Channa


Channa is a genus of predatory fish in the family Channidae, commonly known as snakehead, native to freshwater habitats in Asia. This genus contains about 50 scientifically described species. The genus has a wide natural distribution extending from Iraq in the west, to Indonesia and China in the east, and parts of Siberia in the Far East. A particularly high richness of species exists in Myanmar and northeastern India, and many Channa species live nowhere else. In contrast, a few widespread species have been introduced to several regions outside their natural range where they often become invasive. The large and medium-sized Channa species are among the most common staple food fish in several Asian countries and they are extensively cultured. Apart from their importance as a food fish, snakeheads are consumed in some regions as a traditional medicine for wound healing and reducing post-operative pain and discomfort, and collected for the international aquarium pet trade.
All snakeheads are highly predatory and the diets of the various species of Channa include fish, amphibians, snakes, rodents, birds and invertebrates. They have a labyrinth organ, which allows them to breathe air for short periods, and they use this adaptation to travel across land in the event that their habitat becomes inhospitable. They are mostly solitary or live in monogamous pairs that are highly aggressive towards outsiders of their own species, but C. pleurophthalma often occurs in small groups. Larger species are mostly nestbrooding, and the dwarfs mostly paternal mouthbrooding, but there are exceptions: the large C. barca is a paternal mouthbrooder and the dwarf C. bleheri is a free-spawner.
In Assamese it is called goroi. In Malayalam it is called varal or braal. In Bhojpuri it is called "garai". In the Magahi language it is called “garai”. Since the fish can survive in marshy land, which is not a habitat for normal fishes, there are Magahi phrases like ‘gadal garai’. This is used to describe a person who looks simple but is shrewd.

Taxonomy

The taxonomy of the genus Channa is incomplete and a comprehensive revision of the family has not been performed. A phylogenetic study in 2010 has indicated the likelihood of the existence of undescribed species of channids in Southeast Asia, and a more comprehensive phylogenetic study in 2017 indicated that there are several undescribed species in Asia. In 2011, the Malabar snakehead Channa diplogramma from peninsular India was shown to be a distinct species, 146 years after its initial description and 134 years after it was synonymised with C. micropeltes, establishing it is an endemic species of peninsular India. The study also suggested that the species shared a most recent common ancestor with C. micropeltes, around 9.52 to 21.76 MYA.

Species

There are currently 50 recognized species in this genus: