What is a Cretaceous sawfish doing in a Miocene forest?

Description: Reworked fossils are rare and fascinating components of the palaeontological record, which can preserve evidence of unique post-mortem histories. As the name implies, such fossils are usually eroded out of the deposit in which they were originally entombed, and subsequently transported and re-buried in a younger bed (Donovan et al., 2010). This is the case with a tooth of Ptychotrygon triangularis, a batoid from Cretaceous seas, found between Miocene mammal remains in the Ribesalbes-Alcora Basin.
https://www.researchgate.net/publication/301802996_What_is_a_Cretaceous_sawfish_doing_in_a_Miocene_forest

Get full text: http://repositorio.educacionsuperior.gob.ec/handle/28000/4942