Big-headed turtle
| Big-headed turtle | |
|---|---|
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| A big-headed turtle (Platysternon megacephalum) | |
Scientific classification 
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Order: | Testudines |
| Suborder: | Cryptodira |
| Superfamily: | Testudinoidea |
| Family: | Platysternidae Gray, 1869[3] |
| Genus: | Platysternon Gray, 1831[3] |
| Species: | P. megacephalum
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| Binomial name | |
| Platysternon megacephalum | |
| Synonyms[4] | |
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The big-headed turtle (Platysternon megacephalum) is a species of turtle in the family Platysternidae from Southeast Asia and southern China.[3]
Background
[edit]Previously considered a distinct family placed on occasion in "Kinosternoidea", it was later moved to the Emydidae. This, as well as the subfamily and the genus Platysternon, are monotypic.
The big-headed turtle is named after its unproportionally large head which leads to an inability to retreat into its shell. In order to protect itself it instead has an armored head and sharp beak.[5]
Distribution
[edit]The big-headed turtle is found in Cambodia, China, Laos, Myanmar, Thailand, and Vietnam.[1][3] It is commonly found in fast flowing streams and waterfalls in rocky areas. [1]
Behaviour
[edit]
The big-headed turtle is known to readily climb over obstacles in and around rivers and fast streams, using its tail as a prop to extend the reach of its strong claws. It also uses its beak to assist in climbing.[6] It has been reported to climb trees and bushes. These turtles generally move more during the night, and are not prone to moving long distances. They have a general daily range of 0-89.6m and males tend to move further than the females in this species.[7] They are not strong swimmers, and when swimming, this species occasionally arches its tail in the manner of a scorpion.[6] The big-headed turtle cannot pull its head in its shell. That being the case, it will not hesitate to use its powerful jaws to defend itself. Its diet consists of fish, snails and worms.[8] It also tends to eat fruits like the Machilus spp., as well as insects, crabs and mollusks.[9]
Diet
[edit]Originally assumed to be strictly carnivorous, this appears to be an opportunistic feeder with a significant shift towards omnivory or herbivory. Using fecal matter, big-headed turtles are found to consume fruits (Machilus and Turpinia arguta), terrestrial insect adults/larva and aquatic larva (Coleoptera, Homoptera, Hymenoptera, Isoptera, Lepidoptera, Mantodea, Orthoptera, Diptera, Ephemeroptera, Odonata and Tricoptera), mollusks (Sulcospira hainanensis), frogs, rodents, and freshwater crabs. Their eating behavior changes depending on the environmental conditions, but predominantly consume fruits. Seeds partially digested were found to have increased germination success after turtle excretion, possibly connecting their frugivore habits to environmental conditions.[10]
Exploitation
[edit]The big-headed turtle is found quite frequently in illegal wildlife trade.[5] It is readily consumed in Asia and is frequently a market item. Hunters capture them on lines with baited straight pins, so this species is rapidly disappearing in the wild.[11] The species is also threatened by its use in the pet trade.[1]
Subspecies
[edit]- P. m. megacephalum, China, 1831[3]
- P. m. peguense, Myanmar and Thailand, 1870[3]
- P. m. shiui, Cambodia, Laos and Vietnam, 1987[3]
In addition, two other subspecies, P. m. tristernalis (1984) and P. m. vogeli (1969), have been given, but may be invalid.[12]
References
[edit]- ^ a b c Fong, J.; Hoang, H.; Li, P.; McCormack, T.; Rao, D.-Q.; Timmins, R.J.; Wang, L.; van Dijk, P.P. (2021). "Platysternon megacephalum". IUCN Red List of Threatened Species. 2021: e.T17585A1423706. doi:10.2305/IUCN.UK.2021-2.RLTS.T17585A1423706.en. Retrieved 15 November 2021.
- ^ "Appendices | CITES". cites.org. Retrieved 2022-01-14.
- ^ a b c d e f g h Rhodin 2010, pp. 000.107
- ^ Fritz, Uwe; Peter Havaš (2007). "Checklist of Chelonians of the World". Vertebrate Zoology. 57 (2): 264–265. doi:10.3897/vz.57.e30895. ISSN 1864-5755.
- ^ a b "The Big-headed Turtle (Platysternon megacephalum) Project". asianturtleprogram.org. Retrieved 2023-04-20.
- ^ a b Kirkpatrick, David T. 1995. Platysternon megacephalum. Reptile & Amphibian Magazine, November/December 1995, pages 40 – 47. C/R. Archived May 22, 2011, at the Wayback Machine Retrieved 2012-11-25.
- ^ Shen, Jian-Wei; Pike, David A.; Du, Wei-Guo (2010). "Movements and Microhabitat Use of Translocated Big-Headed Turtles (Platysternon megacephalum) in Southern China". Chelonian Conservation and Biology. 9 (2): 154–161. doi:10.2744/CCB-0833.1. Retrieved 2023-02-10.
- ^ "Platysternon megacephalum (Big-headed Turtle)". Animal Diversity Web.
- ^ Sung, Yik-Hei; Hau, Billy; Karraker, Nancy (2016-01-01). "Diet of the endangered big-headed turtle Platysternon megacephalum". Natural Resources Science Faculty Publications. 4: e2784. doi:10.7717/peerj.2784. PMC 5157187. PMID 27994979.
- ^ Sung, Yik-Hei; Hau, Billy C.H.; Karraker, Nancy E. (2016-12-13). "Diet of the endangered big-headed turtle Platysternon megacephalum". PeerJ. 4: e2784. doi:10.7717/peerj.2784. ISSN 2167-8359. PMC 5157187. PMID 27994979.
- ^ James E. Barzyk Turtles in Crisis: The Asian Food Markets. The article itself is not dated, but mostly refers to data in the range 1995-2000.
- ^ Platysternon megacephalum Archived May 22, 2011, at the Wayback Machine
- Bibliography
- Rhodin, Anders G.J.; Paul van Dijk, Peter; Iverson, John B.; Shaffer, H. Bradley (2010-12-14). "Turtles of the World 2010 Update: Annotated Checklist of Taxonomy, Synonymy, Distribution and Conservation Status" (PDF). Archived from the original (PDF) on 2011-07-17. Retrieved 2010-12-15.
- Fritz, Uwe; Havaš, Peter (2007-10-31). "Checklist of Chelonians of the World" (PDF). Archived from the original (PDF) on 2011-05-01. Retrieved 2010-12-29.
- Pritchard, D. 1979. Encyclopedia of Turtles. New Jersey: T.F.H. Publications, Inc. Ltd.
- "The Big-headed Turtle (Platysternon megacephalum) Project". asianturtleprogram.org. Retrieved 2023-03-14
External links
[edit]
- Big-headed turtle (Platysternidae)
- (Chinese) Big-headed turtle
- (Spanish) Platysternon megacephalum Archived 2016-03-04 at the Wayback Machine