The Gulf snapping turtle or Lavaracks' turtle (''Elseya lavarackorum'') is a large

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of freshwater

turtle Turtles are an order of reptiles known as Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked t ...

in the sidenecked family Chelidae.Georges A, Thomson S (2010)
"Diversity of Australasian freshwater turtles, with an annotated synonymy and keys to species".
''Zootaxa'' 2496: 1–37. The species is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to northern Australia in northwest

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , establishe ...

and northeast

Northern Territory The Northern Territory (commonly abbreviated as NT; formally the Northern Territory of Australia) is an Australian territory in the central and central northern regions of Australia. The Northern Territory shares its borders with Western Aust ...

. The species, similar to other members of the Australian snapping turtles in genus ''Elseya,'' only comes ashore to lay eggs and bask.Cann J (1998). ''Australian Freshwater Turtles''. Singapore: Beaumont. 292 pp. . The Gulf snapping turtle is a herbivore and primarily consumes '' Pandanus'' and figs.

Etymology

The specific name, ''lavarackorum'' (genitive plural), is in honor of Australian

paleontologists Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of foss ...

Jim Lavarack and Sue Lavarack who discovered the fossil remains of this species.Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. Baltimore: Johns Hopkins University Press. xiii + 296 pp. . (''Elseya lavarackorum'', p. 152).

Taxonomy

The species was first described in 1994 as ''Emydura lavarackorum'' after

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

material was found in Riversleigh in northwest Queensland. It was later demonstrated anatomically that because of its anterior bridge struts that it actually belonged to the genus ''

Elseya ''Elseya'' is a genus of large side-necked turtles, commonly known as Australian snapping turtles, in the family Chelidae. Species in the genus ''Elseya'' are found in river systems in northern and northeastern Australia and throughout the river ...

'' and further to a living, although undescribed form. The species was also declared at this time to be Australia's first

living fossil A living fossil is an extant taxon that cosmetically resembles related species known only from the fossil record. To be considered a living fossil, the fossil species must be old relative to the time of origin of the extant clade. Living foss ...

freshwater turtle and an extant population of a

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...

taxon In biology, a taxon ( back-formation from '' taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular n ...

. The latter gained significant public attention to this species after a story was published in Discover Magazine in January 1997.Zimmer C (1997)
"Shell Game"
''Discover Magazine'', January 1997 Issue. After placing this species in the correct genus, it was possible to look at the deeper phylogeny of the ''Elseya.'' This species lends its name to the group within the ''Elseya'' known as the Queensland ''Elseya'' or ''Elseya lavarackorum'' group.Thomson S, Georges A, Limpus C (2006). "A New Species of Freshwater Turtle in the Genus ''Elseya'' (Testudines: Chelidae) from Central Coastal Queensland, Australia". '' Chelon. Conserv. Biol.'' 5 (1): 74–86
PDF fulltext
This is a unique group of species that includes ''Elseya lavarackorum'' along with ''

Elseya albagula ''Elseya albagula'', commonly known as the white-throated snapping turtle, is one of the largest species of chelid turtles in the world, growing to about carapace length. The species is endemic to south-eastern Queensland, Australia, in the Bu ...

'' and '' Elseya irwini'', and all three are divergent from the ''Elseya dentata'' group.

Synonymy

*''Emydura lavarackorum'' **''Elseya lavarackorum'' **''Elseya lavarakorum'' **''Elseya lavackorum'' **''Elseya dentata lavarackorum'' **''Elseya'' (''Pelocomastes'') ''lavarackorum'' Thomson S, Amepou Y, Anamiato J, Georges A (2015). "A new species and subgenus of ''Elseya'' (Testudines: Pleurodira: Chelidae) from New Guinea". ''Zootaxa'' 4006 (1): 59-82
Preview (PDF)
/ref> **''Elseya'' (''Pelocomastes'') ''oneiros''

Description

The Gulf snapping turtle is a large, brown to dark brown, short-necked turtle. Its carapace, or upper shell, reaches in straight carapace length; it has an undulating suture between the hemeral and pectoral shields in the white plastron, or under shell. The undulating (rather than straight) suture in the plastron distinguishes it from the northern snapping turtle (''

Elseya dentata ''Elseya dentata'' (Gray, 1863),Gray, J.E. 1863. On the species of ''Chelymys'' from Australia, with the description of a new species. ''Annals and Magazine of Natural History''. 3(12):98-99 the northern snapping turtle, is a large aquatic turtle ...

'').Woinarski, John (compiler) (May 2006).

Geographic range and habitat

The Gulf snapping turtle is restricted to rivers draining into the Gulf of Carpentaria in the

and

. These rivers range from the

Nicholson Nicholson may refer to: People *Nicholson (name), a surname, and a list of people with the name Places Australia * Nicholson, Victoria * Nicholson, Queensland * Nicholson County, New South Wales * Nicholson River (disambiguation) * Nicholson ...

to Calvert River systems in the Northern Territory to the Gregory River in Queensland.

Behaviour

The Gulf snapping turtle is primarily

herbivorous A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpar ...

and eat fruits, flowers, leaves, bark and '' Pandanus'' roots, and the juveniles also eat

insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three ...

larvae.

Fig The fig is the edible fruit of ''Ficus carica'', a species of small tree in the flowering plant family Moraceae. Native to the Mediterranean and western Asia, it has been cultivated since ancient times and is now widely grown throughout the world ...

s are also an important food for the turtle. Despite its usually herbivorous diet, Lavaracks' turtle is readily trapped using meat as bait.

Reproduction

The eggs of ''E. lavarackorum'' are laid in soil near the edge of the water.

Status and conservation

The Gulf snapping turtle is listed as

Endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and in ...

under the Commonwealth ''Endangered Species Protection Act 1992'', as Vulnerable under Queensland's ''Nature Conservation Act 1992'', and as of

Least Concern A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...

under the Northern Territory's ''Territory Parks and Wildlife Conservation Act 2000''. The main threats to the turtle include disturbance to

nest A nest is a structure built for certain animals to hold eggs or young. Although nests are most closely associated with birds, members of all classes of vertebrates and some invertebrates construct nests. They may be composed of organic materi ...

ing sites by

feral A feral () animal or plant is one that lives in the wild but is descended from domesticated individuals. As with an introduced species, the introduction of feral animals or plants to non-native regions may disrupt ecosystems and has, in some ...

animals such as

pig The pig (''Sus domesticus''), often called swine, hog, or domestic pig when distinguishing from other members of the genus '' Sus'', is an omnivorous, domesticated, even-toed, hoofed mammal. It is variously considered a subspecies of ''Sus ...

habitat destruction Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

by grazing and watering

cattle Cattle (''Bos taurus'') are large, domesticated, cloven-hooved, herbivores. They are a prominent modern member of the subfamily Bovinae and the most widespread species of the genus ''Bos''. Adult females are referred to as cows and adult ma ...

, and potentially through changes to

hydrology Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and environmental watershed sustainability. A practitioner of hydrology is call ...

, disturbance, and

climate change In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to ...

. In addition to these main threats, Lavaracks' turtle has been known to get caught in fishing nets.