chelonians

Sri Lanka is one of those countries in the world that could boast of having the 3 major types of chelonians, the freshwater terrapins, land tortoises and marine turtles. (The word ‘turtle’ is commonly used for all chelonians, despite the habit).

All tortoises are turtles

But not all turtle are tortoises

All terrapins are turtles

But not all turtles are terrapins

Some turtles are just turtles !

- Indraneil Das

Freshwater terrapins

Sri Lankan freshwaters harbors three species (four with subspecies) of freshwater terrapins, out of which one sub-species, Parker’s black turtle Melanochelys trijuga parkeri, which is considered to be the rarest fresh water turtle in the country with only few scattered records, is the only endemic taxon. It is mainly known from the northern areas of the country. It differs from the hard-shelled terrapin or the Black turtle (Melanochelis trijuga thermalis), the only other sub-species present in the country, in its large size and the shape of the carapace. M. t. thermalis is very common and is distributed throughout the island except at highest altitudes and inhabits a wide range of habitats including paddy field and ditches in town areas. The Soft-shelled terrapin or Flap-shell turtle (Lissemys punctata) is mainly found in the lowlands but also occupies some water bodies in the hills. When disturbed it hides under mud and among aquatic vegetation. Both species are intensively hunted for flesh. All terrapins act as natural scavengers, which is very important. The Red-eared terrapin or Red-eared slider (Trachemys scripta), is an ‘alien’ species of terrapin which has established a stable population in several large water bodies, mainly around Colombo. It is considered to be one of the world’s worst Alien Invasive Species, and these populations are considered to be formed by escaped or released specimens, as it is kept as a pet in many houses. This terrapin, which can easily adapt to natural conditions, can do a great damage to aquatic ecosystems and the juveniles of the species are known to carry the Salmonella bacteria.

Family Bataguridae

Genus : Melanochely Gray, 1869

Melanochelys trijuga parkeri Deraniyagala, 1939; Parker's Hard-shelled Terrapin, Parker's Black Turtle (E) ; Parkerge Gal Ibba (S) Endemic sub-species
Melanochelys trijuga thermalis (Lesson,1830) ; Spotted Hard-shelled Terrapin, Spotted Black Turtle (E) ; Gal Ibba (S)

Family Trionychidae

Genus: Lissemys Smith, 1931.

Lissemys punctata punctata (Lacepede, 1788) ; Soft-shelled Terrapin, Flapshell Turtle (E) ; Kiri Ibba (S)

Family Emydidae

Genus: Trachemys

Trachemys scripta ; Red-eared Slider (E) ; Rathukan Ibba (S)

The land tortoise

Sri Lanka has only one terrestrial chelonian, the Star tortoise (Geochelone elegans), which is considered to be one of the most beautiful tortoises in the world. It is primarily restricted to the dry zone of the 1^st peneplain of the country ( from sea-level up to 270m a.s.l.), but there are records from the second peneplain as well, which may however be based on escaped specimens, as it also makes a famous pet. It’s naturally found in scrub jungles with open grass tracts.

Family : Testudinidae

Genus: Geochelone Schoepff, 1792.

Geochelone elegans (Schoepff,1795) ; Indian Star Tortoise (E) ; Mevara Ibba / Tharu Ibba (S)

Marine turtles

Five out of seven marine turtle species in the world occur in the waters around Sri Lanka. They come ashore to lay eggs at different times and places but few places, such as Rekawa, Bundala and some locations in Jaffna peninsula, are known to have all five species. The five species of marine turtles found in the country are; Green Turtle (Chelonia mydas), Hawksbill Turtle (Eretmochelys imbricata), Loggerhead Turtle (Caretta caretta), Olive Ridley Turtle (Lepidochelys olivacea) and the Leatherback Turtle (Dermochelys coriacea), which is the world’s largest and the most endangered sea turtle. Sea turtles are under threat by over-harvesting of both eggs and adults and from accidental mortality in the nets and long-lines of fishing fleets. Furthermore, Hawksbills have also been hunted for centuries for their shells, which are the sole source of tortoiseshell for jewellery and ornaments. Despite their protection under international and national laws, there is still a disturbingly large amount of illegal trade in tortoiseshell and other hawksbill products, and this probably still constitutes a major threat to them.

Family Chelonidae.

Genus: Caretta Rafinesque

Caretta caretta (Linnaeus, 1758) ; Loggerhead Sea Turtle (E) ; Olugedi Kasbaeva (S)

Genus: Chelonia Latreille

Chelonia mydas (Linnaeus, 1758) ; Green Turtle (E) ; Gal Kasbaeva (S)

Genus: Eretmochelys Fitzingr

Eretmochelys imbricata (Linnaeus, 1766) ; Hawksbill Sea Turtle (E) ; Pothu Kasbaeva (S)

Genus :Lepidochelys Fitzinger, 1843.

Lepidochelys olivacea (Eschscholtz, 1829) ; Olive Ridley Sea Turtle (E) ; Batu Kasbaeva (S)

Family : Dermochelyidae.

Genus: Dermochelys Blainville, 1816

Dermochelys coriacea (Vandelli, 1761) ; Leatherback Sea Turtle (E) ; Dara Kasbaeva (S)