body lacks dermal denticles. The longhead catshark is oviparous and the only known cartilaginous fish that is normally hermaphroditic, with the majority of individuals having both the functional reproductive organs of one sex and the undeveloped reproductive organs of the opposite sex.
A walking fish, or ambulatory fish, is a fish that is able to travel over land for extended periods of time. Some other modes of non-standard fish locomotion include "walking" along the sea floor, for example, in handfish or frogfish.
Ipnops is a genus of deep-sea fish in the family Ipnopidae, which also includes the better-known tripodfish. Ipnops are small, slender fish that live close to the ocean floor in the bathyal and abyssal zones. The genus is notable for its unusual eyes.
The popeye catalufa, also known as the bigeye soldierfish, is a species of marine ray-finned fish in the family Priacanthidae, the bigeyes. This fish has an overall dusky orange to red colour with white markings. The dorsal fin appears feathery while rest of fins have black margins. It occurs in the eastern Pacific, where it is found from Oregon to Chile. It occasionally makes its way into the aquarium trade. It grows to a size of 34 centimetres (13 in) in length. This species is nocturnal and shy, preferring deeper waters off islands. It has been recorded associating with squirrelfishes and cardinalfishes but the popeye catalufa goes as deep as 76 metres (249 ft), deeper than its associated species. This species has been recorded from rocky habitats at depths of less than 5 metres (16 ft) to over 100 metres (330 ft). It is a carnivorous species and, when kept in captivity, is known to feed on worms, crustaceans and brittle stars.
The coral hawkfish, the pixy hawkfish or sharp-headed hawkfish, is a species of marine ray-finned fish, a hawkfish belonging to the family Cirrhitidae. It is native to tropical reefs of the Indian Ocean and the Pacific Ocean. It occasionally is found in the aquarium trade.
Bathypterois is a genus of deepsea tripod fishes. They are a diverse genus that belong to the greater family Ipnopidae and order Aulopiformes. They are distinguished by having two elongated pelvic fins and an elongated caudal fin, which allow them to move and stand on the ocean floor, much like a tripod, hence the common name. Bathypterois are distributed worldwide with some particular species of the genus having specialized environmental niches, such as lower dissolved oxygen concentrations. Bathypterois have a reduced eye size, highly specified extended fins, and a mouth adapted to filter feeding. They are filter feeders whose main food source is benthopelagic planktonic calanoid copepods, but some variation is seen with maturity in secondary food sources. Bathypterois use their three elongated fins for a wide range of motion from landing to standing on the ocean floor to catching prey, for which these fins serve as specialized perceptory organs. Bathypterois have both male and female gonads at once making, them simultaneous hermaphrodites, whose gonads go through five stages of development following seasonal autumn spawning.
The flathead congoli is a species of marine ray-finned fish, belonging to the family Bovichtidae, the thornfishes or temperate icefishes. It is native to the seas off southeastern Australia. This species is the only known member of its genus.
Chionobathyscus dewitti is a species of marine ray-finned fish belonging to the family Channichthyidae, the crocodile icefishes. This species is found in the Southern Ocean.
A tripod stance is a behaviour in which quadruped animals rear up on their hind legs and use their tail to support this position. Several animals use this behaviour to improve observation or surveillance, and during feeding, grooming, thermoregulation, or fighting.
Scorpaena jacksoniensis, the Eastern red scorpionfish, Billy Bougain, cardinal scorpionfish, coral cod, coral perch, Eastern red scorpioncod, fire cod, Northern scorpionfish, ocean perch, prickly heat, red rockcod or red scorpion-cod, is a species of marine ray-finned fish belonging to the family Scorpaenidae, the scorpionfishes. It is found in the south western Pacific Ocean.
