Argyroxiphium grayanum

Argyroxiphium grayanum

Critically Imperiled  (NatureServe)
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.