Herba de Santa Margalida – Centaurium bianoris (Sennen)
- Family: Gentianaceae.
- Genus: Centaurium.
- General distribution: Mediterranean.
- Flowering time: May to July.
- Habitat: Garrigue glades, roadsides.
- Vital forms: Therophyte.
- Status: Endemic.
An annual herb, with a small rosette of basal leaves and a well erect stem, which can branch out in the inflorescence. The leaves from the stem are opposite and oval.
The flowers have five salmon-coloured petals. The colour of the flowers immediately differentiates this species from the other Centaurium which live in the Balearics.
It is thought that it could be of hybrid origin between Centaurium maritimum (with yellow flowers) and Centaurium pulchellum which has red flowers, but there is no specific study to support the hypothesis.
It lives in the dry garrigues (Mediterranean woodland) of the islands; it flowers at the end of spring (June).