| Leftvent Temporal range: [1] | |
|---|---|
 | |
| Linophryne lucifer | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Lophiiformes |
| Suborder: | Ceratioidei |
| Family: | Linophrynidae Regan, 1926 |
| Genera | |
see text | |
Leftvents are a family, the Linophrynidae, of marine ray-finned fishes which is classified within the suborder Ceratioidei, the deep sea anglerfishes. These fishes are found in the Atlantic, Indian and Pacific Oceans.
The leftvent family, Linophrynidae, was first proposed in 1926 by the English ichthyologist Charles Tate Regan as a monotypic family when he was describing specimens of previously unknown species of ceratioid fishes collected from the North Atlantic, the Caribbean Sea and the Gulf of Panama from the Danish reaearch ship, Dana . [2] The 5th edition of Fishes of the World classifies the Linophrynidae within the suborder Ceratioidei, the deep sea anglerfishes, within the order Lophiiformes, the anglerfishes. [3] Within the Certioidei this family is generally regarded the most basal. [4]
The leftvent family, Linophrynidae, is named for its type genus, Linophryne. This name prefixes linos, which means "net", an allusion Robert Collett did not explain when he proposed the genus, with phryne, meaning "toad". The prefix may be a reference to the sac like mouth hanging off the trunk, which in the holotype contained a lanternfish, like a fisherman's keep net. The second part phryne is commonly used in the names of anglerfish genera. Its use may date as far back as Aristotle and Cicero, who referred to anglerfishes as "fishing-frogs" and "sea-frogs," respectively, possibly because of their resemblance to frogs and toads. [5]
The leftvents are classified into the following genera: [6]
Lefvents are defined by the possession of one of three characteristics. These are the reduction in the number of soft rays in the median fins with the typical number in either fin being 3, they have fewer branchiostegal arches which typically number 5 and the odd location of the anus which opens to the left of the centreline of the fish. The fishes in the Linophrynidae have varied morphologies but there are some other general characteristics. In metamorphosed females have short, rather globose bodies with large heads and a very large mouth. The jaws are almost equal in length, although some species have a protruding lower jaw, with a spine on the symphysis of the lower jaw. There are also well-developed spines on the sphenotic bone, while the articular and quadrate bone have no spines. The hyomandibular has a single head, this being a feature shared with the families Neoceratiidae and Gigantactinidae. The operculum is forked with a concave rear margin, the sub opercle is long and slender and has no spines on its forward margin while the preopercle has at least one well developed spine. They have smooth, naked skin with no spinules in the skin and the teeth are very varied between genera. The illicium has a very short pterygiophore, its front end is hidden within the skin of the head or protrudes just a little above the skin on the snout. There is no relict second cephalic spine. The illicium has a length which is variable between genera, from being almost completely encased in the skin to up to 70% of the standard length. The esca has a morphology which is also highly variable between the genera. One genus. Linophryne, has a hyoid barbel that is bioluminescent. Metamorphosed females are typically dark brown to black, although the appendages of the esca, the parts of the bulb of the esca close to the tip and the hyoid barbel of Linophryne, and the fin rays have no pigmentation, with the exception of fishes in the genus Haplophryne. [7]
The metamprphosed males have very large forward pointing, rather tubular eyes with diameters that are equivalent to between 6% and 9% of the standard length. The olfactory organs are also very large and the number of olfactory lamellae varies by genera. Some genera also have teeth in the jaws of males, others do not. They usually do not have spines on the sphenotic bone and no males have a hyoid barbel and the skin is naked with no spinules, in free living males pigment may or may not be present. The parasitic males have denticular teeth, while their eyes, and olfactory organs degenerate and they have very inflated bellies. The largest published standard length of a metamorphosed female is 27.5 cm (10.8 in), that of a free-living male is 0.86 cm (0.34 in) and that of parasitic males is .073 to 3.0 cm (0.029 to 1.181 in). [7]
Leftvents are solitary anglerfishes which are found in the meso- and bathypelagic. The metamorhosed females passively lure preyusing the illlicium and esca to atttact them. The males use their highly developed sensory organs to locate females, using the denticles to bite onto the females. The males fuse to the females and become sexual parasites. [8]
When he latches onto a female the male releases enzymes to dissolve the female's tissue in the vicinity of his mouth, resulting in the male and female becoming united anatomically. After the union, the male's eyes, fins, and internal organs are lost, although the testes are retained. Its circulatory system becomes fused with the female's, and from the point of union the male receives all its nutrients through the joined blood circulation. The male stays attached to the female for the rest of her life and fertilises her spawn many times. Some species may have more than one male sexual parasite. This strategy evolved to ensure that the spawn is fertilised in the sparsely populated habiata of these deepwater anglerfishes. [9]
In other vertebrates the host's immune system would reject such a sexual parasite but in the leftvents, and other sexually parasitic anglerfish, many of the genes involved in the rejection of pathogens and foreign tissue are missing. [10]
A fossil of what may be Linophryne indica was found in Late Miocene strata of Los Angeles, California, along with a fossil of the related Borophryne apogon , during the construction of a metrorail in 1993. [11]
At least two fossils of Acentrophryne longidens have been found in Late Miocene-aged limestone from Rosedale, California. [11]
The footballfish form a family, Himantolophidae, of globose, deep-sea anglerfishes found in tropical and subtropical waters of the Atlantic, Indian, and Pacific Ocean. The family contains 23 species, all of which are classified in a single genus, Himantolophus.
Linophryne arborifera, or illuminated netdevil, is an anglerfish of the family Linophrynidae, found in all tropical and subtropical oceans at depths below 1,000 m (3,300 ft) in the Bathyal zone. Its length is up to 77 mm. The female is significantly larger than the mature, parasitic male.
