- Kingdom: Animalia
- Phylum: Chordata
- Subphylum: Vertebrata
- Superclass: Gnathostomata
- Class: Actinopterygii
- Order: Perciformes
- Family: Labridae
- Scientific name: Labrus mixtus
- Norwegian: blåstål/rødnebb
It can hardly be confused with any other species. The body is slim and the head elongated. The male may reach a length of 35 cm, females do not exceed 30. The female is red or orange with three dark spots interspersed with white ones along the dorsal fin. Young males have a similar coloration but sometimes lacks the dark spots. At the age of seven or more, some females change sex. In this process they develop a blue head and brilliant blue lines and spots along the body. Often the dominating female changes sex when the adult male in the shoal dies or disappears.
The cuckoo wrasse lives on rocky locations. During spring and summer it is often encountered among algae in the subtidal zone. In the winter it migrates down below 15 meters.
It is widespread in the Mediterranean and the east Atlantic Ocean, from Norway to Senegal.