Cephalorhynchus
Encyclopedia
Cephalorhynchus is a genus
in the dolphin
family
Delphinidae. It consists of four species:
The species have similar physical features - they are small, generally playful, blunt-nosed dolphins - but they are found in distinct geographical locations.
A recent phylogenetic analysis by May-Collado & Agnarsson (2006) indicates that two species traditionally assigned to the genus Lagenorhynchus
, the Hourglass Dolphin
L. cruciger and Peale's Dolphin
L. australis are actually phylogenetically nested among the species of Cephalorhynchus, and they suggest that these two species should be transferred to the genus Cephalorhynchus. There is some acoustic and morphological support for this arrangement, at least with respect to Peale's Dolphin. According to Schevill & Watkins (1971), Peale's Dolphin and the Cephalorhynchus species are the only dolphins that do not whistle (no acoustic data are available for the Hourglass Dolphin). Peale's Dolphin also shares with several Cephalorhynchus species the possession of a distinct white "armpit" marking behind the pectoral fin.
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...
in the dolphin
Dolphin
Dolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in 17 genera. They vary in size from and , up to and . They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly eating...
family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Delphinidae. It consists of four species:
- Commerson's DolphinCommerson's DolphinCommerson's Dolphin is one of four dolphins in the Cephalorhynchus genus. The species has also the common names Skunk Dolphin, Piebald Dolphin and Panda Dolphin...
, Cephalorhyncus commersonii - Chilean DolphinChilean DolphinThe Chilean Dolphin , also known as the Black Dolphin, is one of four dolphins in the Cephalorhynchus genus. The dolphin is only found off the coast of Chile, it is commonly referred to in the country as Tunina....
, Cephalorhyncus eutropia - Heaviside's DolphinHeaviside's DolphinThe Haviside's Dolphin , or mistakenly the Heaviside's Dolphin, is a small dolphin that is found off the coast of Namibia and the west coast of South Africa...
, Cephalorhyncus heavisidii - Hector's DolphinHector's DolphinHector's dolphin is the best-known of the four dolphins in the genus Cephalorhynchus and is found only in New Zealand. At about 1.4 m in length, it is one of the smallest cetaceans....
, Cephalorhyncus hectori
The species have similar physical features - they are small, generally playful, blunt-nosed dolphins - but they are found in distinct geographical locations.
A recent phylogenetic analysis by May-Collado & Agnarsson (2006) indicates that two species traditionally assigned to the genus Lagenorhynchus
Lagenorhynchus
Lagenorhynchus is a genus in the order Cetacea, traditionally containing six species:* white-beaked dolphin, Lagenorhynchus albirostris* Atlantic white-sided dolphin, Lagenorhynchus acutus...
, the Hourglass Dolphin
Hourglass Dolphin
The hourglass dolphin is a small dolphin in the family Delphinidae that inhabits Antarctic and sub-Antarctic waters....
L. cruciger and Peale's Dolphin
Peale's Dolphin
Peale's Dolphin is a small dolphin found in the waters around Tierra del Fuego at the foot of South America. It is also commonly known as the Black-chinned Dolphin or even Peale's Black-chinned Dolphin...
L. australis are actually phylogenetically nested among the species of Cephalorhynchus, and they suggest that these two species should be transferred to the genus Cephalorhynchus. There is some acoustic and morphological support for this arrangement, at least with respect to Peale's Dolphin. According to Schevill & Watkins (1971), Peale's Dolphin and the Cephalorhynchus species are the only dolphins that do not whistle (no acoustic data are available for the Hourglass Dolphin). Peale's Dolphin also shares with several Cephalorhynchus species the possession of a distinct white "armpit" marking behind the pectoral fin.