In this work is given a taxonomic synopsis of the Urtica species (Urticaceae) occurring in Brazil. Urtica is the largest genus of Urticeae tribe and occurs frequently in humid places, at interior or forest margin, but mainly near human habitations and pastures. Brazil has a wide geographical distribution, founded mainly in Atlantic Forest biome. About its characters, Urtica species have herbaceous habit, presence of glandular stinging trichomes and opposite leaves. For this work, around 800 herbarium materials were analyzed, including types and prototypes, as well as observation of wild populations in the field. Herbarium labels, literature and cultivated specimens were the main information source for distribution, ecology and taxonomic notes. Four species of Urtica were recognized for Brazil: Urtica circularis (Hicken) Sorarú, U. dioica Linnaeus, U. spathulata Smith, U. urens Linnaeus, for which descriptions, identification key, comments about taxonomy, ecological observations and geographical distribution are presented.

中文翻译：

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巴西荨麻（荨麻科）简介

在这项工作中，给出了发生在巴西的荨麻属（荨麻科）的分类概要。荨麻是荨麻科最大的属，经常出现在潮湿的地方，内陆或林缘，但主要靠近人类栖息地和牧场。巴西地理分布广泛，主要建立在大西洋森林生物群落中。关于其特征，荨麻属物种具有草本习性，存在腺刺毛状体和对生叶。在这项工作中，分析了大约 800 种植物标本馆材料，包括类型和原型，以及对野外野生种群的观察。植物标本馆标签、文献和栽培标本是分布、生态学和分类学注释的主要信息来源。巴西确认了四种荨麻：Urtica circleis (Hicken) Soarú、U. dioica Linnaeus、