Leiognathidae, the ponyfishes, slipmouths or slimys / slimies, are a small family of fishes in the order

Perciformes Perciformes (), also called the Acanthopteri, is an order or superorder of ray-finned fish in the clade Percomorpha. ''Perciformes'' means " perch-like". Among the well-known members of this group are perches and darters ( Percidae), and als ...

. They inhabit marine and

brackish Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuari ...

waters in the Indian and West Pacific Oceans. They can be used in the preparation of ''

bagoong ''Bagoóng'' (; ) is a Philippine condiment partially or completely made of either fermented fish (''bagoóng isdâ'') or krill or shrimp paste (''bagoóng alamáng'') with salt. The fermentation process also produces fish sauce known as ''pat ...

''.

Characteristics

Ponyfishes are small and laterally compressed in shape, with a bland, silvery colouration. They are distinguished by highly extensible mouths, and the presence of a mechanism for locking the spines in the

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...

and

anal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...

s. They also possess a highly integrated light organ in their throats that houses symbiotic bioluminescent bacteria that project light through the animal's underside. Typically, the harbored bacterium is only ''Photobacterium leiognathi'', but in the two ponyfish species ''Photopectoralis panayensis'' and ''Photopectoralis bindus'', ''Photobacterium mandapamensis'' is also present. Two of the most widely studied uses for luminescence in ponyfish are camouflage by ventral counterillumination and species-specific sexual dimorphism. The light organ systems of ponyfishes are highly variable across species and often between sexes.

Taxonomy

Leiognathidae is classified within the

suborder Order () 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 recognized ...

Percoidei Percoidei is a suborder of bony fishes in the order Perciformes. Many commercially harvested fish species are considered to be contained in this suborder, including the groupers, Serranidae, seabasses and perches. Divisions The following classif ...

by the 5th edition of ''

Fishes of the World ''Fishes of the World'' is a standard reference for the systematics of fishes. It was first written in 1976 by the American ichthyologist Joseph S. Nelson (1937–2011). Now in its fifth edition (2016), the work is a comprehensive overview of t ...

'', but they are placed in an unnamed

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

which sits outside the superfamily

Percoidea Percomorpha () is an extremely large and diverse clade of ray-finned fish. With more than 17,000 known species (including tuna, seahorses, gobies, cichlids, flatfish, wrasse, perches, anglerfish, and pufferfish) known from both marine and fresh ...

. This clade contains 7 families which appear to have some relationship to

Acanthuroidei Acanthuroidei , is a group of ray finned fishes which is a suborder of the Acanthuriformes, although older classifications regarded it as a suborder of the Perciformes, the largest order (biology), order of fish, The suborder includes the surgeonf ...

Monodactylidae Monodactylidae is a family of perciform bony fish commonly referred to as monos, moonyfishes or fingerfishes. All are strongly laterally compressed with disc-shaped bodies and tall anal and dorsal fins. Unusually for fish, scales occur on their d ...

, and

Priacanthidae The Priacanthidae, the bigeyes, are a Family (biology), family of 18 species of marine ray-finned fishes. "Catalufa (disambiguation), Catalufa" is an alternate common name for some members of the Priacanthidae. The etymology of the scientific ...

. Other authorities have placed the family in the order Chaetodontiformes alongside the family Chaetodontidae.

Timeline of genera

ImageSize = width:1000px height:auto barincrement:15px PlotArea = left:10px bottom:50px top:10px right:10px Period = from:-65.5 till:10 TimeAxis = orientation:horizontal ScaleMajor = unit:year increment:5 start:-65.5 ScaleMinor = unit:year increment:1 start:-65.5 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: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: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: -65.5 till: -55.8 color:paleocene text:

Paleocene The Paleocene ( ), or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), ...

from: -55.8 till: -33.9 color:eocene text:

Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

from: -33.9 till: -23.03 color:oligocene text:

Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...

from: -23.03 till: -5.332 color:miocene text:

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

from: -5.332 till: -2.588 color:pliocene text: Plio. from: -2.588 till: -0.0117 color:pleistocene text: Pleist. from: -0.0117 till: 0 color:holocene text: H. bar:eratop from: -65.5 till: -23.03 color:paleogene text:

Paleogene The Paleogene Period ( ; also spelled Palaeogene or Palæogene) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period Ma (million years ago) to the beginning of the Neogene Period Ma. It is the fir ...

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

Neogene The Neogene ( ,) 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 million years ago. It is the second period of th ...

from: -2.588 till: 0 color:quaternary text: Q. PlotData= align:left fontsize:M mark:(line,white) width:5 anchor:till align:left color:eocene bar:NAM1 from: -55.8 till: 0 text: Gazza color:oligocene bar:NAM2 from: -33.9 till: 0 text: Leiognathus PlotData= align:center textcolor:black fontsize:M mark:(line,black) width:25 bar:period from: -65.5 till: -55.8 color:paleocene text:

from: -55.8 till: -33.9 color:eocene text:

from: -33.9 till: -23.03 color:oligocene text:

from: -23.03 till: -5.332 color:miocene text:

from: -5.332 till: -2.588 color:pliocene text: Plio. from: -2.588 till: -0.0117 color:pleistocene text: Pleist. from: -0.0117 till: 0 color:holocene text: H. bar:era 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.

Genera

The following genera are classified within the Leiognathidae: * '' Aurigequula'' Fowler, 1918 * '' Deveximentum'' Fowler, 1904 (previously as replacement name ''Secutor ''

Gistel Gistel () is a municipality and city located in the Belgian province of West Flanders. Following local government boundary reforms in 1971 and 1977, the municipality has comprised not only Gistel, but also the towns of Moere, Snaaskerke and Z ...

, 1848) * '' Equulites'' Fowler, 1904 * ''

Eubleekeria ''Eubleekeria'' is a genus of marine ray-finned fishes, ponyfishes from the family Leiognathidae which are native to the Indian Ocean and the western Pacific Ocean. Species There are currently four recognized species in this genus: * '' Eubleek ...

'' Fowler, 1904 * '' Gazza'' Rüppell, 1835 * '' Karalla'' Chakrabarty & Sparks, 2008 * '' Leiognathus'' Lacepède, 1802 * '' Nuchequula'' Whitley, 1932 * '' Photolateralis'' Sparks & Chakrabarty, 2015 * '' Photopectoralis'' Sparks, Dunlap &

Smith Smith may refer to: People and fictional characters * Metalsmith, or simply smith, a craftsman fashioning tools or works of art out of various metals * Smith (given name) * Smith (surname), a family name originating in England ** List of people ...

, 2005

References

{{Authority control Bioluminescent fish Acanthuriformes families Extant Eocene first appearances