The southern New Guinea giant softshell turtle (''Pelochelys bibroni'') is a

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 ...

softshell turtle The Trionychidae are a taxonomic family of a number of turtle genera, commonly known as softshell turtles. The family was erected by Leopold Fitzinger in 1826. Softshells include some of the world's largest freshwater turtles, though many can ad ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Trionychidae The Trionychidae are a taxonomic family of a number of turtle genera, commonly known as softshell turtles. The family was erected by Leopold Fitzinger in 1826. Softshells include some of the world's largest freshwater turtles, though many can a ...

. 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 elsew ...

to the lowlands of southern

New Guinea New Guinea (; Hiri Motu Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea). It is a simplified version of ...

with occasional

vagrant Vagrancy is the condition of homelessness without regular employment or income. Vagrants (also known as bums, vagabonds, rogues, tramps or drifters) usually live in poverty and support themselves by begging, scavenging, petty theft, temporar ...

individuals sighted off the coast of northern

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

.van Dijk PP">Rhodin AGJ, van Dijk PP
, Iverson JB, H. Bradley Shaffer, Shaffer HB (2010). "Turtles of the World, 2010 Update: Annotated Checklist of Taxonomy, Synonymy, Distribution, and Conservation Status"./ref> ''P. bibroni'' is referred to by the Suki people as ''kiya eise'', a reference to its flexible shell. In the

Arammba language Aramba (Arammba), also known as Serki or Serkisetavi, is a Papuan language of Papua New Guinea. It is spoken to the south of Western Province in the Trans Fly region. Aramba belongs to the Tonda Sub-Family, which is next to the Nambu Sub-Family r ...

, it is called ''sokrere'', meaning "earthquake". It is sometimes hunted by local villages for its meat and/or eggs, leading to some cases of chelonitoxism.

Habitat

''P. bibroni'' prefers lowland rivers and estuaries, but adjusts well to the saline environments of deltas and large estuaries.

Diet

The diet of ''P. bibroni'' is primarily

carnivorous A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other sof ...

, consuming mostly fish, crabs, mollusks, and occasionally some vegetation. Its hunting strategy is not overly aggressive, but primarily being an

ambush predator Ambush predators or sit-and-wait predators are carnivorous animals that capture or trap prey via stealth, luring or by (typically instinctive) strategies utilizing an element of surprise. Unlike pursuit predators, who chase to capture prey us ...

, it spends most of its time at the bottom of its chosen river bed, waiting for prey to wander by.

Reproduction

Nesting of ''P. bibroni'' usually occurs in September, often on the same beaches as the

pig-nosed turtle The pig-nosed turtle (''Carettochelys insculpta''), also known as the pitted-shelled turtle or Fly River turtle, is a species of turtle native to northern Australia and southern New Guinea. It is the only living member of the family Carettoche ...

(''Carettochelys insculpta''). The 22–45 eggs in a clutch are often found in the nests of crocodiles. This is possibly a strategy to avoid nest predation.Bonin, Franck; Devaux, Bernard; Dupré, Alain (2006). ''Turtles of the World''. (Translated by Peter C. H. Pritchard). Baltimore: Johns Hopkins University Press.

Etymology

The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

, ''bibroni'', is in honor of

French French (french: français(e), link=no) may refer to: * Something of, from, or related to France ** French language, which originated in France, and its various dialects and accents ** French people, a nation and ethnic group identified with Franc ...

herpetologist Herpetology (from Greek ἑρπετόν ''herpetón'', meaning "reptile" or "creeping animal") is the branch of zoology concerned with the study of amphibians (including frogs, toads, salamanders, newts, and caecilians (gymnophiona)) and rept ...

Gabriel Bibron Gabriel Bibron (20 October 1805 – 27 March 1848) was a French zoologist and herpetologist. He was born in Paris. The son of an employee of the Museum national d'histoire naturelle, he had a good foundation in natural history and was hir ...

Geographic range

''P. bibroni'' is

, where it is only found on the southern part of the island, south of the

Central Range Central Range, Central Mountains, or Central Mountain Range may refer to several ranges of mountains, including: * Central Range, New Guinea * Central Range, Taiwan * Central Range, Trinidad and Tobago * Central Range, Venezuela See also * Cent ...

