The clown featherback, clown knifefish, or spotted
knifefish, Chitala ornata, is a nocturnal tropical fish with a long, knife-like
body. This knifefish is native to freshwater habitats in Cambodia, Laos,
Thailand and Vietnam, but it
has also been introduced to regions outside its native range.
It is often seen in aquaculture and the aquarium trade where
frequently confused with Chitala chitala; the latter species is very rare in
the aquarium trade. Despite its popularity, the clown featherback reaches 1 m
(3.3 ft) in length, outgrowing all but the largest aquaria.
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| Clown Knifefish Fish |
Ocellate River Stingray
Fish
The ocellate river stingray (Potamotrygon motoro), also
known as the peacock-eye stingray, is a potamodromous freshwater ray native to
the basins of the Uruguay,
Paraná, Orinoco, and Amazon
Rivers.
It is known to grow up to 1 m (3 ft.) TL and 15 kg (33 lb.).
Its disk is roughly circular in shape, and its eyes are raised from the dorsal
surface. The dorsal coloration is beige or brown, with numerous light orange
spots with dark rings. The arrangements of these spots can vary from fish to
fish.
Ocellate river stingrays are sometimes kept in captivity,
with requirements similar to other members of Potamotrygon. It is one of the
most common species of Potamotrygon in the aquarium.
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| Ocellate River Stingray Fish |
Black Devil Stingray
Fish
The Xingu River ray, white-blotched river stingray, or
polka-dot stingray, Potamotrygon leopoldi, is a species of fish in the
Potamotrygonidae family endemic to Brazil. Its natural habitat is
rivers. It is threatened by habitat loss.
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| Black Devil Stingray Fish |
Sterlet Fish
The sterlet (Acipenser ruthenus) is a relatively small
species of sturgeon from Eurasia native to large rivers that flow into the
Black Sea, Azov Sea, and Caspian Sea, as well as rivers in Siberia as far east as
Yenisei. Populations migrating between fresh and salt water (anadromous) have
been extirpated.
Due to overfishing (for its flesh, caviar, and isinglass),
pollution, and dams, the sterlet has declined throughout its native range and
is considered vulnerable by the IUCN. Restocking projects are ongoing, and it
has been introduced to some regions outside its native range, but the latter
have generally not become self-sustaining. Today, the majority of the
international trade involves sterlets from aquaculture.
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| Sterlet Fish |
Shovelnose Sturgeon
Fish
The shovelnose sturgeon, Scaphirhynchus platorynchus, is the
smallest species of freshwater sturgeon native to the United States of America. It is
often called "hackleback", "sand sturgeon", or
"switchtail." Switchtail refers to the long filament found on the
upper lobe of the caudal fin (often broken off as adults). Shovelnose sturgeon
are the most abundant sturgeon, found in the Missouri River and Mississippi
River systems, and the only commercially fished sturgeon in the United States of America
(Pflieger 1997).
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| Shovelnose Sturgeon Fish |
Freshwater needlefish
Xenentodon cancila (freshwater garfish) is a species of
needlefish found in freshwater and brackish habitats in South and Southeast Asia.
As a reasonably popular aquarium fish Xenentodon cancila,
has been traded under a variety of common names, including needlefish, silver
needlefish, Asian freshwater needlefish, needlenose halfbeak, freshwater gar,
needlenose gar and numerous others. While belonging to the same family as the
marine needlefish known in Europe as gar or garpike, Belone belone, these fish
are much more distantly related to other fishes sometimes called gars (such as
the North American gars and South American pike characins). In Assam
it is locally known as Kokila.
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| Freshwater needlefish |
Pickerel Fish
The American pickerels are two subspecies of Esox
americanus, a species of freshwater fish in the pike family (family Esocidae)
of order Esociformes: the redfin pickerel, E. americanus americanus Gmelin,
1789, and the grass pickerel, E. americanus vermiculatus Lesueur, 1846.
Both subspecies are native to North
America. They are not to be confused with their aggressive
counterpart the Northern pike. The redfin pickerel's range extends from the
Saint Lawrence drainage in Quebec down to the Gulf Coast, from Mississippi to
Florida, while the grass pickerel's range is further west, extending from the
Great Lakes Basin, from Ontario to Michigan, down to the western Gulf Coast,
from eastern Texas to Mississippi.
