Hemisyntrachelus
| Hemisyntrachelus Temporal range: Miocene - Quaternary | |
|---|---|
 | |
| Hemisyntrachelus cortesii skull | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Synapsida |
| Class: | Mammalia |
| Order: | Artiodactyla |
| Infraorder: | Cetacea |
| Family: | Delphinidae |
| Subfamily: | Orcininae |
| Genus: | †Hemisyntrachelus Brandt, 1873 |
Hemisyntrachelus is an extinct genus of cetacean.[1][2][3]
Fossil records
This genus is known in the fossil records from the Miocene to the Quaternary (age range: from 5.332 to 1.806 million years ago). Fossils are found in the marine strata of Italy, the Netherlands, Chile and Peru.[2][3]
Species
The following species have thus far been classified as belonging to this genus:.[2][3]
- Hemisyntrachelus cortesii Fischer 1829
- Hemisyntrachelus oligodon Pilleri and Siber 1989
- Hemisyntrachelus pisanus Biannuci 1996
Description
Hemisyntrachelus cortesii lived about three million years ago (from 3.6 to 2.588 mya).[3] Its fossil skeleton reaches a length of about 3 meters and it has been found only in northern of Italy. This species shows intermediate characters between the bottlenose dolphin and the killer whale. It fed on large fishes and squids.
Hemisyntrachelus oligodon lived from 7.246 to 5.332 million years ago. Fossils have been found only in the Pisco Formation of Peru.[3]
Hemisyntrachelus pisanus could reach a length of about 5 metres (16 ft). It was widespread in the Mediterranea Sea during the Miocene. Fossils have been found only in Orciano, which is in a Piacenzian coastal claystone in Italy.
Gallery
Skull cast of Hemisyntrachelus cortesii
Skull cast of Hemisyntrachelus pisanus
References
- ↑ Bianucci, G.; Vaiani, S. C.; Casati, S. (2009). "A new delphinid record (Odontoceti, Cetacea) from the Early Pliocene of Tuscany (Central Italy): Systematics and biostratigraphic considerations". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 254 (3): 275. doi:10.1127/0077-7749/2009/0018.
- 1 2 3 Global Biodiversity Information Facility article on Hemisyntrachelus, accessed 11/10/13.
- 1 2 3 4 5 Plaeobiology Database