Saw-shelled Turtle

Family: Cheliidae - Australoamerican Side-neck Turtles

Order: Testudines - Turtles

Class: Reptilia

Phylum: Chordata - Vertebrates

Kingdom: Animalia

Red List status: Not Listed

Myuchelys latisternum (Gray, 1867)
Saw-shelled turtle. South Johnstone, Wet Tropics World Heritage Area, Queensland

                               

Carapace length:  280 mm 

RANGE

The most widespread member of its genus, the saw-shelled turtle occurs along Australia's eastern seaboard, from the Jardine River in Cape York, Queensland south to the Richmond River in New South Wales. Isolated populations occur in the Northern Territory.

            Range            Description            Habitat            Behaviour            Biology            Taxonomy            References

Other common names: Serrated snapping turtle

 

DESCRIPTION

A moderately large turtle with an oval, strongly flattened carapace that broadens at the rear. The carapace is brown and is serrated along the rear edge, although this may not always be clear in adults. Skin colour is brown to black above and pale below, sometimes with a pale streak along the sides of the neck.The juvenile carapace possesses a strong central keel running down its length, and serrations are prominent. The short neck has numerous small spines. There is a large, horny shield across the top of the head, extending down the side of the head to the tympanum. The feet are webbed and the forefeet have five claws. The plastron is yellow in colour, and is narrow with the frontal portion being noticeably wider than the rear.

Similar species: The presence of a large head shield and spined tubercles on the neck distinguishes this species from most Australian

freshwater turtles. In addition, the central scute at the front of the plastron (the intergular) is as wide as the scutes to either side; in

other species it is as narrower. Differences in colouration and distribution also assist in distinguishing M. latisternum from related species. Uniquely, the edges of the head shield in this species extend down the sides of the head (see main photo).

Juvenile saw-shelled turtle. Note the central keel and serrated carapace.

 

HABITAT

This is a turtle of rivers, streams, lagoons and coastal regions, often in slow-flowing water. Populations may persist in large reservoirs created by damming.

 

BEHAVIOUR

Reproductive behaviour: Breeding takes place from September to January.

Diet: The saw-shelled turtle is omnivorous. Animal matter in the diet includes occasional introduced cane toads (Rhinella marina), and the turtle is among a small number of Australian species that appears to be able to consume toads at all life stages without ill effects.

 

BIOLOGY

Breeding Biology: Clutches number 9-17 eggs measuring 33 x 22 mm. Several clutches may be laid in a single breeding season, with eggs taking 60 days to hatch.

 

TAXONOMY

Until recently M. latisternum was included within the genus Elseya. Thomson and Georges (2009) elected to move this species to the new genus Myuchelys to reflect its closer affinity with turtles of the genus Emydura than with the remaining Elseya species. The new diagnosis also reflects a number of skeletal features not found in members of these other genera, as now defined.

 

REFERENCES

 

Wildlife of Tropical Queensland, The Queensland Museum 2000

Ernst, C.H., Altenburg, R.G.M. and Barbour, R.W. Elseya latisternum (Serrated Snapping Turtle). Turtles of the World

Thomson, S. amd Georges, A. (2009) Myuchelys gen. nov. a new genus for Elseya latisternum and related forms of Australian freshwater turtle (Testudines: Pleurodira: Chelidae) Zootaxa 2053: 32-42
Wilson, S. (2005) A Field Guide to Reptiles of Queensland, Reed New Holland
Wilson, S. and Swan, G. (2003) A Complete Guide to Reptiles of Australia, Reed New Holland