''Pseudodon'' is a genus of

bivalvia Bivalvia () or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of aquatic animal, aquatic molluscs (marine and freshwater) that have laterally compressed soft bodies enclosed b ...

from the

Unionidae The Unionidae are a Family (biology), family of freshwater mussels, the largest in the order Unionida, the bivalve molluscs sometimes known as river mussels, or simply as unionids. The range of distribution for this family is world-wide. It is a ...

family of

freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mi ...

mussel Mussel () is the common name used for members of several families of bivalve molluscs, from saltwater and Freshwater bivalve, freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other ...

s native to

East East is one of the four cardinal directions or points of the compass. It is the opposite direction from west and is the direction from which the Sun rises on the Earth. Etymology As in other languages, the word is formed from the fact that ea ...

and

Southeast Asia Southeast Asia is the geographical United Nations geoscheme for Asia#South-eastern Asia, southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of the Mainland Au ...

. There are 12 recognized species. Their life cycle is thought to be akin to other Unionids, parasitizing fish in order to disperse. They are locally consumed and provide raw materials for

jewelry Jewellery (or jewelry in American English) consists of decorative items worn for personal adornment such as brooches, ring (jewellery), rings, necklaces, earrings, pendants, bracelets, and cufflinks. Jewellery may be attached to the body or the ...

cosmetics Cosmetics are substances that are intended for application to the body for cleansing, beautifying, promoting attractiveness, or altering appearance. They are mixtures of chemical compounds derived from either Natural product, natural source ...

, and

medicine Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...

Description

The taxon was described by

John Gould John Gould (; 14 September 1804 – 3 February 1881) was an English ornithologist who published monographs on birds, illustrated by plates produced by his wife, Elizabeth Gould (illustrator), Elizabeth Gould, and several other artists, includ ...

from his findings at the

Salween River The Salween is a Southeast Asian river, about long, flowing from the Tibetan Plateau south into the Andaman Sea. The Salween flows primarily within southwest China and eastern Myanmar, with a short section forming the border of Myanmar and Tha ...

Basin in

British Burma British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories and Crown Dependencies. * British national identity, the characteristics of British people and cultur ...

, initially described as a

subgenus In biology, a subgenus ( subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the ge ...

of '' Anodon''. Gould included two species in the taxon, the type species ''Anodon inoscularis'' and ''Anodon salweniana''. The

shell Shell may refer to: Architecture and design * Shell (structure), a thin structure ** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses Science Biology * Seashell, a hard outer layer of a marine ani ...

of ''Pseudodon'' is rather thick and shaped like an elongated oval, with a slightly convex crown on the upper valve shifted toward the rear. The surface, although most often smooth, is crossed by deep

transverse Transverse may refer to: *Transverse engine, an engine in which the crankshaft is oriented side-to-side relative to the wheels of the vehicle *Transverse flute, a flute that is held horizontally * Transverse force (or ''Euler force''), the tangen ...

furrows in some species. The

hinge teeth Hinge teeth are part of the anatomical structure of the inner surface of a bivalve shell, i.e. the shell of a bivalve mollusk. Bivalves by definition have two valves, which are joined together by a strong and flexible ligament situated on the hin ...

are high, thick, and rounded at the

apice Apice is a ''comune'' (municipality) in the Province of Benevento in the Italian region Campania, located about 70 km northeast of Naples and about 13 km east of Benevento. Apice borders the following municipalities: Ariano Irpino, Bon ...

Range

The distribution of the genus is limited to East and Southeast Asia, mainly the Yangtze River Basin and

Myanmar Myanmar, officially the Republic of the Union of Myanmar; and also referred to as Burma (the official English name until 1989), is a country in northwest Southeast Asia. It is the largest country by area in Mainland Southeast Asia and has ...

. The species '' Pseudodon inoscularis'' is also found in

Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...

