Orcaella
Encyclopedia
The snubfin dolphins are a genus
of dolphins containing two members: the Irrawaddy Dolphin
and Australian Snubfin Dolphin
. The genus was long believed to be monotypic
with the only species being the Irrawaddy Dolphin; however, in 2005, genetic analysis showed that the Australian Snubfin Dolphin is closely related. Recent molecular analyses
indicate that the genus Orcaella is closely related to the Orca
of the genus Orcinus, the two of them together forming the subfamily Orcininae.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of dolphins containing two members: the Irrawaddy Dolphin
Irrawaddy dolphin
The Irrawaddy dolphin is a euryhaline species of oceanic dolphin found in discontinuous subpopulations near sea coasts and in estuaries and rivers in parts of the Bay of Bengal and Southeast Asia.-Etymology and taxonomic history:...
and Australian Snubfin Dolphin
Australian Snubfin Dolphin
The Australian snubfin dolphin is a dolphin found off the northern coasts of Australia. It closely resembles the Irrawaddy dolphin and was not described as a separate species until 2005. The Australian snubfin is tri-coloured, while the Irrawaddy dolphin only has two colours on its skin...
. The genus was long believed to be monotypic
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
with the only species being the Irrawaddy Dolphin; however, in 2005, genetic analysis showed that the Australian Snubfin Dolphin is closely related. Recent molecular analyses
Molecular phylogeny
Molecular phylogenetics is the analysis of hereditary molecular differences, mainly in DNA sequences, to gain information on an organism's evolutionary relationships. The result of a molecular phylogenetic analysis is expressed in a phylogenetic tree...
indicate that the genus Orcaella is closely related to the Orca
Orca
The killer whale , commonly referred to as the orca, and less commonly as the blackfish, is a toothed whale belonging to the oceanic dolphin family. Killer whales are found in all oceans, from the frigid Arctic and Antarctic regions to tropical seas...
of the genus Orcinus, the two of them together forming the subfamily Orcininae.