| Ptychagnostus Temporal range:
| |
|---|---|
| |
| Ptychagnostus germanus | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | †Trilobita (?) |
| Order: | †Agnostida |
| Family: | †Ptychagnostidae |
| Genus: | †Ptychagnostus Jaekel, 1909 |
| Synonyms[1] | |
| |
Ptychagnostus is a member of the agnostida that lived during the Cambrian period. Ptychagnostidae generally do not exceed one centimetre in length.[1] Their remains are rarely found in empty tubes of the polychaete worm Selkirkia.[2] The genus probably ranged throughout the water column. It has two glabellar lobes, and three pygidial lobes.[3]
- ^ a b Samuel M. Gon III. "Agnostida Fact Sheet". A Guide to the Orders of Trilobites. Retrieved 18 November 2012.
- ^ Brian D. E. Chatterton, Desmond H. Collins & Rolf Ludvigsen (2003). "Cryptic behaviour in trilobites: Cambrian and Silurian examples from Canada, and other related occurrences". In Philip D. Lane, Derek J. Siveter & Richard A. Fortey (ed.). Trilobites and their Relatives: contributions from the third international conference, Oxford 2001. Special Papers in Palaeontology. Vol. 70. pp. 157–173. ISBN 978-0-901702-81-4.
- ^ Coppold, Murray and Wayne Powell (2006). A Geoscience Guide to the Burgess Shale, p.56. The Burgess Shale Geoscience Foundation, Field, British Columbia. ISBN 0-9780132-0-4.
© MMXXIII Rich X Search. We shall prevail. All rights reserved. Rich X Search