31-May-2020: Rare scorpionfish found in Gulf of Mannar

Researchers at the Central Marine Fisheries Research Institute (CMFRI) have found a rare fish from Sethukarai coast in the Gulf of Mannar. Camouflaged within the seagrass meadows, the band-tail scorpionfish ( Scorpaenospsis neglecta ), well-known for its stinging venomous spines and ability to change colour, was found during an exploratory survey of the seagrass ecosystem.

This was the first time that the particular species was found alive in Indian waters. The fish has the ability to change colour and blend with its surrounding environment to escape from predators and while preying.

The fish is called ‘scorpionfish’ because its spines contain neurotoxic venom. When the spines pierce an individual, the venom gets injected immediately and it can be extremely painful. Eating the fish would lead to death.

The specimen has been deposited in the National Marine Biodiversity Museum of the CMFRI. The research work was published in the latest issue of the journal Current Science.

23-Feb-2020: World’s largest cave fish discovered in India

Regular flooding leaving ample trails of vegetation and scores of unknown organisms found inside the caves located in the dense forests of Jaintia Hills in Meghalaya could have been the main feed for the recently discovered world’s largest cave fish.

Discovery of the fish, measuring 40 cm, has left more questions for scientists to answer — on its evolution, presence in the caves of Meghalaya and its large size. This fish, Tor putitora, is commonly found in the rivers that flow along the foothills of the Himalayas. But we still do not know how it landed up in caves in Meghalaya.

A team of international scientists stumbled upon the fish in February last year, when they were carrying out some cave studies in the region as part of Caving In the Abode of Clouds Project, which was launched in 1992. Under the project, scientists have been studying and mapping caves in Meghalaya.

Tor putitora are commonly found in river waters across India, Pakistan, Afghanistan, Bhutan, Nepal and Myanmar. Some varieties of this fish were previously discovered from Garo Hills in Meghalaya. As the fish is known to enter into rapid-flowing streams and pools, which are present adjacent to Jaintia Hills, experts suggest this to be one of the sources for their reaching and breeding inside the Meghalayan caves.

It is not the first time that cave fish species has been discovered in Meghalaya. However, they have mostly been smaller in size. There are about 250 known varieties of subterranean fish with a majority of them ranging between 20 mm and 130 mm in size. Very few subterranean fish species discovered so far have been found to grow between 130mm and 230mm. Normally, cave fish do not grow into large fish due to sheer lack of sunlight, thereby making the environment limited in nutrients and scare in food resources.

Yet another striking feature that the biologists noted was the development of eyes among the fish. The smaller fish were slender while the larger ones were found to be bulky in nature. Significantly, in all the fish inside the caves, eyes were found to be regressed. Black-coloured regression marks were more prominently visible among the smaller fish. The eyes in case of the largest fish were severely regressed and was invisible unless closely examined.

This must be a development phase, and it is common for cave fish to lose eyes as they grow. Also, since they live in dark environments, the role of eyes is limited. But the researchers noticed that despite having no eyes, the fish were sensitive to light. This was concluded when the fish disappeared when the team members flashed cave torch light onto them. The smaller fish were capable of showing rapid response to light and were difficult to approach, in comparison to the larger ones.

23-Jan-2020: ZSI documents another new snake eel species in Odisha

A new snake eel species residing in the Bay of Bengal has been discovered and documented this month (January) by the Estuarine Biology Regional Centre (EBRC) of the Zoological Survey of India (ZSI) at Gopalpur-on-sea in Odisha.

This new marine species has been named Ophichthus kailashchandrai to honour the vast contributions of Dr. Kailash Chandra, Director of ZSI, to Indian animal taxonomy. Ophichthus kailashchandrai is the eighth species of the Ophichthus genus found on the Indian coast. It is the fifth new species discovered by the Gopalpur ZSI in the last two years.

In 2019, two new species of marine eel, Gymnothorax andamanensesis and Gymnothorax smithi have been discovered by this ZSI centre.

Three specimens of the new species were collected from the Shankarpur fishing harbour in the northern region of the Bay of Bengal on the West Bengal coast in 2015. Detailed study for over four years led to the discovery that they belonged to a newly discovered species living in the Bay of Bengal.

The eel family ‘Ophichthidae’ comprises two sub-families — Myrophinae (69 species) and Ophichthinae (276 species). The sub-family Ophichthinae is identified by its hard tail and other osteological (bone) features, and it has 17 genera and 24 species. Out of them, seven species from the Ophichthus genus were earlier identified in Indian waters. The recent discovery is the eighth species of this genus.

The Ophichthus kailashchandrai lives at a depth of around 50 metres in the sea. According to the studied specimens, individuals of this species are around 420 mm to 462 mm in length. They are light brown in colour, with white fins. They have a well-developed pectoral fin and also have a dorsal fin. Their posterior nostril is a hole covered by a flap on the upper lip opening towards the mouth. There are 180-182 total vertebrae in this new species. Their teeth are moderately elongated, conical and sharp.

Ophichthus kailashchandrai feeds on small fish and crabs. The outer surface of their bodies is slimy but they are not poisonous. The discovery of the new species suggests that the marine biodiversity of the long Indian coastline is still considerably unexplored. More explorations of this biodiversity will help in its conservation and proper utilisation.

17-Aug-2019: New species of freshwater fish found

Scientists of the Zoological Survey of India have discovered two new species of freshwater fish from the north-eastern and northern parts of the country.

While Glyptothorax gopii , a new species of catfish was found in Mizoram’s Kaladan river, Garra simbalbaraensis was found in Himachal Pradesh’s Simbalbara river. Both fish, measuring less than seven centimetres, are hill stream fauna and are equipped with special morphological features to suit rapid water flow.

Both these species were discovered from remote areas, for instance, Glyptothorax gopii was discovered from Champai district in Mizoram near the India-Myanmar border. Garra simbalbaraensis has been found from Sirmour district of Himachal Pradesh.

In Glyptothorax gopii, the elliptical thoracic adhesive apparatus and plicae (folds of tissue) present on the ventral surfaces of the pectoral-fin spine help the fish cling to rocks.

Garra simbalbaraensis has a prominent unilobed and rounded proboscis with tubercles that help the fish in manoeuvrability.

Experts suggest that the origin or evolution of the fishes in the Himalayas and north-eastern parts of India must have been the consequence or after-effects of orogenic events (geological movement) at various stages in the Himalayas’ uplift. Detailed surveys can provided valuable information about the evolutionary trends and many rare groups of fishes can be discovered.