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The Dipterocarpaceae are a family of 17 genera and approximately 500 species of mainly tropical lowland rainforest trees. The family name, from the type genus ''Dipterocarpus'', is derived from Greek (''di'' = two, ''pteron'' = wing and ''karpos'' = fruit) and refers to the two-winged fruit. The largest genera are ''Shorea'' (196 species), ''Hopea'' (104 species), ''Dipterocarpus'' (70 species), and ''Vatica'' (65 species).〔Ashton, P.S. Dipterocarpaceae. In ''Tree Flora of Sabah and Sarawak,'' Volume 5, 2004. Soepadmo, E., Saw, L. G. and Chung, R. C. K. eds. Government of Malaysia, Kuala Lumpur, Malaysia. ISBN 983-2181-59-3〕 Many are large forest emergent species, typically reaching heights of 40–70 m tall, some even over 80 m (in the genera ''Dryobalanops'',〔 ''Hopea''〔(【引用サイトリンク】 Borneo )〕 and ''Shorea''),〔 with the tallest known living specimen (''Shorea faguetiana'') 88.3 m tall.〔 The species of this family are of major importance in the timber trade. Their distribution is pantropical, from northern South America to Africa, the Seychelles, India, Indochina, Indonesia and Malaysia.〔Simon Gardner, Pindar Sidisunthorn and Lai Ee May, 2011. ''Heritage Trees of Penang''. Penang: Areca Books. ISBN 978-967-57190-6-6〕 The greatest diversity of Dipterocarpaceae occurs in Borneo.〔Ashton, P.S. Dipterocarpaceae. ''Flora Malesiana'', 1982 Series I, 92: 237-552〕 Some species are now endangered as a result of overcutting, extensive illegal logging and habitat conversion. They provide valuable woods, aromatic essential oils, balsam, resins and are a source for plywood. ==Classification== The dipterocarp family is generally divided into three subfamilies: |label2=Monotoideae |2= |label3=Pakaraimoideae |3= }} }} }} * Dipterocarpoideae: the largest of the subfamilies, it contains 13 genera and about 475 species. Distribution includes the Seychelles, Sri Lanka, India, Southeast Asia to New Guinea, and a large distribution in Borneo, where they form the dominant species in the lowland forests. North Borneo (Brunei, Sabah and Sarawak) is the richest area in the world for dipterocarp species.〔 The Dipterocarpoideae can be divided morphologically into two groups,〔〔Maury-Lechon, G. and Curtet, L. Biogeography and Evolutionary Systematics of Dipterocarpaceae. In ''A Review of Dipterocarps: Taxonomy, ecology and silviculture'', 1998. Appanah, S. and Turnbull, J. M. eds. Center for International Forestry Research, Bogor, Indonesia. ISBN 979-8764-20-X〕 and the tribe names Shoreae and Dipterocarpeae are sometimes used, but genetic evidence so far does not support this division: * *Valvate - Dipterocarpeae group (''Anisoptera, Cotylelobium, Dipterocarpus, Stemonoporus, Upuna, Vateria, Vateriopsis, Vatica''). The genera of this group have valvate sepals in fruit, solitary vessels, scattered resin canals, and basic chromosome number x = 11. * * Imbricate - Shoreae group (''Balanocarpus, Hopea, Parashorea, Shorea''). The genera of this group have imbricate sepals in fruit, grouped vessels, resin canals in tangential bands, and basic chromosome number x = 7. A recent molecular study suggest that the genus ''Hopea'' forms a clade with ''Shorea'' sections ''Anthoshorea'' and ''Doona'', and should be merged into ''Shorea''.〔 * Monotoideae: 3 genera, 30 species. ''Marquesia'' is native to Africa. ''Monotes'' has 26 species, distributed across Africa and Madagascar. ''Pseudomonotes'' is native to the Colombian Amazon. * Pakaraimoideae: contains a single species, ''Pakaraimaea roraimae'', found in the Guaianan highlands of South America. A recent genetic study found that the Asian dipterocarps share a common ancestor with the Sarcolaenaceae, a tree family endemic to Madagascar.〔M. Ducousso, G. Béna, C. Bourgeois, B. Buyck, G. Eyssartier, M. Vincelette, R. Rabevohitra, L. Randrihasipara, B. Dreyfus, Y. Prin. The last common ancestor of Sarcolaenaceae and Asian dipterocarp trees was ectomycorrhizal before the India-Madagascar separation, about 88 million years ago. ''Molecular Ecology'' 13: 231 January 2004.〕 This suggests that ancestor of the Dipterocarps originated in the southern supercontinent of Gondwana, and that the common ancestor of the Asian dipterocarps and the Sarcolaenaceae was found in the India-Madagascar-Seychelles land mass millions of years ago, and were carried northward by India, which later collided with Asia and allowed the dipterocarps to spread across Southeast Asia and Malaysia. The first dipterocarp pollen has been found in Myanmar (which at that time was part of the Indian plate) and it dates from the upper Oligocene.〔Morley, R.J. 2000. Origin and Evolution of Tropical Rain Forests. Wiley-Blackwell, NY.〕 The sample appears to slowly increase in terms of diversity and abundance across the region into the mid-Miocene〔 Chemical traces of dipterocarp resins have been found dating back to the Eocene of India. 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「Dipterocarpaceae」の詳細全文を読む スポンサード リンク
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