Haikouichthys fossil map
Where fossils of Haikouichthys 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 | Ancient fish & sharks |
|---|---|
| Lived | 521–516 million years ago (Stage 3) |
| Periods | Cambrian |
| Family | Myllokunmingiidae |
| Named by | Luo et al. 1999 |
| Fossil records | 2 occurrences at 1 locations (PBDB) |
| Found in | China |
| Rock formations | Yuanshan |
About Haikouichthys
Haikouichthys is an extinct genus of primitive jawless fish that lived during the Cambrian period, 518 million years ago, in what is now the Yunnan Province of China. Alongside Myllokunmingia and Zhongjianichthys, it is considered to be the earliest known vertebrate animal in the fossil record.
The type species, Haikouichthys ercaicunensis, was first described in 1999 in addition to its confamilial, Myllokunmingia, and more than 500 specimens were referred to this taxon as of 2003. The holotype was found in the Yuanshan member of the Qiongzhusi Formation in the 'Eoredlichia' Zone near Ercai Village in the Haikou Subdistrict (not to be confused with the city of Haikou in Hainan) of Xishan, Kunming, hence its specific name, which means "Haikou fish from Ercaicun". The fossil (along with Myllokunmingia's holotype) was recovered among the Chengjiang fauna, in one of a series of Lagerstätten sites where thousands of exquisitely preserved soft-bodied fossils have already been found.
Text in “About” is quoted from the Wikipedia article Haikouichthys (revision 1345651188), licensed under CC BY-SA 4.0; introduction excerpted verbatim, formatting removed. Ages, family, authority and fossil records: Paleobiology Database, accessed 22 October 2026. Ages are those of the rock layers the fossils were found in.
