Blackstonia perfoliata ( L.) Hudson subsp. perfoliata
Family: GENTIANACEAE
Genus: Blackstonia
Catalan common name: Centaura groga.
Spanish common name: Clora.
Province distribution: Alacant. Balearic Islands. Barcelona. Castelló. Girona. Lleida. Tarragona. València.
Distribution in the islands: Mallorca. Menorca. Ibiza. Cabrera.
General distribution (Phytogeography): Holoartica
IUCN Category: Least concern
Flowering time: JanFebMarAprMayJunJulAugSepOctNovDec
Life-forms: Terophyte.
Habitats: Cultivated fields, path and road sides, disturbed zones. Therophytic calicole fields. Therophytic communities, road sides.
Characteristics: An easily recognisable erect plant because of its whitish colour, stems and hairless leaves, and above all because of its triangular, paired leaves which are completely united at their base (perfoliate); it also has a small rosette of leaves at its base. The flowers are a goldish-yellow with an irregular number of petals (normally more than five). It can be mistaken, if we are not careful, with Centaurium maritimum, which has similar-looking and coloured flowers, but this species does not have united leaves and the flower has five petals.