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Squalodontoidea (shark-toothed whales; order Cetacea, suborder Odontoceti) An extinct superfamily of toothed whales that comprises the family Squalodontidae and its immediate ancestors. The squalodonts were about the size of modern porpoises, which probably they resembled closely in appearance and behaviour. The teeth in the posterior part of the beak were triangular in shape and resembled those of sharks. The beak was often elongated. The skull was modified to the form characteristic of modern odontocetes and the blow-hole was positioned above and behind the eyes. The superfamily appeared in the late Oligocene and was distributed throughout the world during the early Miocene, but by the middle Miocene it was being replaced by more advanced porpoises and by the Pliocene the last squalodont was extinct.