Pacific ladyfish | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Elopiformes |
Family: | Elopidae |
Genus: | Elops |
Species: | E. affinis |
Binomial name | |
Elops affinis Regan, 1909 | |
The Pacific ladyfish (Elops affinis), also known as the Pacific tenpounder and machete, is a species of ray-finned fish in the genus Elops , the only genus in the monotypic family Elopidae. The Pacific ladyfish can be found throughout the southwest U.S. and other areas in the Pacific Ocean. [2] [3] [4] [5] [6]
The Pacific ladyfish have very round bodies with terminal mouths, and profound gill formations known as pseudobranchiae. They have a larger number of dorsal fin rays than most Arizona fish, [5] with numbers ranging from 27 to 35. Anal fin rays usually range from 13 to 19, and they have 12 to 16 pelvic rays. This species is very different from most chordates in that it has no conus arteriosus, a tendinous band of tissue from which the pulmonary artery arises. Because of this absence, they have a much smaller pulmonary artery. This fish's lateral lines are unbranched, and lateral line scales are usually within ranges of 95 to 120. All scales are silvery and cycloid, along with the overall color of the fish; however, yellow pigment can occur in the eyes. Some aids to identification include the prominent auxiliary and inguinal processes. [4]
This species is restricted primarily to the Southwest United States. [4] Most records come from the Colorado River Delta and the Gulf of California, as they spawn here and then travel southwest into Arizona. They were also common in the Salton Sea in California, but their numbers have been slowly declining. During floods, Pacific ladyfish enter the Lower Colorado River from the Gulf. They can be found in Yuma Colorado River portions, with records as far south as certain Mexican dams. Pacific tenpounders are primarily a marine form, meaning they require a higher salinity water content then most freshwater fish. Because of this, they have evolved efficient swimming techniques allowing them to swim in lagoons and estuaries with higher salinities. Their maximum depth is around 10 m (33 ft). [3]
This species uses a wide range of water salinities when spawning. Under normal conditions, the Pacific tenpounder are located in brackish water, but they travel deep into oceanic, salty waters for breeding. They place their eggs far from shore in more planktonic regions to provide them with nutrients as juveniles. [2] The larvae look like eels at birth, but their forked tails distinguish them. Their young usually feed on the crustaceans in the brackish or coastal waters. This may explain their instinct to move from the Gulf of California into the Lower Colorado during flood conditions. [4]
Pacific ladyfish are pelagic, marine forms preferring either brackish or fresh water unless they are breeding. They prefer specific water depths of no more than 8 m (26 ft). Little is known about the ecology of this species, but they are known to be highly carnivorous, feeding on smaller fish and crustaceans. [2] This behavior is very similar to their relative, the Atlantic ladyfish. Maximum size is relatively larger than most Arizona fish, reaching lengths of 1 m (3 ft 3 in). A negative correlation exists between size and presence in the Colorado River. As they become larger in size, they enter more brackish waters for unknown reasons. Larval and juvenile stages of fish have large records of distribution near Rocky Point, in the Sea of Cortez tidal inlets. Their spawning areas are usually closer to coastal areas, because they use saltier waters for their young. [4]
This species uses estuarine areas and hypersaline lagoons; changes in the quality of these habitats may affect this species' population dynamics. Although this species may not be closely associated with any single habitat, it may be adversely affected by development and urbanization. [7]
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 and fresh water together, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root brak. Certain human activities can produce brackish water, in particular civil engineering projects such as dikes and the flooding of coastal marshland to produce brackish water pools for freshwater prawn farming. Brackish water is also the primary waste product of the salinity gradient power process. Because brackish water is hostile to the growth of most terrestrial plant species, without appropriate management it can be damaging to the environment.
The Gulf of California, also known as the Sea of Cortés or Sea of Cortez, or less commonly as the Vermilion Sea, is a marginal sea of the Pacific Ocean that separates the Baja California peninsula from the Mexican mainland. It is bordered by the states of Baja California, Baja California Sur, Sonora, and Sinaloa with a coastline of approximately 4,000 km (2,500 mi). Rivers that flow into the Gulf of California include the Colorado, Fuerte, Mayo, Sinaloa, Sonora, and the Yaqui. The surface of the gulf is about 160,000 km2 (62,000 sq mi). Maximum depths exceed 3,000 meters (9,800 ft) because of the complex geology, linked to plate tectonics.
The Elopiformes are the order of ray-finned fish including the tarpons, tenpounders, and ladyfish, as well as a number of extinct types. They have a long fossil record, easily distinguished from other fishes by the presence of an additional set of bones in the throat.
The Elopidae are a family of ray-finned fish containing a single living genus Elops. They are commonly known as ladyfish, skipjacks, jack-rashes, or tenpounders.
The ladyfish or tenpounder is a species of fish in the genus Elops, the only genus in the monotypic family Elopidae.