Cambodia Cambodia, officially the Kingdom of Cambodia, is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. It is bordered by Thailand to the northwest, Laos to the north, and Vietnam to the east, and has a coastline ...

, and

southern Vietnam Southern Vietnam () is one of the three geographical regions of Vietnam, the other two being Northern and Central Vietnam. It includes 2 administrative subregions, which in turn are divided into 19 ''First Tier units'', of which 17 are provi ...

, while the species '' Pseudodon resupinatus'' is

endemic Endemism is the state of a species being found only 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 foun ...

to northern Vietnam, The Freshwater Mussels (Unionoida) of the World (and other less consequential bivalves). Genus ''Pseudodon'' Gould, 1844: valid species
''The Mussel Project, The University of Wisconsin-Stevens Point'' and the species '' Pseudodon vondembuschianus'' is found in

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

and

Indochina Mainland Southeast Asia (historically known as Indochina and the Indochinese Peninsula) is the continental portion of Southeast Asia. It lies east of the Indian subcontinent and south of Mainland China and is bordered by the Indian Ocean to th ...

Relation to humans

Pseudodon shell DUB1006-fL, with details of the engraving. Pseudodon shell DUB1006-fL is a

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 preserve ...

ized shell of ''Pseudodon vondembuschianus trinilensis'' that was found in

Trinil Trinil is a palaeoanthropological site on the banks of the Bengawan Solo in Ngawi Regency, East Java, Indonesia. It was at this site in 1891 that the Dutch anatomist Eugène Dubois discovered the first early hominin remains to be found outsid ...

Java Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...

. The shell has a

zigzag A zigzag is a pattern made up of small corners at variable angles, though constant within the zigzag, tracing a path between two parallel lines; it can be described as both jagged and fairly regular. In geometry, this pattern is described as a ...

pattern engraved on it by a ''

Homo erectus ''Homo erectus'' ( ) is an extinction, extinct species of Homo, archaic human from the Pleistocene, spanning nearly 2 million years. It is the first human species to evolve a humanlike body plan and human gait, gait, to early expansions of h ...

''. It was carved between 540,000 and 430,000 years before present, and is the oldest known anthropogenic carving in the world. There is an ongoing

controversy Controversy (, ) is a state of prolonged public dispute or debate, usually concerning a matter of conflicting opinion or point of view. The word was coined from the Latin '' controversia'', as a composite of ''controversus'' – "turned in an op ...

on whether or not the carving can qualify as

art Art is a diverse range of cultural activity centered around ''works'' utilizing creative or imaginative talents, which are expected to evoke a worthwhile experience, generally through an expression of emotional power, conceptual ideas, tec ...

(which would make it the oldest piece of art in the world). Some commentators call it a "

doodle A doodle is a drawing made while a person's attention is otherwise occupied. Doodles are simple drawings that can have concrete representational meaning or may just be composed of random and abstract art, abstract lines or shapes, generally w ...

" or "decorative marks", while others suggest that the carving is explicitly art.

Currently recognized species

WoRMS recognizes 12 species of ''Pseudodon''; * '' Pseudodon astensis'' (Sacco, 1886) * '' Pseudodon cambodjensis'' ( Petit de la Saussaye, 1865) * '' Pseudodon inoscularis'' (A. Gould, 1844) * '' Pseudodon lenyanensis'' (Bolotov et al., 2020) * '' Pseudodon mekongi'' (Bolotov et al., 2020) * '' Pseudodon nankingensis'' (Heude, 1874) * '' Pseudodon nicobaricus'' (Mörch, 1872) * '' Pseudodon pingi'' Otuka, 1942 * '' Pseudodon secundus'' Heude, 1877 * '' Pseudodon vagulus'' ( P. Fischer, 1891) * '' Pseudodon vondembuschianus'' (I. Lea, 1840) * '' Pseudodon walpolei'' (Hanley, 1871)

References

{{taxonbar, from=Q106915867 Unionidae Bivalve genera