| Helenium quadridentatum | |
|---|---|
_(16585970589).jpg)
| |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Asterales |
| Family: | Asteraceae |
| Genus: | Helenium |
| Species: | H. quadridentatum |
| Binomial name | |
| Helenium quadridentatum Labill. 1792 | |
| Synonyms | |
| |
Helenium quadridentatum is a North American plant in the family Asteraceae, commonly known as longdisk sneezeweed. It is found in the southeastern and south-central United States (Alabama, Mississippi, Louisiana, Texas, Oklahoma) as well as Mexico (from Tamaulipas to Yucatán), Cuba, Guatemala, and Belize.
Helenium quadridentatum is an annual herb up to 100 cm (39.5 in) tall, with small wings running down the sides of the stems. Leaves are sometimes broadly elliptical, other times very narrow and grass-like. One plant generally produces up to 50 flower heads, in a branching array. Each head has an egg-shaped or conical disc containing can have 500 or more minuscule disc flowers each 1.1–1.8 mm (0.043–0.071 in) across, each yellow toward the bottom but yellow-brown toward the tip. There are also 10-15 yellow ray flowers.
References
- The Plant List, Helenium quadridentatum Labill.
- ^ Flora of North America, Helenium quadridentatum Labillardière, 1792. Longdisk sneezeweed
- Biota of North America Program 2014 county distribution map
- Balick, M. J., M. H. Nee & D.E. Atha. 2000. Checklist of the vascular plants of Belize. Memoirs of The New York Botanical Garden 85: i–ix, 1–246
- Turner, B. L. 2013. The comps of Mexico. A systematic account of the family Asteraceae (chapter 11: tribe Helenieae). Phytologia Memoirs 16: 1–100
- Labillardière, Jacques Julien Houtou de. 1792. Actes de la Société d'Histoire Naturelle de Paris 1: pages 22-23 diagnosis in Latin, description + commentary + figure captions in French
- Labillardière, Jacques Julien Houtou de. 1792. Actes de la Société d'Histoire Naturelle de Paris 1: plate IV (4) full-page line drawing of Helenium quadridentatum
External links
Media related to Helenium quadridentatum at Wikimedia Commons
 | This Asteroideae article is a stub. You can help Misplaced Pages by expanding it. |