SHILLONG: The caves of Meghalaya hide numerous marvels and the latest find by a team of cavers may add another jewel to the state’s crown.
The team comprising international cave explorers encountered a new species of cave fish in Jaintia Hills in February and it appears to be the largest known cave fish in the world.
A specimen is currently under examination by Meghalayan biologists who are working to characterise and name the new species.
The new species, a type of carp (Cyprinidae), exceeds 40 cm in length and is also considerably bulkier and heavily built than the cave eels. The fish were in large numbers inside the cave and were seen in almost all the larger pools of water.
The experts in the team — which works in close association with Meghalaya Adventurers Association’ led by Brian Kharpran Daly — believe the fish population is in the hundreds.
Some species within this group are long-lived and it is possible that the larger individuals of the new species may be many decades old.
The fish showed no fear of humans and came to investigate when boots or hands were placed within the pools.
About 250 species of subterranean fish are known worldwide. The vast majority of these species are relatively small, being typically less than 15 cm in length. There are a few larger species, including some long, thin-bodied ‘eels’ that reach 35 cm in length.
Subterranean fish typically lack pigmentation and are white or pinkish in colour. Their eyes are typically reduced in size or entirely absent. These features are obvious in the new species. The smaller juveniles had small sunken eyes but eyes were almost entirely absent in the larger adult fish.
Like many cave animals, the ability of the fish to move to new areas tends to be constrained by the layout of the caves in which they live.
In some cases, the entire world population of a species may be restricted to a single cave system.
If that is the case with the new species of fish, it would make the species extremely vulnerable even to localised impacts that might be associated with changing land use, pollution or harvesting.
Though the entrance of the cave, where the species was found, is well known to locals, access to the inner parts of the cave requires specialist vertical caving techniques. Below the vertical entrance, there is an extensive series of large horizontal passages with numerous pools and streamways.
The cave floods during the rainy months as patches of forest vegetation deposited by flood waters were seen deep within the cave system.
The discovery of the new species comes after the cavers found the country’s deepest shaft cave, Krem Um Ladaw. Once the biologists complete their examination of the specimen, Meghalaya can happily say, “Thank you for all the fish.”