[1][2] Keichousaurus is among the most common sauropterygian fossils recovered and are often found as nearly complete, articulated skeletons, making them popular among collectors.

[2] The holotype of K. hui, was discovered in the Falang Formation of Guizhou Province, China in 1957 by Hu Chengzhi and was named by Young (1958).

[1] The second species, K. yuananensis, was discovered in the Chialingchiang Formation of Hebei, China and was named by Young (1965) based on the holotype specimen IVPP V.2799, a partial skeleton.

The morphology of Keichousaurus is most like that of Dactylosaurus, showing long and narrow upper temporal openings that extends to the rear of the skull of which is not found in other pachypleurosaurids.

[5] Preserved foetal specimens of Keichousaurus hui within their mothers suggests that the species was viviparous and gave birth to live young.