''Stenella'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of marine mammals in

Delphinidae Oceanic dolphins or Delphinidae are a widely distributed family of dolphins that live in the sea. Close to forty extant species are recognised. They include several big species whose common names contain "whale" rather than "dolphin", such as the ...

, the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

informally known as the oceanic dolphins.

Species

Currently, five species are recognised in this genus: The common name for species in this genus is the "spotted dolphins" or the "bridled dolphins". They are found in temperate and tropical seas all around the world. Individuals of several species begin their lives spotless and become steadily more covered in darker spots as they get older. The genus name comes from the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

''stenos'' meaning narrow. It was coined by John Gray in 1866 when he intended it as a subgenus of '' Steno''. Modern taxonomists recognise two genera. The clymene dolphin (''S. clymene'') is the only confirmed case of hybrid speciation in marine mammals, descending from the spinner dolphin (''S. longirostris'') and the striped dolphin (''S. coeruleoalba''). Stenella dolphins tend to be more active during nighttime and spend their daytime resting. Although these dolphins are supposed to spend 60% of their daytime resting, they happen to be exposed to human activities for 80% of their day. These patterns of sleep deprivation can have negative impact on their resting habit and leads to decline in their population size.

References

Oceanic dolphins Cetacean genera Taxa named by John Edward Gray {{whale-stub