Saw-shelled turtle

Saw-shelled turtle (Myuchelys latisternum)
Photo by Craig Latta
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Testudines
Family: Chelidae
Subfamily: Chelodininae
Genus: Myuchelys
Species: M. latisternum
Binomial name
Myuchelys latisternum
(Gray, 1867)[1]

The Saw-shelled turtle or Myuchelys latisternum, is a species of turtle in the Chelidae family. It is endemic to Australia, ranging along rivers and streams and connected swamps and lagoons from coastal Cape York Peninsula to northern New South Wales. They are thought to have been introduced to Lake Eacham in the Atherton Tablelands. Other common English names are: Serrated snapping turtle, or Common sawshell turtle.[2][3]

Contents

Description

The female is considerably larger than the male with a carapace up to 28 cm long compared to the males which rarely get bigger than about 18 cm. The carapace is roughly oval and broad at the rear.[2][3] They are not usually aggressive, but can bite fiercely. They can also emit a strong smell.[3]

The shell has marginal serrations which are the reason for its common name, the "Saw-shelled turtle". It retains some of these serrations throughout its life. "The head shield extends down the side of the head to just above the tympanum, and the top of the neck has prominent pointed tubercules (many of these with an apical sensory pit)."[3]

The carapace is mainly brown to dark brown, commonly with some dark blotches. The plastron (underside) is yellowish. The head is large with a projecting snout and a horny plate on the top. The neck can fold sideways. The feet are webbed and also clawed. Hatchlings have serrated hind legs which become smooth as they mature.[4]

Nomenclatural History

Myuchelys latisternum (Gray, 1867) (Common sawshell turtle)

follows that of Gray (1872a) and Boulenger (1889).[5]

The combination Wollumbinia latisternum (Gray, 1867) Wells, 2007, was declared unpublished and hence unavailable for use by Georges & Thomson, 2010.[7]

Nesting

The females nest from September to December. They can have three to four clutches in one season of between 9 and 36 eggs which hatch before winter in about 60 days, with the incubation period shortened in southern regions.[3] The eggs are variably described as either, "hard-shelled (34 X 22 mm)",[2] or as small and "flexible-shelled".[3]

Feeding habits

The Saw-shelled turtle is carnivorous and feeds on fish, tadpoles, frogs, aquatic insects and is one of the few native Australian animals successful in preying on the introduced and very poisonous Cane Toads (Bufo marinus).[2] Toads too large to swallow whole are first shredded with their front claws.[3]

References

  1. ^ a b Gray, J.E. 1867. Description of a new Australian tortoise. Annals and Magazine of Natural History. 3(20):43-45
  2. ^ a b c d Ryan, Michelle, General Editor. (2000). Wildlife of Tropical North Queensland: Cooktown to Mackay. Queensland Museum. ISBN 0-7242-9349-3.
  3. ^ a b c d e f g Ehmann, Harold (1992). Encyclopedia of Australian Animals: Reptiles. Angus&Robertson. ISBN 0 207 17379 6 (Reptiles)
  4. ^ Elseya latisternum
  5. ^ Gray, J.E. 1871. On Euchelymys a new genus and two new species of Australian freshwater tortoises. Annals and Magazine of Natural History. (4)8:117-118.
  6. ^ Thomson, S. & 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.
  7. ^ Georges, A. & Thomson, S. 2010. Diversity of Australasian freshwater turtles, with an annotated synonymy and keys to species. Zootaxa 2496: 1–37.

External links