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''Tetracarpaea'' is the only genus in the flowering plant family Tetracarpaeaceae.〔Richard K. Brummitt. 2007. "Tetracarpaeaceae" pages 316-317. In: Vernon H. Heywood, Richard K. Brummitt, Ole Seberg, and Alastair Culham. ''Flowering Plant Families of the World''. Firefly Books: Ontario, Canada. ISBN 978-1-55407-206-4.〕〔Klaus Kubitzki. 2007. "Tetracarpaeaceae" pages 456-457. In: Klaus Kubitski (editor). ''The Families and Genera of Vascular Plants'' volume IX. Springer-Verlag: Berlin;Heidelberg, Germany.〕 Some taxonomists place it in the family Haloragaceae ''sensu lato'', expanding that family from its traditional circumscription to include ''Penthorum'' and ''Tetracarpaea'', and sometimes ''Aphanopetalum'' as well.〔Shuguang Jian, Pamela S. Soltis, Matthew A. Gitzendanner, Michael J. Moore, Ruiqi Li, Tory A. Hendry, Yin-Long Qiu, Amit Dhingra, Charles D. Bell, and Douglas E. Soltis. 2008. "Resolving an Ancient, Rapid Radiation in Saxifragales". ''Systematic Biology'' 57(1):38-57. (see ''External links'' below).〕 ''Tetracarpaea'' has one species, ''Tetracarpaea tasmannica'', an evergreen, bushy shrub from subalpine areas of Tasmania.〔 It is variable in height, from 1.5 to 10 dm. The leaves are shiny and small, with prominent veins, and the ends of the branches are crowded with small, white flowers. It is not known in cultivation, but has been grown from cuttings.〔John W. Wrigley and Murray Fagg. 2003. ''Australian Native Plants'' fifth edition. Reed New Holland, Australia.〕 ''Tetracarpaea'' has an odd mix of characters, and during the nineteenth and twentieth centuries, its affinities remained obscure. It was variously classified by different authors, usually with considerable uncertainty.〔Matthew H. Hils, William C. Dickison, Terry W. Lucansky, and William Louis Stern. 1988. "Comparative anatomy and systematics of woody Saxifragaceae: Tetracarpaea". ''American Journal of Botany'' 75(11):1687-1700.〕 Molecular phylogenetic analysis of DNA sequences has shown that ''Tetracarpaea'' is a member of the Haloragaceae alliance, an informal group composed of the families Aphanopetalaceae, Tetracarpaeaceae, Penthoraceae, and Haloragaceae.〔 These are four of the fourteen 〔Angiosperm Phylogeny Group. 2009. "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III". ''Botanical Journal of the Linnean Society'' 161(2):105-121. (see ''External links'' below).〕 or fifteen〔 families in the order Saxifragales. == Description == The following description is based on information from several sources.〔〔〔〔Armen L. Takhtajan (Takhtadzhian). ''Flowering Plants'' second edition (2009), pages 304-305. Springer Science+Business Media. ISBN 978-1-4020-9608-2. eISBN 978-1-4020-9609-9. (see ''External links'' below)〕〔Frances Bodkin. 1986. "Encyclopaedia Botanica: The Essential Reference Guide to Native and Exotic Plants in Australia". Angus and Robertson, Publishers: New South Wales, Australia; London, England.〕 ''Tetracarpaea tasmannica'' is a glabrous, evergreen, erect and bushy shrub. It is variable in height, usually from 1.5 to 6 dm, but sometimes attaining a height of 1 m and a width of 7 dm. The leaves are elliptic to oblanceolate, about 25 mm long and 8 mm wide, on a petiole about 2 mm long. The veins are prominent and end near the margin. The margins are serrate or crenate. On both surfaces, the epidermis is covered by a thick cuticle. The inflorescences are dense, erect, terminal racemes, up to 5 cm long. The flowers appear in autumn. They are bisexual, actinomorphic, and 5 to 10 mm wide. The 4 sepals persist to the maturity of the fruit. The 4 petals are white and spatulate in shape. The stamens are either 4 or 8 in number. If 4, they are opposite (along the same radii as) the sepals. The anthers are basifixed. The ovary is superior and consists of 4 carpels that are large compared to the rest of the flower. The carpels are usually separate, but occasionally 2 or 3 of them are fused at the base, or rarely, as far as halfway up. They are erect and stipitate with a suture along the ventral side. A placenta runs along each side of the suture and bears 1 to 3 rows of numerous, tiny ovules. The ovules have been described as having one integument〔 or two.〔 The ovary hardly enlarges after anthesis. The fruit consists of 4 follicles joined at the base. The seeds are numerous and about ½ mm long. 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「Tetracarpaea」の詳細全文を読む スポンサード リンク
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