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The spermatophytes (from the Greek word "Σπερματόφυτα"), also known as phanerogams or phenogamae, comprise those plants that produce seeds, hence the alternative name seed plants. They are a subset of the embryophytes or land plants. The term phanerogams or phanerogamae is derived from the Greek , ' = "visible", in contrast to the cryptogamae from Greek ' = "hidden" together with the suffix , ', "to marry". These terms distinguished those plants with hidden sexual organs (cryptogamae) from those with visible sexual organs (phanerogamae). ==Description== The living spermatophytes form five groups: *cycads, a subtropical and tropical group of plants with a large crown of compound leaves and a stout trunk, *''Ginkgo'', a single living species of tree, *conifers, cone-bearing trees and shrubs, *gnetophytes, woody plants in the genera ''Ephedra'', ''Gnetum'', and ''Welwitschia'' *angiosperms, (or magnoliophyta) the flowering plants, a large group including many familiar plants in a wide variety of habitats. In addition to the taxa listed above, the fossil record contains evidence of many extinct taxa of seed plants. The so-called "seed ferns" (Pteridospermae) were one of the earliest successful groups of land plants, and forests dominated by seed ferns were prevalent in the late Paleozoic. ''Glossopteris'' was the most prominent tree genus in the ancient southern supercontinent of Gondwana during the Permian period. By the Triassic period, seed ferns had declined in ecological importance, and representatives of modern gymnosperm groups were abundant and dominant through the end of the Cretaceous, when angiosperms radiated. Another Late Paleozoic group of probable spermatophytes were the gigantopterids. 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「Spermatophyte」の詳細全文を読む スポンサード リンク
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