Ptychagnostus atavus
| Ptychagnostus atavus Temporal range: Drumian | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | †Trilobita |
| Order: | †Agnostida |
| Family: | †Ptychagnostidae |
| Genus: | †Ptychagnostus |
| Species: | †P. atavus |
| Binomial name | |
| Ptychagnostus atavus (Tullberg, 1880) | |
| Synonyms | |
| |
Ptychagnostus atavus is a species of agnostid trilobite. It belongs to the genus Ptychagnostus in the family Ptychagnostidae. It was originally described by Swedish paleontologist Sven Axel Tullberg as Agnostus atavus in 1880.[1] It is used in biostratigraphy as an index fossil. Its first appearance at the GSSP section in the Wheeler Shale of Utah is defined as the beginning of the Drumian Age (around 504.5 million years ago) of the Cambrian Series 3 (Middle Cambrian).[2][3]
References
- ↑ "Ptychagnostus atavus". Paleobiology Database. Retrieved 16 November 2012.
- ↑ Babcock, L. E.; Robison, R. A.; Rees, M. N.; Peng, S.; Saltzman, M. R. (2007). "The Global boundary Stratotype Section and Point (GSSP) of the Drumian Stage (Cambrian) in the Drum Mountains, Utah, USA" (PDF). Episodes. 30 (2): 85–95.
- ↑ Ogg, G. "GSSP for Drumian Stage". Geologic TimeScale Foundation. Retrieved 16 November 2012.
This article is issued from Wikipedia - version of the 11/17/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.