Myuchelys latisternum (Saw-shelled Turtle)

Myuchelys latisternum, commonly known as the Saw-shelled Turtle, is a freshwater species native to Australia. It is known for its serrated carapace, which gives it a saw-like appearance, and its ability to tolerate diverse aquatic environments.

Scientific Classification

Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Testudines
Family: Chelidae
Genus: Myuchelys
Species: M. latisternum

Common Names

Saw-shelled Turtle
Broad-shelled Turtle

Identification

Description

This species has an oval carapace with serrated edges at the rear, giving it a saw-like appearance. The shell color varies from dark brown to olive-green, often covered in algae. The plastron is lighter, usually yellowish with dark markings. The head is broad with a short snout, and the skin is grayish-brown with yellow streaks along the neck.

Sexual Dimorphism

Females are larger than males, reaching up to 28 cm in carapace length, while males typically stay under 18 cm. Males have a longer, thicker tail, whereas females have a shorter, more rounded tail.

Native Origin and Distribution

Geographical Range

The Saw-shelled Turtle is found in eastern Australia, from Cape York in Queensland down to northern New South Wales. It inhabits both coastal and inland freshwater systems.

Preferred Habitat

This turtle thrives in slow-moving freshwater environments like rivers, creeks, swamps, and lagoons. It prefers habitats with abundant vegetation and submerged logs for hiding and basking. It can also tolerate brackish water.

Behavior

Feeding Habits

Saw-shelled Turtles are opportunistic omnivores, feeding on aquatic invertebrates, small fish, amphibians, carrion, and plant matter. They are known for preying on the invasive Cane Toad, as they appear to have some resistance to its toxins.

Predators

Juveniles face predation from birds, fish, and larger reptiles. Adults have fewer natural predators but may fall victim to large fish, crocodiles, and feral animals like foxes.

Reproduction

Breeding Season

Mating typically occurs during the warmer months, from spring to early summer. Nesting usually takes place between October and January.

Reproductive Method

Females lay clutches of 8–14 eggs in sandy or loamy soil near water bodies. Incubation lasts about 50–80 days, depending on temperature. Hatchlings emerge in summer and make their way to the water.

Conservation

Extinction Status

Listed as Least Concern by the IUCN, but local populations may be declining.

Threats

Habitat destruction, pollution, and predation by invasive species like foxes and cats are primary threats. Illegal collection for the pet trade also affects some populations.

Conservation Measures

Protecting wetland habitats and implementing predator control programs help maintain stable populations. Public awareness and conservation efforts focus on reducing human impacts on their ecosystems.

Economic Importance

This species plays a role in controlling aquatic pests, such as invasive fish and amphibians. It also has some value in the pet trade but is less common than other turtle species.

Interesting Facts

Saw-shelled Turtles are one of the few species known to prey on Cane Toads without being harmed by their toxins. Their ability to tolerate brackish water allows them to inhabit areas where other freshwater turtles cannot survive. They are highly adaptable and can remain submerged for extended periods using cloacal respiration, extracting oxygen from the water.