特徵描述
作者
YANG, YUEN-PO, SHIH, BING-LING and LIU, HO-YIH
型態特徵
Monoecious, dioecious or rarely polygamous herbs, shrubs, or trees, with or without stinging hairs; cystoliths usually present in epidermal cells. Leaves alternate or opposite, sometimes anisophyllous with nanophylls (reduced leaves), petiolate or sessile, usually stipulate. Inflorescences often cymose glomerules, or sessile and condensed cymes in leaf axils, sometimes a head or a single flower. Flowers minute, unisexual or rarely bisexual, actinomorphic or zygomorphic, mostly green; perianth a single whorl or rarely absent. Male flowers: perianth segments 2-5, mostly free or connate in lower half; stamens 2-5, inflexed in bud, anthers basifixed, longitudinally dehiscent, rudimentary ovary often present. Female flowers: perianth segments 2-5, free or somewhat completely connate; staminodes present or absent; ovary superior, 1-loculed, stigma capitate, penicillate, ligulate or filiform; ovule 1, basal. Fruit an achene or drupe, sometimes enclosed by persistent perianth; seed with thin testa; embryo straight, surrounded by oily endosperm.
屬
About 45 genera with about 1,000 species, widely distributed in the tropical and temperate regions; 21 genera in Taiwan.
參考文獻
Elatostema 樓梯草屬
作者
YANG, YUEN-PO, SHIH, BING-LING and LIU, HO-YIH
型態特徵
Monoecious or dioecious herbs; stems mostly succulent, rarely woody at base. Leaves alternate, very unequal-sided at base, mostly with cystoliths, 3-nerved or penninerved; nanophylls present or absent, opposite normal leaves; stipules 2, intrapetiolar, stipule of nanophyll opposite stipule of normal leaf. Inflorescences mostly many-flowered discoid heads, rarely 1-3-flowered; heads usually two valved, each valve including several glomerules with several flowers and subtended by a few bracteoles. Male flowers: sepals 3-5, connate at base, segments slightly imbricate, usually corniculate or short horned below apex; stamens 3-5. Female flowers: sepals 3-5 or reduced; staminodes 3-5, scale-like, rarely absent; stigma penicillate; ovary straight. Achenes circular in cross section, mostly with longitudinal ribs, rarely smooth.
參考文獻
種列表
- Elatostema acuteserratum 銳齒樓梯草
- Elatostema calcareum
- Elatostema cuneatum 稀齒樓梯草
- Elatostema cyrtandrifolium 台灣樓梯草
- Elatostema edule 食用樓梯草
- Elatostema fenkolensis
- Elatostema flumineorupestre
- Elatostema hirtellipedunculatum 糙梗樓梯草
- Elatostema hypoglaucum 白背樓梯草
- Elatostema kusaiense
- Elatostema lineolatum var. majus 冷清草
- Elatostema microcephalanthum 微頭花樓梯草
- Elatostema novoguineense
- Elatostema oblongifolium 長圓樓梯草
- Elatostema parvum 絨莖樓梯草
- Elatostema platyphyllum 巒大冷清草
- Elatostema rivulare 溪澗樓梯草
- Elatostema sessile var. cuspidatum 樓梯草
- Elatostema stoloniforme
- Elatostema strigillosum 微粗毛樓梯草
- Elatostema subcoriaceum 近革葉樓梯草
- Elatostema trilobulatum 裂葉樓梯草
- Elatostema urvilleanum
- Elatostema villosum 柔毛樓梯草
