A simplified phylogenetic tree of the phylum Nematoda. The phylogeny, simplified from [3, 4], emphasises the position of the main study species R. culicivorax, T. spiralis and C. elegans. Species with a published genome and mentioned in Table 1 are in black. Currently no genomic data are available for Enoplia (Clade II). The order of branching of the basal nodes of Nematoda is currently unresolved.