''Chelodina'', collectively known as snake-necked turtles, is a large and diverse genus of long-necked
chelid
Chelidae is one of three living families of the turtle suborder Pleurodira, and are commonly called Austro-South American side-neck turtles. The family is distributed in Australia, New Guinea, parts of Indonesia, and throughout most of South Amer ...
turtles with a complicated
nomenclatural
Nomenclature (, ) is a system of names or terms, or the rules for forming these terms in a particular field of arts or sciences. The principles of naming vary from the relatively informal conventions of everyday speech to the internationally agree ...
history.
Although in the past, ''Macrochelodina'' and ''Macrodiremys'' have been considered separate genera and prior to that all the same, they are now considered subgenera of the ''Chelodina'',
further ''Macrochelodina'' and ''Macrodiremys'' are now known to apply to the same species, hence ''Chelydera'' is used for the northern snake-necked turtles.
''Chelodina'' is an ancient group of
chelid
Chelidae is one of three living families of the turtle suborder Pleurodira, and are commonly called Austro-South American side-neck turtles. The family is distributed in Australia, New Guinea, parts of Indonesia, and throughout most of South Amer ...
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 ...
s native to
Australia,
New Guinea
New Guinea (; Hiri Motu: ''Niu Gini''; id, Papua, or , historically ) is the world's second-largest island with an area of . Located in Oceania in the southwestern Pacific Ocean, the island is separated from Australia by the wide Torr ...
, the Indonesian
Rote Island
Rote Island ( id, Pulau Rote, also spelled ''Roti'') is an island of Indonesia, part of the East Nusa Tenggara province of the Lesser Sunda Islands. According to legend, this island got its name accidentally when a lost Portuguese sailor arriv ...
, and
East Timor
East Timor (), also known as Timor-Leste (), officially the Democratic Republic of Timor-Leste, is an island country in Southeast Asia. It comprises the eastern half of the island of Timor, the exclave of Oecusse on the island's north-we ...
. The turtles within this subgenus are small to medium-sized with oval shaped
carapace
A carapace is a 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 tortoises, the und ...
. They are side-necked turtles, meaning they tuck their head partially around the side of their body when threatened instead of directly backwards.
''Chelydera'' represents those species that have often been termed the ''Chelodina'' B group or thick necked snake neck turtles. The subgenus was described in 2020 by Thomson & Georges (in Shea et al. 2020). They are a side-neck turtle of the family Chelidae with extremely long necks and long flattened heads. They are specialist fish eaters using a strike and gape mode of feeding. They are medium to large species with the largest ''Chelodina (Chelydera) expansa'' reaching shell lengths of some .
Macrochelodina expansa (Grey, 1856) - Broad-Shelled Turtle
The first fossils (''C. (Chelydera) alanrixi'') are known from 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
, established_ ...
from the Eocene
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...
period (Lapparent de Broin, F. de, & Molnar, R. E., 2001).
''Macrochelodina'' (Wells & Wellington, 1985) is a monotypic subgenus of the ''Chelodina''. Its sole member is the enigmatic ''Chelodina'' (''Macrochelodina'') ''oblonga'' from Western Australia
Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to ...
.
Taxonomy
Current taxonomy follows that of Georges & Thomson, 2010 with updates from van Dijk et al. 2014 and Shea et al. 2020.
Synonymous names for the ''Chelodina'' Fitzinger 1826 genus include: ''Hydraspis'' Bell 1828, ''Chelyodina'' Agassiz 1846:79 (nomen novum
In biological nomenclature, a ''nomen novum'' (Latin for "new name"), new replacement name (or replacement name, new substitute name, substitute name) is a scientific name that is created specifically to replace another scientific name, but only w ...
), ''Hesperochelodina'' Wells and Wellington 1985 (nomen nudum
In taxonomy, a ''nomen nudum'' ('naked name'; plural ''nomina nuda'') is a designation which looks exactly like a scientific name of an organism, and may have originally been intended to be one, but it has not been published with an adequate des ...
).
