One of eight global World Heritage Sites designated by the United Nations Educational, Scientific and Cultural Organization, the Western Ghats is a chain of mountains that runs parallel to the west coast of peninsular India. Biologists studying the Western Ghats know it as a biodiversity hotspot in southwestern India that “contain(s) more than 30 per cent of all plant, fish, herpetofauna, bird, and mammal species found in India” (Western Ghats Region ).
For those unfamiliar with the word, “herpetofauna” is a zoo- logical term referring to the reptiles and amphibians of a given region. One of the herpetofauna species that is endemic to the Western Ghats, the Travancore tortoise (Indotestudo travancorica), one of three recognized species in the genus Indotestudo.
George Albert Boulenger (1858-1937), a Belgian-British zoologist and botanist, scientifically described and named the Travancore tortoise (I. travancorica) in 1907. Its common name refers to the Travancore royal family that ruled the region to which it is native from 1729 until 1949. Soon thereafter the territory became the modern Indian state of Kerala.
The other two members of the Indotestudo genus are Forsten’s tortoise (I. forsteni), and the elongated tortoise (I. elongata). In the chelonian community some disagreement exists because, while some researchers use the species name travancorica, others contend that the Travancore tortoise is best classified as a member of the species I. forsteni.
Some scientists believe that Forsten’s tortoise is an introduced Travancore tortoise that has genetically evolved. Molecular variation studies of the Indotestudo complex are ongoing and are may well settle the argument by confirming the relationship of these currently recognized species (McDougal and Castellano, 1996).
Chelonian researchers describe all three Indotestudo species as “Asian forest tortoises.” The Travancore tortoise is native to southwestern India, Forsten’s tortoise occurs on the Indonesian islands of Sulawesi and Halmahera, and the elongated tortoise occurs in various nations in Southeast Asia. Some researchers believe it is endemic to northeastern India, but this is open to dispute.
Because it is not well-studied in habitat, comparatively little is known about the Travancore tortoise in the wild. Chelonian scientists conducting studies of the species in habitat find it to be a challenging study subject because the tortoise is elusive by nature, superbly camouflaged in habitat, and has an excellent sense of hearing (Lenin, 2020).
Although it is fairly rare in captivity, much of what is currently known about the tortoise, particularly about its reproductive activities, is based on observations of captive animals. There are no recognized subspecies of the Travancore tortoise.
While I. travancorica resembles I. elongata to a remarkable degree, the two species are not sympatric, that is, they do not occur in the same geographical area. The Travancore tortoise occurs only in southwestern India, however, the elongated tortoise is primarily native to Southeast Asia and possibly occurs only in northeastern India. Therefore the geographic location of a given individual is a reliable indicator of its species.
A member of the Testudinidae family of tortoises, the Travancore tortoise is a medium- to large-sized species growing to a carapace length of 13 inches (33 centimeters) with an elongated, moderately flattened shape. The coloration of the carapace, typically brown scutes with irregular black blotches, provides camouflage that enables the tortoises to blend well with the leaf litter (the decomposing leaves) on the forest floors in their ecosystems. The hatchling emerges from its egg with a carapace that is brown and nearly spherical in shape.
The species’ plastron coloration is similar to that of the carapace: each scute is brown marked with a large, irregular black patch. The head of I. travancorica is cream or pale yellow with the skin around the eyes and snout tinged with pink in both male and female tortoises. A deeper pink coloration appears on the head of adult males during courtship and mating. The head of the female also shows a slightly more pink tint. Local researcher Madhuri Ramesh observes that during mating season males develop large pink circles around their eyes that look “like badly applied make up” (Lenin, 2020).
Displaying moderate sexual dimorphism, the species’ male has a plastron that is noticeably more concave than that of the female. His “tail ends in a claw-like, curved spur”. The female’s plastron is comparatively flat, and her tail terminates in a small, conical, keratinized tip (Mital, 2020).
Range and Habitat
Native to the Western Ghats mountain range, the Travancore tortoise ranges through the Indian states of Karnataka, Kerala, and Tamil Nadu in southwestern India at elevations of 328 to 3,281 feet (100 to 1,000 meters) above sea level. The type locality is near Trivandrum, Travancore Hills, (Mital, 2020).
According to Madhuri Ramesh, I. travancorica prefers the microhabitats near “brook beds, stream banks, and swamps” (Lenin, 2020) in “evergreen, semi-evergreen, moist deciduous and bamboo forests” within its range. It also inhabits teak and rubber plantations (Mital, 2020). Using cover types such as lantana shrubs, bamboo thickets, underneath grasses, fallen logs, lianas, inside tree holes, rock holes, and termite hill burrows makes detection of tortoises for study difficult (Vasudevan, et al., 2010).
Although the species is sometimes described as diurnal (active in daytime) rather than nocturnal (active at night), the Travancore tortoise is in actuality crepuscular, that is, it emerges from hiding at twilight to forage in the “dull light” of late afternoon which offers some protection from predation (Lenin, 2020).