Given the question: Information: - Iniidae is a family of river dolphins containing one living and four extinct genera. - Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. They are an informal grouping within the infraorder Cetacea, usually excluding dolphins and porpoises. Whales, dolphins and porpoises belong to the order Cetartiodactyla with even-toed ungulates and their closest living relatives are the hippopotamuses, having diverged about 40 million years ago. The two parvorders of whales, baleen whales (Mysticeti) and toothed whales (Odontoceti), are thought to have split apart around 34 million years ago. The whales comprise eight extant families: Balaenopteridae (the rorquals), Balaenidae (right whales), Cetotheriidae (the pygmy right whale), Eschrichtiidae (the gray whale), Monodontidae (belugas and narwhals), Physeteridae (the sperm whale), Kogiidae (the dwarf and pygmy sperm whale), and Ziphiidae (the beaked whales). - Brackish water or briny water is water that has more salinity than fresh water, but not as much as seawater. It may result from mixing of seawater with fresh water, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root "brak". Certain human activities can produce brackish water, in particular civil engineering projects such as dikes and the flooding of coastal marshland to produce brackish water pools for freshwater prawn farming. Brackish water is also the primary waste product of the salinity gradient power process. Because brackish water is hostile to the growth of most terrestrial plant species, without appropriate management it is damaging to the environment (see article on shrimp farms). - Porpoises are a group of fully aquatic marine mammals that are sometimes referred to as mereswine, all of which are classified under the family Phocoenidae, parvorder Odontoceti (toothed whales). There are six extant species of porpoise. They are small toothed whales that are very closely related to oceanic dolphins. The most obvious visible difference between the two groups is that porpoises have shorter beaks and flattened, spade-shaped teeth distinct from the conical teeth of dolphins. Porpoises, and other cetaceans, belong to the clade Cetartiodactyla with even-toed ungulates, and their closest living relatives are the hippopotamuses, having diverged from them about 40 million years ago. - The even-toed ungulates (order Artiodactyla) are ungulates (hoofed animals) whose weight is borne equally by the third and fourth toes. By contrast, odd-toed ungulates, such as horses, bear their weight primarily on their third toe. The aquatic Cetaceans (whales, dolphins, and porpoises) evolved from even-toed ungulate ancestors, and therefore modern taxonomic classification combines Artiodactyla and Cetacea into Cetartiodactyla. - Aquatic and semiaquatic mammals are a diverse group of mammals that dwell partly or entirely in bodies of water. They include the various marine mammals who dwell in oceans, as well as various freshwater species, such as the European otter. They are not a taxon and are not unified by any distinct biological grouping, but rather their dependence on and integral relation to aquatic ecosystems. The level of dependence on aquatic life are vastly different among species, with the Amazonian manatee and river dolphins being completely aquatic and fully dependent on aquatic ecosystems; whereas the Baikal seal feeds underwater but rests, molts, and breeds on land; and the capybara and hippopotamus are able to venture in and out of water in search of food. - Cetacea are a widely distributed and diverse clade of aquatic mammals that today consists of the whales, dolphins, and porpoises. Cetaceans are carnivorous and finned. Most species live in the sea, some in rivers. The name is derived from the Latin "cetus" "whale" and Greek "ketos" "huge fish". - India, officially the Republic of India ("Bhrat Gaarjya"), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country (with over 1.2 billion people), and the most populous democracy in the world. It is bounded by the Indian Ocean on the south, the Arabian Sea on the southwest, and the Bay of Bengal on the southeast. It shares land borders with Pakistan to the west; China, Nepal, and Bhutan to the northeast; and Myanmar (Burma) and Bangladesh to the east. In the Indian Ocean, India is in the vicinity of Sri Lanka and the Maldives. India's Andaman and Nicobar Islands share a maritime border with Thailand and Indonesia. Its capital is New Delhi; other metropolises include Mumbai, Kolkata, Chennai, Bangalore, Hyderabad and Ahmedabad. - Oceanic dolphins or Delphinidae are a widely distributed family of dolphins that live in the sea. Thirty extant species are described. They include several big species whose common names contain "whale" rather than "dolphin", such as the killer whale and the pilot whales. Delphinidae is a family within the superfamily Delphinoidea, which also includes the porpoises (Phocoenidae) and the Monodontidae (beluga whale and narwhal). River dolphins are relatives of the Delphinoidea. - River dolphins are a widely distributed group of fully aquatic mammals that reside exclusively in freshwater or brackish water . They are an informal grouping within the group dolphin , which is a paraphyletic group within the infraorder Cetacea . The river dolphins comprise the extant families Platanistidae ( the Indian dolphins ) , Iniidae ( the Amazonian dolphins ) , and Pontoporiidae ( the brackish dolphins ) . There are five extant species of dolphins , and two subspecies . River dolphins , alongside other cetaceans , belong to the clade Cetartiodactyla , with even - toed ungulates , and their closest living relatives the hippopotamuses , having diverged about 40 million years ago . River dolphins are relatively small compared to other dolphins , having evolved to survive in the warm and strong river currents . They range in size from the 5 - foot ( 1.5 m ) long South Asian river dolphin to the 8 - foot ( 2.4 m ) and 220 - pound ( 100 kg ) Amazon river dolphin . Several species exhibit sexual dimorphism , in that the males are larger than the females . They have streamlined bodies and two limbs that are modified into flippers . River dolphins use their conical - shaped teeth and long beaks to capture fast - moving prey in murky water . They have well - developed hearing that is adapted for both air and water ; they do not really rely on vision since the water they swim in is usually very muddy . These species are well - adapted to living in warm , shallow waters , and , unlike other cetaceans , have little to no blubber . River dolphins are not very widespread ; they are all restricted to certain rivers or deltas . This makes them extremely vulnerable to habitat destruction . River dolphins feed primarily on fish . Male river dolphins typically mate with multiple females every year , but females only mate every two to three years . Calves are typically born in the spring and summer months and females bear all the responsibility for raising them . River dolphins produce a variety of vocalizations ,... - Dolphins are a widely distributed and diverse group of aquatic mammals. They are an informal grouping within the order Cetacea, excluding whales and porpoises, so to zoologists the grouping is paraphyletic. The dolphins comprise the extant families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the new world river dolphins), and Pontoporiidae (the brackish dolphins), and the extinct Lipotidae (baiji or Chinese river dolphin). There are 40 extant species of dolphins. Dolphins, alongside other cetaceans, belong to the clade Cetartiodactyla with even-toed ungulates. Their closest living relatives are the hippopotamuses, having diverged about 40 million years ago. What is the relationship between 'river dolphin' and 'odontoceti'?
The answer is:
parent taxon