| Sacramento blackfish | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Cypriniformes |
| Family: | Cyprinidae |
| Subfamily: | Leuciscinae |
| Genus: | Orthodon Girard, 1856 |
| Species: | O. microlepidotus |
| Binomial name | |
| Orthodon microlepidotus (Ayres, 1854) | |
| Synonyms | |
Leuciscus microlepidotusAyres, 1854 | |
The Sacramento blackfish (Orthodon microlepidotus) is a species of freshwater fish in central California. A cyprinid, the blackfish is the sole member of its genus.
Blackfish are primarily denizens of the warm and cloudy waters found on the floor of the Central Valley, such as sloughs and oxbow lakes connected to the Sacramento and San Joaquin Rivers. They are also common in Clear Lake, Pajaro River, Salinas River, the small creeks that feed into San Francisco Bay. A population is present in the Russian River, believed to have been introduced. They also thrive in reservoirs, and have been spread to a number of California reservoirs via the California Aqueduct, and into Nevada via the Lahontan Reservoir (1964) where they have further colonized the Humboldt River drainage. [2]
Blackfish are named for their glossy black color. Younger individuals are more silvery, but darken as they age. The scales are unusually small, counting 90-114 along the lateral line. The forehead has a straight-line profile, the eyes are small, and the terminal mouth slants upwards. The dorsal fin starts just behind the pelvic fins, and has 9-11 rays, while the anal fin has 8-9 rays, and the pelvic fins 10 rays. [3] The pharyngeal teeth are distinctly long, straight, and knife-shaped, not seen in similar species in California; the grinding surface of the blackfish, used to process its food, is relatively narrow. [4]
Adults commonly reach a length of 35 cm, but they have been recorded at up to 55 cm in length. [3]
Unlike most North American cyprinids, Sacramento blackfish filter feed on zooplankton, planktonic algae, and floating detritus, including rotifers, copepods, cladocerans, diatoms, and the like. While younger blackfish pick at food items individually, adults primarily use the oral cavity and gills to filter food from water. The blackfish opens and closes its mouth rapidly to pump large volumes of water, the food bits are caught in a patch of mucus on the roof of the mouth, where it is secreted by the palatal organ, and the food bits are swallowed with the mucus. [2] The size of a blackfish influences its eating behavior; larger blackfish, with subsequently larger oral cavities and easier means of filter feeding, are not seen pursuing individual prey like shorter blackfish. [5]
Sacramento blackfish usually live no more than five years. Most blackfish quickly grow during their first and second years, maturing at 2–3 years of age. The blackfishes' breeding season occurs from the spring through early summer, where males will fertilize female eggs in shallow waters. Due to physical stresses from reproduction, many blackfish find spawning difficult and die after two seasons, but some can reproduce up to four times. [2]
Orthodon microlepidotus, the common name for the Sacramento blackfish, refers to the fish's straight teeth (Orthodon) and its distinctly small scales (microlepidotus). The Orthodon genus is monotypical, making the blackfish the sole member of the genus and a generally unvaried species. [2] Despite its unique characteristics, the blackfish has been recorded reproducing hybrids with the Hitch and Tui Chubs, members of the blackfish's subfamily Leuciscinae also found in California.
The IUCN labels the Sacramento blackfish as being of "least concern"—though less abundant than previously in California's Central Valley, the blackfish is at low risk of endangerment. Blackfish are known for their adaptations to environmental extremes, especially adapting to fluctuating water temperatures. A study by Joseph J. Cech Jr., a professor at the University of California, Davis, found that the blackfish was able to thrive in hypoxic environments. [6]
Sacramento blackfish are of some commercial significance, and are sold live at many Asian fish markets in California.They are also seen as a potential aquaculture species. [2]
Blackfish is a common name for the following species of fish, dolphins, and whales:
The Sacramento perch is an endangered sunfish native to the Sacramento–San Joaquin River Delta, Pajaro, and Salinas River areas in California, but widely introduced throughout the western United States.
The chiselmouth is an unusual cyprinid fish of western North America. It is named for the sharp hard plate on its lower jaw, which is used to scrape rocks for algae. It is the sole member of the monotypic genus Acrocheilus and is a close relative of the Gila western chubs.
The California roach is a cyprinid fish native to western North America and abundant in the intermittent streams throughout central California. Once considered the sole member of its genus, it has recently been split into a number of closely related species and subspecies.
The mountain sucker is a sucker found throughout western North America, on both sides of the Rocky Mountains, including the upper Missouri River, Columbia River, Sacramento River, and Colorado River. It is not limited to higher altitudes but is known from locations as high as 2,800 m (9,200 ft). It is a slender, streamlined fish typically under 20 cm (8 in) in length. It is generally olive green or brown above, with pale underparts, and breeding males have a lateral red-orange band and fins suffused with the same color. It is mainly herbivorous, feeding on algae and diatoms. Breeding takes place in late spring and early summer in gravelly riffles in small streams.
