River shark

Glyphis is a genus in the family Carcharhinidae, commonly known as the river sharks. This genus was thought to contain five different species, but recent studies on molecular data revealed that the species Glyphis gangeticus has an irregular distribution in the Indo-West Pacific region.[2] This genus contains only four extant species. Further species could easily remain undiscovered, due to the secretive habits of Glyphis sharks.[3] Their precise geographic range is uncertain, but the known species are documented in parts of South Asia, Southeast Asia, New Guinea, and Australia. Of the four currently described species, the Ganges shark is restricted to freshwater, while the northern river shark and the speartooth shark are found in coastal marine waters, as well. While the bull shark (Carcharhinus leucas) is sometimes called both the river shark and the Ganges shark, it should not be confused with the river sharks of the genus Glyphis. The River sharks of the genus Glyphis, remain very poorly known to science. They are facing a critically endangered status since river sharks are so poorly studied, and people know very little about their population and life history. One of the primary threats to River Sharks is habitat degradation which includes: human development, pollution, and fishing. The river shark is known to be one of the most rare sharks in the world. They have been found in nine different tidal areas, which consists of muddy waters with a low salinity. Their placement in connection to coastal marine waters indicate that they are usually born around October.

River shark Temporal range: Miocene – Recent PreЄ Є O S D C P T J K Pg N ↓ [1]
Speartooth shark, Glyphis glyphis
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Chondrichthyes
Order:	Carcharhiniformes
Family:	Carcharhinidae
Genus:	Glyphis Agassiz, 1843
Type species
Carcharias (Prionodon) glyphis Müller & Henle, 1839