Wyniki wyszukiwania

1

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

New dental elements of the oldest proviverrine mammal from the early Eocene of Southern France support possible African origin of the subfamily

100%

Sole F., Smith T., Tabuce R., Marandat B.

Acta Palaeontologica Polonica

|

2015

|

tom 60

|

nr 3

Here we describe and illustrate specimens of hyaenodont mammals from two early Eocene localities of Southern France: Fournes (Minervois) and Fordones (Corbieres). Some of these specimens were previously described as cf. Hyracolestes sp. (Cimolesta, Sarcodontidae), a taxon only known from Asia, but new arguments allow their referring to the small proviverrine hyaenodont Parvagula palulae which was previously only recorded in Palette (Provence). The material notably includes the oldest p4 ever recorded for the European endemic subfamily Proviverrinae. This new material shows that, by the beginning of the early Eocene, proviverrines already displayed their typical combination of dental features characterized by the presence of a large paraconid and entoconid on p4. The comparison between the earliest European proviverrines and sinopines (a mostly North American radiation) supports the divergence of the two subfamilies by this time. Moreover, the early proviverrines are morphologically similar to the African hyaenodont Tinerhodon (late Paleo-cene). Consequently, the history of the European proviverrines is likely rooted in Africa. Finally, the new specimens support a similar age for the localities of Palette and Fordones, and a younger age for Fournes. Due to the ages of these localities Parvagula palulae must be regarded as the oldest proviverrine.

2

Dental and tarsal morphology of the European Paleocene-Eocene 'condylarth' mammal Microhyus

100%

Tabuce R., Antunes M. T., Smith R., Smith T.

Acta Palaeontologica Polonica

|

2006

|

tom 51

|

nr 1

New dental and postcranial remains of the alleged louisinine hyopsodontid “condylarth” Microhyus from the European Paleocene/Eocene transition are described, and prompt a reevaluation of the genus. New specimens belonging to Microhyus musculus from Dormaal (MP7, Belgium) provide the first evidence of the lower dentition of the type species. We describe M. musculus? from Pourcy (MP7, France) and cf. Microhyussp. from Berru (MP6a, France). A rich original assemblage of M. reisi from Silveirinha (MP7, Portugal) allows a detailed description of the morphological dental variation within that species. Well−preserved astragali and calcanei from Silveirinha can be confidently attributed to Microhyus reisi. Functional analysis of these elements suggests that Microhyus was a terrestrial mammal capable of rapid running or jumping. The pedal morphology of Microhyus is very similar to that of Paschatherium. These louisinines share some derived characters with the hyopsodontids Apheliscus and Haplomylus (e.g., the occurrence of a cotylar fossa on the astragalus) but they differ from Hyopsodus. Therefore, in view of the pedal morphology alone, the hyopsodontids may be polyphyletic. Given the dental similarities between Microhyus and the early representatives of the order Macroscelidea, we compared the tarsal morphology of louisinines with that of modern macroscelidids (Paleogene tarsal remains are currently unknown for this group). Macroscelidids and louisinines present some similarities in their astragalar morphology; however, the macroscelidid astragalus appears to be too specialized to be compared with that of Microhyus and Paschatherium.

3

A eutherian mammal in the latest Cretaceous of Vitrolles, Southern France

100%

Tabuce R., Vianey-Liaud M., Garcia G.

Acta Palaeontologica Polonica

|

2004

|

tom 49

|

nr 3

In Europe, the fossil record of the eutherian mammals is very scanty for the Late Cretaceous, as only two genera, documented by isolated teeth, are presently recorded in France and in Spain. Both genera, Labes and Lainodon, are considered to be representatives of the “zhelestids”, a paraphyletic unit regarded as being at the origin of Cenozoic ungulates within the Ungulatomorpha clade. We here describe Valentinella vitrollense gen. et sp. nov. from Vitrolles la Plaine (Maastrichtian, southern France). This species, represented by fragmentary remains of lower and upper dentitions, is tentatively assigned to the “zhelestids” according to the hypoconulid−entoconid twinning and the antero−posteriorly short trigonid on m1–3. The occlusal surfaces are obliterated by dental attrition, but Valentinella could be an evolved “zhelestid”, more derived than Labes and Lainodon by its fully compressed trigonid. Valentinella is similar to Gallolestes by other derived characters such as a crushing specialization of the teeth, associated with a probably molariform p4 (or dp4) and slightly reduced m3. The enamel microstructure, showing a radial prismatic pattern combined with a reduced interprismatic matrix, in which cristallites are oriented at about 45° to the prisms axes, appears compatible with the ancestral morphotype for all ungulates; although no synapomorphy can be proposed for the ungulatomorphs.

Ograniczanie wyników

3 Acta Palaeontologica Polonica

3 Tabuce R.

2 Smith T.

1 Antunes M. T.

1 Garcia G.

1 Marandat B.

1 Smith R.

1 Sole F.

1 Vianey-Liaud M.

1 2015

1 2006

1 2004

New dental elements of the oldest proviverrine mammal from the early Eocene of Southern France support possible African origin of the subfamily

Dental and tarsal morphology of the European Paleocene-Eocene 'condylarth' mammal Microhyus

A eutherian mammal in the latest Cretaceous of Vitrolles, Southern France