A decade of discoveries

April 27, 2020

A decade of discoveries

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In the last 10 years, 15 new species of snakes and geckos have been described from India, highlighting the fact that our reptilian diversity is poorly studied and deserves all the attention it can get. In this issue, we present an account of the discovery of an exciting new species of leopard gecko from the Satpura hills in Madhya Pradesh.

It was quite some time ago when I reviewed the available literature and images of the leopard gecko species found in India—with a particular interest in the Western Indian leopard gecko (Eublepharisfuscus). I noticed then that an image sent to me from Melghat Tiger Reserve did not match any of the known species of the genus reported from India. As it turns out, this was just the beginning of a mystery that eventually led to the discovery of a new species!

Given that only an image was available at that point, it was not possible to identify the species; and I had almost forgotten about the gecko, until Aatish Gawai, a reptile enthusiast, keen naturalist and good friend, sent me pictures of another individual clicked near Melghat Tiger Reserve. This rekindled my curiosity, and the search for this unidentified gecko took me to the Satpura hills. David Raju, a brilliant naturalist who has described several species of frogs from the Western Ghats, showed me images of a leopard gecko from Pachmarhi, Madhya Pradesh, which matched the ones from Melghat. He suggested that we could visit the area where he had photographed the gecko and try to find them—exactly what I was hoping to do! We procured the necessary permissions from the forest department of Madhya Pradesh, who were keen on the prospect of finding a new species and eager to help. I was thrilled that we were possibly heading to find a species completely new to science, but grew nervous as we reached a place where we had to work during the night in a landscape dominated by Sloth bears.

The newly discovered E. satpuraensisis currently known from only a few locations in the Satpura hills in Madhya Pradesh and peripheral areas of Melghat TR in Maharashtra. Field nights Rajesh Sanap – a fellow herpetologist –David and I left for Pachmarhi, located in the heart of Satpura hills in the Satpura Tiger Reserve. This was my first visit to these mysterious hills, which has recently been recognised as an important biogeographic realm. On the first day, we explored the caves where the gecko was known to reside in, but had no luck during the day or night. But it was not a complete waste. We found two very interesting scorpions –Hottentottajabal purensisand Scorpiopspachmarhicus. The former was only known from a few preserved specimens ,and my photograph from the night is probably the first ever picture of a live specimen of this species. All members of the genus Scorpiops are found in the Himalayan hills, except S. pachmarhicus ,which is endemic to central India.
Besides these, we even found a trapdoor spider, which in all likelihood is an undescribed species. Despite such rewarding sightings, we were dejected that the particular gecko we were looking for had eluded us.
Leopard geckos are strictly nocturnal and very shy. They only move about after dark and mostly live around large boulders and caves, the latter being the preferred abode of Sloth bears .Sloth bears are known to be aggressive towards intruders and this made our night surveys extremely dangerous. On our second night, we found a sub-adult gecko moving actively on a large boulder.
This was a huge boost for us after the disappointing first night. We continued looking, and soon, Rajesh spotted a large individual peeping from a cavity between two large boulders, retreating into the narrow gap as we approached. The next night was fantastic. We found one large individual, a few sub-adults and a juvenile gecko—all as we started!
Searching for about three hours, we covered a huge distance, partially on foot and partially driving through the undulating landscape. I crouched into small caves and large burrows to see the signs left by the daytime inhabitants of these homes – bears and porcupines. We could barely stand in these small gaps, so in case anything was hiding inside, running was not an option. After we had seen over 10 individuals of the gecko and not a single bear, we decided to call it a night. But there was one last surprise in store for us. As were driving away, Rajesh spotted a small gecko crossing the road in front of our vehicle. To our amazement, it was a ground-dwelling gecko of the genus Geckoella. Geckoella geckos, known as bent-toed geckos commonly, are small-sized, handsomely marked, and distributed across the Indian peninsular region.
Some other interesting finds during the survey:

Hottentota jabalpurensis, an endemic scorpion of central India and probably the first photographic record of a live specimen

