Eleotridae is a

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

commonly known as sleeper gobies, with about 34 genera and 180

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

. Most species are found in the tropical

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

region, but there are also species in

subtropical The subtropical zones or subtropics are geographical zone, geographical and Köppen climate classification, climate zones immediately to the Northern Hemisphere, north and Southern Hemisphere, south of the tropics. Geographically part of the Ge ...

and temperate regions, warmer parts of the Americas and near the Atlantic coast in Africa. While many eleotrids pass through a

plankton Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are ca ...

ic stage in the sea and some spend their entire lives in the sea; as adults, the majority live in

freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mi ...

streams 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 ...

water. One of its genera, '' Caecieleotris'', is troglobitic. They are especially important as predators in the freshwater stream ecosystems on oceanic islands such as

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

and

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that otherwise lack the predatory fish families typical of nearby continents, such as

catfish Catfish (or catfishes; order (biology), order Siluriformes or Nematognathi) are a diverse group of ray-finned fish. Catfish are common name, named for their prominent barbel (anatomy), barbels, which resemble a cat's whiskers, though not ...

. Anatomically, they are similar to the gobies (

Gobiidae Gobiidae or gobies is a family (biology), family of bony fish in the order (biology), order Gobiiformes, one of the largest fish families comprising over 2,000 species in more than 200 genus, genera. Most of gobiid fish are relatively small, typ ...

), though unlike the majority of gobies, they do not have a pelvic sucker.Helfman, G.S., Collette, B.B. & Facey, D.E. (1997): ''The Diversity of Fishes''. Wiley-Blackwell Publishing. p. 264. Like the

true gobies True gobies were a subfamily, the Gobiinae, of the goby family (biology), family Gobiidae, although the 5th edition of the ''Fishes of the World'' does not subdivide the Gobiidae into subfamilies. They are found in all oceans and a few rivers an ...

, they are generally small fish that live on the

substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached ** Substrate (aquatic environment), the earthy material that exi ...

, often amongst

vegetation Vegetation is an assemblage of plants and the ground cover they provide. It is a general term, without specific reference to particular Taxon, taxa, life forms, structure, Spatial ecology, spatial extent, or any other specific Botany, botanic ...

, in burrows, or in crevices within rocks and

coral Corals are colonial marine invertebrates within the subphylum Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important Coral ...

reef A reef is a ridge or shoal of rock, coral, or similar relatively stable material lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic component, abiotic (non-living) processes such as deposition (geol ...

s. Although goby-like in many ways, sleeper gobies lack the pelvic fin sucker and that, together with other morphological differences, is used to distinguish the two families. The Gobiidae and Eleotridae likely share a common ancestor and they are both placed in the order

Gobiiformes Gobiiformes (meaning "goby-like") is an order of percomorph fish containing three suborders: Apogonoidei, Trichonotoidei, and Gobioidei. The order was formerly defined as containing only the gobies (now placed within the Gobioidei). However, ...

, along with a few other small families containing goby-like fishes. '' Dormitator'' and '' Eleotris'', two of the most widespread and typical genera, include a variety of species that inhabit marine,

estuarine An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...

and freshwater habitats. Among the largest members of the family are predatory species such as the bigmouth sleeper (''Gobiomorus dormitor'') at up to from freshwater near the West Atlantic region. However, most are much smaller, such as the fresh- and brackish-water species from Australia and

New Guinea New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...

, including '' Hypseleotris'', known locally as gudgeons (not to be confused with the Eurasian freshwater cyprinid '' Gobio gobio'', also known as the gudgeon and after which the Australian sleeper gobies were likely named).Riehl, R. & Baensch, H.A. (1997): ''Aquarium Atlas'' (Volume 2). Voyageur Press. p. 1216. A few of these, such as the empire gudgeon (''H. compressa'') and peacock gudgeon (''Tateurndina ocellicauda''), are sometimes kept in aquariums. The smallest in the family are the Amazonian '' Leptophilypnion'' with a

standard length Fish measurement is the measuring of individual fish and various parts of fish anatomy, their anatomies, for data used in many areas of ichthyology, including Taxonomy (biology), taxonomy and fishery biology. Overall length Standard length (SL) is ...

of less than . Fossil remains of the extinct freshwater eleotrid '' Mataichthys'' have been identified from the

Early Miocene The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages: the Aquitanian age, Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 annum, Ma to ...

of New Zealand. The extinct

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 ...

