Argyroxiphium grayanum
| Argyroxiphium grayanum | |
|---|---|
| Scientific classification | |
| Kingdom: | Plantae | 
| Clade: | Tracheophytes | 
| Clade: | Angiosperms | 
| Clade: | Eudicots | 
| Clade: | Asterids | 
| Order: | Asterales | 
| Family: | Asteraceae | 
| Genus: | Argyroxiphium | 
| Species: | A. grayanum  | 
| Binomial name | |
| Argyroxiphium grayanum | |
Argyroxiphium grayanum, commonly known as the greensword, is a species of flowering plant in the family Asteraceae, and a member of the silversword alliance, a group of over 50 species which are diverse in morphology and habitat but are genetically closely related.
The silversword alliance provides a convincing natural case study in evolution by adaptive radiation, with the greensword representing one extreme of the genus' plasticity. Some Argyroxiphium, including the well-known Haleakala and Mauna Kea silverswords, live in harsh alpine desert-like conditions of heat, sun, wind, and aridity, and are drought-adapted plants capable of storing water as a gel in leaf structures which are normally air pockets in other plants. However, A. grayanum is a bog plant adapted to very different conditions – excessive moisture, lack of regular sunlight, and cool temperatures, and its leaves are non-succulent like those of the related genus Dubautia.