Steno

Steno is a monotypic genus of dolphin, family Delphinidae, containing the single species Steno bredanensis, the rough-toothed dolphin, found in deep warm and tropical waters worldwide and first described by Georges Cuvier in 1823. The genus name, Greek for narrow, refers to the animal's distinctively slender beak, while the species name honors the naturalist van Breda; the genus was formerly placed in its own subfamily but is now classified with the blunt-nosed dolphins in subfamily Globicephalinae. Its teeth have a roughened surface with numerous narrow irregular ridges, giving the species its common name.