The wide distribution of the Neotropical freshwater catfish Rhamdia offers an excellent opportunity to investigate the historical processes responsible for modeling South America's hydrogeological structure. We used sequences from cis-Andean and Mesoamerican Rhamdia species to reconstruct and estimate divergence times among cis-Andean lineages, correlating the results with known geological events. Species delimitation methods based on distance (DNA barcoding and BIN) and coalescence (GMYC) approaches identified nine well-supported lineages from the cis-Andean region from sequences available in the BOLD dataset. The cis-Andean Rhamdia lineages diversification process began in Eocene and represented the split between cis-Andean and Mesoamerican clades. The cis-Andean clade contains two principal groups: Northwest clade (MOTUs from Amazon, Essequibo, Paraguay, and Itapecuru basins) and Southeast clade (Eastern Brazilian shield basins (Paraná, Uruguay, Iguaçu, and São Francisco) plus eastern coastal basins). The diversification of the cis-Andean Rhamdia lineages results from vicariance and geodispersion events, which played a key role in the current intricate distribution pattern of the Rhamdia lineages. The wide geographical distribution and large size of the specimens make it attractive to cultivate in different countries of the Neotropical region. The lineages delimitation minimizes identification mistakes, unintentional crossings by aquaculture, and reduces natural stocks contamination.

中文翻译：

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DNA 条形码揭示了三种顺式安第斯鼠李属物种（Siluriformes：七翅目）的隐秘多样性和多样化过程。

新热带淡水鲶鱼 Rhamdia 的广泛分布为研究负责模拟南美洲水文地质结构的历史过程提供了极好的机会。我们使用来自顺安第斯和中美洲 Rhamdia 物种的序列来重建和估计顺安第斯谱系之间的分歧时间，将结果与已知的地质事件相关联。基于距离（DNA 条形码和 BIN）和聚结 (GMYC) 方法的物种定界方法从 BOLD 数据集中可用的序列中确定了来自顺安第斯地区的九个支持良好的谱系。顺安第斯 Rhamdia 谱系多样化过程始于始新世，代表了顺安第斯和中美洲进化枝之间的分裂。顺安第斯进化枝包含两个主要组：西北进化枝（来自亚马逊的 MOTU，埃塞奎博、巴拉圭和伊塔佩库鲁盆地）和东南进化枝（巴西东部地盾盆地（巴拉那、乌拉圭、伊瓜苏和圣弗朗西斯科）加上东部沿海盆地）。顺式-安第斯 Rhamdia 谱系的多样化源于变异和地理分散事件，这在 Rhamdia 谱系当前复杂的分布模式中发挥了关键作用。标本的广泛地理分布和大尺寸使其在新热带地区的不同国家栽培具有吸引力。谱系划定最大限度地减少了识别错误、水产养殖的无意交叉，并减少了自然种群的污染。顺式-安第斯 Rhamdia 谱系的多样化源于变异和地理分散事件，这在 Rhamdia 谱系当前复杂的分布模式中发挥了关键作用。标本的广泛地理分布和大尺寸使其在新热带地区的不同国家栽培具有吸引力。谱系划定最大限度地减少了识别错误、水产养殖的无意交叉，并减少了自然种群的污染。顺式-安第斯 Rhamdia 谱系的多样化源于变异和地理分散事件，这在 Rhamdia 谱系当前复杂的分布模式中发挥了关键作用。标本的广泛地理分布和大尺寸使其在新热带地区的不同国家栽培具有吸引力。谱系划定最大限度地减少了识别错误、水产养殖的无意交叉，并减少了自然种群的污染。