Oval frogs (Elachistocleis) have a broad geographic distribution covering nearly all of South America and parts of Central America. They also have a large inter- and intraspecific variation of the few morphological characters commonly used as diagnostic traits among species of the genus. Based on molecular data, we provide the most complete phylogeny of Elachistocleis to date, and explore its genetic diversity using distance-based and tree-based methods for putative species delimitation. Our results show that at least two of the most relevant traditional characters used in the taxonomy of this group (belly pattern and dorsal median white line) carry less phylogenetic information than previously thought. Based on our results, we propose some synonymizations and some candidate new species. This study is a first major step in disentangling the current systematics of Elachistocleis. Yet, a comprehensive review of morphological data is needed before any new species descriptions can be properly made.

中文翻译：

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两个肚子的故事：椭圆形青蛙的系统学（Anura：Microhylidae：Elachistocleis Parker，1927）

椭圆形青蛙（Elachistocleis）的地理分布范围很广，几乎覆盖了整个南美洲和中美洲的部分地区。它们还具有通常用作该属物种间诊断特征的少数形态特征的大的种间和种内变异。基于分子数据，我们提供了迄今为止最完整的 Elachistocleis 系统发育，并使用基于距离和基于树的方法进行假定的物种划界来探索其遗传多样性。我们的研究结果表明，该组分类学中使用的至少两个最相关的传统特征（腹部模式和背中线白线）携带的系统发育信息比以前认为的要少。根据我们的结果，我们提出了一些同义词和一些候选新物种。这项研究是解开当前 Elachistocleis 系统学的第一个重要步骤。然而，在正确进行任何新物种描述之前，需要对形态数据进行全面审查。