A Miocene cusk-eel (Ophidiiformes : Ophidiidae) from Peninsula Valdes, Argentina

Genypterus valdesensis. sp. nov. from the Puerto Madryn Formation in Penins ula Valdes, Argentina is the first fossil ophidiid reported from South Amer ica and represents the first well preserved record of the genus worldwide. The specimen consists of a nearly complete articulated skull and some disar ticulated postcranial elements. A thorough description is given of the oste ological features of the species, which can be used to recognize it as a di stinct taxon. The fossil species is characterized by the presence of a fora men on infraorbital 3 and by the square-shape of infraorbital 4. An array o f morphological features taken in combination contribute to further differe ntiate G. valdesensis from the Recent species. This specimen also provides unequivocal evidence of the presence of the Ophidiiformes in the southweste rn Atlantic Ocean 14 MA.