Beaked whales are the members of the family Ziphiidae, which consists of 22 species. These toothed whales are notable for their elongated beaks. Among air-breathing animals, beaked whales are some of the most extreme divers: Cuvier's beaked whales regularly dive for an hour at a depth over , and the longest and deepest foraging dive recorded is 137.5 minutes and . This is the greatest dive-depth known for a mammal.