Aulopiformes is a diverse

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or hor ...

consisting of some 15

extant Extant is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Extant taxon, a taxon which is not extinct, ...

and several

prehistoric Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of ...

families Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Ideall ...

with about 45

genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

and over 230

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

. The common names grinners, lizardfishes and allies, or aulopiforms are sometimes used for this group. The

scientific name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

means "''Aulopus''-shaped", from ''

Aulopus ''Aulopus'' is a genus of flagfins native to the Atlantic Ocean and the Pacific Ocean. Although ''Aulopus'' is native to both the Atlantic and the Pacific oceans, for the first time in 2010 ''Aulopus filamentosus'' (the royal flagfin), was spotte ...

'' (the

type genus In biological taxonomy, the type genus is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearing type of a nominal f ...

) + the standard

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

order

suffix In linguistics, a suffix is an affix which is placed after the stem of a word. Common examples are case endings, which indicate the grammatical case of nouns, adjectives, and verb endings, which form the conjugation of verbs. Suffixes can carry ...

"-formes". It ultimately derives from

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...

''aulós'' (αὐλός, "flute" or "pipe") +

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''forma'' ("external form"), the former in reference to the elongated shape of many aulopiforms.FishBase (2000) They are grouped together because of common features in the structure of their

gill arch Branchial arches, or gill arches, are a series of bony "loops" present in fish, which support the gills. As gills are the primitive condition of vertebrates, all vertebrate embryos develop pharyngeal arches, though the eventual fate of these arc ...

es. Indeed, many authors have considered them so distinct as to warrant separation in a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

superorder Order ( la, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and ...

of the

Teleostei Teleostei (; Ancient Greek, Greek ''teleios'' "complete" + ''osteon'' "bone"), members of which are known as teleosts ), is, by far, the largest class (biology), infraclass in the class Actinopterygii, the ray-finned fishes, containing 96% of a ...

, under the name Cyclosquamata. However, monotypic taxa are generally avoided by modern

taxonomist In biology, taxonomy () is the scientific study of naming, defining ( circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxa (singular: taxon) and these groups are given ...

s if not necessary, and in this case a distinct superorder seems indeed unwarranted: together with the equally dubious superorder "

Stenopterygii Stenopterygii are a superorder of ray-finned fish in the infraclass Teleostei. Their validity is somewhat doubtful, as the group was established to separate, out of a large group of closely related Teleostei, a mere two rather peculiarly autapom ...

", the grinners appear to be so closely related to some

Protacanthopterygii Protacanthopterygii is a ray-finned fish taxon ranked as a superorder of the infraclass Teleostei. They inhabit both marine and freshwater habitats. They appear to have evolved in the Cretaceous or perhaps late Jurassic, originating probably rou ...

to be included in that superorder. In particular, this group might be the

sister taxon In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and t ...

of the

Salmoniformes Salmonidae is a family of ray-finned fish that constitutes the only currently extant family in the order Salmoniformes . It includes salmon (both Atlantic and Pacific species), trout (both ocean-going and landlocked), chars, freshwater whitefis ...

(salmon, trout, and relatives). As an alternative, the superorders are sometimes united as an unranked

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

named Euteleostei, but in that case the Protacanthopterygii would need to be split further to account for the

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

uncertainty. This would result in a highly cumbersome and taxonomically redundant group of two very small and no less than four monotypic superorders.

Description

Many aulopiforms are

deep-sea The deep sea is broadly defined as the ocean depth where light begins to fade, at an approximate depth of 200 metres (656 feet) or the point of transition from continental shelves to continental slopes. Conditions within the deep sea are a combin ...

fishes, with some

recognized as being

hermaphrodite In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrate ...

s, some with the ability to self-fertilise. Some are

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "t ...

, but most are

pelagic The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or wa ...

nekton Nekton or necton (from the ) refers to the actively swimming aquatic organisms in a body of water. The term was proposed by German biologist Ernst Haeckel to differentiate between the active swimmers in a body of water, and the passive organisms ...

. In general, aulopiform fish have a mixture of advanced and primitive characteristics relative to other

teleost Teleostei (; Greek ''teleios'' "complete" + ''osteon'' "bone"), members of which are known as teleosts ), is, by far, the largest infraclass in the class Actinopterygii, the ray-finned fishes, containing 96% of all extant species of fish. Tel ...

fish.

