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Inioidea
River dolphins are a polyphyletic group of fully aquatic mammals that reside exclusively in freshwater or brackish water. They are an informal grouping of dolphins, which itself is a paraphyletic group within the infraorder Cetacea. Extant river dolphins are placed in two superfamilies, Platanistoidea and Inioidea. They comprise the families Platanistidae (the South Asian dolphins), the possibly extinct Lipotidae (Yangtze River dolphin), Iniidae (the Amazonian dolphins) and Pontoporiidae. There are five extant species of river dolphins. River dolphins, alongside other cetaceans, belong to the clade Artiodactyla, with even-toed ungulates, and their closest living relatives the hippopotamuses, from which they diverged about 40 million years ago. Specific types of dolphins can be pink. River dolphins are relatively small compared to other dolphins, having evolved to survive in warm, shallow water and strong river currents. They range in size from the long South Asian river dolp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetacea
Cetacea (; , ) is an infraorder of aquatic mammals belonging to the order Artiodactyla that includes whales, dolphins and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel themselves through the water with powerful up-and-down movements of their tail, which ends in a paddle-like fluke, using their flipper-shaped forelimbs to steer. While the majority of cetaceans live in marine environments, a small number reside solely in brackish water, brackish or fresh water. Having a cosmopolitan distribution, they can be found in some rivers and all of Earth's oceans, and many species migrate throughout vast ranges with the changing of the seasons. Cetaceans are famous for cetacean intelligence, their high intelligence, complex social behaviour, and the enormous size of some of the group's members. For example, the blue whale reaches a maximum confirmed length of and a weight of 173 tonne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pontoporiidae
Pontoporiidae is a family of toothed whales, containing the extant genus '' Pontoporia'', and ten extinct genera. ''Pontoporia'' contains the sole extant species, the La Plata dolphin, which is endemic to South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o .... References {{Taxonbar, from=Q13410384 Mammal families Taxa named by John Edward Gray Inioidea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amazon River Dolphin
The Amazon river dolphin (''Inia geoffrensis''), also known as the boto, bufeo or pink river dolphin, is a species of toothed whale Endemism, endemic to South America and is classified in the family Iniidae. Three subspecies are currently recognized: ''I. g. geoffrensis'' (Amazon river dolphin), ''I. g. boliviensis'' (Bolivian river dolphin) and ''I. g. humboldtiana'' (Orinoco river dolphin). The position of the Araguaian river dolphin (''I. araguaiaensis'') within the clade is still unclear. The three subspecies are distributed in the Amazon basin, the upper Madeira River in Bolivia, and the Orinoco basin, respectively. The Amazon river dolphin is the largest species of river dolphin, with many adult males reaching in weight, and in length. Adults acquire a pink color, more prominent, in males, giving it its nickname "pink river dolphin". Sexual dimorphism is very evident, with males measuring 16% longer and weighing 55% more than females. Like other toothed whales, they have a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odontoceti
The toothed whales (also called odontocetes, systematic name Odontoceti) are a parvorder of cetaceans that includes dolphins, porpoises, and all other whales with teeth, such as beaked whales and the sperm whales. 73 species of toothed whales are described. They are one of two living groups of cetaceans, the other being the baleen whales (Mysticeti), which have baleen instead of teeth. The two groups are thought to have diverged around 34 million years ago (mya). Toothed whales range in size from the and vaquita to the and sperm whale. Several species of odontocetes exhibit sexual dimorphism, in that there are size or other morphological differences between females and males. They have streamlined bodies and two limbs that are modified into flippers. Some can travel at up to 30 knots. Odontocetes have conical teeth designed for catching fish or squid. They have well-developed hearing that is well adapted for both air and water, so much so that some can survive even if they a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iniidae
Iniidae is a family of river dolphins containing one living genus, '' Inia'', and four extinct genera. The extant genus inhabits the river basins of South America, but the family formerly had a wider presence across the Atlantic Ocean. Iniidae are highly morphologically different from marine dolphins by way of adaptations suited to their freshwater riverine habitat. They also display a high amount of sexual dimorphism in the form of color and size. Seasonal movement between flooded plains and rivers is common, due to the variation of seasonal rain. There has been little research done on the family, in particular the species aside from the Amazon river dolphin. Evolution The South American river basins were flooded by marine waters, creating a new brackish habitat that allowed marine mammals to move into them. During the Miocene era, the sea level began to recede, trapping the mammals within the continent. Morphology Their necks are flexible, since their cervical vertebra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ganges River Dolphin
The Ganges river dolphin (''Platanista gangetica'') is a species of freshwater dolphin classified in the family Platanistidae. It lives in the Ganges and related rivers of South Asia, namely in the countries of India, Nepal, and Bangladesh. It is related to the much smaller Indus river dolphin which lives in the rivers of the Indus Basin in Pakistan and northwestern India. It is also known by the name susu (popular name) also shihu () in Assam and shushuk () in West Bengal and Bangladesh., page 451 etter Aand page 568 etter S The Ganges river dolphin has been recognized by the Government of India as its National Aquatic Animal and is the official animal of the Indian city of Guwahati. Its first occurrence, within the Hooghly River, was documented by William Roxburgh. Description The Ganges river dolphin has a rectangular, ridgelike dorsal fin and females tend to be larger than males. Ganges river dolphins usually are tan, chocolate brown, dark grey or light blue. They ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platanista
