Species conservation with fragmented and endangered populations must be based on a prior and thorough knowledge of the structure and population dynamics. Oophaga lehmanni is a dendrobatid species endemic of Colombia and is restricted to its type locality. This species has a fragmented distribution and is considered as critically endangered mainly due to habitat destruction and overexploitation. Oophaga lehmanni exhibits phenotypic variation in the dorsal color pattern (red and yellow morphs). We reconstructed the overexploitation history that this species has faced in the last 40 years. In addition, we collected genetic and morphological data for the first time in natural populations to describe genetic diversity between and within populations, and to evaluate morphological and genetic differences between red and yellow morphs. Overexploitation data suggest that more than 80.000 (Min = 60.047–Max = 102.236) frogs were extracted from the field in the last four decades, probably generating the local extirpation or population decline from the type locality. Genetic data showed reduced genetic diversity. Observed heterozygosity (mean ± s.d. = 0.599 ± 0.165) is lower than expected (mean ± s.d. = 0.867 ± 0.082). We did not find differences in body size and heterozygosity between the two morphs; however, individuals analyzed were assigned to two genetic clusters, which corresponded to the O. lehmanni-yellow and O. lehmanni-red. In addition, F_ST (0.209) and Nei genetic distance (0.18) values indicated genetic differentiation between the two morphs; therefore, red and yellow morphs should be treated as independent management units. This information will help to define appropriate and long-term conservation units, as a useful tool to mitigate the extinction risk of this species.

具有零散和濒临灭绝种群的物种保护必须基于对结构和种群动态的事先和透彻的了解。Oophaga lehmanni是哥伦比亚的一种树毛类物种特有种，仅限于其类型所在地。该物种分布零散，主要由于生境破坏和过度开发而被视为极度濒危。Oophaga lehmanni表现出背面颜色模式的表型变化（红色和黄色变体）。我们重建了该物种在过去40年中面临的过度开发历史。此外，我们首次收集了自然种群的遗传和形态数据，以描述种群之间和种群内部的遗传多样性，并评估红色和黄色形态之间的形态和遗传差异。过度开发的数据表明，在过去的40年中，从田野中提取了超过80.000（最小= 60.047–最大= 102.236）只青蛙，这可能导致当地物种灭绝或种群数量减少。遗传数据显示遗传多样性降低。观察到的杂合度（平均值±sd = 0.599±0.165）低于预期值（平均值±sd = 0.867±0.082）。我们没有发现两种形态之间的体型和杂合性差异。但是，被分析的个体被分配到两个遗传簇，这对应于O. lehmanni-黄色和O. lehmanni-红色。另外，F _ST（0.209）和Nei遗传距离（0.18）值表明两种形态之间的遗传分化。因此，红色和黄色变体应被视为独立的管理单位。这些信息将有助于确定适当的长期保护单位，作为减轻该物种灭绝风险的有用工具。