The two subspecies are very similar, but the grass pickerel
lacks the redfin's distinctive orange to red fin coloration, its fins having
dark leading edges and amber to dusky coloration. In addition, the light areas
between the dark bands are generally wider on the grass pickerel and narrower
on the redfin pickerel. These pickerels grow to a maximum overall length of 40
cm (16 in) and a maximum weight of 2.25 pounds
The redfin and grass pickerels occur primarily in sluggish,
vegetated waters of pools, lakes, and swamps, and are carnivorous, feeding on
smaller fish. Larger fishes, such as the striped bass (Morone saxatilis),
bowfin (Amia calva), and gray weakfish (Cynoscion regalis), in turn, prey on
the pickerels when they venture into larger rivers or estuaries.
These fishes reproduce by scattering spherical, sticky eggs
in shallow, heavily vegetated waters. The eggs hatch in 11–15 days; the adults
guard neither the eggs nor the young.
The E. americanus subspecies are not as highly prized as a
game fish as their larger cousins, the northern pike and muskellunge, but they
are caught by anglers. McClane's Standard Fishing Encyclopedia describes
ultralight tackle as a sporty if overlooked method to catch these small but
voracious pikes.
Lesueur originally classified the grass pickerel as E. vermiculatus,
but it is now considered a subspecies of E. americanus.
E. americanus americanus is sometimes called the brook
pickerel. There is no widely accepted English common collective name for the
two E. americanus subspecies; "American pickerel" is a translation of
the systematic name and the French brochet d'Amérique.
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| Pickerel Fish |
Brook stickleback
The brook stickleback (Culaea inconstans) is a small
freshwater fish that is distributed across the US
and Canada.
It grows to a length of about 2 inches. It occupies the northern part of the
eastern United States, as
well as the southern half of Canada.
Small populations are scattered throughout the Mississippi-Great
Lakes basin extending to Colorado, New Mexico, Kentucky, Tennessee,
etc., though some of these areas are not native to the species. This small fish
inhabits clear, cool streams and lakes. They eat small invertebrates, algae,
insect larvae, and occasionally their own eggs. They are also preyed upon by
smallmouth bass and northern pike. Feeding time is usually dawn and sunset. The
brook stickleback does have active competition mostly from minnows, but feeding
times are different, along with diet. Spawning occurs in midsummer. Males
secure a territory, build a nest, and mate with females. Males provide
protection for the eggs, ward off predators, and usually die later in the
season. This is considered an annual species. The nests are built out of
aquatic grasses. Though the brook stickleback is not considered a threatened
species, deforesting and changing waters are altering ecosystems of the
species. Harvesting of trees around riparian environments is having a large
effect of the stream ecosystem where the brook stickleback resides.
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| Brook stickleback |
Medaka Fish
The Japanese rice fish (Oryzias latipes), also known as the
medaka and Japanese killifish, is a member of genus Oryzias (ricefish), the
only genus in the subfamily Oryziinae. This small (up to 3.2 cm or 1.3 in)
native of east and mainland southeast Asia is a common denizen of rice paddies,
marshes, ponds, slow-moving streams and tide pools. It is euryhaline, occurring
in both brackish and freshwater. It became popular as an aquarium fish because
of its hardiness and pleasant coloration: its coloration varies from brown or
yellow-gold in the wild to white, creamy yellow, or orange in aquarium-bred
individuals. The medaka has been a popular pet since the 17th century in Japan. The
female carries her eggs attached between her anal fins.
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| Medaka Fish |
European Perch Fish
Perca fluviatilis, commonly known as the European perch,
perch, redfin perch or English perch, is a predatory species of perch found in
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.
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| European Perch Fish |
Lungfish
Lungfish (also known as salamanderfish) are freshwater fish
belonging to the subclass Dipnoi. Lungfish are best known for retaining
characteristics primitive within the Osteichthyes, including the ability to
breathe air, and structures primitive within Sarcopterygii, including the
presence of lobed fins with a well-developed internal skeleton.
Today, lungfish live only in Africa, South America and Australia.
While vicariance would suggest this represents an ancient distribution limited
to the Mesozoic supercontinent Gondwana, the fossil record suggests advanced
lungfish had a widespread freshwater distribution and the current distribution
of modern lungfish species reflects extinction of many lineages subsequent to
the breakup of Pangaea, Gondwana and Laurasia.
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| Lungfish |