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International audience; Hypolophin ‘dasyatids’ are a common group of large stingrays today frequenting the Indo-Pacific inshores. Being often harvested in their restricted area, few are known about their biology and their evolutionary history despite a very peculiar dental pattern making it easy to track their fossil record. An abundant material consisting of isolated teeth from Late Bartonian (38–40 Ma) lagoonal deposits of Djebel el Kébar, Tunisia, allows to describe a new stingray, Pastinachus kebarensis nov. sp. This taxon represents the oldest occurrence for this genus but also the oldest fossil record for hypolophins. A dental comparison of thesefossils with 3D rendered models of fresh specimens testifies that early hypolophin representatives had already a strongly arcuate and bulbous upper jaw, interlocking with a broad and elongated tooth plate on the lower jaw. This new fossil and its fossil relatives (here updated), indicate a pre-Bartonian origination for hypolophins in western Neotethys, and reveal a rapid and widespread colonization of the proto-Mediterranean Sea, western Atlantic and Indo-Pacific coasts during the late Paleogene–early Neogene. Finally, it is worth noting that early hypolophin representatives seemingly entered freshwater habitats occasionally as modern cowtail stingrays do.

International audience; Among the Afro-Arabian Palaeogene chiropterans, philisids were the most common and diversified members. ThePhilisidae are considered as an extinct primitive group of Vespertilionoidea, a well-diversified superfamily that todayincludes Natalidae, Molossidae and Vespertilionidae. However, the position of Philisidae within this superfamily has neverbeen clearly established. These bats are characterized by a very distinctive dental morphology, and include somerepresentatives that were among the largest bats to be known. Here we describe new dental remains attributable to philisidsfrom the EarlyMiddle Eocene of Chambi, Tunisia and Gour Lazib area, Algeria. These fossils allow us to reconsider thedental morphology of the oldest philisids: Dizzya exsultans Sige, 1991 and Witwatia sigei Ravel, 2012. We haveundertaken a cladistic assessment of the dental evidence (47 dental and mandible characters) to clarify the phylogeneticrelationships within Philisidae, and its position within Vespertilionoidea, in order to highlight the origin, historicalbiogeography and patterns of dispersion of the most diversified extant bat group. The specialized dental morphology ofphilisids implies particular occlusion seen in the three-dimensional reconstructions of teeth of Witwatia sigei and Dizzyaexsultans. The peculiar morpho-functional anatomy of the teeth and the large size of these bats were well adapted to anopportunistic diet, and probably contributed to the early success of the family in North Africa.

International audience; We present and describe new fossils from the Eocene North African localities of Chambi (Tunisia; late Ypresian or early Lutetian) and Bir el Ater (Algeria; latest Bartonian or earliest Priabonian). The specimens from Chambi allow recognizing two recently described hyainailourines: Furodon crocheti and Parvavorodon gheerbranti; these taxa were previously known from the Gour Lazib area (Algeria; late Ypresian or early Lutetian). The new material from Tunisia includes a fragmentary dentary of Parvavorodon that substantially supports the hyainailourine status of this genus and represents the oldest dentary fragment presently known for a juvenile of Hyaenodonta in Africa. The presence of Furodon and Parvavorodon in Chambi strengthens support for the hypothesis of contemporaneity of the Eocene Gour Lazib and Chambi mammal-bearing localities. In addition, the find of a typical teratodontine fourth premolar in Chambi testifies to the presence of a small representative of this group. The fossil record in Bir el Ater is scarcer than in Chambi. However, we recognize specimens attributable to a hyainailourine and a teratodontine. The latter is referred as Masrasector cf. ligabuei, and is the oldest record for this genus. We tentatively identify a modification of the hyaenodont fauna in the Maghreb after the “Early Eocene Climatic Optimum” (EECO). This faunal change might be related to the decrease of the global temperature after the EECO event. It appears contemporaneous of a drastic replacement in the composition of the mammal faunas in Africa. Finally, the end of the Eocene (Priabonian) shows an increase in the subfamilial richness amongst hyaenodonts.

