Rotadiscus fossil map
Where fossils of Rotadiscus have been found, shown on the Earth as it looked about 525 million years ago and on today’s map.
Dots are fossil collections recorded in the Paleobiology Database. The “then” view moves today’s fossil sites back to their positions 525 million years ago (the time slice nearest the median age of the fossils) using the Merdith et al. (2021) plate model; positions are approximate. Open on the timeline map →
| Group | Ediacaran & Cambrian life |
|---|---|
| Lived | 521–516 million years ago (Stage 3) |
| Periods | Cambrian |
| Family | Rotadiscidae |
| Named by | Sun and Hou 1987 |
| Fossil records | 1 occurrences at 1 locations (PBDB) |
| Found in | China |
| Rock formations | Yuanshan |
About Rotadiscus
Rotadiscus is a genus of discoidal animal known from the Cambrian Chengjiang biota and classified with the eldonioids.
As with other eldonioids, it was originally thought to have been pelagic, but is now thought to be benthic.
In addition to the type species R. grandis, two other Rotadiscus species have been proposed. The first is known only from one complete juvenile specimen and a few fragments, and was originally described as "Brzechowia sp." It remains without a formal species name, but has been transferred to Rotadiscus. The species initially described as R. guizhouensis has since been reassigned to the genus Pararotadiscus.
A 2023 cladistic analysis based on new fossils places Rotadiscus, along with other eldonioids, as stem-group ambulacrarians in the clade Cambroernida.
Text in “About” is quoted from the Wikipedia article Rotadiscus (revision 1345703873), licensed under CC BY-SA 4.0; introduction excerpted verbatim, formatting removed. Ages, family, authority and fossil records: Paleobiology Database, accessed 23 October 2026. Ages are those of the rock layers the fossils were found in. Wikidata: Q124439768.