The type species for the ''Chelodina'' subgenus is ''Chelodina longicollis
The eastern long-necked turtle (''Chelodina longicollis'')Kennett, R., Roe, J., Hodges, K., and Georges, A. 2009. ''Chelodina longicollis'' (Shaw 1784) – eastern long-necked turtle, common long-necked turtle, common snake-necked turtle. ''In'': ...
'' (Shaw, 1794). The type species for the ''Chelydera'' subgenus is ''Chelodina parkeri
Parker's snake-necked turtle (''Chelodina parkeri'') is a species of turtle in the family Chelidae.
Taxonomy and etymology
The specific name ''parkeri'', is in honor of Australian naturalist Fred Parker Frederick or Fred Parker may refer to: ...
'' Rhodin and Mittermeier 1976. The type species for ''Macrochelodina'' is '' Chelodina oblonga'' Gray 1841.
List of species
Extinct species
There are three identified extinct species of Chelodina:
*'' Chelodina alanrixi'' de Broin and Molnar, 2001 is a species of snake-necked fossil turtle which was described in 2001 using material gathered in Redbank Plains, 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
, established_ ...
, Australia. It is a member of the Chelidae
Chelidae is one of three living families of the turtle suborder Pleurodira, and are commonly called Austro-South American side-neck turtles. The family is distributed in Australia, New Guinea, parts of Indonesia, and throughout most of South Ame ...
Pleurodira
The Pleurodira are one of the two living suborders of turtles, the other being the Cryptodira. The division between these two suborders represents a very deep evolutionary divide between two very different types of turtles. The physical differe ...
. The fossil has been dated to the Eocene Epoch
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "daw ...
.
*''Chelodina insculpta
''Chelodina insculpta'' is an extinct species of snake-necked turtle
Chelidae is one of three living families of the turtle suborder Pleurodira, and are commonly called Austro-South American side-neck turtles. The family is distributed in Aus ...
'' de Vis, 1897[de Vis, C.W. (1897). The extinct freshwater turtles of Queensland. ''Annals of the Queensland Museum'' 3: 3-7.] is an extinct species
In biology, a species is the basic unit of Taxonomy (biology), 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 ...
of snake-necked turtle
Chelidae is one of three living families of the turtle suborder Pleurodira, and are commonly called Austro-South American side-neck turtles. The family is distributed in Australia, New Guinea, parts of Indonesia, and throughout most of South Ame ...
that was described in 1897 from material gathered in Darling Downs, Queensland, Australia, restricted.[Thomson, S. A. 2000. A Revision of the Fossil Chelid Turtles (Pleurodira) Described by C.W. De Vis, 1897. ''Memoirs of the Queensland Museum'' 45(2):593-598.] It is a member of the Chelidae; Pleurodira. The fossil has been dated as Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58[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 ...](_blank)
.
*''Chelodina murrayi
''Chelodina murrayi'' is an extinct species of snake-necked turtle from the Waite Formation on the Alcoota Scientific Reserve, north-east of Alice Springs in the Northern Territory of Australia. The species would appear to belong to the ''Chel ...
'' Yates, 2013 is an extinct species of snake-necked turtle
Chelidae is one of three living families of the turtle suborder Pleurodira, and are commonly called Austro-South American side-neck turtles. The family is distributed in Australia, New Guinea, parts of Indonesia, and throughout most of South Ame ...
from the Waite Formation on the Alcoota Scientific Reserve, north-east of Alice Springs
Alice Springs ( aer, Mparntwe) is the third-largest town in the Northern Territory of Australia. Known as Stuart until 31 August 1933, the name Alice Springs was given by surveyor William Whitfield Mills after Alice, Lady Todd (''née'' Al ...
in the Northern Territory of Australia. The species would appear to belong to the ''Chelodina novaeguineae
The New Guinea snake-necked turtle (''Chelodina novaeguineae'') is a species of turtle in the family Chelidae. The species is found almost exclusively within Western Province, Papua New Guinea. Turtle Taxonomy Working Group hodin, A.G.J., Ivers ...
'' group of species within the subgenus ''Chelodina''.
Notes
References
External links
Overview of the genus ''Chelodina'' with original literature
{{Taxonbar , from=Q532358
Turtles of Australia
Turtle genera
Taxa named by Leopold Fitzinger