Cuvier's beaked whale

The Cuvier's beaked whale, goose-beaked whale, or ziphius (Ziphius cavirostris) is the most widely distributed of all beaked whales in the family Ziphiidae. It is smaller than most baleen whales yet large among beaked whales. Cuvier's beaked whale is pelagic, inhabiting waters deeper than . It has the deepest and longest recorded dives among whales at and 222 minutes, though the frequency and reasons for these extraordinary dives are unclear. Despite its deep-water habitat, it is one of the most frequently spotted beaked whales. The species was named Ziphius cavirostris by Georges Cuvier, based on a skull fragment which he believed to be a fossil from an extinct species. He reused the genus name Ziphius from an undetermined species mentioned by historical sources. The species name cavirostris, from Latin cavus "hollow" and rostrum "beak", refers to a bony structure (cavity) anterior of the nares (the bones of the nose), now known as the prenarial basin. It is now known to be unique to males of this species. French naturalist and zoologist Georges Cuvier first described the species in Recherches sur les ossements fossiles ("Research on Fossil Bones", 1823) based on a skull collected on the Mediterranean coast of France at Fos-sur-mer, Bouches de Rhone in 1804. He named it Ziphius cavirostris from the Latin cavus for "hollow" or "concave", referring to the prenarial basin, a deep hollow in the skull which is now known to be found only in males of this species. Cuvier believed the skull represented the remains of an extinct species, and chose the genus name Ziphius to reflect an undetermined species mentioned by historical authors. Later, in 1850, paleontologist and zoologist Paul Gervais found the skull to be identical with that of a whale carcass more recently stranded on a beach. Cuvier's beaked whale is one of 22 species in the family Ziphiidae and the only member of the genus Ziphius. No other ziphiid develops the dense rostral ossification of the prenarial basin.