Abstract
Abstract The genus Gnosonesima (Turbellaria, Lecithoepitheliata) is revised on the basis of all four known species, G. antarctica Reisinger, 1926, G. borealis (Westblad, 1952), G. brattstroemi sp. n., and G. reisingeri sp. n. It is the only genus in the family Gnosonesimidae, constituting together with the family Prorhynchidae the order Lecithoepitheliata. The pharynx in Gnosonesima represents a type of its own, here called coniform (pharynx coniformis). It has no affinity with the pharynx of the prorhynchids. It is a double structure consisting of an internal plicate pharynx and an external muscular structure comparable with the conorhynch of the Eukalyptorhynchia. G. brattstroemi has epidermal pigment ocelli of a primitive type. Unicellular sensory pits are evidently a common feature in the genus Gnosonesima. The tetrapartite (“tetramerous”) ovary and the genito-intestinal pore are discussed from phylogenetic and taxonomic viewpoints. The order Lecithoepitheliata is evidently polyphyletic but can be retained provisionally for practical reasons.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
