Xanthisma gracile
| slender goldenweed annual bristleweed | |
|---|---|
| Scientific classification | |
| Kingdom: | Plantae |
| (unranked): | Angiosperms |
| (unranked): | Eudicots |
| (unranked): | Asterids |
| Order: | Asterales |
| Family: | Asteraceae |
| Genus: | Xanthisma |
| Species: | X. gracile |
| Binomial name | |
| Xanthisma gracile (Nutt.) D.R.Morgan & R.L.Hartm. | |
| Synonyms | |
| |
Xanthisma gracile[1] is a species of annual flowering plant in the Aster or Sunflower Family (Asteraceae) known by the common names slender goldenweed[2] and annual bristleweed.[3]
Range and habitat
It is native the southwestern United States and northern Mexico, where it grows in the deserts and plateaus.
Growth pattern
It is a bristly annual herb growing erect up to 45 centimeters tall.
Leaves and stems
The oval or oblong leaves are 1 to 3 centimeters long and divided into lobes or teeth tipped with bristles.
Flowers and fruit
The inflorescence bears one or more flower heads lined with pointed, roughly hairy phyllaries. The head has a center of many yellow disc florets and a fringe of 16 to 18 yellow ray florets roughly a centimeter long. The fruit is a woolly achene 2 to 3 millimeters long tipped with a pappus.
Genetics
Xanthisma gracile has extra chromosomes that do not have any functional genes (B chromosomes), and about which little is known.[3]
References
- ↑ Mojave Desert Wildflowers, Pam MacKay, 2nd Ed. p. 314
- ↑ "Machaeranthera gracilis". Natural Resources Conservation Service PLANTS Database. USDA. Retrieved 26 June 2015.
- 1 2 Mojave Desert Wildflowers, Pam MacKay, 2nd Ed. 2013, p. 218