Jean Sudre

The anthropoid status of a primate from the late middle Eocene Pondaung Formation (Central Myanmar): Tarsal evidence

Primate dental and postcranial remains from the Eocene Pondaung Formation (Myanmar) have been the subject of considerable confusion since their initial discoveries, and their anthropoid status has been widely debated. We report here a well preserved primate talus discovered in the Segyauk locality near Mogaung that displays derived anatomical features typical of haplorhines, notably anthropoids, and lacks strepsirhine synapomorphies. Linear discriminant and parsimony analyses indicate that the talus from Myanmar is more similar structurally to those of living and extinct anthropoids than to those of adapiforms, and its overall osteological characteristics further point to arboreal quadrupedalism. Regressions of talar dimensions versus body mass in living primates indicate that this foot bone might have belonged to Amphipithecus. This evidence supports hypotheses favoring anthropoid affinities for the large-bodied primates from Pondaung and runs contrary to the hypothesis that Pondaungia and Amphipithecus are strepsirhine adapiforms.

Anthropoid versus strepsirhine status of the African Eocene primates Algeripithecus and Azibius: craniodental evidence.

Recent fossil discoveries have demonstrated that Africa and Asia were epicentres for the origin and/or early diversification of the major living primate lineages, including both anthropoids (monkeys, apes and humans) and crown strepsirhine primates (lemurs, lorises and galagos). Competing hypotheses favouring either an African or Asian origin for anthropoids rank among the most hotly contested issues in paleoprimatology. The Afrocentric model for anthropoid origins rests heavily on the >45 Myr old fossil Algeripithecus minutus from Algeria, which is widely acknowledged to be one of the oldest known anthropoids. However, the phylogenetic position of Algeripithecus with respect to other primates has been tenuous because of the highly fragmentary fossils that have documented this primate until now. Recently recovered and more nearly complete fossils of Algeripithecus and contemporaneous relatives reveal that they are not anthropoids. New data support the idea that Algeripithecus and its sister genus Azibius are the earliest offshoots of an Afro–Arabian strepsirhine clade that embraces extant toothcombed primates and their fossil relatives. Azibius exhibits anatomical evidence for nocturnality. Algeripithecus has a long, thin and forwardly inclined lower canine alveolus, a feature that is entirely compatible with the long and procumbent lower canine included in the toothcomb of crown strepsirhines. These results strengthen an ancient African origin for crown strepsirhines and, in turn, strongly challenge the role of Africa as the ancestral homeland for anthropoids.

Tchad: Découverte d'une faune de mammifères du pliocène inférieur

Abstract In Northern Chad, the site of Kolle in the Djourab erg has yielded a vertebrate fauna including 21 species, 14 of which are Mammals. This fauna provides evidence of a mosaic of environments: fresh-water, woodlands, grasslands. In spite of possible taphonomic or collecting bias, and of some endemicity, this fauna allows us to propose an age in the range 5-4 My.

FIRST ASCERTAINED AFRICAN “CONDYLARTH” MAMMALS (PRIMITIVE UNGULATES: cf. BULBULODENTATA AND cf. PHENACODONTA) FROM THE EARLIEST YPRESIAN OF THE OULED ABDOUN BASIN, MOROCCO

Abstract We report here the discovery of the first well identified “condylarths” from Africa, from the phosphatic beds of Ouled Abdoun Basin, Morocco, of probable early Ypresian age, which have also yielded the oldest known proboscidean. Abdounodus hamdii n. gen., n. sp. and Ocepeia daouiensis, gen. et sp. nov., show closest relationships with Mioclaenidae and Phenacodonta respectively. Both taxa also have resemblances with South American primitive ungulates, especially Abdounodus which resembles kollpaniine mioclaenids in several derived features, mostly related to a similar crushing specialization. However divergent specializations in Abdounodus and kollpaniines strongly suggest their parallelisms, in accordance with their age disparity. Some features of Abdounodus appear to be even original with respect to known mioclaenids. Though Ocepeia shares peculiar derived features with phenacodontids, it is strikingly specialized in its secondarily simplified p4, indicating sister-taxa relationships within Taxeopoda (Phenacodonta, Pantomesaxonia). Moreover, Ocepeia shares a remarkable derived feature with more advanced pantomesaxonian ungulates (Perissodactyla, Hyracoidea, Tethytheria and extinct relatives): the development of an entolophid. This raises the alternative question of their sister-taxa relationships within Taxeopoda and indeed the question of an African origin of Pantomesaxonia, which is congruent with the Paenungulata hypothesis.Though still poorly documented, these new Ouled Abdoun taxa show that early Paleogene African mammal faunas might provide key-data for the problem of the origin and basal phylogeny of main pantomesaxonian ungulate lineages. These fossils show again the importance of the African scene in the early evolution of (modern) eutherians and the poor state of our knowledge there.

NEW REMAINS OF PONDAUNGIMYS ANOMALUROPSIS (RODENTIA, ANOMALUROIDEA) FROM THE LATEST MIDDLE EOCENE PONDAUNG FORMATION OF CENTRAL MYANMAR

Abstract Except for the few specimens previously reported from the late middle Eocene of North Africa (Algeria) and more recently from South Asia (Myanmar), the fossil record of anomaluroid rodents is relatively scarce for the Paleogene Period. In this paper, we describe new material, notably a skull, of the anomaluroid taxon Pondaungimys anomaluropsis Dawson et al., 2003, recently described from the latest middle Eocene Pondaung Formation in Central Myanmar (South Asia). Pondaungimys shows a dental pattern very similar to that of Nementchamys, an anomaluroid rodent previously reported from roughly coeval deposits in Algeria. Although Nementchamys and Pondaungimys have a dental pattern relatively more primitive in some respects than that of Miocene and modern anomalurids, in other respects they show a derived dental complexity that leads us to consider both taxa as the closest outgroups of the Anomaluridae sensu stricto (the true scaly-tailed flying squirrels) within the Anomaluroidea. Pondaungimys clearly demonstrates that the evolutionary history of the anomaluroid rodents is not limited to Africa. The widespread South Asian-North African distribution of the late middle Eocene forms strongly suggests that faunal exchanges between Africa and Asia took place during the Paleogene, a statement supported by other mammalian groups.