. In the past, there was some confusion about its range limits, but it is now clear that the species found throughout much of South and

Southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical United Nations geoscheme for Asia#South-eastern Asia, south-eastern region of Asia, consistin ...

Cantor's giant softshell turtle The Asian giant softshell turtle (''Pelochelys cantorii''), also known commonly as Cantor's giant softshell turtle and the frog-faced softshell turtle, is a species of freshwater turtle in the family Trionychidae. The species is native to South ...

(''P. cantorii'' ) and that the species in northern New Guinea is the northern New Guinea giant softshell turtle (''P. signifera''). The ranges of the species do not overlap anywhere. Surprisingly enough, ''P. bibroni'' has some level of

salt tolerance Halotolerance is the adaptation of living organisms to conditions of high salinity. Halotolerant species tend to live in areas such as hypersaline lakes, coastal dunes, saline deserts, salt marshes, and inland salt seas and springs. Halophiles a ...

and is occasionally sighted in the offshore

marine environment Marine habitats are habitats that support marine life. Marine life depends in some way on the saltwater that is in the sea (the term ''marine'' comes from the Latin ''mare'', meaning sea or ocean). A habitat is an ecological or environmental ...

off southern New Guinea. Some individuals even manage to reach northern coastal

, with observers on the Australian coast occasionally sighting ''P. bibroni'' about once a decade (although no populations have yet been established). The lost

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

was even labeled as coming from Australia, although this is likely an error and it was most likely collected in New Guinea.

Description

''P. bibroni'' is the among the largest species of freshwater turtle, surpassed or matched only by other species of ''

Pelochelys ''Pelochelys'' is a genus of very large softshell turtles in the family Trionychidae. They are found from peninsular India northeast to southern China, and south to Southeast Asia and New Guinea. The species in this genus, while still being fre ...

'', as well as certain '' Chitra'', ''

Rafetus ''Rafetus'' is a genus of highly endangered softshell turtles in the family Trionychidae. It is a genus of large turtles which are found in freshwater habitats in Asia. Species According to most taxonomists, the genus ''Rafetus'' contains the fo ...

'', and ''

Macrochelys ''Macrochelys'' is a genus of very large freshwater turtles in the family Chelydridae from Southeastern United States. Only a single extant species was recognized until a 2014 study divided it into two, or possibly three species. Extant species ...

'' species. ''P. bibroni '' can reach up to in straight

carapace A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...

length, and in weight. It has a soft, subdermal carapace with a slightly flexible posterior region. Its neck is completely retractable, as are all four of its limbs. Its head is broad, with its nostrils at the end of a proboscis. Its digits are webbed, with eight digits on its fore limbs and five on its hind limbs. Its tail is very short.

Possible chelonitoxism

''P. bibroni'' is believed to be a species that, upon consumption by humans during certain seasons of the year, can lead to the phenomenon of chelonitoxism in a person. This may be due to certain phases in the turtle's diet.Silas, E. G.; Fernando, A. Bastian (1984). "Turtle poisoning". ''CMFRI Bulletin'' 35: 62–75.

Threatened status

''P. bibroni'' has a natural predator in the

saltwater crocodile The saltwater crocodile (''Crocodylus porosus'') is a crocodilian native to saltwater habitats and brackish wetlands from India's east coast across Southeast Asia and the Sundaic region to northern Australia and Micronesia. It has been listed ...

(''Crocodilus porosus''), but its current status as a threatened species stems from human activity. Locals often hunt the animal for its meat and eggs, and tribal masks can be crafted from its carapace. No commercial hunting is present, however. It is less threatened than its northern relative, '' P. signifera'', which has to also contend with introduced fish species and have led to a significantly degraded habitat.

References

External links

{{Taxonbar, from=Q2272259 Pelochelys Reptiles of Papua New Guinea Reptiles of Western New Guinea Reptiles described in 1853 Taxonomy articles created by Polbot Endemic fauna of New Guinea Turtles of Australia Turtles of New Guinea