Local extinction of genus Carcharias (Elasmobranchii, Odontaspididae) in the eastern Pacific Ocean.

CIONE, A.; MENNUCCI, J.; SANTALUCITA, F.; ACOSTA HOSPITALECHE, C. I. A.

REVISTA GEOLóGICA DE CHILE

Asco. Geol

Año: 2007 vol. 34 p. 139 - 145

0716-0208

Fossil record shows that the distribution of genus Carcharias and probably species C. taurus Rafinesque, 1810 ranged into the western coast of South America during the Miocene and part of the Pliocene. The genus is absent in the area today. We suggest that its local extinction is the consequence of a drop of global temperatures during the middle Pliocene and Pleistocene and the coeval lowering of sea level that 1) shrinked the area of distribution to the northern areas and 2) provoked the disappearance of suitable environments when the shelf area became extremely reduced. After approximately 3 Ma there would not be possible to the species to migrate from the north into the region because the Panamanian isthmus was established.