The spot-necked day gecko and the Anaimudi day gecko, both very distinctly-patterned lizards found only in the higher reaches of the Agasthyamalai and Anamalai hill ranges in the Western Ghats, are the latest additions to India's reptile fauna.
Researchers including Vivek Philip Cyriac of the Indian Institute of Science Education and Research Thiruvanathapuram (IISER-TVM) were surveying reptiles in Kerala's Shola National Parks in 2013 when they came across a predominantly greyish-brown-coloured gecko.
Red iris
The approximately six-centimetre-long lizard sported an unusual, bright red iris (a thin band surrounding the pupil of the eye) and a long, striking amber line also ran down its dark back: unlike anything the team had seen.
“We thought it could be a new species, but we had to make sure,” said Cyriac.
So the team collected and studied the geckos’ morphology in detail. The features they studied included the lengths of various body parts such as tail and fingers, lamellae (fine, plate-like structures on the base of gecko feet that help them scale vertical surfaces) and tubercles (tiny raised projections on their bodies). They compared these with the morphology of other similar-looking lizards to establish Cnemaspis anamudiensis or the Anaimudi day gecko, as a new species.
Spot-necked day gecko
The team (including scientists at the Zoological Survey of India and National Centre for Biological Sciences) utilized the same method to describe yet another day gecko they spotted at Kollam's Shendurney Wildlife Sanctuary – which is part of the Agasthyamalai hill range – in 2016. This gecko had bluish-white spots in a distinct ‘necklace-pattern’ on its nape. While this differentiated the species from the similar-looking Ponmudi day gecko and the Bedomme’s day gecko, the lack of enlarged flat tubercles on its tail was one of the features that ruled out its possibility of being the ornate day gecko. The team named the new species Cnemaspis maculicolis or the spot-necked day gecko.
Both these diurnal geckos are currently known only from single localities in high-elevation forests located at more than 1,200 metres above mean sea level in the Ghats. There is a possibility that these day geckos could be present in the surrounding hills but more detailed surveys would be required to confirm this, said Cyriac.
While mountain ranges in general have a rather high diversity of such day geckos, the “accelerated environmental decline” that these regions face are a concern, he added.