A New Eocene Locality in Southern France Sheds Light on the Basal Radiation of Palaeotheriidae (Mammalia, Perissodactyla, Equoidea)

ABSTRACT A new Eocene locality in southern France has yielded a poorly diversified vertebrate fauna but does contain abundant material representing a new species of early equoid, Pachynolophus eulaliensis, sp. nov. Biostratigraphic data for this new locality of Sainte-Eulalie suggest a middle Ypresian age. The new species is the oldest representative of the Palacotheriidae, here including the controversial pachynolophs. The abundant remains of this taxon from a single locality allow the recognition of a high degree of unsuspected variability within this taxon, including sexual dimorphism, thus permitting discussion of the reliability of commonly used characters. A phylogenetic analysis led us to emend the diagnosis of the genus Pachynolophus as well as to suggest the exclusion of ‘Pachynolophus’ hookeri from the genus. This study proposes new hypotheses of relationships among the basal Equoidea and allows us to distinguish the two main groups (Equidae and Palaeotheriidae) earlier in the Eocene, close to the reference level MP8–9. The new material appears to be a fundamental cornerstone in solving the question of the controversial systematics and phylogeny of pachynolophs. It also sheds new light on the temporal and spatial distribution of the initial radiation of European equoids.

A new Palaeocene albulid (Teleostei: Elopomorpha) from the Ouled Abdoun phosphatic basin, Morocco

A new albulid fish, Phosphonatator oxyrhynchus, based on a single large neurocranium, is described from the deposits of the Ouled Abdoun phosphatic basin, Morocco. The matrix of the fossil contains an elasmobranch assemblage indicating a Danian age (with some redeposited Maastrichtian elements). P. oxyrhynchus is characterized notably by its elongated snout and by a reduced patch of teeth on the parasphenoid. Up to now, fossil fishes from the Ouled Abdoun phosphatic basin were mainly known by isolated remains, and the recovery of this specimen should be ranked equal to the recent discovery of important, very well-preserved new material of vertebrates in the Sidi Daoui area.

Découverte du premier squelette presque complet de Rhabdodon priscus (Dinosauria, Ornithopoda) du Maastrichtien inférieur de Provence

Abstract The Vitrolles-Couperigne locality has yielded an almost complete skeleton of Rhabdodon priscus . Until now, this taxon was only represented by sparse and fragmentary remains. The flora and fauna associated to the R. priscus remains are briefly described. The position of the locality in the Late Cretaceous stratigraphy of Provence is discussed on the basis of dinosaur eggshell biostratigraphy. New data concerning some hitherto unknown anatomical features of the R. priscus permit discussion of its systematical position within the dinosaurs.

Nouveaux sites d'âges variés dans les remplissages karstiques du Miocène inférieur de Bouzigues (Hérault, Sud de la France): Partie II: faunes 2 (rongeurs),biochronologie et corrélations

The fossil mammal-bearing site of Bouzigues includes three localities of different ages (Bouzigues 1, 1A and 2) within a radius of 10 m. The rodent faunas are analysed and one of the two new species of Bouzigues 2 is described (Myoglis houlezi nov. sp.). On the basis of the degree of evolution of some mammals and the difference in the faunal composition, an age between that of Bouzigues 1 and that of Serre de Verges is proposed for the two new localities. Therefore, they could be more or less contemporaneous with the Estrepouy level. The heterochrony of the Bouzigues fissure fillings bears evidence of several episodes of emptying and infilling of this paleokarst. The faunas analyse shows, for the considered period, a progressive increase of the forest in a warm climate.

A new early late Oligocene (MP 26) continental vertebrate fauna from Saint-Privat-des-Vieux (Alès Basin, Gard, Southern France)

ABSTRACT This fauna results from the short-time excavation of a restricted fossiliferous level, following the opening of a trench for the installation of a gas conduit. Even if the amount of sediment is limited, the diversity of the fauna approaches that of other contemporaneous localities. Among the 40 vertebrate species, a few are amphibious, and most terrestrial. Among them, biochronological markers like Issiodoromys pauffiensis Vianey-Liaud, 1987 (Rodentia, Theridomyidae) are better defined. This species is compared with the type population of the MP 26 Mammalian Paleogene standardlevel (Mas-de-Pauffié, Lot; early Chattian). In addition, evolutionary grades hitherto unknown are described for several less well represented species: a sciurid rodent Comtia n. gen., a molossid bat (Cuvierimops sp.), a probable talpid, and the hyaenodontid Thereutherium thylacodes Filhol, 1876. The familial assignment of the snake Platyspondylia Rage, 1974 is discussed. The locality yielded the possible earliest shinisaurian lizard. The diversity of this new vertebrate fauna is compared to that of several localities from the same biochronological level (mainly Mas-de-Pauffié, Saint-Menoux, Saint-Henri/Saint-André, Mümliswil-Hardberg and Oensingen 11). The choice of Mas-de-pauffié as the reference-locality for MP 26 is therefore supported.