Two new tetraphyllidean cestodes are described from the freshwater stingray Potamotrygon magdalenae from Colombia. The new genus Potamotrygonocestus is proposed for P. magdalenensis, which differs ...

Many millions of years ago, we mammals veered from the path of Earth's other inhabitants by evolving a unique skill – the capacity to chew. This newfound ability to chow down on tough foods powered ...

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