Sousa sahulensis
| Sousa sahulensis | ||||||||||||
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Sousa sahulensis |
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| Scientific name | ||||||||||||
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| Jefferson & Rosenbaum , 2014 |
Sousa sahulensis ( Syn . : Sousa queenslandensis Gaskin, 1972, noun nudum ) is a dolphin species that was only recognized as an independent species in 2014. It was named after its area of distribution, the flat Sahul shelf between northern Australia and New Guinea . On the Australian coast, the distribution area extends from the western Australian Ningaloo Reef to the border between Queensland and New South Wales . Thereis a gapbetween the range of Sousa sahulensis and that of its closest relative, the Chinese white dolphin ( Sousa chinensis ), whichcorrespondsto the gap between the Wallace line and the Lydekker line . The holotype examinedfor the initial description was a 2.27 meter long, dead male found in 1985 on Saunders Beach, northeast Queensland.
features
The maximum length of the species is 2.70 meters, males are slightly larger than females. Sousa sahulensis is gray in color, dark on the back and lighter on the belly. The border between dark back and light abdominal color runs in an arc from the eyes to the urogenital region. Adult specimens often have irregular white or pink spots on their bodies, but large areas of dark color remain and the animals do not whiten completely, as can adult Chinese white dolphins. Young animals are darker than the adult ones. The fin in Sousa sahulensis is approximately triangular and lower than in the Chinese white dolphin. Their elongated base can reach 14 to 24% of the body length. Sousa sahulensis also differs in the number of teeth per half of the upper jaw (31 to 35 in Sousa sahulensis , 32 to 38 in Sousa chinensis , 33 to 39 in Sousa plumbea and 27 to 32 in Sousa teuszii ) and the vertebrae (50 in S. sahulensis) , 50 to 53 in S. chinensis , 49 to 51 in S. plumbea and 52 to 53 in S. teuszii ) from its relatives. The back hump typical of the genus is missing.
literature
- Thomas A. Jefferson and Howard C. Rosenbaum: Taxonomic revision of the humpback dolphins (Sousa spp.), And description of a new species from Australia. Marine Mammal Science, Volume 30, Issue 4, pages 1494–1541, October 2014, DOI: 10.1111 / mms.12152
