Freshwater Sharks: Here Are The Known Species
Do you know freshwater sharks? When we think of a shark, we imagine it swimming near a beach or in the depths of the oceans.
There are, however, also freshwater sharks, which we will discuss in this article.
What are freshwater sharks?
This type of fish, called Glyphis , is really strange and there is little information about it.
This is because the species that are part of it often remain hidden in their habitat. Unlike their marine relatives, these large fish live in streams, lakes and rivers.
There are currently 6 known types of freshwater sharks, one of them already extinct and the others at risk of extinction:
1. Spear-toothed shark
It is a little known type of shark that lives in Australia, New Guinea and Malaysia. It prefers the murky waters of rivers, tropical mangroves and estuaries far from the coasts.
The largest specimen found to date measures 2.5 meters. The body of this species is streamlined, robust and with a broad, short head that includes a flattened snout and a large nose that ends in a triangle.
Its jaws are wide and the teeth have tight edges that allow it to feed mainly on bony fish or crustaceans. It is not a very active shark but, in case of need, it swims at great speeds.
2. Shark of the Irrawaddy River
This cartilaginous fish from the Carcharhinidae family was analyzed following the capture of a specimen in the Irrawaddy River in Burma. In fact, it prefers brackish waters with sediments and mangroves. The body is gray and its skin very thick. It has a short and rounded snout, small eyes and nasal cavities and long dorsal fin.
There are various reasons why this shark is in serious danger of extinction : intensive fishing with nets and electronic devices, water pollution, the destruction of mangroves and the very restricted distribution area.
3. New Guinea river shark
Another freshwater shark that, in this case, lives in the rivers of Papua New Guinea and in the north of Australia, mainly in areas with poor visibility, large tides and white bottoms.
It is very similar to another species of freshwater shark belonging to the genus Glyphis : robust body, flattened head, rounded snout, small eyes and large mouth with 34 rows of teeth in the upper jaw and 35 in the lower one, all pointed.
These fish are not often seen and it is estimated that there are only 250 specimens in the wild. Often being caught illegally by commercial or sport fishermen and living in a degraded habitat, much effort has been made to prevent extinction, such as creating a protected area in Kakadu in northern Australia.
4. Shark of the Ganges
This species is very rare and can only be observed in one of the most important rivers in the world, just like its close relative, the bull shark, with which it is usually confused.
It can also be observed in the middle and lower courses of other Indian rivers: Hooghly, Brahmaputra, Bihar and Orissa.
The Ganges shark has a dark gray body, spotless, compact and with a rounded snout.
It is a vital species in the river ecosystem and is said to be quite dangerous to humans, although this has not been confirmed by scientists.
5. Borneo river shark
The last freshwater shark we have information about is small (the females measure about 80 centimeters and are slightly larger than the males) and it is thought that to date only 30 specimens remain in their natural habitat (rivers and lakes of Borneo), therefore it is in serious risk of extinction.
The river shark of Borneo feeds on crabs and fish that it catches thanks to its sturdy square snout and its teeth as sharp as arrows. Its body is silver and reproduces viviparously.
