The Cambay Formation at Vastan Mine in Gujarat yields the oldest fossil primates known from India. New age estimates suggest that the fossils date from approximately 54.5 Ma (early Ypresian), about 2 million years older than initially thought and comparable in age to early Wasatchian Wa-4 faunas from North America. The Vastan primate fauna comprises predominantly the asiadapine adapoids Marcgodinotius and Asiadapis. Two species of omomyid primates, Vastanomys gracilis and V. major, are much rarer, each known from a single dental specimen. In addition to primate dental remains, Vastan Mine has produced the best preserved early Eocene primate postcranial elements known from anywhere in the world. Here we present new limb bones, including humeri, ulnae, femora, tibiae, and a talus, from three of the recognized primate species. They include the first omomyid postcrania from India: two femora, a talus, and a potential proximal tibia. We also report additional asiadapine postcrania: a pristine femur of Marcgodinotius and the first complete tibia of Asiadapis. Five new humeri (two complete) consist of one asiadapine and four that lack specializations of either group, making allocation difficult. Two ulnae are attributed to indeterminate euprimates due to lack of adequate comparative material. The elements attributed to Vastanomys are more primitive than any other known omomyid postcrania and are only subtly different from those of asiadapines, in contrast to the more distinct postcranial bones of their middle and late Eocene relatives. The femora attributed to Vastanomys exhibit features suggestive of leaping behavior (cylindrical femoral heads, lateral condyle higher than medial, proximal position of the third trochanter), as in other omomyids. However, while the talus of Vastanomys resembles those of omomyids more than those of other primates, features such as the relatively short, medially angled neck, and oval rather than spherical head suggest that Vastanomys was not as specialized for leaping as younger omomyids. Although asiadapines have been described as close to notharctids in morphology, the relatively wider distal femur and symmetrical condyles of Marcgodinotius resemble adapids more than notharctids and may also reflect less leaping. The revised age of the fossils, together with the similarity in morphology of omomyid and asiadapine postcrania, suggests that the postcrania, like the teeth of the most primitive members of each family, are converging toward a common morphology as we approach the base of the Eocene.
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We describe six proviverrine species from the Early Eocene of France. Three species are new: Minimovellentodon russelli sp. nov. from Mutigny [mammal palaeogene (MP)8 + 9], Boritia duffaudi sp. nov. from La Borie (MP8 + 9), and Leonhardtina godinoti sp. nov. from Grauves (MP10). We describe new specimens and propose new generic combinations for three species from MP10: Protoproviverra palaeonictides, Matthodon menui, and Oxyaenoides lindgreni. We also propose a new generic combination for the primitive Eoproviverra eisenmanni (MP7). Matthodon menui was previously considered as a possible oxyaenodontan, but the new fossils clearly support its reference to Hyaenodontida. Leonhardtina godinoti and Ma. menui are the oldest occurrences for these genera, which were previously unknown before the Middle Eocene. Moreover, the discovery of the proviverrine Mi. russelli in Mutigny implies that the Proviverrinae dispersed in Northern Europe between biozone Palaeocene-Eocene (PE) III (Abbey Wood) and biozone PE IV (Mutigny). This also supports a homogenization of the European faunas during the Early Eocene. The dispersal is concomitant with the disappearance of the oxyaenodontans, arfiines, and sinopines (Hyaenodontida) from Europe. The proviverrines may have filled the ecological niches left vacant by the disappearance of the other carnivorous mammals. With 20 genera and over 30 species, proviverrines were successful in Europe. We performed the first phylogenetic analysis comprising almost all the Proviverrinae. Our analyses indicate that the Proviverrinae diversified greatly during the Early Eocene Climatic Optimum and show a general trend towards specialization throughout the Eocene.
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