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The continuous enrichment of the European Pleistocene mammal fossil record leads inevitably to a comprehensive forthcoming review of the biogeographic and evolutionary history of bisons on the continent. New and revised data from the post-Olduvai (<1.8 Ma)-pre-Jaramillo (>1.0 Ma) time span of the Mygdonia basin (N. Greece), exposed here, indicate the presence of a small bison referred to as Bison cf. degiulii (Masini, Palombo & Rozzi, 2013) due to its similarities with the contemporaneous type material from the Italian Peninsula. A series of minor morphometrical changes detected across chronologically successive Mygdonia bison populations is interpreted as local adaptations to harsher environmental conditions. A re-evaluation of several morphological and biometrical features of the European early bison populations in comparison with later and extant taxa leads to the reconfirmation of some characters as taxonomically and phylogenetically important, while questioning others. The results allow recognizing B. degiulii as most likely member of the true bison clade Bison (Bison) Hamilton Smith, 1827 and reconsidering the current B. (Eobison) Flerov, 1972 concept. The data from Mygdonia basin and Northern Greece confirm the short co-occurrence of Bison Hamilton Smith, 1827 and Leptobos Rütimeyer, 1877-1878 in the Balkans and suggest the appearance of at least two bison lineages in Southern Europe between 1.7-1.5 Ma.

The late Pliocene (early Villafranchian, MN 16a) locality of Milia (Grevena, Greece) has yielded numerous remains of mammals, such as zygodons, mastodons, rhinocerotids, hipparions, bovids, cervids, suids, carnivorans and tapirs. Several specimens of chelonians have also been discovered and comprise a small testudinid, a geoemydid and a giant tortoise. The presence of a giant tortoise and the presence of a geoemydid with large dimensions are further examples of the trend towards gigantism evidenced by the diverse fauna of Milia. In terms of taxonomic abundance of extinct turtles, this is the richest locality in Greece. The small testudinid is of particular importance because it preserves a posteriorly flared carapace, as in the extant Testudo marginata, but the posterior carapace is much taller and anteroposteriorly shorter. These characters allow us to erect a new species, Testudo brevitesta sp. nov., and to discuss the presence of the marginated tortoise and closely related forms in Greece. The new taxon is analysed in a phylogenetic context within other extant and extinct testudinids, providing new information on the clade Testudona.

e fossiliferous site of Milia (Grevena, N. Greece) is best known for the excavation of the longest tusks of Mammut borsoni (Hays, 1834) in the world (4.39 m and 5.02 m). In association with this species occur the Tapir Tapirus arvernensis arvernensis Croizet & Jobert, 1828, the Rhinocerotidae Dicerorhinus jeanvireti Guérin, 1972 and the Suidae Sus avernensis arvernensis Croizet & Jobert, 1828. e first species is represented by two fossils corresponding to one adult and one juvenile individual, the second species is represented by 197 identified remains among which 68 are measurable specimens corresponding to eight adult and one juvenile individuals, and the third species by nine specimens. e dimensions are compared with those of European Ruscinian and Villafranchian species from the same families: Tapirus

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