Carranza et al. (1998) have proposed that the Paludicola is paraphyletic and that the Dugesiidae and Terricola share a common ancestor not shared with the other paludicolan triclads. Their evidence comes from molecular cladistics of 18S rDNA and 18S rRNA. They tentatively propose the name "Continenticola" for the group encompassing paludicolan families and the Terricola but do not establish a formal revision. (Perhaps the remaining triclads would be Incontinenticola.)

Their phylogenetic tree would suggest this classification:

• Tricladida
  • Maricola
  • Cavernicola
  • Contintenticola
    • Planariidae
    • Dendrocoelidae
    • Unnamed taxon
      • Dugesiidae
      • Terricola

Carranza S, Littlewood DTJ, Clough KA, Ruiz-Trillo I, Baguna J, Riutort M (1998) A robust molecular phylogeny of the Tricladida (Platyhelminthes: Seriata) with a discussion on morphological synapomorphies. Proc Roy Soc Lond B 265: 631-640