Hipparion

The described specimens have been collected from the Dhok Pathan Formation of the Siwaliks, northern Pakistan. The new material consists of the isolated dentition and reflects morphological features of Sivalhippus nagriensis. The specimens were observed and compared with the previous data. The new discovered material found from the Dhok Pathan type locality identifies the species Sivalhippus nagriensis. The new sample contributes additional information about the species Sivalhippus nagriensis.

Recently collected fossil material in the Villafranchian locality of Sésklo, as well as a re-evaluation of a pre-existing, partly-published museum collection, allow the recognition of a lower faunal level in the locality, older than the main Equus-dominated fossil assemblage, dated in the Early Pleistocene (MNQ17). The lower level yielded, instead, an advanced hipparion, referred to the species Plesiohipparion cf. shanxiense, and a small number of associated taxa: an ostrich (Struthio cf. chersonensis), an unidentified proboscidean, the pig Sus arvernensis, two antelopes (Gazella cf. bouvrainae and Gazellospira torticornis), a large bovid (Bovini indet.), and a rhinoceros (Stephanorhinus sp.). The lower-level fauna is dated in the latest Pliocene (MN16) and indicates a rather open and dry palaeoenvironment. The faunal sequence in Sésklo shows that the hipparion did not co-occur with the stenonid horse, at least in this region. Previous reports on sympatry of these taxa may result from faunal mixing, requiring re-examination of the available samples.

We present the first results on the fossil mammalian fauna recovered during the first excavation season at the new site Pikermi Valley-1 (PV1). The fauna comprises two hipparionine species (C. cf. mediterraneum, H. cf. brachypus), a giraffid (Bohlinia cf. attica), five bovids (Palaeoreas lindermayeri, Protragelaphus skouzesi, Tragoportax cf. amalthea, Gazella sp., Bovidae indet.) and two carnivores (? Adcrocuta eximia, Felidae indet.). The composition of the fauna suggests a Turolian age.

Five Upper Miocene fossil Hipparion molars were studied for U-distribution by Fission Track. U-uptake has reached the whole mass of the teeth and no saturation fronts seem to occur in the interior layers. Mean U-concentration in dentine, cement and enamel was 157, 139 and 78 ppm, respectively. U(enamel)/U(dentine) ~ 0.5 is considerably higher than 0.1 reported in the past for Upper-Quaternary mammoth teeth. These features are disadvantageous for ESR-dating in Hipparion enamel, although a long-lived signal (g=2.00018) is apparent. Leaching phenomena occur in the outer regions of these teeth. Inner enamel folding seems to have hindered a more uniform U-distribution in the teeth.

We describe a hipparion-bearing locality in Hermióni area, Argolis, which is the first so far Neogene land mammal site found in Peloponnese. The bones recovered include cranial and postcranial specimens of a presumably single juvenile individual of Hipparion sp., as well as scarce bones of an indeterminate small bovid.
The upper deciduous teeth are characterised by moderately complex fossette plication, double or triple pli caballin, well-developed hypocone and prominent labial styles. The protocone shape is semicircular to triangular. The lower deciduous molars have shallow and rounded linguaflexids, deep ectoflexids that penetrate the isthmus, well-developed ectostylid and protostylid. There is no pli caballinid. The postcranial bones are characterised by slenderness, as they are juvenile.
Compared to other known hipparionine deciduous toothrows the Hermióni specimens belong to a fairly large-sized hipparion, similar to H. concudense from Spain and H. mediterraneum from Pikérmi. The specific determination is uncertain due to the juvenile status of the available material.
The presence of Hipparion indicates a Late Miocene – Early Pliocene age. A Late Miocene age for Hermióni locality is, however, more probable, as a large part of Peloponnese was submerged during the Pliocene.
Palaeogeographically, the discovery of Hipparion in Peloponnese indicates a wide land connection with the mainland. The additional presence of continental faunas in adjacent islands as Aegina and Crete makes very probable the existence of an extensive Miocene land in southern Greece.

Cooper’s D is a fossil locality in the Bloubank Valley close to other important sites such as Sterkfontein and Kromdraai in Gauteng, South Africa. The fossil deposits of Cooper’s D date to 1.38 ± 0.11 Ma. Hominins like Paranthropus robustus and early Homo have been recovered from Cooper’s Cave. We report here on the Equidae remains. Our sample contains specimens from the extinct Equus capensis, and a specimen which represents an extinct hipparion Eurygnathohippus cf. cornelianus. This particular specimen was previously identified as plains zebra (Equus quagga). The contribution of Equidae to the total fossil assemblage of Cooper’s D is relatively low, and these remains were likely accumulated by various predators such as spotted and brown hyenas and leopards. The Equidae, as well as the other fauna from Cooper’s D supports the existence of grassland, wooded and water components in the vicinity of the site.