The hitch is a cyprinid fish endemic to central California, and was once very common. The common name may derive from a Pomoan word for this species. It is the only species in the monospecific genus Lavinia.
The splittail, also called Sacramento splittail, is a cyprinid fish native to the low-elevation waters of the Central Valley in California. It was first described by William O. Ayres in 1854. It is the sole living member of its genus, the Clear Lake splittail P. ciscoides having become extinct in the 1970s.
The European perch, also known as the common perch, redfin perch, big-scaled redfin, English perch, Euro perch, Eurasian perch, Eurasian river perch, Hatch, poor man’s rockfish or in Anglophone parts of Europe, simply the perch, is a predatory species of the freshwater perch native to Europe and northern Asia. The species is a popular quarry for anglers, and has been widely introduced beyond its native area, into Australia, New Zealand and South Africa. They have caused substantial damage to native fish populations in Australia and have been proclaimed a noxious species in New South Wales.
The scoophead is a little-known species of hammerhead shark, part of the family Sphyrnidae. It inhabits the tropical waters of the western Atlantic Ocean, from Panama to southern Brazil, and in the eastern Pacific Ocean from the Gulf of California to Ecuador, and probably northern Peru, as well. It is found in shallow, inshore habitats.
The lollipop catshark is a little-known species of deep sea catshark, belonging to the family Scyliorhinidae, and the only described member of its genus. A diminutive, bottom-dwelling shark of the outer continental shelf and upper continental slope, this species can be readily identified by its tadpole-like shape with a greatly expanded, rounded head and narrow body. The large head houses expanded gills, which are thought to be an adaptation for hypoxic conditions. This shark preys on crustaceans and fishes. Reproduction is aplacental viviparous, with females retaining egg cases internally two at a time until they hatch. There is no fishery interest in this species.
The bentfin devil ray, also known as the lesser devil ray, smoothtail devil ray, smoothtail mobula or Thurston's devil ray, is a species of ray in the family Mobulidae. It is found worldwide in tropical, subtropical and warm temperate oceans, with records from Australia, Brazil, Chile, Costa Rica, Ecuador, Egypt, El Salvador, Eritrea, Guatemala, Honduras, India, Indonesia, Ivory Coast, Japan, Malaysia, Maldives, Mexico, Myanmar, Nicaragua, Oman, Pakistan, Peru, the Philippines, Saudi Arabia, Senegal, South Africa, Sri Lanka, Thailand, United Arab Emirates, United States (California), Uruguay, Vanuatu and throughout the central and western Pacific. It likely occurs in many other locations in tropical, subtropical and warm temperate oceans. It is found both offshore and near the coast.
Naso lituratus is a species of fish in the family Acanthuridae, the tangs and unicornfishes. Its common names include barcheek unicornfish, naso tang, and orange-spine unicornfish.
The six-line wrasse is a species of marine ray-finned fish from the family Labridae which has a wide Indo-Pacific distribution. This species is associated with coral reefs and can be found in the aquarium trade.
The mangar is a large species of ray-finned fish in the genus Luciobarbus, native to the Tigris–Euphrates river system in Iran, Iraq, Syria and Turkey.
Silverjaw minnows are part of the family Cyprinidae, which includes carps and minnows. With over 300 known species, there are more species of minnows native to North America's fresh waters than any other fish. Minnows can be hard to distinguish because many look alike. All minnows have one dorsal fin, ventral fins near the anus, a lateral line system, and smooth, round cycloid scales. Their jaws lack teeth, but they have one to three rows of pharyngeal teeth to grind food. Defining physical characteristics such as the number and type of fin rays, type of scales, and pattern of pharyngeal teeth are used to distinguish minnows.
Gyrinocheilus aymonieri is a freshwater fish native to large parts of Southeast Asia. It is of interest as a local food source and for the aquarium trade. Its common names include honey sucker, sucking loach and Chinese algae eater.
The Allegheny pearl dace is a species of cyprinid fish. It is demersal, freshwater fish, with a dark green back and silvery body. This species is omnivorous, consuming algae, as well as arthropods. M. margarita's range spans southern Canada and the northern United States. While not considered endangered at the federal level in the United States, several states either consider this species endangered or threatened; it faces threats of habitat destruction and invasive species.
Mylopharadon conocephalus, known as the hardhead, is a freshwater ray-finned fish from the family Cyprinidae, the carps and minnows, which is endemic to California. It is the sole member of the monotypic genus Mylopharadon.
Securicula gora is a species of cyprinid fish found in Bangladesh, India, Pakistan and possibly in Nepal. It is the only species in its genus.
The humpback mahseer is a species of freshwater ray-finned fish from the Indian endemic genus Hypselobarbus in the carp and minnow family Cyprinidae.
