PRIMITIVE FISH OF THE CHENGJIANG LAGERSTÄTTE

Three genera of Lower Cambrian fish are known from the 530 million-year-old Chengjiang Lagerstätte in Yuxi, Yunnan Province, southern China. The locality is just north of Fuxian Lake and about a half-hour drive south from the city of Kunming.

• Haikouichthys ercaicunensis
• Myllokunmingia fengjiaoa
• Zhongjianichthys rostratus

The first two of these are fusiform in shape, whereas the third is eel-like. Myllokunnmingial and Haikouichthys have fusiform bodies and pairs of large eyes within the dorso-anterior lobe. Zhongjianichthys has eyes behind the dorso-anterior lobe.

A friend of mine, Eldon Grupp from the USA, found an 18 mm specimen on a mortality slab of Haikouella from Chengjiang. Apparently, no one had noticed it before shipping. Not surprising as Zhongjianichthys are easy to overlook. I've asked him if I can get a photo of that mortality plate to share with you. It's quite stunning. Haikouella, of course, are not vertebrates, but advanced craniate chordates. The specimen in question, however, was a vertebrate. Eldon has assigned this specimen to genus Zhongjianichthys based on its eel-like characteristics and its large eyes located behind the anterior or rostral lobe instead of within it. Even so, family affiliation is uncertain.