Walcottidiscus
| Walcottidiscus Temporal range: Burgess Shale | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Echinodermata |
| Subphylum: | Pelmatozoa |
| Class: | Edrioasteroidea |
| Genus: | Walcottidiscus Bassler, 1935 |
| species | |
| |
Walcottidiscus is a genus of pentagonally shaped echinoderms known from the Middle Cambrian Burgess Shale. 16 specimens of Walcottidiscus are known from the Greater Phyllopod bed, where they comprise < 0.1% of the community.[1]
The genus is thought to be the earliest known, more or less undisputed edrioasteroid. The pentamerous Arkarua is older, dating from the late Precambrian, but, no evidence of having stereoms throws its entire status as an edrioasteroid echinoderm into doubt.
There are two species recognized, each known from a single, poorly preserved fossil specimen. W. typicallis is known from the smaller specimen, and W. magister is known from the larger specimen. Many experts suggest that W. magister actually represents a large specimen of W. typicallis, but more, better preserved specimens are needed to verify this hypothesis.
External links
- "Walcottidiscus typicalis". Burgess Shale Fossil Gallery. Virtual Museum of Canada. 2011.
References
- ↑ Caron, J. -B.; Jackson, D. A. (October 2006). "Taphonomy of the Greater Phyllopod Bed community, Burgess Shale". PALAIOS 21 (5): 451–465. doi:10.2110/palo.2003.P05-070R.