The Malabar snakehead [C. diplogramma], is one of the most enigmatic and least known of all channids

Channa

Channa is a genus of the Channidae family of snakehead fishes. This genus contains about 29 species, but the most well known are probably northern snakehead and the giant snakehead . Channa has a wide natural distribution extending from Iran in the West, to China in the East, and parts of Siberia...

. Sir Francis Day

Francis Day

Francis Day CIE was Inspector-General of Fisheries in India and Burma and an ichthyologist.He was born on 2 March 1829 Maresfield, Sussex, UK third son of William and Ann Day. He became the medical officer in the Madras Presidency, East India Company services in 1852.Francis Day was created a...

 [1] described Ophiocephalus diplogramma in 1865 based on one juvenile specimen (42 mm in length) collected near the mouth of the Cochin River in the port city of Cochin (Southwestern India), and called it Malabar snakehead. The color pattern of this juvenile matched with that of juveniles of another species of snakehead, O. micropeltes originally described by Cuvier and Valenciennes [2] from Java, Indonesia. This possibly led Francis Day to synonymise C. diplogramma with C. micropeltes in 1878 [3]. The close similarity, rarity of adult specimens in museum collections, and the fact that no taxonomist has studied this snakehead since its description, resulted in the acceptance of the synonymy by subsequent taxonomists. In 2011 the C. diplogramma, has been shown to be a valid species 134 years after it was synonymised [4], making it a valid endemic species of peninsular India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

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Biology

Channa diplogramma shows multiple color phases during its life history, which makes local fishers, believe that they are different species. The different specimens are also known by different vernacular names (Pulivaka, Karivaka, Manalvaka, and Charalvaka). All these specimen in different color phases occur sympatrically and utilize the same ecological habitat.

Distribution

Channa diplogramma is endemic to the southern Western Ghats of peninsular India. It is known from the Rivers (including its principal reservoirs) Meenachil, Manimala, Pampa, Achenkovil and Kallada in Kerala

Kerala

or Keralam is an Indian state located on the Malabar coast of south-west India. It was created on 1 November 1956 by the States Reorganisation Act by combining various Malayalam speaking regions....

 state, as well as the Chittar and Tambraparini Rivers (and its reservoirs) in Tamil Nadu

Tamil Nadu

Tamil Nadu is one of the 28 states of India. Its capital and largest city is Chennai. Tamil Nadu lies in the southernmost part of the Indian Peninsula and is bordered by the union territory of Pondicherry, and the states of Kerala, Karnataka, and Andhra Pradesh...

state in India.

Identification

Channa diplogramma differs from all other species in the genus by its high number of lateral line scales (103–105 vs. 36–91). It further differs from all other Channa species, except C. bankanensis, C. lucius, C. micropeltes and C. pleurophthalma by the presence of gular scales, a patch of scales between the anterior tips of the lower jaws, visible in ventral view. Channa diplogramma differs from C. bankanensis, C. lucius, and C. pleurophtalma by having a very different color pattern. C. diplogramma differs from its sister species C. micropeltes by a combination of characters viz., number of caudal fin rays, lateral line scales, scales below lateral line; total vertebrae, pre-anal length and body depth.

Conservation Status

Channa diplogramma is listed as a 'Vulnerable' species in the IUCN Red List of Threatened Species in view of its restricted distribution and threats including fishing, habitat loss and pollution.