International audience; Based on fossil discoveries and phylogenetic studies, an Eocene Asian origin for hystricognathous rodents and anthropoid primates has gained strong support in recent years. The two groups then invaded both Africa and South America, which promoted their evolutionary success. However, the fossil record has so far failed to constrain the nature and precise timing of these pivotal dispersal events. In Africa, given the apparent absence of hystricognaths and anthropoids in early to early middle Eocene localities, it is suggested that these mammal groups dispersed from Asia to Africa sometime during the middle Eocene. In this paper, we report the discovery of several isolated teeth of a rodent from a new vertebrate locality situated in central Tunisia (Djebel el Kébar, KEB-1), dating from the late middle Eocene (Bartonian, ~39.5 Myr). These fossils document a diminutive new species of Protophiomys (P. tunisiensis nov. sp.), a basal genus of hystricognathous rodents which is well known from several North African mammalian-bearing localities of the end of the Eocene. The teeth of P. tunisiensis display a suite of anatomical details comparable with those observed in the other species of the genus, but with a lesser degree of development. Such an apparent primitive evolutionary stage is corroborated by the greater antiquity of this Tunisian species. P. tunisiensis nov. sp. is so far the most ancient representative of hystricognaths in Africa. However, it can be expected that hystricognaths were already present on that landmass given the new data on early caviomorphs recently reported from South America (at ~41 Myr). The arrival of hystricognaths in Africa from South Asia certainly predates the depositional period of the Kébar sediments, but perhaps not by much time.

In the past, several destructive earthquakes have occurred in the North African Atlas Mountain ranges located along the Africa–Eurasia plate boundary. Although the region is rich with impressive archaeological sites, including those in modern Tunisia, few comprehensive archaeoseismological studies have been conducted. Historic sources account at least three damaging earthquakes in the Kairouan area in central Tunisia between AD 859 and 1041. Little is known about which faults triggered these earthquakes or the size of these events. The water supply of the city of Kairouan depended on a 32-km-long aqueduct with a large bridge (now partially collapsed) at the confluence of the de Mouta and Cherichira rivers. The original bridge of Roman construction was retrofitted twice during the Aghlabid period (AD 800–903) and probably in AD 995 during the Fatimid period. The ruined section of the bridge shows damage which might be related to the AD 859 earthquake shaking. Here, we present a detailed study of the history, the status and the damage of the Cherichira aqueduct bridge using previous historic accounts and written works, a 3D laser scan model, local geological and seismological characteristics, and include results of radiocarbon dating and a timeline of events. In addition to earthquake ground motions, we consider severe flash floods on the bridge as a potential cause of the damage. We estimate the severity of such flash floods and develop a model with 18 earthquake scenarios on local reverse and strike-slip faults with magnitudes between MW 6.1 and 7.2. While a few damage patterns might be indicative of flooding, most damage can be attributed to earthquakes. It is highly probable that the earthquake in AD 859 caused enough damage to the Aghlabid bridge to render it dysfunctional; however, to resolve the question of whether another earthquake in AD 911 or 1041 caused the complete destruction of the previously retrofitted aqueduct by the Fatimids requires dating of additional sections of the bridge., Universität zu Köln (1017)

Anthracotheres dispersed from Asia toward Africa at least three times: at the Eocene/Oligocene transition, during the early Miocene and later during the Miocene. Those dispersals are important datum events for African Tertiary biochronology. New fossil remains of early Libycosaurus, the genus implicated in the late Miocene dispersal, are described from a new Tunisian locality of the Kasserine area. The new fossils enhance the hypodigm of Libycosaurus algeriensis and increase the resolution of the phylogenetic position of this species using cladistics analysis. The inclusion of the genus Libycosaurus within the well-described Merycopotamus lineage allows us to constrain its dispersal time. Dispersal of this anthracothere from the Indian sub-continent to Africa was probably facilitated by sea level decrease during the early Tortonian, just preceding the Hipparion dispersal event. This new age estimation refines the resolution of the succession of late Miocene deposits in Maghreb and frames the date of the onset of the Sahara.