Aulopiforms have either a vestigial

gas bladder The swim bladder, gas bladder, fish maw, or air bladder is an internal gas-filled organ that contributes to the ability of many bony fish (but not cartilaginous fish) to control their buoyancy, and thus to stay at their current water depth w ...

, or lack it entirely, a hypaxialis muscle that is unusually extended to forward at its upper end and attaches to the

neurocranium In human anatomy, the neurocranium, also known as the braincase, brainpan, or brain-pan is the upper and back part of the skull, which forms a protective case around the brain. In the human skull, the neurocranium includes the calvaria (skull), ...

below the

spine Spine or spinal may refer to: Science Biology * Vertebral column, also known as the backbone * Dendritic spine, a small membranous protrusion from a neuron's dendrite * Thorns, spines, and prickles, needle-like structures in plants * Spine (zoolog ...

(perhaps to snap the upper part of the skull down when catching prey) and the position of the

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The t ...

ry bone. Their second

pharyngobranchial Branchial arches, or gill arches, are a series of bony "loops" present in fish, which support the gills. As gills are the primitive condition of vertebrates, all vertebrate embryos develop pharyngeal arches, though the eventual fate of these arc ...

is greatly elongated posterolaterally away from third pharyngobranchial, which lacks a

cartilaginous Cartilage is a resilient and smooth type of connective tissue. In tetrapods, it covers and protects the ends of long bones at the joints as articular cartilage, and is a structural component of many body parts including the rib cage, the neck and ...

condyle A condyle (;Entry "condyle"
in
uncinate process of the second epibranchial. Other features include the position of the

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two en ...

s far back on the body, the fused medial processes of

pelvic girdle The pelvis (plural pelves or pelvises) is the lower part of the trunk, between the abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also called bony pelvis, or pelvic skeleton). The p ...

, and the presence of an

adipose fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as s ...

(which is also typical for the Protacanthopterygii). The

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...

e of some Aulopiformes are extremely bizarre-looking, with elongated fins, and do not resemble the adult animals. They were not only described as distinct species, but also even separated as

and finally in a

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

"Macristiidae" which was allied with various Protacanthopterygii (''

sensu lato ''Sensu'' is a Latin word meaning "in the sense of". It is used in a number of fields including biology, geology, linguistics, semiotics, and law. Commonly it refers to how strictly or loosely an expression is used in describing any particular co ...

''), but the initial assessment – which found ''"Macristium"'' to resemble the deepwater lizardfishes (Bathysauridae) in some details – was not far off the mark: "''Macristium''" species are larvae of '' Bathysaurus'', while the supposed other "macristiids", "''Macristiella''" species are larvae of the deepsea tripodfish ''

Bathytyphlops ''Bathytyphlops'' is a genus of deepsea tripod fishes known only from the eastern Atlantic Ocean. Species There are currently two recognized species in this genus: * ''Bathytyphlops marionae'' Mead, 1958 (Marion's spiderfish) * ''Bathytyphlops s ...

''.

Classification

* Suborder Alepisauroidei ** Family

Alepisauridae Lancetfishes are large oceanic predatory fishes in the genus ''Alepisaurus'' ("scaleless lizard") in the monotypic taxon, monogeneric family Alepisauridae. Lancetfishes grow up to in length. Very little is known about their biology, though the ...

– lancetfishes ** Family

Anotopteridae The daggertooths (genus ''Anotopterus'') are a genus of marine mesopelagic fish in the order Aulopiformes, the sole genus of the family Anotopteridae. They are found in oceans worldwide, but prefer cooler waters. Description Daggertooths are not ...

– daggertooths (may belong in Paralepididae) ** Family

Evermannellidae Sabertooth or sabretooth fish are small, fierce-looking deep-sea aulopiform fish comprising the family Evermannellidae. The family is small, with just eight species in three genera represented; they are distributed throughout tropical to subtropi ...

– sabertooth fishes ** Family Omosudidae – hammerjaw (sometimes included in Alepisauridae) ** Family

Paralepididae Barracudinas are any member of the marine mesopelagic fish family Paralepididae: 50 or so extant species are found almost worldwide in deep waters. Several genera are known only from fossils dating back to the Ypresian epoch. The generic name ...

