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Urticaceae

蕁麻科

特徵描述
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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.

About 45 genera with about 1,000 species, widely distributed in the tropical and temperate regions; 21 genera in Taiwan.

參考文獻

Debregeasia 水麻屬

作者

YANG, YUEN-PO, SHIH, BING-LING and LIU, HO-YIH

型態特徵

Monoecious or dioecious shrubs or small trees. Leaves alternate, serrate-crenate, rugose above, often with snow white or silvery hairs beneath; stipules intrapetiolar, bifid. Inflorescences capitate glomerules axillary, sessile or in lax cymes. Male flowers: perianth 4-partite, rarely 3- or 5-partite, segments valvate; stamens 4, rarely 3 or 5; rudimentary ovary glabrous or somewhat lanate. Female flowers: perianth ovoid or obovoid, fleshy in fruit; ovary erect, included; stigma penicillate, caducous; receptacle fleshy in fruit. Achenes closely enclosed by the fleshy perianth and adnate to it.

參考文獻

標本列表

學名 中名 標本數