Ceratiidae, the warty sea devils, caruncled seadevils or seadevils, are a family of marine ray-finned fishes belonging to the suborder Ceratioidei, the deep-sea anglerfishes, in the anglerfish order Lophiiformes. The warty sea devils are sexually dimorphic with the small males being obligate sexual parasites of the much larger females. The fishes in this family are widely distributed from polar to tropical seas around the world.
Fanfins or hairy anglerfish are a family, Caulophrynidae, of marine ray-finned fishes within the order Lophiiformes, the anglerfishes. The fishes in this family are found almost around the world in the deeper, aphotic waters of the oceans.
Oneirodidae, the dreamers are a family of marine ray-finned fishes belonging to the order Lophiiformes, the anglerfishes. These fishes are deepwater fishes found in the Atlantic, Indian and Pacific Oceans, and it is the most diverse family of fishes in the bathypelagic zone.
Thaumatichthyidae, the wolftrap anglers, is a small family of marine ray-finned fishes, also called the wolftrap seadevils, classified within the suborder Ceratioidei, the deep-sea anglerfishes. They have distinctive upper jaws with movable premaxillaries that can be lowered to form a cage-like trap around the much shorter lower jaw.
The triplewart seadevil is a species of marine ray-finned fish belonging to the family Ceratiidae, the warty sea devils, and the order Lophiiformes. This species is the only member of its genus. Noted for its extreme sexual dimorphism, the triplewart seadevil's length ranges from 20 to 30 cm for females and 1 to 3 cm for males.
Haplophryne mollis, the ghostly seadevil or soft leftvent angler, is a species of anglerfish in the family Linophrynidae and is the only species in the genus Haplophryne. It is found in the bathypelagic and mesopelagic zones of tropical and subtropical parts of the world's oceans at depths down to about 2,250 m (7,400 ft).
The horned lantern fish or prickly seadevil is a species of marine ray-finned fish, it is the only species in the monotypic family Centrophrynidae. This species has a circumglobal distribution and is distinguished from other deep-sea anglerfishes by various characters including four pectoral radials, an anterior spine on the subopercular bone, and a short hyoid (chin) barbel in both sexes.
The anglerfish are fish of the teleost order Lophiiformes. They are bony fish named for their characteristic mode of predation, in which a modified luminescent fin ray acts as a lure for other fish. The luminescence comes from symbiotic bacteria, which are thought to be acquired from seawater, that dwell in and around the sea.
Caulophryne polynema is a species of marine ray-finned fish belonging to the family Caulophrynidae, the fanfins. This species is a deepwater species which is found in the Atlantic and Pacific Oceans. Like other deepwater anglerfishes it shows extreme sexual dimorphism with the males being much smaller than the females and acting as sexual parasites of the females.
Acentrophryne is a genus of deep-sea anglerfish in the family Linophrynidae, the leftvents, known from the eastern Pacific Ocean. Fossils of the type species, A. longidens, have been found in Late Miocene strata of Rosedale, California.
Borophryne apogon, the netdevil, or greedy seadevil, is a species of leftvent anglerfish known today from the waters of the eastern Pacific Ocean off the Central American coast. It is found at depths down to around 1,750 m (5,700 ft). This species grows to a length of 8.3 centimetres (3.3 in) TL. A fossil specimen of this species has been found in the Los Angeles Basin dating back to the Late Miocene, some eight million years ago.
Linophryne, the bearded seadevils, is a genus of marine ray-finned fishes belonging to the family Linophrynidae, the leftvents. These deep sea anglerfishes are found in the Atlantic, Indian and Pacific Oceans.
Oneirodes is a genus of is a genus of marine ray-finned fish belonging to the family Oneirodidae, the dreamers, a family of deep sea anglerfishes. These predatory, deep-sea fishes are found around the world. This is the type genus, and the most speciose genus, of the family Oneirodidae. They are sexually dimorphic but, like most taxa within their family, the small males are free living and are not sexual parasites on the larger females. Only the females are used to identify the species in this genus as no species specific charaxcters have been found for males.
Linophryne algibarbata is a species of marine ray-finned fish beloning to the family Linophrynidae, the leftvents. This fish occurs im the North Atlantic Ocean.
Acentrophryne dolichonema is a species of marine ray-finned fish belonging to the family Linophrynidae, the leftvents, a family of deep sea anglerfishes. This species is only known from the eastern Pacific Ocean off the coast of Peru.
Ceratioidei, the deep-sea anglerfishes or pelagic anglerfishes, is a suborder of marine ray-finned fishes, one of four suborders in the order Lophiiformes, the anglerfishes. These fishes are found in tropical and temperate seas throughout the world. One of the better known traits of the deep-sea anglerfishes is their extreme sexual dimorphism where the males are many times smaller than the females, the males seek out females and use their sharp teeth to clamp onto the females where he remains for the rest of his life, in some species he becomes part of the female. This is the only known natural example of a process called parabiosis. Another common trait of deep-sea anglerfishes is that they use bioluminescence on their esca to attract prey in the darkness of the deep oceans they inhabit.
Acentrophryne longidens is a species of marine ray-finned fish belonging to the family Linophryidae, the leftvents, a family of deep sea anglerfishes. This species is only known from the eastern Pacific Ocean off the coast of Costa Rica and Panama.
Linophryne lucifer is a species of marine ray-finned fish belonging to the family Linophrynidae, the leftvents, a group of deep water anglerfishes. This species is found in the North Atlantic Ocean. It is the type species of the genus Linophryne.