The text file contains the original DNA nucleotide sequence data used in the phylogenetic analyses of Xue et al. (in review), comprising the 13 protein-coding genes and 2 ribosomal gene subunits of the mitochondrial genome. The text file is marked up according to the standard NEXUS format commonly used by various phylogenetic analysis software packages. The file will be parsed automatically by a variety of programs that recognize NEXUS as a standard bioinformatics file format. The first six lines of the file identify the file as NEXUS, indicate that the file contains data for 30 taxa (species) and 13078 characters, indicate that the characters are DNA sequence, that gaps inserted into the DNA sequence alignment are indicated by a dash, and that missing data are indicated by a question mark. The positions of data partitions are indicated in the mrbayes block of commands for the phylogenetic program MrBayes (version 3.2.6) beginning near the end of the file. The mrbayes block also contains instructions for MrBayes on various non-default settings for that program. These are explained in the Methods section of the submitted manuscript. Two supplementary tables in the provided PDF file provide additional information on the species in the dataset, including the GenBank accession numbers for the sequence data (Table S1) and the DNA substitution models used for each of the individual mitochondrial genes and for different codon positions of the protein-coding genes used for analyses in the programs MrBayes and IQ-Tree (version 1.6.8) (Table S2). Full citations for references listed in Table S1 can be found by searching GenBank using the corresponding accession number. The supplemental tables will also be linked to the article upon publication at the journal website.