Fig. 2.

Phylogenetic tree constructed with the nucleotide sequences of 16S rRNA gene using Neighbor-Joining method. The tree was constructed with 299-bp of 16S rRNA gene sequences of D. gallinae in Japan determined in this study and those of other countries obtained from the database. Haplotypes found in Japan were designated based on the 397-bp of 16S rRNA gene of D. gallinae obtained from 239 samples and are shown in boldface in the tree. Other sequences obtained from the database are shown with the accession number and the country where the mites were detected. Bootstrap values more than 600 are shown. The haplotypes found in Japan clustered in two haplogroups. Subsequently, the haplotypes in each haplogroup diverged into two lineages designated as sub-haplogroups, AJ1 and AJ2, and BJ1 and BJ2, respectively. These sub-haplogroups are indicated with the thin vertical lines. Sub-haplogroups AJ2 and BJ1 are closely related to the sequences found in European countries. However, the sub-haplogroups AJ1 and BJ2 are relatively distant from the haplotypes found in other countries.