| monogenoidean parasites of freshwater stingrays (rajiformes: potamotrygonidae) from the negro river, amazon, brazil: species of potamotrygonocotyle (monocotylidae) and paraheteronchocotyle (hexabothriidae). | five new species of potamotrygonocotyle (monocotylidae) are described and paraheteronchocotyle amazonense mayes, brooks et thorson, 1981 (hexabothriidae) is redescribed from monogenoideans collected on the gills of species of potamotrygonidae from the negro river, amazon, brazil. potamotrygonocotyle quadracotyle sp. n. and p. umbella sp. n. were found parasitizing an undescribed species of potamotrygon; potamotrygonocotyle rarum sp. n. is described from potamotrygon schroederi; potamotrygonocoty ... | 2007 | 19245189 |