Amborella

From Wikipedia, the free encyclopedia

Amborella
Amborella buds
Amborella buds
Scientific classification
Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Amborellales
Family: Amborellaceae
Genus: Amborella
Baill.
Species: A. trichopoda
Binomial name
Amborella trichopoda
Baill.

Amborella trichopoda is a rare, vesselless, understory shrub or small tree found only on the island of New Caledonia. It is of great interest in plant systematics because modern molecular systematics data place it at or near the base of the flowering plants. That is, it represents a line of flowering plants that very early on diverged (about 130 million years ago) from all the other extant species of flowering plants. Comparing characteristics of this extant basal angiosperm, more derived flowering plants, and the fossil flowering plants may give us some idea of the characteristics of early flowering plants and how they have evolved, or changed through time.

Amborella trichopoda is a sprawling shrub or small tree with two-ranked leaves without stipules. The leaves are alternately arranged, evergreen, simple, with serrated and rippled margins, and about 8–10 cm long. The plant is dioecious: each flower produces both stamens and carpels, but only one sex develops fully and is fertile in the flowers of an individual plant, the structures of the other sex remaining undeveloped. The small flowers, 4–8 mm across, are in terminal cymose inflorescences or clusters, each flower with a perianth of undifferentiated tepals arranged in a spiral, rather than in the whorls of more derived flowers. The fruit is a red berry containing a single seed, 5–8 mm long.

Individuals of this species in the wild are being reduced by overgrazing and habitat destruction.

[edit] External links