| 词条 | Machaeranthera |
| 释义 |
|name = tansyasters |image = Machaeranthera-asteroides-20071030.jpg |image_caption = Machaeranthera asteroides |regnum = Plantae |unranked_divisio = Angiosperms |unranked_classis = Eudicots |unranked_ordo = Asterids |ordo = Asterales |familia = Asteraceae |genus = Machaeranthera |type_species=Aster tanacetifolius[1] |type_species_authority =Kunth. |genus_authority = Nees |synonyms_ref=[2] |synonyms=*Hesperastrum A.Gray
|}}Machaeranthera is a genus of North American flowering plants in the daisy family which are known by the common name tansyaster.[3][4] 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 in the disc florets 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.[4] The genus Machaeranthera is distinguished from the genus Dieteria by having once- or twice-pinnate leaves, whereas Dieteria has entire to toothed leaves.[5] Machaeranthera means "swordlike anthers".[6]
}} References1. ^Tropicos, Machaeranthera Nees 2. ^1 Flann, C (ed) 2009+ Global Compositae Checklist{{dead link|date=January 2018 |bot=InternetArchiveBot |fix-attempted=yes }} 3. ^Nees von Esenbeck, Christian Gottfried Daniel. 1832. Genera et Species Asterearum 13, 224–225 4. ^1 Flora of North America Vol. 20 Page 394 Machaeranthera Nees, Gen. Sp. Aster. 13, 224. 1832. 5. ^Mojave Desert Wildflowers, Pam MacKay, 2nd Ed. 2013, p. 39 6. ^Great Basin Wildflowers, Laird R. Blackwell, 2006, p. 26 7. ^Biota of North America Program 2013 county distribution maps External links
2 : Astereae|Asteraceae genera |
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