Terrestrial planarians (Platyhelminthes: Tricladida: Terricola) predaceous on terrestrial gastropods

Abstract

[Extract] Triclads, also commonly known as flatworms or planarians, occur in marine, freshwater and terrestrial environments. They form an order within the turbellarian or free-living Platyhelminthes. The Platyhelminthes form a large phylum containing up to 15,000 described species, with many others yet to be described. Platyhelminthes are conventionally divided into the largely free-living 'Turbellaria' and the parasitic Neodermata comprising Trematoda, Monogenea, Udonellidea and Cestoda. It has been argued that the Class Turbellaria is paraphyletic (Ehlers, 1985) and that the name Tillbellaria can no longer be used in the phylogenetic system of the Platyhelminthes (Ax et al., 1988). Nevertheless the taxon Turbellaria serves as a useful repository in the general sense for freeliving and symbiotic planarians (all the non-neodermatans) without implying monophyly of these taxa (Rohde, 1994).