Common Centarury, European Centaury: Centaurium erythraea (Synonym: Centaurium umbellatum) - Basal leaves several, often in a rosette, each 15- 40 mm long. Leaves usually 2-veined from the base. Flowers numerous in compact clusters, commonly with 5 corolla lobes, the corollas often pink in color.
Great Basin Centaury, Western Centaury: Zeltnera exaltata (Synonym: Centaurium exaltatum) - Basal leaves few, well spaced, not forming a rosette, 5-40 mm long, each 1-veined from the base. Pedicel of central flower much greater than the flowers, usually longer than 2 cm. Calyx lobes 2-3 times longer than the tube. Flowers commonly with 4 corolla lobes (sometimes 5), the corollas often creamy in color.
Monterey Centaury, Muehlenberg's Centaury: Zeltnera muehlenbergii (Synonyms: Centaurium muehlenbergii, Centaurium muehlenbergii var. albiflorum) - Basal leaves few, well spaced, not forming a rosette, 5-40 mm long, each 1-veined from the base. Pedicels less than 2 cm, usually much less than the length of the flowers. Calyx lobes not much greater than the tube. Flowers commonly with 4 corolla lobes (sometimes 5), the corollas often creamy in color.
Slender Centaury: Centaurium tenuiflorum