Abstract

The sigmodontine rodent Oecomys catherinae has been recognized as a species complex that includes five different lineages distributed throughout Brazil south of the Amazon river, named in literature according to their geographic position (central, eastern, northern, western, and westernmost). The western lineage also has been referred as Oecomys aff. catherinae in the literature, because it may represent a distinct species. Herein, we used molecular and morphological data to investigate the possible species distinctiveness within the O. catherinae complex. From molecular analyses, we recovered the western lineage as a monophyletic group with high genetic divergence from the other lineages of the complex. This lineage can be differentiated from other lineages of the O. catherinae complex and other congeners through a combination of mensural and morphological characters that includes: smaller size; posterior margin of nasals usually surpassing the maxillary–frontal suture; supraorbital crest moderately developed, similar to the temporal crest; parietal slightly expanded laterally; subsquamosal fenestra present; alisphenoid strut absent; and anterior cingulum of M1 present. The western lineage occurs in the southern Amazonia, in sympatry with the westernmost lineage and other species of Oecomys. Herein we describe this lineage as a new species, increasing to 19 the number of species within Oecomys.

中文翻译：

---

综合分析支持了来自亚马逊藻的新的Oecomys catherinae复合体（Rodentia，Cricetidae）

摘要

西格莫达汀啮齿动物Oecomys catherinae被认为是一个物种复合体，包括分布在亚马逊河以南的巴西的五个不同谱系，根据其地理位置（中央，东部，北部，西部和最西部）在文献中进行了命名。西方血统也被称为Oecomys aff。凯瑟琳娜在文献中，因为它可能代表一个独特的物种。在这里，我们使用分子和形态数据来研究O内可能的物种独特性。凯瑟琳复杂的。通过分子分析，我们将西部谱系恢复为一个单系群，与该复合体的其他谱系具有高度的遗传差异。该血统可以与O的其他血统区分开。凯瑟琳娜综合体和其他同类物，通过结合心理和形态特征，包括：较小的体积；鼻后缘通常超过上-额线缝合；眶上c适度发育，与颞c相似；顶叶稍向侧面扩展；出现下颌骨窗孔; 不存在斜线状的支柱；M1前扣带存在。西方血统发生在南部的亚马逊，在同域与西部的血统和其他物种的屋鼠属。在本文中，我们将该谱系描述为一个新物种，在Oecomys中的物种数量增加到19个。