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Wiliwili, with the scientific name ''Erythrina sandwicensis'', is a species of flowering tree in the pea family, Fabaceae that is endemic to the Hawaiian Islands. It is the only species of ''Erythrina'' that naturally occurs there. It is typically found in Hawaiian tropical dry forests on leeward island slopes up to an elevation of . ''Wiliwili'' means "repeatedly twisted" in the Hawaiian language and refers to the seedpods, which dehisce, or twist open, to reveal the seeds. ==Description== ''Wiliwili'' trees grow to a height of with a gnarled and stout trunk that reaches in diameter. The bark is smooth, slightly fissured, and covered in gray or black spines up to in length. The bark on the main trunk of mature trees has a distinct orange cast, which is caused by a terrestrial alga. The ''wiliwili'' is summer (dry season) drought deciduous. The dry season usually begins in late April or in May, and trees in the wild typically lose all of their leaves before they bloom.〔 Trees in cultivation may retain much of their foliage through blooming time.〔George W. Staples and Derral R. Herbst. 2005. "A Tropical Garden Flora" Bishop Museum Press: Honolulu, HI, USA. ISBN 978-1-58178-039-0〕 The flowers appear in the first half of the dry season, from April through July.〔 They form on horizontal or nearly horizontal racemes that are long. The flower color may be orange, yellow, salmon, greenish or whitish.〔 Sometimes all of these colors occur in a single population. The standard petal is erect, not enclosing the other petals. Like all of the erythrinas, the wiliwili is pollinated by birds.〔Anne Bruneau. 1996. "Phylogenetic and Biogeographical Patterns in ''Erythrina'' (Leguminosae: Phaseoleae) as Inferred from Morphological and Chloroplast DNA Characters". ''Systematic Botany'' 21(4):587-605.〕 The horizontal raceme and the erect standard are adaptations to pollination by passerine birds.〔Anne Bruneau. 1997. "Evolution and Homology of Bird Pollination Syndromes in ''Erythrina'' (Leguminosae). ''American Journal of Botany'' 84(1):54-71.〕 Many other erythrinas are pollinated by hummingbirds. Pods develop and persist on the tree, with the seeds remaining attached long after the pods have opened. The seeds are dislodged by heavy downpours that generally start around November in the islands. Many seeds germinate quickly, and a well-established seedling can grow to in height before the start of the next dry season. The ''wiliwili'' is an unusual spine-bearer because this is a species that has evolved in the isolated Hawaiian Islands without the presence ungulates or other large herbivores. It is thought to be closely related to ''E. tahitensis'', a tree endemic to the Tahitian Archipelago, and ''E. velutina'', a widespread species found in tropical South America and the Caribbean.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Wiliwili」の詳細全文を読む スポンサード リンク
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