Kingdom Animalia
Phylum Chordata
Class  ???
Order Myllokunmingiida
Family Myllokunmingiidae
Genus Haikouichthys
1st Species Haikouichthys ercaicunensis
Other attributes
Time Range 535-520 mya
Location China
Name Meaning Haikou fish
Physical Dimensions 2.5 centimeters long
Dietary Classification  ???

Haikouichthys is a myllokunmingiid myllokunmingiidan jawless fish from the Terrenuevian-Cambrian Series 2 of China. It was named in 1999 by Zhe-Xi Luo. It was one of the oldest fishes to exist, and by extension, one of the oldest vertebrates.


Haikouichthys was a simple chordate. It was a small fish with a narrow body, 6-9 gills on each side of the body, and a dorsal fin running down the majority of its body. Its body would have been covered in smooth skin.


Haikouichthys' diet remains unknown.


Not much is known about Haikouichthys.

In popular cultureEdit

Haikouichthys was featured in the 1st episode of the 2005 documentary Walking with Monsters, where it is shown attacking an injured Anomalocaris (of course, this behavior is speculative). As well as this, it had evolved into Cephalaspis over a course of 92.8 (or 106) million years.

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