A trapdoor spider which most probably is an undescribed species

Scorpiops pachmarhicus, the only species of Scorpiops found in peninsular India In the lab
After the successful field visit, I returned to my institute to compare our findings with the available literature. To our amazement, the characters did not match any of the five known species of the genus Eublepharis. This was indeed great news for the entire team. At times, however, descriptions can either be wrong or misinterpreted. Hence, it is good practice for a taxonomist to compare the findings with museum specimens for confirmation. Rajesh and I visited the head office of the Zoological Survey of India in Kolkata, and we compared the gecko we found in Satpura with the ones they had in their collection. We did the same with those housed in the collection of Bombay Natural History Society in Mumbai. David visited ZSI’s branch in Jabalpur and discovered five specimens from Satpura hills, which further helped in confirming our observations and findings. Additional help from the curator of the herpetology section of the California Academy of Science helped in comparing our species with the remaining species of geckos.
After a month-long background study, we finally concluded that the gecko from Satpura hills was indeed a new species. We named it Eublepharissatpuraensis ,after the habitat it was discovered in. The paper we jointly wrote was submitted to the journal Phyllomedusain October2014, which was published recently in January 2015.
The discovery of this large and handsomely marked gecko, which was previously misidentified, highlights the need for dedicated surveys across the country. My colleagues and I have been responsible for describing three new species of geckos in the year 2014,pointing out that reptile diversity has been poorly documented in our country. Technology and its availability have improved enormously over the year sand I feel that this is just the beginning of the golden era in the taxonomy of herpetofauna. Surely, there are several more species awaiting discovery! Trivia 1 : Only geckos belonging to Eublepharidae (leopard gecko) family have eyelids, all others lack them.
2 : The English word ‘gecko’ comes from the Latin word ‘gekko’, which in turn comes from an Indo-Malayan word ‘gekoq’ – an imitative of the sound certain species of geckos make.
3 : Most geckos cannot blink. They often lick their eyes to clean them and keep them moist.
4 : The eyes of nocturnal geckos are up to 350 times more sensitive than human eyes!
Recent gecko discoveries from India
India, with about 570 known species, is extremely rich in reptilian diversity. Malcolm A. Smith’s three volumes on reptiles on Indian subcontinent in ‘The Fauna of British India’, laid a solid foundation for reptile studies in the country and till date remains the most extensive work published on reptiles of the subcontinent. Further advancement in sciences and technology has afforded a different perspective to recent taxonomists – an opportunity to look into greater details, which was unavailable at the time of Smith. The use of molecular tools has served to delimit species based on distribution, ancestry and many other factors. Here are some of the most recently described geckos from India:
Cnemaspisgirii

This little gem, found in the ravines around Kaas plateau in the Satara district of Maharashtra, is barely two inches in length. It lives under boulders and in tree hollows in stream forests. Members of this genus have rounded pupils unlike most other geckos, which have vertical pupils. This species differs from other members of the genus as it lacks the spine like scales on its flanks; it is also different with regards to the number of pores present under the thighs of the males. My colleagues and I named it after Dr. Varad Giri for his immense contribution to Indian herpetology.

Hemidactylusacanthopholis

I described this species along with my colleagues in the year 2014. Surprisingly, it was not found on a survey in some forest, but on a research visit to the Natural History Museum at London! This species was identified as a Giant rock gecko (Hemidactylus maculates), which is apparently a widespread species complex. Only after comparison with the relevant specimens in the museum, was it concluded as a new species. We named it after the large, spine-like tubercles on the gecko’s back. Almost nothing is known about this gecko except that it is found in the dry parts of Tamil Nadu.

Hemidactylussataraensis

This beautiful little reptile dwells on the harshand barren lateritic Chalkewadi plateau ofSatara, Maharashtra. It was described asrecently as in 2008. Till date, it remains knownonly from the type locality, restricted to anarea less than 8 sq. km. It is handsomelymarked and stoutly built and lives under rockson the plateau.

Cnemaspiskolhapurensis

This tiny lizard from the Western Ghats was describedin 2009, from the Kolhapur district of Maharashtra. Thisspecies lives under boulders and forages in the leaf litter.What is unique to this species in the genus is that the backscales are homogenous, i.e., they are of the same shapeand size, while most other species of the genus haveheterogenous scales. This ground-dwelling gecko displaysa dazzling iridescent sheen on its tail.

Hemidactylusaaronbaueri

This large-sized gecko reaches a staggeringtotal length of 22 cm. It inhabits hill forts andcave systems on the northern Western Ghats ofMaharashtra. Cryptically-coloured with dark and lightundulating bands, the gecko easily merges with itssurroundings. The species was described in 2008,and named after Aaron Bauer, an authority on geckos of the world.