The crevalle jack, also known as the common jack, black-tailed trevally, couvalli jack, black cavalli, jack crevale, or yellow cavalli is a common species of large marine fish classified within the jack family, Carangidae. The crevalle jack is distributed across the tropical and temperate waters of the Atlantic Ocean, ranging from Nova Scotia, Canada to Uruguay in the western Atlantic and Portugal to Angola in the eastern Atlantic, including the Mediterranean Sea. It is distinguishable from similar species by its deep body, fin colouration and a host of more detailed anatomical features, including fin ray and lateral line scale counts. It is one of the largest fish in the genus Caranx, growing to a maximum known length of 124 cm and a weight of 32 kg, although is rare at lengths greater than 60 cm. The crevalle jack inhabits both inshore and offshore waters to depths of around 350 m, predominantly over reefs, bays, lagoons and occasionally estuaries. Young fish dispersed north by currents in the eastern Atlantic are known to migrate back to more tropical waters before the onset of winter; however, if the fish fail to migrate, mass mortalities occur as the temperature falls below the species' tolerance.
The flathead grey mullet is an important food fish species in the mullet family Mugilidae. It is found in coastal temperate, tropical and subtropical waters worldwide. Its length is typically 30 to 75 centimetres. It is known with numerous English names, including the flathead mullet, striped mullet, black mullet, bully mullet, common mullet, grey mullet, sea mullet and mullet, among others.
The Pacific staghorn sculpin is a species of marine ray-finned fish belonging to the family Cottidae, the typical sculpins. This species is found in the eastern Pacific Ocean. It is the only species in the monospecific genus Lepidocottus.
The Hawaiian ladyfish, also known as the Hawaiian tenpounder or banana fish, is a species of ray-finned fish in the family Elopidae. It is sometimes referred to as the giant herring, though it is not closely related to the true herrings of the family Clupeidae. Its Hawaiian name is awa 'aua. It is native to the west central Pacific Ocean, and the current classification may in fact consist of several species.
The West African ladyfish is a species of ray-finned fish in the family Elopidae. It is native to the coastal waters of the eastern Atlantic Ocean, from Senegal to Angola. It is also known as the Guinean ladyfish. Some have been known to grow to 20 lb (9.1 kg).
The Senegalese ladyfish is a species of ray-finned fish in the family Elopidae, and it's native to the coastal waters of the eastern Atlantic Ocean from Mauritania to the Democratic Republic of the Congo. It is often confused with the West African ladyfish, Elops lacerta, and can be distinguished only by the number of gill rakers on the lower part of the first gill arch, and the number of scales on the lateral line.
Elops machnata, the tenpounder, is a species of ray-finned fish in the family Elopidae in the order Elopiformes. This species is found in coastal regions of the Indian Ocean.
The Gobiiformes are an order of fish that includes the gobies and their relatives. The order, which was previously considered a suborder of Perciformes, is made up of about 2,211 species that are divided between seven families. Phylogenetic relationships of the Gobiiformes have been elucidated using molecular data. Gobiiforms are primarily small species that live in marine water, but roughly 10% of these species inhabit fresh water. This order is composed chiefly of benthic or burrowing species; like many other benthic fishes, most gobiiforms do not have a gas bladder or any other means of controlling their buoyancy in water, so they must spend most of their time on or near the bottom. Gobiiformes means "goby-like".
The topsmelt silverside, also known as the topsmelt, is a species of Neotropical silverside native to the eastern Pacific Ocean.
The yellowfin whiting, also known as the western sand whiting or fine-scaled whiting, is a species of inshore marine fish in the smelt-whiting family Sillaginidae. The species is endemic to the eastern Indian Ocean, ranging from Dampier, Western Australia to Gulf St Vincent in South Australia, with an apparent division in the populations of the two states. Yellowfin whiting inhabit relatively shallow waters for their entire life, often found on tidal flats and creeks, as well as large estuaries. It is one of the largest members of the smelt-whiting family, growing to 42 cm, and can be distinguished by a number of anatomical and colour related features. Yellowfin whiting are benthic carnivores, preying predominantly on polychaete worms, with minor amounts of copepods, amphipods and bivalves also commonly taken. The species shows a change in diet with age, and also dietary differences with other sillaginids presumably to minimize competition. Reproduction occurs at different times throughout its range, generally focused around summer, with up to 217,000 eggs produced per season. Yellowfin whiting reach sexual maturity at around 20 cm, with each individual spawning more than once. The species forms the basis of major fisheries in both Shark Bay, Western Australia and the two Gulfs of South Australia, with around 260 tonnes of fish taken each year. They are also a popular target for shore based anglers, with a reputation as a very good table fish.
Tarpon are fish of the genus Megalops. They are the only members of the family Megalopidae. Of the two species, one is native to the Atlantic, and the other to the Indo-Pacific Oceans.
Coastal fish, also called inshore fish or neritic fish, inhabit the sea between the shoreline and the edge of the continental shelf. Since the continental shelf is usually less than 200 metres (660 ft) deep, it follows that pelagic coastal fish are generally epipelagic fish, inhabiting the sunlit epipelagic zone. Coastal fish can be contrasted with oceanic fish or offshore fish, which inhabit the deep seas beyond the continental shelves.
E. affinis may refer to:
Azov percarina is a species of ray-finned fish in the family Percidae.
The malacho or Southern ladyfish, is a species of ray-finned fish in the genus Elops, the only genus in the monotypic family Elopidae.