South Asian river dolphins are toothed whales in the genus ''Platanista'', which inhabit the waterways of the Indian subcontinent. They were historically considered to be one species (''P. gangetica'') with the Ganges river dolphin and the Indus river dolphin being subspecies (''P. g. gangetica'' and ''P. g. minor'' respectively). Genetic and morphological evidence led to their being described as separate species in 2021. The Ganges and Indus river dolphins are estimated to have diverged 550,000 years ago. They are the only living members of the family Platanistidae and the superfamily Platanistoidea. Fossils of ancient relatives date to the late Oligocene. South Asian river dolphins are small but stocky cetaceans with long snouts or rostra, broad flippers, and small dorsal fins. They have several unusual features. Living in murky river waters, they have eyes that are tiny and lensless; the dolphins rely instead on echolocation for navigation. The skull has large crests o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arktocara NT Small
''Arktocara'' is an extinct genus of river dolphin from the Oligocene epoch of Alaska, containing one species, ''A. yakataga''. Having been discovered in 25-million-year-old strata near the 60th parallel north, it is perhaps the oldest-known crown toothed whale and the northmost river dolphin discovered. It was a member of the now-extinct family Allodelphinidae, along with the genera '' Allodelphis'', '' Goedertius'', '' Ninjadelphis'', and '' Zarhinocetus''. It measured approximately , comparable to its closest living relative, the South Asian river dolphin, which measures . However, the animal probably had an elongated beak and neck, so it may have been longer. The animal is known only from a partially preserved skull. Its ecology may have been similar to the modern-day Dall's porpoise, and it may have competed with contemporaneous delphinoids. Its remains were found in the Poul Creek Formation, which has also yielded several mollusk species. Taxonomy The type specimen, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indus River Dolphin
The Indus river dolphin (''Platanista minor'') is a species of freshwater dolphin in the family Platanistidae. It is endemic to the Indus River basin in Pakistan and Beas River in northwestern India. This dolphin was the first discovered side-swimming cetacean. It is patchily distributed in five small, sub-populations that are separated by irrigation barrages. From the 1970s until 1998, the Ganges River dolphin (''Platanista gangetica'') and the Indus dolphin were regarded as separate species; however, in 1998, their classification was changed from two separate species to subspecies of a single species. However, more recent studies support them being distinct species. It has been named as the national mammal of Pakistan and the state aquatic animal of Punjab, India. Taxonomy The Indus river dolphin was described in 1853 by Richard Owen under the name ''Platanista gangetica, var. minor'', based on a dolphin skull, which was smaller than skulls of the Ganges river dolphin. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baiji
The baiji (''Lipotes vexillifer'') is a probably extinct species of freshwater dolphin native to the Yangtze river system in China. It is thought to be the first dolphin species driven to extinction due to the impact of humans. This dolphin is listed as "critically endangered: possibly extinct" by the IUCN, has not been seen in 20 years, and several surveys of the Yangtze have failed to find it. The species is also called the Chinese river dolphin, Yangtze river dolphin, Yangtze dolphin, and whitefin dolphin. The genus name ''Lipotes'' means "left behind" and the species epithet ''vexillifer'' means "flag bearer". It is nicknamed the "Goddess of the Yangtze" and was regarded as the goddess of protection by local fishermen and boatmen. It is not to be confused with the Chinese white dolphin (''Sousa chinensis'') or the finless porpoise (''Neophocaena phocaenoides''). This is the only species in the genus ''Lipotes''. The baiji population declined drastically in decades as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Society For Marine Mammalogy
The Society for Marine Mammalogy was founded in 1981 and is the largest international association of marine mammal scientists in the world. Mission The mission of the Society for Marine Mammalogy (SMM) is to promote the global advancement of marine mammal science and contribute to its relevance and impact in education, conservation and management. Objectives * Evaluate and promote the educational, scientific and managerial advancement of marine mammal science. * Gather and disseminate to members of the Society, the public, and public and private institutions, scientific, technical and management information through publications and meetings. * Provide scientific information, as required, on matters related to the conservation and management of marine mammal resources. History The Biennial Conferences on the Biology of Marine Mammals predate the founding of the Society. The Biennial Conferences were a successor to Tom Poulter's "Annual Conference on Biological Sonar and Diving M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family (biology)
Family (, : ) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". The delineation of what constitutes a family—or whether a described family should be acknowledged—is established and decided upon by active taxonomists. There are not strict regulations for outlining or acknowledging a family, yet in the realm of plants, these classifications often rely on both the vegetative and reproductive characteristics of plant species. Taxonomists frequently hold varying perspectives on these descriptions, leading to a lack of widespread consensus within the scientific community ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
