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Zamiaceae
The Zamiaceae are a family of cycads that are superficially palm or fern-like. They are divided into two subfamilies with eight genera and about 150 species in the tropical and subtropical regions of Africa, Australia and North and South America. The Zamiaceae, sometimes known as zamiads, are perennial, evergreen, and dioecious. They have subterranean to tall and erect, usually unbranched, cylindrical stems, and stems clad with persistent leaf bases (in Australian genera). Their leaves are simply pinnate, spirally arranged, and interspersed with cataphylls. The leaflets are sometimes dichotomously divided. The leaflets occur with several sub-parallel, dichotomously branching longitudinal veins; they lack a mid rib. Stomata occur either on both surfaces or undersurface only. Their roots have small secondary roots. The coralloid roots develop at the base of the stem at or below the soil surface. Male and female sporophylls are spirally aggregated into determinate cones that gro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encephalartoideae
The Zamiaceae are a family of cycads that are superficially palm or fern-like. They are divided into two subfamilies with eight genera and about 150 species in the tropical and subtropical regions of Africa, Australia and North and South America. The Zamiaceae, sometimes known as zamiads, are perennial, evergreen, and dioecious. They have subterranean to tall and erect, usually unbranched, cylindrical stems, and stems clad with persistent leaf bases (in Australian genera). Their leaves are simply pinnate, spirally arranged, and interspersed with cataphylls. The leaflets are sometimes dichotomously divided. The leaflets occur with several sub-parallel, dichotomously branching longitudinal veins; they lack a mid rib. Stomata occur either on both surfaces or undersurface only. Their roots have small secondary roots. The coralloid roots develop at the base of the stem at or below the soil surface. Male and female sporophylls are spirally aggregated into determinate cones that grow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diooeae
''Dioon'' is a genus of cycads in the family Zamiaceae. It is native to Mexico and Central America. Their habitats include tropical forests, pine-oak forest, and dry hillsides, canyons and coastal dunes. Description Dioons are dioecious, palmlike shrubs with cylindrical stems, usually with many leaves. The species in the genus Dioon are perennial, evergreen cycads with cylindrical stem axis is partially in the ground. The plant is thickened and made of soft wood, rarely having above ground branches. Leaf bases are persistent or shedding to leave smooth bark. The leaves are pinnate, spirally arranged, interspersed with cataphylls, with leaflets not articulated and lacking a midrib. The lower leaflets are often reduced to spines. The sporophylls are not in vertical rows in cones, and the megasporophyll apices are broadly flattened, upturned, and overlapping. Species in the genus Dioon have 2n = 18 chromosomes. The largest species is D. spinolosum, which are over 16 meters high an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
