Morphological and molecular identification of Neomoliniella longicorpa gen. et sp. nov. (Digenea: Echinostomatidae) from the Eurasian coot Fulica atra (Aves: Rallidae): a taxonomic evaluation

The purpose of the research is the morphological and molecular identification of trematodes found in the intestines of migratory waterfowl with subsequent taxonomic evaluation.
Materials and methods. Mature specimens of trematodes were collected from the intestines of waterfowl (Fulica atra and Aythya ferina) shot during the ecological-faunistic monitoring in the southern part of the Primorsky krai. Preliminary morphological analyze revealed that trematodes belong to the Echinostomatidae family. The whole-mounts of worms from F. atra were prepared using standard methods with alum carmine. Divergent domains of 28S ribosomal RNA gene were sequenced and used to determine systematic position and relationships of discovered species of echinostome by reconstructing Bayesian and Maximum likelihood trees.
Results and discussion. Trematodes found in the coots' intestine, should be described as Neomoliniella longicorpa in the new genus Neomoliniella gen. et sp. nov., which is reliably confirmed by morphological and genetics data. Another cryptic echinostomatid species sister to Neomoliniella gen. nov., and probably representing the separate unknown genus, was demonstrated only on the phylogenetic reconstructions and confirmed by large genetic distances. Currently, this taxon is indicated as Echinostomatidae gen. sp. and more evidence is needed for its validation. We also report about the first detection of Echinostoma paraulum from A. ferina in the south of the Russian Far East. The biology, morphology of each life cycle stage of newly described species of worms should be investigated to test not only their scientific but also medical significance. For the first time in the history of the group, dichotomous keys for eight families of the superfamily
Echinostomatoidea and, to date, the largest of all previously known for the family Echinostomatidae identification chart – dichotomous keys for the identification of 27 Palearctic genera were compiled.

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