About the size of a human palm, the reptile was not easy to find: It's active at night, dwells on vertical cliffs, and looks a lot like its close relatives.
In 2014, Zeeshan A. Mirza and David Raju were crawling through caves and thick forest near a hill station looking for another type of gecko.
“The area is dominated by bears and gets quite scary at night,” says Mirza, an independent wildlife biologist.
Then, the team saw a pale brown lizard with white and dark brown spots on its back running up a wall near the road. An expert in this gecko group, called the Brooke's complex, Mirza knew right away he had discovered a new species. (Read "New Gecko Sheds Skin on Demand, Looks Like Raw Chicken.")
“Catching geckos can be a challenge because they are great escape artists, easily disappearing into thin cracks or other inaccessible places in the dark,” Aaron Bauer, a biologist at Villanova University in Pennsylvania who was not involved in the study, says by email.
But Mirza struck gold and brought home five of them. “Their eyes reflect torchlight even from a distance, which gives them away,” says Mirza, whose study appeared recently in the journal Amphibian & Reptile Conservation.
Back at the lab, Mirza compared the specimens' DNA with seven other distinct species in the Brooke's complex. Sure enough, the genetic research revealed a new species, Hemidactylus chipkali. Chipkali is a commonly used Hindi word for lizard.
H. chipkali is unique in that its legs are more slender than its relatives, and it has fewer lamellae—thin, plate-like structures that provide for its clingy toes. ("Geckos May Be Famously Sticky, but Here's What Stumps Them.")
So far, the gecko has not been found outside of the tiger reserve, so its population size is unknown.
“Although it may be threatened by a number of human activities, it is likely that the species is in no immediate danger,” says Bauer, who studied geckos worldwide for more than three decades.
“Except on islands where novel predators are introduced, most geckos tolerate a good deal of threat,” he adds: Their small sizes, nocturnal habits, and ability to hide serve them well.
Even so, study leader Mirza says the new gecko's discovery shows the need for protected areas in other parts of India.
“It’s also time more funds are released for those who want to study regions other than the usual biodiversity hot spots, the Western and Eastern Ghats."
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