Most plant descriptions focus on differences in reproductive structures, but some lineages, including the genus Anthurium Schott (Araceae), have the vegetative characters as the main source of relevant taxonomic variability. Several herbarium specimens of Anthurium have inaccurate determinations due to the great leaf-blade plasticity conflicting with the typical shape described. To address how much variation exist in natural populations and how the typical shape of the leaf-blade is distributed in these populations, we examine a representative set of samples from the type locality of six species of Anthurium Schott sect. Urospadix Engl. subsect. Obscureviridia Engl. from the Atlantic Forest through the elliptic Fourier analysis (EFA). We performed a EFA to quantify the leaf-blade shape amplitude, along with a qualitative classification matrix. The data were submitted to a multivariate set of methods to confront boundaries between character states and the degree of identification efficiency of each species. Our study is the first to present the proportion in which morphotypes may be distributed in natural populations and the results can help interpret doubtful materials in herbarium collections. Our data demonstrated that each dataset has a distinct morphological signature represented mainly by the mean shape, which may differ from the shape originally described in the protologue. We suggest a criterion to be adopted to improve this character’s effectiveness and use in taxonomic comparisons, which can also be adapted for other laminar structures.

大多数植物描述侧重于生殖结构的差异，但一些谱系，包括红掌属（天南星科），将营养特征作为相关分类变异的主要来源。由于叶片的巨大可塑性与所描述的典型形状相冲突，红掌的几个植物标本馆标本的测定不准确。为了解决自然种群中存在多少变异以及叶片的典型形状如何在这些种群中分布，我们检查了一组来自Anthurium Schott sect六种物种的类型区的代表性样本。Urospadix英语 分节。暗病毒英语。从大西洋森林通过椭圆傅里叶分析 (EFA)。我们执行了一个 EFA 来量化叶片形状的幅度，以及一个定性的分类矩阵。将数据提交给一组多元方法，以解决特征状态之间的界限和每个物种的识别效率程度。我们的研究首次展示了自然种群中形态型的分布比例，其结果有助于解释植物标本馆藏品中的可疑材料。我们的数据表明，每个数据集都有一个独特的形态特征，主要由平均形状表示，这可能与原始描述中最初描述的形状不同。我们建议采用一个标准来提高这个特征在分类比较中的有效性和使用，