Scientific name: Amborella trichopoda
Until recently, Amborella trichopoda was a little known plant native to the rainforests of New Caledonia, a small island in the South Pacific. Amborella gained fame after DNA evidence consistently indicated that it is “sister” to all other living flowering plants (Qiu et al., 2000, 2005; Soltis et al., 1999, 2000, 2002; Parkinson et al., 1999; Mathews and Donoghue, 1999; Zanis et al., 2005). This means that Amborella trichopoda is a descendent of the oldest confirmed branch in the flowering plant family tree. It is notable that is also the sole extant (living) species in its line of ancestry.
Amborella trichopoda is a small, evergreen, shrub that occurs only in the moist, shaded understory of tropical mountainside forests of New Caledonia. Plants are unisexual, meaning they will either produce all male or all female flowers; thus, cross-pollination between plants is required for reproduction. Female flowers are both wind and insect pollinated (Thien et al., 2003)
Amborella flowers are tiny, typically about 4-8 mm. The petals and sepals are indistinguishable, so botanists call them tepals. Additionally, there are a variable number tepals (typically around 3-8). A Male flower has anywhere from 6 to 100 flat, reflexed stamens, the male reproductive organs; female flowers bear 3-8 carpels, the female reproduction organs (Thien et al., 2000; Watson and Dallwitz, 2005). If pollinated, female Amborella flowers develop into small red berries, each containing a single seed (See photo).
Author: Heather Fara, University of Florida. Send comments or corrections
Map: Red dot indicates the location of New Caledonia, a small island in the South Pacific. This is the only place in the world that Amborella is found natively. Map created by Heather Fara, University of Florida.
Photos: (a) Female flowers, taken by Sangtae Kim, University of Florida. (b) Male flowers, taken by Bill Laidlaw, National Tropical Botanical Gardens. (c) Mature fruit, taken byJean-Marie Veillon, Faune et Flore de Nouvelle Calédonie
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