Maximum likelihood (ML) phylogenetic tree of freshwater mussels within the subfamily Gonideinae based on a combined DNA sequence dataset of COI, 16S rRNA, and 28S rRNA genes (1,959 bp). Branch support values are indicated on nodes as bootstrap percentages from ML analysis and Bayesian posterior probabilities from BI analysis, and shown as ML/BI. The scale bar represents the estimated evolutionary distance between taxa. The clade of the genus Songkhlanaia is highlighted in blue, and type specimens are indicated by an asterisk (*). Type species of Pseudodontini genera are marked with two asterisks (**).