Confirming the presence of an endangered fish fresh water dwarf puffer or Carinotetraodan imitator in the Western Ghats region, a group of researchers has found a group of the species in the Kumaradhara River on the Kerala-Karnataka border in India.

It is the first record of the fish from the wild, according to international journal ‘Ichthyological Exploration of Freshwaters’ that published the findings of the group, comprising scientists of conservation research group (CRG) of St Albert’s College, Kochi. They collected five male and two female fish from the river.

The fish, included in the list of threatened species published by International Union for Conservation of Nature (IUCN), was being exported to many countries from the state as aquarium fish for the past many years but scientists had so far failed in describing its natural distribution.

The genus Carinotetraodon currently comprises six valid species of dwarf puffer fishes restricted to freshwaters in Asia. The C. travancoricus and C. imitator are the two varieties found in peninsular India.

The members of the research group include Ralf Britz of Department of Life Sciences, The Natural History Museum, London, Anwar Ali, Rajeev Raghavan and Siby Philip of Conservation Research Group and Krishna Kumar of Community Environment Resource Centre, Alappuzha.

Anwar Ali said though the natural distribution of a fish or a bird or an animal is most important while describing the species by scientists, the natural distribution of C. imitator had remained elusive for scientists across the world so far. “We were able to collect a number of dwarf puffer fishes from the river and a closer study showed that they are clearly C. imitator and it was the first record of this species from a river,” he said.

Carinotetraodon imitator is easily distinguished by details of its colour pattern from its only Indian congener, C. travancoricus. Male C. imitator is bright yellow and lacks the large black body blotches of C. travancoricus. Female C. imitator also has much smaller and fainter body blotches but has a large number of tiny spots in addition, according to the group.

As per the data published so far, Tetraodon travancoria was the only known freshwater puffer fish from the Western Ghats and even the IUCN was unclear about the natural distribution of the C.imitator fish while describing its Red List, researchers said.

“Though we still do not have the entire and precise distributional range of C. imitator, we expect that C. imitator is more widely distributed in the Western Ghats and are confident that it can be identified from other streams in the region,” Ali said.

2012 Bennett, Coleman & Co. Ltd.