Wildlife & Biodiversity

New eel discovered in Odisha after researcher mistakes it for another species

A researcher had initially collected individuals of the new species thinking it is rice-paddy eel

 
By Hrusikesh Mohanty
Published: Tuesday 30 May 2023
New eel discovered in Odisha after researcher mistakes it for another species
Rajesh Kumar Behera and Sruti Rekha Acharya, researchers of the Zoological Survey of India, Gopalpur centre, Odisha, display the new eel species. Photo: Hrusikesh Mohanty Rajesh Kumar Behera and Sruti Rekha Acharya, researchers of the Zoological Survey of India, Gopalpur centre, Odisha, display the new eel species. Photo: Hrusikesh Mohanty

The scientists of the Zoological Survey of India (ZSI) have discovered a new species of eel from Palur canal in Odisha’s Ganjam district. 

The new species has been named Pisodonophis kalinga after the name of ancient Odisha, said Dhriti Banerjee, director of ZSI. She has also proposed kalinga snake eel as the common name of the new species. 

It has a snake-like appearance and varies in length from 560 millimetres to 7 metres. It belongs to the family Ophichthidae and order Anguilliformes. 

The species was found in the Chilika lagoon, Asia’s biggest brackish water lagoon, and the adjoining Palur canal, where water flow is completely tide dependent, said Anil Mohapatra, a senior scientist, Estuarine Biology Regional Centre of ZSI, who led the discovery of the new species in collaboration with the scientists of Berhampur University, Berhampur and Ravenshaw University, Cuttack. The canal connects Chilika with River Rushikulya. 

He said the new species is abundantly found in the region during the monsoon season from September to November. 

Initially, several specimens were collected by Rajesh Kumar Behera, a masters student of Berhampur University, in 2020 to conduct the length and weight relationship by assuming that the species was Pisodonophis boro (rice-paddy eel).

After thorough examination by researchers, the specimens were found to be very distinct from Pisodonophis boro in several aspects like teeth shape, vertebrae range, position of dorsal fin, among others, he said.

After going through the available literature, confusing data emerged, said Mohapatra. This led them to compare these specimens with the correct specimens for Pisodonophis boro, he said.

He said the samples collected from different localities with various morphs were then processed for DNA analysis in its laboratory at ZSI’s EBRC, Gopalpur-on Sea, Odisha in order to clear up any remaining uncertainty regarding morphs.

DNA test results confirmed the two species were related. One was the anticipated Pisodonophis boro, and the other was the novel Pisodonophis kalinga, he said.

After two years of diligent effort, they finally came to the conclusion that Pisodonophis boro has a vertebral count of 16-20, 50-56, 149-156. On other hand the Pisodonophis kalinga has a vertebral count 16-18, 60-62, 170-173. The dorsal side of the body of new species is dark olive-brown, ventrally pale white and both the colors meet at the lateral side.

The dorsal and anal fins have black bases and margins. In certain examples, however, the anal fin is creamy white. These two species are extremely long in length, he said.

Following the discovery of the species, there are now a total of three species of Pisodonophis in the waters of India, Mohapatra added. The eels from the family Ophichthidae have at least 359 valid species within two subfamilies, the Myrophinae (71) and the Orphichthine (288 species), across the world, he said

Right now, the new species has been identified in the Chilika lagoon and Palur canal but it is possible that it is distributed over a wider range. 

The detailed characteristics of this new species Pisodonophis kalinga was published in the international journal Marine Biodiversity in its latest edition of May 29, 2023. 

Subscribe to Daily Newsletter :

Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.