Phylogenetic Position of Neogogatea (Diplostomoidea; Cyathocotylidae)

Neogogatea Chandler and Rausch, 1947, is a small genus of cyathocotylid digeneans parasitic in the intestines of birds of prey. The genus contains only 3 species: 2 from the Nearctic and 1 from the Palearctic. No sequence data from mature, properly identified representatives of Neogogatea were available until now. In the present study, we collected mature adult Neogogatea kentuckiensis (Cable, 1935) Hoffman and Dunbar, 1963, from osprey in Georgia, Florida, and Delaware, and sequenced fragments of the nuclear large ribosomal subunit (28S) gene and cytochrome c oxidase subunit I (COI) mtDNA gene. We used 28S sequence data for phylogenetic inference and COI data for comparisons at the species level. In the phylogenetic tree, N. kentuckiensis was situated in a clade with representatives of the genera Mesostephanus Lutz, 1935, Braunina Wolf, 1903, and an unidentified cyathocotylid cercaria from Australia. The observed variability in the COI gene between our isolates suggests the need for collecting fresh, well-fixed, and mature specimens from a broader geographic range to test for the presence of more than 1 Neogogatea species in New World osprey.