Phylogenetic analysis of Blastocystis subtypes in the present study (black filled circles before the accession number) with reference sequence from GenBank based on the SSU rRNA gene fragment by the neighbour-joining method using the Kimura 2-parameter model. Bootstrap values (>50) are indicated at the nodes. Scale bar indicates 0.02 nucleotide substitutions/site. Proteromonas lacertae (U37108) is used as the outgroup.