Maximum likelihood (ML) inference and Bayesian inference (BI) based on the ITS + 28S sequence data showing the phylogenetic relationships of representatives of Rhabdiasidae. Caenorhabditis elegans Dougherty (Rhabditida: Rhabditidae) was chosen as the out-group. Bootstrap values ≥70 and Bayesian posterior probabilities values ≥0.90 are shown in the phylogenetic trees. Bold indicates Rhabdias macrocephalum n. sp.