– barracudinas ** Family † Polymerichthyidae – an extinct alepisauroid closely related to the daggertooths and lancetfishUyeno, Teruya. "A Miocene alepisauroid fish of a new family, Polymerichthyidae, from Japan." Bull. Nat. Sci. Mus 10 (1967): 383-394. ** Family Scopelarchidae – pearleyes * Suborder Chlorophthalmoidei ** Family

Bathysauroididae ''Bathysauroides gigas'', the pale deepsea lizardfish, is the only species in the family Bathysauroididae. This species is found in the western Pacific Ocean where it is so far only known from the waters around Japan and Australia. This species ...

– pale deepsea lizardfish ** Family Bathysauropsidae – lizard greeneyes (sometimes included in Ipnopidae) ** Family

Chlorophthalmidae Greeneyes are deep-sea aulopiform marine fishes in the small family Chlorophthalmidae. Thought to have a circumglobal distribution in tropical and temperate waters, the family contains just 18 species in two genera. The family name Chlorophthalm ...

– greeneyes ** Family

Ipnopidae The Ipnopidae (deepsea tripod fishes) are a family of fishes in the order Aulopiformes. They are small, slender fishes, with maximum length ranging from about . They are found in temperate and tropical deep waters of the Atlantic, Indian, and ...

– deepsea tripodfishes ** Family Notosudidae – waryfishes * Suborder Enchodontoidei (including Halecoidei, Ichthyotringoidei, may belong in Alepisauroidei;

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

) ** Genus '' Nardorex'' (fossil, tentatively placed here) ** Genus '' Serrilepis'' (fossil, tentatively placed here) ** Genus '' Yabrudichthys'' (fossil, tentatively placed here) ** Family Apateopholidae (fossil) ** Family Cimolichthyidae (fossil) ** Family Dercetidae (fossil) ** Family Enchodontidae (fossil) ** Family Eurypholidae (fossil) ** Family

Halecidae Halecidae is an extinct family of aulopiform fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well ...

(fossil) ** Family

Ichthyotringidae Ichthyotringidae is an extinct family of aulopiform fish known from the Early to Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock st ...

(fossil) ** Family Prionolepididae (fossil) * Suborder Giganturoidei ** Family

Bathysauridae The Bathysauridae are a small family of deepwater aulopiform fish, related to the telescopefishes. The two species in the family both belong to the genus ''Bathysaurus''. Commonly called deepwater lizardfishes or deepsea lizardfishes, the latter ...

– deepwater lizardfishes ** Family Giganturidae – telescopefishes * Suborder Synodontoidei ** Family

Aulopidae The Aulopidae are a small family of aulopiform fish. They are found in most tropical and subtropical oceans, and are commonly known as flagfins. The aulopids resemble lizardfishes in appearance, and range up to in length. They have large dorsal ...

– flagfins ** Family Paraulopidae – "cucumberfishes" ** Family

Pseudotrichonotidae ''Pseudotrichonotus'' is a genus of fish in the family Pseudotrichonotidae native to the Indian and Pacific Ocean. This genus is the only member of its family. Species There are currently 4 recognized species in this genus: * ''Pseudotrichonotus ...

– sandliving lizardfishes, sand-diving lizardfishes ** Family

Synodontidae The Synodontidae or lizardfishes(or typical lizardfish to distinguish them from the Bathysauridae and Pseudotrichonotidae) are benthic (bottom-dwelling) marine and estuarine bony fishes that belong to the aulopiform fish order, a diverse group o ...

– typical lizardfishes

Timeline of genera

ImageSize = width:1000px height:auto barincrement:15px PlotArea = left:10px bottom:50px top:10px right:10px Period = from:-145.5 till:15 TimeAxis = orientation:horizontal ScaleMajor = unit:year increment:10 start:-145.5 ScaleMinor = unit:year increment:1 start:-145.5 TimeAxis = orientation:hor AlignBars = justify Colors = #legends id:CAR value:claret id:ANK value:rgb(0.4,0.3,0.196) id:HER value:teal id:HAD value:green id:OMN value:blue id:black value:black id:white value:white id:cretaceous value:rgb(0.5,0.78,0.31) id:earlycretaceous value:rgb(0.63,0.78,0.65) id:latecretaceous value:rgb(0.74,0.82,0.37) id:cenozoic value:rgb(0.54,0.54,0.258) id:paleogene value:rgb(0.99,0.6,0.32) id:paleocene value:rgb(0.99,0.65,0.37) id:eocene value:rgb(0.99,0.71,0.42) id:oligocene value:rgb(0.99,0.75,0.48) id:neogene value:rgb(0.999999,0.9,0.1) id:miocene value:rgb(0.999999,0.999999,0) id:pliocene value:rgb(0.97,0.98,0.68) id:quaternary value:rgb(0.98,0.98,0.5) id:pleistocene value:rgb(0.999999,0.95,0.68) id:holocene value:rgb(0.999,0.95,0.88) BarData= bar:eratop bar:space bar:periodtop bar:space bar:NAM1 bar:NAM2 bar:NAM3 bar:NAM4 bar:NAM5 bar:NAM6 bar:NAM7 bar:NAM8 bar:NAM9 bar:space bar:period bar:space bar:era PlotData= align:center textcolor:black fontsize:M mark:(line,black) width:25 shift:(7,-4) bar:periodtop from: -145.5 till: -99.6 color:earlycretaceous text:

