The females possess three black spots on their back to the rear of the dorsal fin, with white colouration between then which stretch to the tail[4] which are not present on males.

[2] The long dorsal fin is even in height along its length and this species has large scales which are bigger than the pupil of the eye.

They are oviparous and the female can lay up to a thousand eggs in a dish-shaped nest made by the male from algae, which he then guards.

[2] The cuckoo wrasse is a protogynous hermaphrodite, and females can change sex into males, a process which takes around seven months.

[1] The diet consists mainly of crustaceans but it will also take fishes, molluscs[1] and worms/[2] The name cuckoo wrasse comes from Cornish fishermen who associated the blue markings with bluebell flowers.

In the Cornish language, a bluebell is bleujenn an gog, literally "the cuckoo flower".