A large subclass of the class Magnoliopsida (dicotyledons) of the division Magnoliophyta (Angiospermae), the flowering plants, consisting of 11 orders, 49 families, and more than 60,000 species. The Asteridae are mostly sympetalous with unitegmic, tenuinucellate ovules and with the stamens usually as many as, or fewer than, the corolla lobes and alternate with them. Most of them have two carpels, but a few have as many as five or even more carpels, and a few others are pseudomonomerous. The largest orders of the group are the Asterales (about 20,000 species), Scrophulariales (about 11,000 species), Lamiales (about 7800 species), and Rubiales (about 6500 species). Other orders are the Gentianales, Plantaginales, Solanales, Callitrichales, Campanulales, Calycerales, and Dipsacales. See individual articles on each order.
- 词性: noun
- 行业/领域: 科学
- 类别 普通科学
- Company: McGraw-Hill
创建者
- Francisb
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