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The Cupressaceae or cypress family is a conifer family with worldwide distribution. The family includes 27–30 genera (17 monotypic), which include the junipers and redwoods, with about 130–140 species in total. They are monoecious, subdioecious or (rarely) dioecious trees and shrubs tall. The bark of mature trees is commonly orange- to red- brown and of stringy texture, often flaking or peeling in vertical strips, but smooth, scaly or hard and square-cracked in some species. The leaves are arranged either spirally, in decussate pairs (opposite pairs, each pair at 90° to the previous pair) or in decussate whorls of 3 or 4, depending on the genus. On young plants, the leaves are needle-like, becoming small and scale-like on mature plants of many (but not all) genera; some genera and species retain needle-like leaves throughout their life. Old leaves are mostly not shed individually, but in small sprays of foliage (cladoptosis); exceptions are the leaves on shoots, which develop into branches, which eventually fall off individually when the bark starts to flake. Most are evergreen with the leaves persisting 2–10 years, but three genera (''Glyptostrobus'', ''Metasequoia'' and ''Taxodium'') are deciduous or include deciduous species. The seed cones are either woody, leathery, or (in ''Juniperus'') berry-like and fleshy, with one to several ovules per scale. The bract scale and ovuliferous scale are fused together except at the apex, where the bract scale is often visible as a short spine (often called an ''umbo'') on the ovuliferous scale. As with the foliage, the cone scales are arranged spirally, decussate (opposite) or whorled, depending on the genus. The seeds are mostly small and somewhat flattened, with two narrow wings, one down each side of the seed; rarely (e.g. ''Actinostrobus'') triangular in section with three wings; in some genera (e.g. ''Glyptostrobus'' and ''Libocedrus'') one of the wings is significantly larger than the other, and in some others (e.g. ''Juniperus'', ''Microbiota'', ''Platycladus'' and ''Taxodium'') the seed is larger and wingless. The seedlings usually have two cotyledons, but in some species up to six. The pollen cones are more uniform in structure across the family, 1–20 mm long, with the scales again arranged spirally, decussate (opposite) or whorled, depending on the genus; they may be borne singly at the apex of a shoot (most genera), in the leaf axils (''Cryptomeria''), in dense clusters (''Cunninghamia'' and ''Juniperus drupacea''), or on discrete long pendulous panicle-like shoots (''Metasequoia'' and ''Taxodium''). Cupressaceae is the most widely distributed conifer family, with a near-global range in all continents except for Antarctica, stretching from 71° N in arctic Norway (''Juniperus communis'') south to 55° S in southernmost Chile (''Pilgerodendron uviferum''), while ''Juniperus indica'' reaches 5200 m altitude in Tibet, the highest altitude reported for any woody plant. Most habitats on land are occupied, with the exceptions of polar tundra and tropical lowland rainforest (though several species are important components of temperate rainforests and tropical highland cloud forests); they are also rare in deserts, with only a few species able to tolerate severe drought, notably ''Cupressus dupreziana'' in the central Sahara. Despite the wide overall distribution, many genera and species show very restricted relictual distributions, and many are endangered species. ==Classification== The family Cupressaceae is now widely regarded as including the Taxodiaceae, previously treated as a distinct family, but now shown not to differ from the Cupressaceae in any consistent characteristics. The one exception in the former Taxodiaceae is the genus ''Sciadopitys'', which is genetically distinct from the rest of the Cupressaceae, and is now treated in its own family, Sciadopityaceae. The family Cupressaceae is divided into seven subfamilies, based on genetic and morphological analysis (Gadek ''et al.'' 2000, Farjon 2005; a more complete phylogeny, based on 10,000 nucleotides of plastid, mitochondrial, and nuclear sequence from 122 species, representing all genera is provided in Mao ''et al.'' 2012): A 2010 study of ''Actinostrobus'' and ''Callitris'' places the three species of ''Actinostrobus'' within an expanded ''Callitris'' based on analysis of 42 morphological and anatomical characters. 〔 Piggin, J., and Bruhl, J.J. (2010). () Phylogeny reconstruction of ''Callitris'' Vent. (Cupressaceae) and its allies leads to inclusion of ''Actinostrobus'' within ''Callitris''. ''Australian Systematic Botany'' 23: 69-93. 〕 ==Superlatives== The family is notable for including the largest, tallest, and stoutest individual trees in the world, and also the second longest lived species in the world: Largest - Giant Sequoia, 1486.9 m³ trunk volume Tallest - Coast Redwood, 115.55 m tall Second stoutest - Montezuma Cypress or Ahuehuete, 11.42 m diameter (after African Baobab) Second oldest - Alerce, 3622 years (after Great Basin Bristlecone Pine) In addition to the above, many other members of the family list among the tallest, most massive, stoutest and most long-lived tree species in the world, including Taiwania, Sugi, Western Redcedar, Incense Cedar, Tibetan Cypress, and Formosan Cypress among others. 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「Cupressaceae」の詳細全文を読む スポンサード リンク
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