Dimitar Kovachev

New Chalicotheriidae (Perissodactyla, Mammalia) from the late Miocene of Bulgaria.

Abstract Few fossils have been described from the very rich localities of Kalimantsi in southwestern Bulgaria, and none from Hadjidimovo, in the same area. These deposits have produced one of the best collections of Chalicotheriidae from the late Miocene of Europe, increasing the diversity of the family, and providing the first definite evidence of the co-occurrence of both subfamilies, Chalicotheriinae and Schizotheriinae. The milk dentition of Ancylotherium is described for the first time; it confirms that this genus is close to, but different from, the American Tylocephalonyx. A chalicotheriine skull from Kalimantsi, with a characteristic tooth morphology, is referred to a new genus and species, Kalimantsia bulgarica. A revision of the taxonomy and systematics of European Chalicotheriinae leads us to discard “Macrotherium,” which is a junior synonym of Chalicotherium, to revive Anisodon Lartet for middle Miocene forms, and to suggest the extension of Kalimantsia into the latest Miocene of the Balkans.

On Mesopithecus habitat: Insights from late Miocene fossil vertebrate localities of Bulgaria

The aim of this study is to describe the environments where the cercopithecid Mesopithecus was found during latest Miocene in Europe. For this purpose, we investigate the paleoecology of the herbivorous ungulate mesofauna of three very rich late Miocene fossil localities from southwestern Bulgaria: Hadjidimovo, Kalimantsi and Strumyani. While Mesopithecus has been found in the two first localities, no primate remains have yet been identified in Strumyani. Comparison between localities with and without primates using the herbivore mesofauna allows the cross-corroboration of paleoenvironmental conditions where this primate did and did not live. A multi-parameter statistical approach involving 117 equid and 345 bovid fossil dental and postcranial (phalanges, metapodia, astragali) remains from these three localities provides species to generic-level diet and locomotor habit information in order to characterize the environment in which Mesopithecus evolved. The analysis of dental mesowear indicates that the bovids were mainly mixed feeders, while coeval equids were more engaged in grazing. Meanwhile, postcranial remains show that the ungulate species from Hadjidimovo and Kalimantsi evolved in dry environments with a continuum of habitats ranging from slightly wooded areas to relatively open landscapes, whereas the Mesopithecus-free Strumyani locality was in comparison reflecting a rather contrasted mosaic of environments with predominant open and some more closed and wet areas. Environments in which Mesopithecus is known during the late Miocene were not contrasted landscapes combining open grassy areas and dense forested patches, but instead rather restricted to slightly wooded and homogeneous landscapes including a developed grassy herbaceous layer.

A new Sporadotragus (Bovidae, Mammalia) from the late Miocene of Bulgaria

We provide a systematic revision of the late Miocene caprine genus Sporadotragus Kretzoi, 1968, the type-species of which was described from Samos under the specific epithet schafferi. It is distinct from the poorly known Pseudotragus. Some specimens from Samos are rather distinctive, but the whole morphological variation there encompasses that of Palaeoryx parvidens from Pikermi, and we follow earlier authors in considering the two names as synonymous. New material from two late Miocene localities of south-western Bulgaria, Kalimantsi and Strumyani, is referred to a new species, S. vasili, which is more primitive than the Greek one in some skull features, but not in the horn-core morphology.