Maximum likelihood gene tree of six Thanasimus species, that was inferred from DNA barcodes with IQ-TREE. A bold “W” indicates the T. undatulus-lineage west of the Rocky Mountains (western lineage). The five columns to the right of the tree indicate delimitations of species as preferred based on total evidence and putative species inferred by four automated species delimitation methods based on DNA barcodes. Mismatches with morphology due to over- or under-splitting are highlighted in yellow. The histogram shows pairwise raw genetic distances of all specimens except outgroups. Ultrafast Bootstraps are displayed on nodes with > 80% support.