A new species of fish has been discovered in the Western Ghats in India. Named Pethia striata, the fish was uncovered in a stretch of the Tunga River that falls within the Kudremukh National Park, in the central part of the Western Ghats, Karnataka.
V M Atkore, an ecologist and a PhD student at the Bangalore-based Suri Sehgal Centre for Biodiversity and Conservation, was studying the effects of habitat disturbance on fish biodiversity in the Kudremukh National Park when he stumbled upon this discovery. “It was May 9, 2011”, he recollects, “when I saw this fish. I am conversant with the aquatic life of the region as I have studied it extensively, but this was a fresh specimen.” He promptly sends photographs to K Rema Devi, incharge, Southern Regional Centre of Zoological Survey of India, who confirmed his hunch of this being a hitherto undiscovered species.
Atkore and his team concluded that the 3-4 cm long species were distinct in several ways, but the most striking characteristics were the pattern of scales, which form oblique bars and the black blotch just before the tail. Very distinct rings are also visible in both the sexes.
The American Society of Ichthyologists and Herpetologists, in the journal Copia, documented that the new species is distinguished from its congeners by the combination of the following characters: absence of barbels; stiff and serrated last unbranched dorsal-fin ray; complete lateral line with 20–21 poured scales and a relatively small humeral spot one scale below the fourth lateral-line scale; a large black blotch covering lateral-line scales 17–19. In addition, the outer edges of body scales are dark, producing a striped pattern along the sides of the body.
In an interview with G‘nY correspondent, Atkore revealed that the Pethia striata is found only in the two streams of Mudba and Turad, a region populated by wet evergreen and semi-evergreen forests. “Though I have studied other river systems in Karnataka and Goa like Bhadra, Malaprabha and Mhadei, I haven’t come across this species at all. It is typically restricted to these headwaters with medium to dense forest canopy”.
The team’s study also reveals that these little fish generally gather in small groups of 3-4 individuals in shallow pools with gently flowing water. Experts stated that the new species would be an addition to Cyprinidae, the largest family of fish that encompasses other common fishes like the gold fish, zebra fish, and the common carp.
Numerous species with near similar description, encountered elsewhere in India, Bangladesh, Myanmar, and Sri Lanka, have been referred to as Pethiaticto.
The Western Ghats, is one of the three biodiversity hotspots of India and one of the eight ‘hottest hotspots’ in the world. And, like most others, is under the constant threat of habitat destruction. Atkore professed that increasing human presence puts pressures on the natural resources and freshwater diversity is very sensitive to changes like water diversion and dams. He also said that discovery of new species is possible in the less disturbed streams, and such discoveries are important to increase conservation efforts for this area.
Some of the other recently discovered new species in the Western Ghats include a little jumping spider in the Southern Ghats, a new frog species in Central Ghats.