''Machaeranthera'' is a genus of North American flowering plants in the family

Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...

which are known by the common name tansyaster.Flora of North America Vol. 20 Page 394 ''Machaeranthera'' Nees, Gen. Sp. Aster. 13, 224. 1832.
/ref> Tansyasters are variable in appearance. Some are small, singular wildflowers, while others are sprawling shrubs. Several species easily hybridize with each other, as well, making identification difficult. In general, members of the genus may be identified by the sharp-pointed, dagger-shaped

anthers The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filamen ...

in the

disc florets Disc or disk may refer to: * Disk (mathematics), a two dimensional shape, the interior of a circle * Disk storage * Optical disc * Floppy disk Music * Disc (band), an American experimental music band * ''Disk'' (album), a 1995 EP by Moby Other ...

at the center of the flower. The flower heads are usually daisylike, and are usually a shade of purple or blue, but may be pink, yellow, or white. Tansyasters are native to western North America. The genus ''Machaeranthera'' is distinguished from the genus '' Dieteria'' by having once- or twice-pinnate leaves, whereas ''Dieteria'' has entire to toothed leaves.Mojave Desert Wildflowers, Pam MacKay, 2nd Ed. 2013, p. 39 ''Machaeranthera'' means "swordlike

".Great Basin Wildflowers, Laird R. Blackwell, 2006, p. 26 ; SpeciesBiota of North America Program 2013 county distribution maps
/ref>

References

External links

Jepson Manual Treatment

USDA Plants Profile
{{Taxonbar, from=Q547333 Astereae Asteraceae genera