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The Hawaiian lobelioids are a group of flowering plants in the bellflower family, Campanulaceae, all of which are endemic to the Hawaiian Islands. This is the largest plant radiation in the Hawaiian Islands, and indeed the largest on any island archipelago, with over 125 species. The six genera can be broadly separated based on growth habit: ''Clermontia'' are typically branched shrubs or small trees, up to tall, with fleshy fruits; ''Cyanea'' and ''Delissea'' are typically unbranched or branching only at the base, with a cluster of relatively broad leaves at the apex and fleshy fruits; ''Lobelia'' and ''Trematolobelia'' have long thin leaves down a single, non-woody stem and capsular fruits with wind-dispersed seeds; and the peculiar ''Brighamia'' have a short, thick stem with a dense cluster of broad leaves, elongate white flowers, and capsular fruits. The group contains morphologically divergent species, and was long thought to have derived from at least three introductions: one for ''Lobelia'' and ''Trematolobelia'', one for ''Brighamia'', and one for ''Clermontia'', ''Cyanea'', and ''Delissea''. Based on recent DNA sequence evidence (Givnish et al., 1996, 2008) it now believed that all are derived from a single introduction. This was likely a ''Lobelia''-like species that arrived about 13 million years ago, when Gardner Pinnacles and French Frigate Shoals were high islands and long before the current main islands existed. Many species have beautiful and spectacular flowers, especially those in ''Lobelia'' and ''Trematolobelia''. Unfortunately, they are also highly vulnerable to feeding by feral ungulates such as feral pigs; the stems are only partly woody, and contain few defenses against herbivory. The bark contains a milky (but apparently non-poisonous) latex, and is often chewed by rats and pigs. Seedlings are also vulnerable to disturbance by pig digging, and in areas with high densities of pigs it is not uncommon to find the only lobelioids being epiphytic on larger trees or on fallen logs. ==''Brighamia''== ''Brighamia'' is quite unlike the other genera, with a succulent stem and long, thin, tubular flowers. It was long thought to have been the result of a separate introduction, and its unique combination of characters made it difficult to place. These characters are the result of adaptation to growing on cliffs and pollination by the endemic Hawaiian hawkmoth, ''Manduca blackburni''. This moth is now itself listed as endangered, surviving mainly on the southern slopes of Maui, well away from where ''Brighamia'' live. Some pollination may be done by closely related alien hawkmoths such as the Five-Spotted Hawkmoth (''M. quinquemaculata'') and Pink-spotted Hawkmoth (''Agrius cingulata''). Despite their inaccessible habitat on cliffs, ''Brighamia'' are sometimes hand-pollinated by botanists to ensure seed set. Both species are now extremely rare. The genus is named in honour of the first director of the Bernice P. Bishop Museum, William Tufts Brigham. ''Brighamia'' species *''Brighamia insignis'' * A.Gray – ''Ōlulu'' (Kauai, Niihau†) *''Brighamia rockii'' * H.St.John – ''Pua Ala'' (Molokai, Lānai†, Maui†) † species believed to be extinct * 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「Hawaiian lobelioids」の詳細全文を読む スポンサード リンク
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