Pseudodon Explained

Pseudodon is a genus of bivalvia of the Unionidae family that is native to East and Southeast Asia. There are 14 recognized species.

Description

The taxon was described by John Gould from his findings at the Salween River Basin in British Burma as a subgenus of the genus Anodon. Gould included two species in the taxon, the type species Anodon inoscularis and Anodon salweniana.^[1]

The shell of Pseudodon is rather thick and shaped like an elongated oval, with a slightly convex crown on the upper valve shifted toward the rear.^[2] The surface, although most often smooth, is in some species crossed by deep transverse furrows. The hinge teeth are high, thick, and rounded at the apices.^[3]

Range

The habitat of the genus is limited to East and Southeast Asia, mainly the Yangtze River Basin and Myanmar. The species Pseudodon inoscularis is also found in Thailand, Cambodia, and southern Vietnam, while the species Pseudodon resupinatus is endemic to northern Vietnam,^[4] and the species Pseudodon vondembuschianus is found in Indonesia and Indochina.^[5]

Hominid use

See main article: Pseudodon shell DUB1006-fL. thumb|Pseudodon shell DUB1006-fL, with details of the engraving.

Pseudodon shell DUB1006-fL is a fossil shell of Pseudodon vondembuschianus trinilensis that was found in Trinil, Java, Indonesia. The shell has a zigzag pattern engraved on it by a Homo erectus. It was carved between 540,000 and 430,000 years before present, and is the oldest known anthropogenic carving in the world.^[6] There is an ongoing controversy on whether or not the carving can qualify as art (which would make it the oldest piece of art in the world). Some commentators call it a "doodle"^[7] or "decorative marks",^[8] while others suggest that the carving is explicitly art.^{[9] [10] [11]}

Currently recognized species

• Pseudodon aureus
• Pseudodon avae
• Pseudodon bogani
• Pseudodon crebristriatus
• Pseudodon inoscularis
• Pseudodon kayinensis
• Pseudodon manueli
• Pseudodon nankingensis
• Pseudodon peguensis
• Pseudodon pinchonianus
• Pseudodon resupinatus
• Pseudodon salwenianus
• Pseudodon secundus
• Pseudodon vondembuschianus

Notes and References

1. December 6th, 1843. Proceedings of the Boston Society of Natural History. 1841. 160–161. Boston Society of Natural History. 1. Boston .
2. Bolotov. Ivan N.. Vikhrev. Ilya V.. Kondakov. Alexander V.. Konopleva. Ekaterina S.. Gofarov. Mikhail Yu. Aksenova. Olga V.. Tumpeesuwan. Sakboworn. 2017-09-14. New taxa of freshwater mussels (Unionidae) from a species-rich but overlooked evolutionary hotspot in Southeast Asia. Scientific Reports. en. 7. 1. 11573. 10.1038/s41598-017-11957-9. 28912555 . 5599626 . 2017NatSR...711573B . 2045-2322.
3. Book: Haas, Fritz . Superfamilia Unionacea . . 1969 . 9783111721569 . 128.
4. http://mussel-project.uwsp.edu/fmuotwaolcb/validgen_110.html The Freshwater Mussels (Unionoida) of the World (and other less consequential bivalves). Genus Pseudodon Gould, 1844: valid species
5. Zieritz A., & Lopes-Lima M. Handbook and National Red-List of the Freshwater Mussels of Malaysia — Kuala Lumpur: IUCN Species Survival Commission, 2018. — P. 19.
6. Joordens. Josephine C. A.. d’Errico. Francesco. Wesselingh. Frank P.. Munro. Stephen. de Vos. John. Wallinga. Jakob. Ankjærgaard. Christina. Reimann. Tony. Wijbrans. Jan R.. Kuiper. Klaudia F.. Mücher. Herman J.. 2015. Homo erectus at Trinil on Java used shells for tool production and engraving. Nature. en. 518. 7538. 228–231. 10.1038/nature13962. 25470048. 2015Natur.518..228J. 4461751. 1476-4687.
7. Callaway. Ewen. Homo erectus made world's oldest doodle 500,000 years ago. Nature News. 10.1038/nature.2014.16477. 2014-12-03. 164153158.
8. News: Thompson. Helen. Zigzags on a Shell From Java Are the Oldest Human Engravings. 2021-04-18. Smithsonian Magazine. en. 2014-12-03.
9. News: Brahic. Catherine. Shell 'art' made 300,000 years before humans evolved. 2021-04-18. New Scientist. en-US. 2014-12-03.
10. News: Geggel. Laura 03. 540,000-Year-Old Shell Carvings May Be Human Ancestor's Oldest Art. 2021-04-18. livescience.com. en. 2014-12-03.
11. News: Keim. Brandon. 2014-12-04. World's Oldest Art Identified in Half-Million-Year-Old Zigzag. https://web.archive.org/web/20210224101121/https://www.nationalgeographic.com/adventure/article/141203-mussel-shell-oldest-art. dead. February 24, 2021. 2021-04-18. Adventure. en.