Phylogenetic relationships of the “pygmaeus” group microphallids based on cox1 sequences. (a) Bayesian phylogenetic tree. Poorly supported nodes (posterior probability < 0.75) were collapsed into polytomies. For nodes also recovered in the maximum likelihood (ML) analysis, both BI and ML support values are shown. (b) Five best ASAP scores and partition numbers (in brackets); and color-coded putative species boundaries corresponding to the clades in the tree.