Suborders[1]MaricolaCavernicola
Tricladida (triclads)[2] is an order of turbellarians, a group of free-living flatworms. They are also known as planarians, although this common name is also used for a wide number of free-livingplatyhelminthes.[3]
The triclads are characterized by triply branched intestine and anteriorly situated ovaries, next to the brain.
Today the order Tricladida is split into three suborders, according to their phylogenetic relationships:Maricola, Cavernicola andContinenticola. Formerly, the Tricladida was split according to habitats: Maricola, which is marine; Paludicola, which inhabits freshwater; andTerricola, which is land-dwelling.[4]