Over 100 species of snakes have been reported in the Western Ghats of southwest India, one of the most isolated sky island systems in the Oriental tropics. With its peak towering to 2,533 metres at Mount Vandaravu, the Palanis are a prominent massif south of the Palghat gap. Wedged between the highest point south of the Himalayas—the Anaimudi peak—to the west and the farthest end of the Eastern Ghats—Sirumalai—to the east, the sprawling Palani Hills complex offers a great deal to biodiversity, including snakes. With a rich tapestry of habitats and landscape features, the Palani Hills offer herpetologists looking to explore the wild a worthwhile experience.
The first scientific study on the snakes of this region seems to have commenced from the work of the indefatigable Colonel Richard Henry Beddome (1830–1911), who published some of the earliest known snake descriptions from this precise locality. The first of these is perhaps the large-scaled green pit viper, Trimeresurus macrolepis, which he described in 1862. Soon afterwards he detailed the Palani shieldtail snake, Uropeltis pulneyensis, in 1863. In 1877, Beddome wrote about another new snake, the Madurai shieldtail, Platyplectrurus madurensis. This was the first time ‘Kodiukarnal’ was first mentioned in a herpetological work. Further on, he described a few more shieldtails from the eastern offshoots of the Palani Hills: Uropeltis broughami and its synonym, that is, a description of the same species under another name, Silybura levingi. He also described another snake from the Palanis, Silybura nigra, in 1878—now known as the Woodmason’s shieldtail, or Uropeltis woodmasoni, described by William Theobald (1829–1908) in 1876.
After Beddome’s work, two independent studies on snakes were conducted more or less simultaneously in the 1920s. The first that is dealt with here is that of Colonel Frank Wall (1868–1950). Perhaps the most prolific herpetologist of his time, Wall visited Shenbaganur in the Palani Hills and researched snakes, aided by collections made by a Reverend L. Anglade. First, Wall detailed another new species of shieldtail in 1921, Teretrurus rhodogaster. A year later, he expanded the description of the same species based on a fresh batch of specimens. In 1922 and’23, Wall published two articles on the snakes of Shenbaganur, again, aided by Anglade’s collecting. He reported on the shieldtail species Beddome had written about as well as the following: the narrow-headed snake, Xylophis perroteti, later described as X. mosaicus; the striped keelback, Amphiesma stolatum; the black-spotted kukri snake, Oligodon venustus; and the ornate flying snake, Chrysopelea ornata.
Secondly, the Swiss herpetologist Jean Roux (1876–1939) of the Natural History Museum of Geneva, Switzerland, conducted an expedition in the Palani Hills, among other massifs in the Western Ghats. In 1928, Roux published his work, in which he recorded Beddome’s worm snake, Gerrhopilus beddomii; the three kinds of shieldtails that Beddome described; the narrow-headed snake, Xylophis mosaicus; the Travancore wolf snake, Lycodon travancoricus; and Gunther’s vine snake, Ahaetulla dispar. He also recorded common pan-Indian snake species like the rat snake, Ptyas mucosa, the striped keelback, and the olive keelback, Atretium schistosum, from localities such as Marian Shola, Maryland, Kukkal, and Poombarai. Roux’s work remains to date the most detailed publication on the reptiles, barring snakes, and amphibians of the Palani Hills.
Over half a century later, in 1985, Dr M V Rajendran published a monograph on shieldtail snakes. In this work, he dealt with all four species of shieldtail snakes that Beddome and Wall described, based on fresh snake collections made in Shenbaganur and Kodaikanal. Dr Rajendran conducted one of the most detailed ecological studies on these snakes. Wall had, indeed, penned extensive morphological and natural history notes, including breeding, young, feeding, gut contents, and so on. However, Rajendran’s exhaustive information on the microhabitats of the locations where he found these burrowing snakes, feeding trials in semi-captive conditions, and other such little-known and minute ecological parameters, including pH and soil hardness, make this an outstanding and unique work.
There is a very special paper, ‘A New Species of Oligodon from the Palani Hills, South India’, published by Romulus Whitaker and Shekar Dattatri in 1982. If the High Wavy Mountains of the Theni district have their renowned Hutton’s pit viper, then the Palani Hills have this snake as their crown! Nikhil’s kukri snake, Oligodon nikhili, is one of the most poorly known species of snakes in South Asia. (Read Nikhil Whitaker’s piece in our ‘Children’ section, this month.) On par with Hutton’s pit viper, Nikhil’s kukri is definitely known only from its type specimen—the very specimen based on which the snake was first described and named new to science. This snake has a curious story; the only known specimen was first spotted as it was crawling under a cement slab in the Tiger Shola forest patch in Shenbaganur, by a four-year-old Nikhil Whitaker, son of the first author who described this species. It is understood to be closely related to another Western Ghats–endemic kukri snake, Oligodon brevicaudus.
Subsequently, T S N Murthy of the Zoological Survey of India, Madras, had collected and published on some shieldtail snakes from Kodaikanal. But for these few short notes, no major work has been done recently on the snakes of the Palani Hills. In 2014, as plans to designate and declare the forests of the Palani Hills a Kodaikanal wildlife sanctuary were about to eventuate, I was part of a rapid biodiversity inventory commissioned by the Forest Department of the Kodaikanal and Dindigul Forest Divisions.
Between mid-2014 and early 2015 (this work followed a hiatus of many decades since the last works by Dr Rajendran), surveys were conducted in different habitat types, such as the disturbed and humanised plantation areas of peripheral Kodaikanal, Shenbaganur, and Perumal Malai, as well as the relatively undisturbed montane grasslands and shola forests in Nattampatti/Vandaravu, Mannavanur, Pillar Rock, Kukkal, Poombarai, Berijam, Mathikettan Shola, Thandikudi, and Asankodai, to name a few. Among the species that were sighted were common non-venomous snakes, the endemic shieldtail snake species mentioned above, and the rare Beddome’s worm snake, plus a few endemic keelbacks, tree snakes, and water snakes. Sadly, roadkill of these snakes was also present. I was fortunate to have sighted a rare albino shieldtail snake, and Nikhil’s kukri tantalised me, as expected.
Looking back, there has been a fair amount of work on snakes done over the decades in Kodaikanal, and the Shenbaganur Museum of Natural History stands as a testament. I have spent time in the museum just gawking at their mouth-watering specimen collection, which is full of rare and endemic species, secured in glass cabinets. In places like the Palani Hills, it is not uncommon to meet renowned experts in this field. One time, I met a respected senior colleague, the herpetologist and biogeographer Dr S P Vijayakumar—one of the earliest modern-day scientists to have studied the herpetofauna of the Palani Hills, in the 1990s.
Thanks to over a century’s work in herpetology, Kodaikanal has a remarkable body of work to be proud of. However, I believe that this is just scratching the surface. There is a lot more work to be done. Being the unique biosphere that it is, there are snakes in the Palanis that only exist here and nowhere else, and we currently know only their names and what they look like.
We, the larger herper community, need a whole new generation of nature lovers to take up deeper work in this largely unknown space so that we can learn more about the endemic species’ biology and natural history and preserve the snakes of the Palanis for posterity.