Haikouichthys
| Haikouichthys | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Live reconstruction |
||||||||||||
| Temporal occurrence | ||||||||||||
| Cambrian 2nd series, 3rd stage | ||||||||||||
| 520 to 516 million years | ||||||||||||
| Locations | ||||||||||||
|
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Haikouichthys | ||||||||||||
| Luo et al. , 1999 | ||||||||||||
Haikouichthys ( Gr .: "Fish from Haikou ") is a genus from the parent group of vertebrates (Vertebrata). The only species described is Haikouichtys ercaicunensis from the Lower Cambrian of China. In the Konservatlagerstätte of Chengjiang of the species have been recovered so far 500 individual fossils.
features
Haikouichtys were about 25 mm long, slender, fish-shaped and streamlined. The fossils reveal eyes, small paired nasal cavities and six gill arches in the first third of the body . In addition, a brain that is protected by cartilage substance. Up to ten square elements can be found on a notochord , which may be cartilaginous vertebrae. The heart, intestines and gonads can also be seen. V-shaped muscles can be seen in the back half of the body. The body ends with a rounded caudal fin.
Systematics
Because of the gills basket, an annular lip cartilage and a single, upwardly opening Nasenhypophysengangs it is believed that Haikouichthys the sister species of lamprey is (Petromyzontiformes) or the lamprey and the advanced vertebrates. Maybe Haikouichthys is identical to Myllokunmingia . In this case Haikouichthys would become the junior synonym of Myllokunmingia . D.-G. Shu of Northwest China University in Xi'an thinks this is unlikely.
literature
- Michael J. Benton : Paleontology of the vertebrates. 2007, ISBN 3-89937-072-4 .
- Joseph S. Nelson : Fishes of the World , John Wiley & Sons, 2006, ISBN 0-471-25031-7 .
- D.-G. Shu, H.-L. Luo, S. Conway Morris, X.-L. Zhang, S.-X. Hu, L. Chen, J. Han, M. Zhu, Y. Li & L.-Z. Chen: Lower Cambrian vertebrates from South China. Nature, 402, pp. 42-46, 1999 doi : 10.1038 / 46965
- D.-G Shu, S. Conway Morris, J. Han, Z.-F. Zhang, K. Yasui, P. Janvier, L. Chen, X.-L. Zhang, J.-N. Liu, Y. Li & H.-Q. Liu: Head and backbone of the Early Cambrian vertebrate Haikouichthys. Nature, 421, pp. 526-529, 2003 doi : 10.1038 / nature01264
Web links
- Haikouichthys at Palaeos.com (English)
- Haikouichthys at Paleobiology Database.org (English)
Individual evidence
- ↑ Wilfried Westheide & Reinhard Rieger : Special Zoology Part 2: Vertebrates and Skull Animals . 1st edition, Spektrum Akademischer Verlag, Heidelberg • Berlin 2004, page 192 ISBN 3-8274-0307-3
- ↑ D.-G. Shu, S. Conway Morris, Z.-F. Zhang and J. Han: The earliest history of the deuterostomes: the importance of the Chengjiang fossil deposit. Proceedings of the Royal Society B, 277, pp. 165-174, 2010, p. 172 doi : 10.1098 / rspb.2009.0646