Why In News?

Researchers from Kohima Science College discovered a new species of rock-clinging catfish, Pseudecheneis likimroensis, in the Likimro River.

What is Pseudecheneis likimroensis?

Aspect

Details

Discovery

New species discovered from the Likimro River, Kiphire district, Nagaland by researchers from Kohima Science College and the Zoological Survey of India (ZSI). 

Habitat

Rheophilic hillstream catfish inhabiting fast-flowing, rocky mountain streams with highly oxygenated water.

Meaning of Rheophilic

Derived from Greek "Rheos" (flow/current) and "Philos" (loving); refers to organisms adapted to live in swift-flowing waters. 

Major Adaptations

Dorso-ventrally flattened body, thoracic adhesive organ (suction plate), strong pectoral fins and streamlined profile enable attachment to rocks in turbulent streams.

Distinctive Features

Adhesive organ with parallel ridges and grooves, deep body, unique bony spur on first dorsal-fin pterygiophore, distinct fin-ray counts and vertebral characteristics. 

Diet

Carnivorous; feeds mainly on aquatic insects, insect larvae and small benthic organisms attached to rocks.

Size

Holotype: 11.53 cm; Largest recorded specimen: 13.19 cm. 

Diagnostic Characters

Distinguished from congeners by body depth, pectoral fin-ray count, vertebral structure, exposed lower tooth band and dorsal bony spur. 

Local Names

Known as "Nupedro" by the Chirr Naga community; also called "Jetfighter" or "Aeroplane Fish" due to wing-like pectoral fins and camouflage appearance.  

Ecological Importance

Indicator of pristine, highly oxygenated hill streams; regulates aquatic insect larvae and contributes to stream ecosystem stability.

About Likimro River

  • Location: Eastern Kiphire District, Nagaland, along the India–Myanmar border.

  • Origin: Originates near Mount Saramati, the highest peak of Nagaland.  

  • River Type: Fast-flowing mountain river with deep valleys, rocky substrates and boulder-strewn channels.  

  • Drainage System: Tributary of the Tizu River, part of the Chindwin–Irrawaddy Basin, unlike most Northeast Indian rivers that drain into the Brahmaputra.  

Source: mongabay

PRACTICE QUESTION

Q. With reference to Indian freshwater ecosystems, how is a "rheophilic" organism best described? 

A) An organism adapted exclusively to stagnant, highly alkaline lentic wetlands. 

B) A species that undergoes migration from saltwater oceans to freshwater rivers to spawn. 

C) An organism that thrives in fast-flowing, highly oxygenated mountain streams.

D) A highly invasive species that outcompetes native coldwater fishes for food.

Answer: C

Explanation: Rheophilic organisms (from Greek "rheos" meaning current, and "philos" meaning loving) are species biologically adapted to living and thriving in fast-moving, swift, and highly oxygenated mountain stream waters