Gene tree for CYTB for selected sites of T. californicus. Tree is one of 16 most parsimonious trees based on the complete nucleotide sequence of CYTB (1131 bp) for taxa representing the range of diversity found within each of the regional areas and the additional site sequences. Bootstrap numbers based upon 10 000 replicates are given above branches (only those supporting regional clades and branches showing the relationships of additional sites are shown). T. japonicus nucleotide CYTB sequences from both Korea and Japan are used to root tree (from GenBank accession numbers AY959338 and AB060648 respectively). The relationships between the regions and additional sites are the same as those obtained in a Bayesian phylogenetic analysis. Credibility values from this analysis are given below each branch.