Maximum likelihood (ML) tree inferred from SSU rDNA sequences showing the systematic position of Heterogastrostyla salina nov. spec. (bold) and other Gastrostyla-like species (frames with arrows). Numbers near nodes are nonparametric bootstrap values for ML and posterior probability values for Bayesian inference (BI). “-” refers to disagreement in topology with the BI tree. All branches are drawn to scale. We have omitted most names of higher taxa because, as in most (all?) other trees, the taxa are non-monophyletic. The scale bar corresponds to 0.01 expected substitutions per site.