6 new lizards discovered in Northeast forests

In what has added to rich wildlife treasure of Northeast, a team of scientists has discovered six new species of bent-toed geckos (lizards) from different parts of northeast India.

Informing that these bent-toed geckos of the genus Cyrtodactylus are the most species-rich genus of geckos globally with over 250 species, the spokesperson of team Ishan Agarwal said, "The new Indian species have been named after the Assam capital, Guwahati, as Cyrtodactylus Guwahatiensis, or the Guwahati bent-toed gecko, making it the fifth lizard to be described from a major Indian city, the others being Bengaluru, Delhi, and Mumbai."

"Similar one is named after Nagaland as Cyrtodactylus Nagalandensis, another as Cyrtodactylus Kazirangaensis after the famed Kaziranga National Park, and the largest bent-toed gecko is named as Cyrtodactylus Jaintiaensis after the Jaintia Hills of Meghalaya," he added.

The other two are Cyrtodactylus Montanus after the Jampui Hills of Tripura and another one named Cyrtodactylus Septentrionalis of the Abhayapuri bent-toed gecko, said Mr Agarwal.

The description of these six newly discovered species has been published recently in the peer reviewed taxonomic mega-journal, Zootaxa, published from New Zealand.

The team of scientists comprised Ishan Agarwal, Varad B. Giri, R. Chaitanya, Stephen Mahony of Natural History Museum, London and global authority on geckos, and Aaron Bauer of Villanova University, US.

"An adult female was collected from the vicinity of Tyrshi Falls near Jowai town in West Jaintia Hills district of Meghalaya by Tarun Khichi, Aniruddha Datta-Roy and Ishan Agarwal on  November 15, 2010. The species is only known from the vicinity of Tyrshi Falls, in the Jaintia Hills. The geckos were spotted at night by eye-shine on vertical rock faces," the journal said.

The team used mitochondrial sequence data to identify divergent lineages within the gekkonid genus Cyrtodactylus in Northeast India besides morphological data to describe six new species from within the Indo-Burma clade of Cyrtodactylus. "The new species share an irregular colour pattern but differ from described species from the region in morphology and mito-chondrial sequence data," it stated.

"The description of these six new species brings the total number of Cyrtodactylus in the Himalayas and mainland Indo-Burma to 56, including 15 Indian species. This makes Cyrtodactylus one of the most micro-endemic groups of terrestrial vertebrates in the region, as is the case for the genus across much of its range," it added.

Team member Varad Giri said that just six species of these geckos were known from the Himalayas and northeast India, but in the past few months, nine new species have been described including four and 11 from these two regions respectively.

Neighbouring Myanmar has also witnessed a huge increase with over 20 new species discovered since 2017 and is the outcome of surveying areas never sampled before within the Indo-Burma biodiversity hotspots.

Though, all these species hail from a single locality each, nothing is known of their natural history, ecology and distribution, except that they are nocturnal creatures living in rocks.

Mr Agarwal feels that they are likely to be a narrowly distributed endemic species and northeast India may have several dozen more bent-toed geckos.