Phylogenetic tree of Blastocystis sp. subtypes based on SSU rRNA gene sequences. The phylogenetic relationships among different Blastocystis spp. STs were determined using Clustal X and Mega 7 software for genetic distance calculations and tree construction. The tree was constructed employing the maximum likelihood method, utilizing the Tamura-3 parameter model to calculate evolutionary distances. Positions containing gaps and missing data were excluded from the analysis. Bootstrap values were derived from 1,000 replicates to assess the reliability of the tree. In the tree, subtypes are denoted with blue and red fonts to distinguish between known and novel sequences identified in this study.