Stunning New Geckos Described From South India
With the discovery and description of the Bangalore geckoella and Rishi Valley geckoella from the Mysore plateau, India adds two new endemic species to its biodiversity inventory.
Photo: Ishan Agarwal.
What do you gift your mother on her 60th birthday to express how much she means to you? Well, if you’re Ishan Agarwal, you give her the honour of having a new species of gecko named after her. In November 2016, Agarwal, a post-doctoral research fellow at the University of Villanova in Pennsylvania, described not one but two new geckos from India’s Mysore plateau in the journal Zootaxa. The Bangalore geckoella Cyrtodactylus srilekhae, named after the herpetologist’s mother, and the Rishi Valley geckoella Cyrtodactylus rishivalleyensis, named after the school he attended growing up, are only the second and third species of Cyrtodactylus, a genus of bent-toed geckos, to have been described from mainland India in over 130 years! Both new species are endemic to the country, and have highly restricted ranges that are limited even within the Mysore plateau.
Agarwal’s interest in lizards was cemented as a college freshman in 2002, when he came across the stunning little Deccan ground gecko Geckoella deccanensis while out on a hike. Five years later, he found the flattened remains of a gecko that he couldn’t identify on the road by his mother Srilekha Agarwal’s house. In the years that followed, as Agarwal pursued his PhD on the biogeography and systematics of Indian bent-toed geckos from the Centre for Ecological Sciences at the Indian Institue of Science, he painstakingly combed through the deciduous and scrub forests around Bengaluru in order to collect enough specimens to make his case that this was a new species. Cyrtodactylus srilekhae’s range is restricted to within 60 km. of Bengaluru city, and is befittingly named after the woman who nurtured Agarwal’s interest in the natural world and in whose backyard it was first found.
Photo: Ishan Agarwal.
Even as he was searching for specimens of the Bangalore geckoella, Agarwal’s fellow PhD students at the Centre for Ecological Sciences brought him another gecko, a juvenile that didn’t seem to fit the mold of any existing species and whose DNA suggested that it was unique. Intrigued, Agarwal ventured into the isolated hill ranges around Rishi Valley, Andhra Pradesh, where it was collected from, to investigate. Here, he was elated to discover a new species of gecko, less than six km. from his alma mater Rishi Valley School, where his love for the Great Outdoors had found substance. Cyrtodactylus rishivalleyensis has an even more restricted range than the Bangalore geckoella and is only known from above 1000 m. in its type locality of Reserved Forest on that one isolated hill range.
Finding a new species may just be easier than describing one. It took Agarwal and his colleagues several years to organise collection permits from the Karnataka and Andhra Pradesh Forest Departments, and then collect enough individuals to describe the new species and get the descriptions peer-reviewed and published. By the time the species descriptions met the requirements of the International Code for Zoological Nomenclature, the body that governs the naming of species, it had been nine years since he had first seen the Bangalore geckoella and six since he saw his first Rishi Valley geckoella. “Publishing these new species descriptions was challenging for a number of reasons. One, members of this group are very similar in morphology and lack many of the characters used to differentiate gecko species. Secondly, the two described members of this complex, Cyrtodactylus collegalensis and C. speciosus, were known from a single specimen each, both of which were in the Natural History Museum (NHM), London. I wasn’t able to visit the NHM during my PhD, and it took many years for me to arrange collaborations with people who could examine those specimens,” says Agarwal. Interestingly, through this process, Agarwal had the support of his PhD supervisor Praveen Karanth, and Sanctuary Award winner Varad Giri, after whom Agarwal named another geckoella species, Cyrtodactylus varadgirii, that he had co-discovered in Mumbai in 2016.
Photo: Ishan Agarwal.
Geckoella is endemic to India and Sri Lanka, a subgenus of the genus Cyrtodactylus which falls under Gekkonidae, the largest family of geckos in the world. The two new species described by Agarwal are members of the Cyrtodactylus collegalensis complex, and sport completely smooth, granular scales on the dorsum, and striking chocolate and cinnamon patterns that are characteristic of this group. However, the colour patterns, morphometric ratios and mitochondrial DNA sequence of each member species is distinct.
The recent discoveries indicate that there are still new species to be found and described in the country. In fact, an astonishing 17 new species of lizards have been described from peninsular India since 2014, with three endemic geckos discovered within the vicinity of Bengaluru alone. Unfortunately, many of these are vulnerable to anthropogenic pressures and could potentially be lost even before they’re found. “India is a lot more diverse than is currently thought, and most species, both known and undescribed, face high risks due to habitat loss. If conserving biodiversity is our goal, the priority has to be on broad scale collections across taxonomic groups. This way we can know just how many species we have and where they are,” says Agarwal.
Author: Cara Tejpal.