A new species of gerbil (Gerbillidae, Rodentia, Mammalia) from the Early Pliocene of the Iberian Peninsula and its bearing on faunal dispersals during the Messinian (Late Miocene)

In this paper, the new gerbil species Debruijnimys primaevus sp. nov. is described from the Early Pliocene site of La Piquera in central Spain. This species differs from the type species Debruijnimys julii in its smaller dimensions and less developed longitudinal ridges in the lower molars. It can be derived from the Moroccan species Debruijnimys davidi by an increase in size and modification of the shape of the lower molars.

Therefore, it cannot be related to the previously described Protatera almenarensis from other Late Miocene sites in Spain. It is proposed that the entry of the two gerbils into the Iberian Peninsula took place in two different phases during the Lago Mare stage of the Messinian. The first, involving the entry of Protatera almenarensis as well as other African and Asian elements, coincided with the first substage of the Lago Mare phase, between 5.546 and 5.352 Ma.

The second took place during the late stage of the Lago Mare phase, between 5.338 and 5.333 Ma. After the Zanclean flood, members of the genus Debruijnimys persisted in several Pliocene sites of the Iberian Peninsula (D. primaevus sp. nov. and D. julii).