-aged genus '' Pirskenius'' from Europe has sometimes been placed in the Eleotridae, which would make it the earliest known member of the family, but more recent analyses have disputed this and support placing it in its own family.

Taxonomy

The family has been divided into three subfamilies: Butinae, Eleotrinae and Milyeringinae. However, because of the deep

divergence In vector calculus, divergence is a vector operator that operates on a vector field, producing a scalar field giving the rate that the vector field alters the volume in an infinitesimal neighborhood of each point. (In 2D this "volume" refers to ...

between the three, some authorities have recommended splitting them into separate families: Butidae, Eleotridae and Milyeringidae.Thacker, C. (2011). Systematics of Butidae and Eleotridae. ''in'' Patzner, R.; J.L. Van Tassell; and M. Kovacic. The Biology of Gobies. Verlag Science Publishers. 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 ...

follows this classification and this means that the following genera are currently included within the Eleotridae. However, the family Xenisthmidae is regarded as a

synonym A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ...

of the Eleotridae, according to the 5th Edition of Fishes of the World. * '' Allomicrodesmus'' Schultz, 1966 * '' Allomogurnda'' Allen, 2003 * '' Belobranchus'' Bleeker, 1857 * '' Bunaka'' Herre, 1927 * '' Caecieleotris''

Walsh Walsh may refer to: People and fictional characters * Walsh (surname), including a list of people and fictional characters Places Australia * Mount Walsh, Mount Walsh National Park Canada * Fort Walsh, one of the first Royal Canadian Mounted ...

& Chakrabarty, 2016 * '' Calumia''

J. L. B. Smith James Leonard Brierley Smith (26 September 1897 – 8 January 1968) was a South African ichthyology, ichthyologist, organic chemist, and university professor. He was the first to identify a taxidermied fish as a coelacanth, at the time thought t ...

, 1958 * '' Dormitator''

Gill A gill () is a respiration organ, respiratory organ that many aquatic ecosystem, aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow r ...

, 1861 * '' Eleotris''

Bloch Bloch is a surname of German origin. Notable people with this surname include: A *Adele Bloch-Bauer (1881–1925), Austrian entrepreneur *Albert Bloch (1882–1961), American painter *Alexandre Bloch (1857–1919), French painter *Alfred Bloch ( ...

& Schneider, 1801 * '' Erotelis'' Poey, 1860 * '' Giuris'' Sauvage, 1880 * '' Gobiomorphus'' Gill, 1863 * '' Gobiomorus'' Lacépède, 1800 * '' Guavina'' Bleeker, 1874 * '' Gymnoxenisthmus'' A. C. Gill, Bogorodsky & Mal, 2014 * '' Hemieleotris'' Meek &

Hildebrand Hildebrand is a character from Germanic heroic legend. ''Hildebrand'' is the modern German form of the name: in Old High German it is ''Hiltibrant'' and in Old Norse ''Hildibrandr''. The word ''hild'' means "battle" and ''brand'' means "sword" ...

, 1916 * '' Hypseleotris'' Gill, 1863 * '' Kimberleyeleotris'' Hoese & Allen, 1987 * '' Leptophilypnion'' Roberts, 2013 * '' Leptophilypnus'' Meek & Hildebrand, 1916 * '' Microphilypnus''

Myers Myers as a surname has several possible origins, e.g. Old French ("physician"), Old English ("mayor"), and Old Norse ("marsh"). People * Abram F. Myers (1889–after 1960), chair of the Federal Trade Commission and later general counsel and b ...

, 1927 * '' Mogurnda'' Gill, 1863 * '' Paraxenisthmus'' A. C. Gill & Hoese, 1993 * '' Philypnodon'' Bleeker, 1874 * '' Ratsirakia'' Maugé, 1984 * ''

Rotuma Rotuma () is a self-governing heptarchy, generally designated a Local government in Fiji, dependency of Fiji. Rotuma commonly refers to the Rotuma Island, the only permanently inhabited and by far the largest of all the islands in the Rotuma Gro ...

Springer Springer or springers may refer to: Publishers * Springer Science+Business Media, aka Springer International Publishing, a worldwide publishing group founded in 1842 in Germany formerly known as Springer-Verlag. ** Springer Nature, a multinationa ...

, 1988 * '' Tateurndina'' Nichols, 1955 * '' Tyson'' Springer, 1983 * '' Xenisthmus'' Snyder, 1908 * †'' Mataichthys'' Schwarzhans ''et al.'', 2012

References

{{Taxonbar, from=Q773959 Gobiiformes Taxa named by Charles Lucien Bonaparte