Fecampiida is an order of flatworms in the class Rhabditophora. It is a considerably recent clade, erected after molecular studies.[1]
The order Fecampiida, as currently defined, was erected based on molecular studies.[2] They all are parasitic organisms and are united by a similar development of the basal bodies during spermiogenesis.[3]
Three families of Fecampiida were initially classified in different flatworm orders: Urastomatidae and Genostomatidae were considered prolecithophorans, while Fecampiidae was considered a rhabdocoel. When the genus Notentera was discovered, its relationship with Fecampiidae was clear based on morphology, and both groups were united under Fecampiida.[3] Further ultrastructural studies suggested that Urastomatidae and Genostomatidae were closely related to Fecampiidae and Notenteridae, which was confirmed by molecular studies.[4]
Due to similarities in the protonephridial flame bulb, sperm and spermiogenesis, as well as the parasitic lifestyle, fecampiids were thought to be closely related to neodermatans,[3] but molecular studies revealed them to be more closely related to triclads and prolecithophorans.[4]
Fecampiida is an order of flatworms in the class Rhabditophora. It is a considerably recent clade, erected after molecular studies.
