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Iniidae is a family of river dolphins containing one living and four extinct genera. The dentition of Iniidae dolphins is heterodont, having conical, small teeth. The teeth extend lingually in the back and in the front they have a small depression on the side of each. These mammals are carnivorous, finding prey by using echolocation. Breeding for Iniidae dolphins is seasonal, and varies according to food availability and water levels. A single offspring is produced per season. The gestation period is approximately 8.5 months, and they can produce offspring every year and a half. The lactation period is long, and calves stay with mothers for a few years before becoming dependent. The age of maturity is unknown, but thought to be at a few years old. Mating systems of this family are unknown, but scientists do know that females take after the young and look to be the limiting factor, which suggests a polygynous system. ==Taxonomy== The family was described by John Edward Gray in 1846.〔 Current classifications include a single living genera, ''Inia'', with one to three species and several subspecies. The family also includes three extinct genera described from fossils found in South America, Florida, Libya, and Italy.〔 *Superfamily Inioidea * *Family Iniidae * * *Genus †''Goniodelphis'' * * * * ''G. hudsoni'' * * *Genus ''Inia'' * * * * ''Inia araguaiaensis'' - Araguaian river dolphin * * * * ''Inia boliviensis'' - Bolivian river dolphin * * * * ''Inia geoffrensis'' - Amazon river dolphin * * * * * ''I. g. geoffrensis'' - Amazonian river dolphin * * * * * ''I. g. humboldtiana'' - Humboldt River dolphin * * *Genus †''Meherrinia'' * * *Genus †''Ischyrorhynchus'' (syn. ''Anisodelphis'') * * * * ''I. vanbenedeni'' (syn. ''Anisodelphis brevirostratus'') * * *Genus †''Saurocetes'' (syn. ''Saurodelphis'', ''Pontoplanodes'') * * * * ''S. argentinus'' (syn. ''Pontoplanodes obliquus'') * * * * ''S. gigas'' 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Iniidae」の詳細全文を読む スポンサード リンク
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