Suidae Transition at the Miocene-Pliocene Boundary: a Reassessment of the Taxonomy and Chronology of Propotamochoerus provincialis

Alessio Iannucci,Leonardo Sorbelli,Raffaele Sardella,Marco Cherin

doi:10.1007/s10914-020-09521-w

Abstract

The Miocene-Pliocene (Turolian-Ruscinian) transition represents a fundamental interval in the evolution of Euro-Mediterranean paleocommunities. In fact, the paleoenvironmental changes connected with the end of the Messinian salinity crisis are reflected by a major renewal in mammal faunal assemblages. An important bioevent among terrestrial large mammals is the dispersal of the genus Sus, which replaced all other suid species during the Pliocene. Despite its possible paleoecological and biochronological relevance, correlations based on this bioevent are undermined by the supposed persistence of the late surviving late Miocene Propotamochoerus provincialis. However, a recent revision of the type material of this species revealed an admixture with remains of Sus strozzii, an early Pleistocene (Middle Villafranchian to Epivillafranchian) suid, questioning both the diagnosis and chronological range of P. provincialis. Here we review the late Miocene Suidae sample recovered from the Casino Basin (Tuscany, central Italy), whose taxonomic attribution has been controversial over the nearly 150 years since its discovery. Following a comparison with other Miocene, Pliocene, and Pleistocene Eurasian species, the Casino Suidae are assigned to P. provincialis and the species diagnosis is emended. Moreover, it is recognized that all the late Miocene (Turolian) European Propotamochoerus material belongs to P. provincialis and that there is no compelling evidence of the occurrence of this species beyond the Turolian-Ruscinian transition (MN13-MN14).

Highlights

The late Miocene was a period of dramatic changes at a global scale (Cerling et al 1997; Herbert et al 2016), which led to the physiographic separation of the Mediterranean Sea from the Atlantic Ocean (Krijgsman et al 1999)
Geraads et al (2008) described as Propotamochoerus sp. several remains from the late Miocene of the Balkans (Macedonia and Bulgaria), arguing that they may represent an Aegean species distinct from other European (P. palaeochoerus and P. provincialis) and Asian (P. hysudricus and P. hyotherioides) forms
According to the original diagnosis, P. aegaeus should differ from P. provincialis in the following features: 1) smaller dimensions; 2) presence of diastemata between C, P1, and P2; 3) P1 with two roots; 4) P2 longer than P3

Summary

Introduction

The late Miocene was a period of dramatic changes at a global scale (Cerling et al 1997; Herbert et al 2016), which led to the physiographic separation of the Mediterranean Sea from the Atlantic Ocean (Krijgsman et al 1999). At the Miocene-Pliocene boundary, the Messinian salinity crisis reached its acme and after that ended with an abrupt —if not properly catastrophic (Garcia-Castellanos et al 2009)— restoration of the. The impact of this transition was strong on the carnivoran guild, featuring the extinction of more than 90% of the species (Werdelin and Turner 1996), but was significant among ungulates. Sus arvernensis Croizet and Jobert, 1828, was one of the few species capable of taking advantage of the change. It represents the earliest member of a very successful genus that replaced all other suine species during the Pliocene (Frantz et al 2016).

Methods

Findings

Discussion

Conclusion