Phylogenetic placement of the Onchocerca species from the present case in Japan based on mitochondrial 12S rRNA gene sequences. The tree was constructed using the maximum likelihood method with the Hasegawa-Kishino-Yano model. Evolutionary rate differences among sites were modeled using a discrete Gamma distribution. The final dataset contained 33 sequences with a total of 377 aligned positions. Bootstrap values (≥70%) based on 1,000 replicates are shown next to the branches. The tree was rooted using Brugia malayi and Wuchereria bancrofti as outgroups. The present case (Homo sapiens, Japan) is indicated by a triangle (▲). Host species and geographic origin are shown in parentheses. All analyses were performed using MEGA11 (Tamura et al., 2021) [16]. Scale bar indicates the number of substitutions per site.