Cathaymyrus is a genus of Early Cambrian chordate known from the Chengjiang biota in Yunnan Province, China.

[4] Both species have a long segmented body with no distinctive head.

The segments resemble the v-shaped muscle blocks found in cephalochordates such as Amphioxus.

A long linear impression runs along the "back" of the body looking something like a chordate notochord.

[citation needed] While some authors have suggested that the genus is a cephalochordate and closely related to living lancelets, other authors have disputed this due to the poor preservation of the head region, considering its placement within Chordata uncertain.