ABSTRACT Identifying discontinuous entities within species complexes is a major topic in systematic and evolutionary biology. Comprehensive inventories describing and identifying species rapidly and correctly before they or their habitats disappear is especially important in megadiverse regions, such as South America continent, where a large part of the biodiversity is still unknown and remains to be discovered. Species complexes may account for a substantial number of plant groups in the South American flora, and studies investigating species boundaries in such challenging groups are needed. In this context, multidisciplinary approaches are crucial to understanding the species integrity and boundaries within species complexes. Morphometrics, cytogenetics, anatomy, crossing experiments, and molecular markers have been combined in different ways to investigate species complexes and have helped depict the mechanisms underlying the origin of South American species. Here, we review the current knowledge about plant species complexes on the hyperdiverse South American continent based on a detailed examination of the relevant literature. We discuss the main findings in light of the potential evolutionary mechanisms involved in speciation and suggest future directions in terms of integrating multispecies coalescence methods with several complementary types of morphological, ecological, and geographical data in this research field.

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植物物种复合体作为理解物种形成和进化的模型：南美研究回顾

摘要识别物种复合体中的不连续实体是系统和进化生物学的一个主要课题。在物种或其栖息地消失之前快速准确地描述和识别物种的综合清单在南美洲大陆等生物多样性丰富的地区尤为重要，那里的大部分生物多样性仍然未知并有待发现。物种复合体可能占南美植物群的大量植物群，需要研究调查这些具有挑战性的群中的物种边界。在这种情况下，多学科方法对于理解物种复合体中的物种完整性和边界至关重要。形态计量学、细胞遗传学、解剖学、交叉实验、和分子标记以不同的方式结合以研究物种复合体，并有助于描述南美洲物种起源的潜在机制。在这里，我们根据对相关文献的详细检查，回顾了目前关于高度多样化的南美洲大陆植物物种复合体的知识。我们根据物种形成所涉及的潜在进化机制讨论了主要发现，并在将多物种合并方法与该研究领域中几种互补类型的形态学、生态学和地理数据相结合方面提出了未来的方向。我们根据对相关文献的详细检查，回顾了目前关于高度多样化的南美洲大陆植物物种复合体的知识。我们根据物种形成所涉及的潜在进化机制讨论了主要发现，并在将多物种合并方法与该研究领域中几种互补类型的形态学、生态学和地理数据相结合方面提出了未来的方向。我们根据对相关文献的详细检查，回顾了目前关于高度多样化的南美洲大陆植物物种复合体的知识。我们根据物种形成所涉及的潜在进化机制讨论了主要发现，并在将多物种合并方法与该研究领域中几种互补类型的形态学、生态学和地理数据相结合方面提出了未来的方向。