Early Early may refer to: History * The beginning or oldest part of a defined historical period, as opposed to middle or late periods, e.g.: ** Early Christianity ** Early modern Europe Places in the United States * Early, Iowa * Early, Texas * Early ...

from: -99.6 till: -65.5 color:latecretaceous text:

Late Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, ...

from: -65.5 till: -55.8 color:paleocene text: Paleo. from: -55.8 till: -33.9 color:eocene text: Eo. from: -33.9 till: -23.03 color:oligocene text: Oligo. from: -23.03 till: -5.332 color:miocene text: Mio. from: -5.332 till: -2.588 color:pliocene text: Pl. from: -2.588 till: -0.0117 color:pleistocene text: Pl. from: -0.0117 till: 0 color:holocene text: H. bar:eratop from: -145.5 till: -65.5 color:cretaceous text:

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...

from: -65.5 till: -23.03 color:paleogene text:

Paleogene The Paleogene ( ; British English, also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period, geologic period and system that spans 43 million years from the end of the Cretaceous Period million yea ...

from: -23.03 till: -2.588 color:neogene text:

Neogene The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. ...

from: -2.588 till: 0 color:quaternary text: Q. PlotData= align:left fontsize:M mark:(line,white) width:5 anchor:till align:left color:latecretaceous bar:NAM1 from:-99.6 till:-97.6 text:

Nematonotus ''Nematonotus'' is an extinct genus of prehistoric bony fish that lived during the Lower Cenomanian. See also * Prehistoric fish * List of prehistoric bony fish A ''list'' is any set of items in a row. List or lists may also refer to: Pe ...

color:latecretaceous bar:NAM2 from:-99.6 till:-83.5 text: Acrognathus color:eocene bar:NAM3 from:-55.8 till:-48.6 text: Aulopopsis color:eocene bar:NAM4 from:-55.8 till:-48.6 text: Labrophagus color:eocene bar:NAM5 from:-55.8 till:0 text:

color:eocene bar:NAM6 from:-37.2 till:0 text:

Chlorophthalmus ''Chlorophthalmus'' is a genus of greeneyes Species There are currently 17 recognized species in this genus: * '' Chlorophthalmus acutifrons'' Hiyama, 1940 (Greeneye) * Shortnose greeneye (''Chlorophthalmus agassizi'') Bonaparte, 1840 (Short ...

color:eocene bar:NAM7 from:-37.2 till:0 text:

Scopelosaurus ''Scopelosaurus'' is a genus of waryfishes. The generic name is from the Greek words σκόπελος (''skopelos'', "lanternfish") and σαῦρος (''sauros'', "Atlantic horse mackerel, horse mackerel"). Species There are currently 14 recogn ...

color:oligocene bar:NAM8 from:-28.4 till:0 text: Scopelarchus color:pliocene bar:NAM9 from:-5.332 till:0 text:

Notolepis ''Notolepis'' is a genus of barracudinas. Species There are currently two recognized species in this genus: * '' Notolepis annulata'' Post Post or POST commonly refers to: *Mail, the postal system, especially in Commonwealth of Nations countri ...

PlotData= align:center textcolor:black fontsize:M mark:(line,black) width:25 bar:period from: -145.5 till: -99.6 color:earlycretaceous text:

from: -99.6 till: -65.5 color:latecretaceous text:

from: -65.5 till: -23.03 color:paleogene text:

from: -23.03 till: -2.588 color:neogene text:

from: -2.588 till: 0 color:quaternary text: Q.

Footnotes

References

* * * * * * * * {{Taxonbar, from=Q781440 Articles which contain graphical timelines Ray-finned fish orders