Although species delimitation can be highly contentious, the development of reliable methods to accurately ascertain species boundaries is an imperative step in cataloguing and describing Earth's quickly disappearing biodiversity. Spider species delimitation remains largely based on morphological characters; however, many mygalomorph spider populations are morphologically indistinguishable from each other yet have considerable molecular divergence. The focus of our study, the Antrodiaetus unicolor species complex containing two sympatric species, exhibits this pattern of relative morphological stasis with considerable genetic divergence across its distribution. A past study using two molecular markers, COI and 28S, revealed that A. unicolor is paraphyletic with respect to A. microunicolor . To better investigate species boundaries in the complex, we implement the cohesion species concept and use multiple lines of evidence for testing genetic exchangeability and ecological interchangeability. Our integrative approach includes extensively sampling homologous loci across the genome using a RADseq approach (3RAD), assessing population structure across their geographic range using multiple genetic clustering analyses that include structure , principal components analysis and a recently developed unsupervised machine learning approach (Variational Autoencoder). We evaluate ecological similarity by using large‐scale ecological data for niche‐based distribution modelling. Based on our analyses, we conclude that this complex has at least one additional species as well as confirm species delimitations based on previous less comprehensive approaches. Our study demonstrates the efficacy of genomic‐scale data for recognizing cryptic species, suggesting that species delimitation with one data type, whether one mitochondrial gene or morphology, may underestimate true species diversity in morphologically homogenous taxa with low vagility.

中文翻译：

---

综合物种的界线揭示了南部阿巴拉契亚单一嗜牛按蚊（Araneae：Antrodiaetidae）物种复合体的隐性多样性。

尽管物种划定可能会引起高度争议，但准确分类物种边界的可靠方法的开发是分类和描述地球迅速消失的生物多样性的必要步骤。蜘蛛种类的界定仍然主要基于形态特征。但是，许多Mygalomorph蜘蛛种群在形态上彼此无法区分，但具有相当大的分子差异。我们的研究重点是包含两个同养物种的单色牛樟芝种复合体，表现出这种相对形态停滞的模式，在其分布上具有相当大的遗传差异。过去使用两个分子标记COI和28S进行的研究表明，A。unicolor相对于A. microunicolor是易生的。为了更好地研究复合体中的物种边界，我们实施了凝聚力物种概念，并使用多条证据来测试遗传互换性和生态互换性。我们的综合方法包括使用RADseq方法（3RAD）在整个基因组中广泛采样同源基因座，使用包括结构在内的多种遗传聚类分析评估其地理范围内的种群结构，主成分分析和最近开发的无监督机器学习方法（可变自动编码器）。我们通过在基于生态位的分布模型中使用大型生态数据来评估生态相似性。根据我们的分析，我们得出的结论是，该复合体至少还具有一种新物种，并根据以前不太全面的方法确定了物种界限。我们的研究证明了基因组规模的数据对识别隐性物种的有效性，这表明用一种数据类型进行的定界，无论是一种线粒体基因还是形态，都可能低估了易变性的形态同质类群中的真实物种多样性。