Lychnophorinae occurs mainly in campos rupestres and cerrados of the Cerrado Domain (Brazil) and are species subject to fire occurrences and intense solar radiation, occupying acid and well-drained soils. Informative characters on the taxonomy of this subtribe were studied considering the leaf and stem morphology and anatomy. In addition, putative synapomorphies and features that probably determined the success of these species in occupying these habitats were identified. Samples of leaves and stems of 52 species were analyzed using usual techniques in plant anatomy. The reconstruction of ancestral states of characters was made in parsimony analysis using the phylogeny established for Lychnophorinae. The analyses indicated two distinct types of stems and a wide variation in foliar features, with the possible occurrence of three synapomorphies for the stems and 11 for the leaves. Adaptive pressures of restricted environments, where most species live, probably directed the evolution of morphological and anatomical diversity in Lychnophorinae.

中文翻译：

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茎和叶结构多样性的进化：Lychnophorinae（菊科）的案例研究

Lychnophorinae 主要出现在 Cerrado 域（巴西）的 Campos rupestres 和 cerrados 中，是易发生火灾和强烈太阳辐射的物种，占据酸性和排水良好的土壤。考虑到叶和茎的形态和解剖结构，研究了该亚部落分类学的信息特征。此外，还确定了可能决定这些物种成功占据这些栖息地的假定突触和特征。使用植物解剖学中的常用技术分析了 52 种植物的叶和茎样本。使用为 Lychnophorinae 建立的系统发育，在简约分析中重建了字符的祖先状态。分析表明两种不同类型的茎和叶特征的广泛变化，茎可能出现 3 个突触，叶可能出现 11 个突触。大多数物种生活的受限环境的适应压力可能指导了 Lychnophorinae 形态和解剖多样性的进化。