Exploring the phylogeny of the Leptanillinae (Hymenoptera: Formicidae) through high-throughput sequencing and Bayesian total-evidence inference, with accommodation of systematic bias

Ants of the subfamily Leptanillinae (Hymenoptera: Formicidae) are minute and subterranean, with taxonomy impeded by the dissociation of disparate male and female forms. The advent of phylogenomic inference can remedy this dissociation while resolving leptanilline phylogeny with strong statistical support. However, genome-scale molecular data are vulnerable to systematic biases that may result in decisive statistical support for erroneous conclusions, and previous phylogenomic study of the Leptanillinae did not address this, nor attempted to resolve the phylogenetic positions of the several aberrant leptanilline lineages for which UCEs cannot be obtained. I query the phylogeny of the Leptanillinae from ultra-conserved elements (UCEs) using a Bayesian framework and mitigate the effects of several potential systematic biases by replicating analyses using multiple curated UCE alignments. In addition, I implemented Bayesian total-evidence inference from UCEs and male morphological data to resolve the phylogenetic positions of the monotypic former genus Scyphodon and three other enigmatic terminals for which molecular data are unavailable. The phylogeny of the Leptanillinae inferred herein is robust to compositional biases in phylogenomic data. The synonymy of Scyphodon with Leptanilla is confirmed, with the former being recovered within the Leptanilla havilandi species-group with high Bayesian posterior probability, but the phylogenetic positions of the remaining three morphology-only terminals were unresolved by Bayesian total-evidence inference due to insufficient availability phylogenetic information or inferential artifacts.