La façade orientale de la Tunisie correspond à un domaine margino-littoral jalonné par des sebkhas et des lagunes côtières dont celle de Tunis. Cette dernière, située dans la partie septentrionale de cette façade, correspond à une ancienne baie qui a été largement ouverte sur le golfe de Tunis il y a 190 000 ans BP environ. Actuellement, la lagune de Tunis est séparée de la mer Méditerranée par un étroit cordon littoral sableux qui s’étend de l’embouchure de l’oued Miliane aux ports puniques de Carthage. Ce cordon est essentiellement alimenté par les apports des oueds Medjerda et Miliane ainsi que les produits d’altération de la falaise de Sidi Bou Saïd. L’analyse hydrodynamique montre que l’alimentation de la lagune en eaux marines se fait principalement par la passe de Kheireddine au Nord et celle de Radès au Sud. Par ailleurs, cette dernière reçoit aussi les eaux pluviales de petits oueds tels que O. El Grich, et O. El Gsab. De ce fait, les apports liquides et solides sont peu importants et le taux de comblement est faible. Ce travail s’intègre dans un axe de recherche qui traite des interactions entre la faune et son environnement lors des variations climatiques quaternaires. En effet, une carotte sédimentaire longue de 55 mètres, prélevée dans les dépôts alluviaux de la bordure nord-est de la lagune, a fait l’objet d’un échantillonnage serré. Le matériel prélevé a servi à des études sédimentologiques, minéralogiques et paléontologiques afin d’identifier les principales conditions de mise en place de cette zone humide, de suivre la répartition temporelle du stock sédimentaire et de reconstituer son évolution paléoenvironnementale. Les analyses sédimentologiques révèlent une sédimentation marine, constituée de silts argileux vaseux à la base témoignant d’un environnement de dépôt relativement calme, auquel succède un milieu de plus haute énergie, ayant conduit à une sédimentation sableuse et sablo-silteuse. Minéralogiquement ces sédiments sont constitués essentiellement par de la calcite, du quartz et de l’aragonite, accompagnés par de faibles teneurs en calcite magnésienne, dolomite et feldspath. Le cortège des minéraux argileux de la lagune de Tunis est formé de smectite, d’illite, de kaolinite et de chlorite. La répartition de ces minéraux le long de la colonne stratigraphique reflète la nature et l’importance des apports détritiques sous l’influence d’un climat essentiellement chaud et humide avec probablement alternance de saisons sèches et humides. En outre, les associations faunistiques (coraux, ostracodes et foraminifères benthiques) ont permis de suivre l’évolution du milieu de dépôt. Il s’agit d’un environnement franchement marin circalittoral à infralittoral peu ouvert et peu profond évoluant vers une lagune ouverte. La datation U-Th des coraux de l’espèce Balanophyllia regia, extraits à différentes profondeurs de la colonne stratigraphique a révélé un âge compris entre 165 et 205 ka, soit le Pléistocène moyen pour les sédiments du premier milieu, alors que le deuxième est rapporté à l’Holocène-actuel. Cette évolution est en rapport avec l’importance des apports détritiques des deux oueds de Medjerda et Meliane et les variations eustatiques du niveau marin au cours du Quaternaire.

International audience; Bulk sampling of an indurated glauconic sandstone horizon from Djebel el Kébar, Central Tunisia, yielded a moderately diversified assemblage of elasmobranchs (sharks and rays), dating from the late Middle Eocene (mid Bartonian). Here, 10 new taxa (nine new species and three new genera) are described among a total diversity of 33 species. These new taxa highlight the rise of mid-large predator lineages of modern nearshore seas and fill a substantial gap in the sporadic fossil record of the late Middle Eocene. Comparisons of this assemblage with other Middle-Late Eocene faunas from the Tethys seaway indicate that this Tunisian fauna shares more similarities with Late Eocene than with early Middle Eocene assemblages. This suggests that the major shift observed in tropical elasmobranch communities from the Late Eocene, with for instance the appearance of large Carcharhinids replacing Lamniforms, began during the late Middle Eocene. Such a biotic shift could be linked to the warm conditions recorded ca. 41 Ma, known as the Middle Eocene Climatic Optimum (MECO), which was characterized by a short temperature increase of all marine waters.

International audience; A post-Priabonian fluviatile debris-flows in Mabrouk (MBK), Djebel Chambi – Tunisia, have yielded a surprisingly rich assemblage of reworked marine elasmobranchs (23 taxa of sharks and rays). By comparison with their sub-coeval counterparts from northeastern Africa, this assemblage suggests an age ranging from the latest Priabonian up to the earliest Rupelian for the close marine deposit from where they were likely reworked. Moreover, it highlights the widespread east-west distribution of sharks and rays along North African coasts, a distribution that reflects the existence of roughly similar tropical environmental conditions in northern latitudes of Africa at that time. This discovery indicates that the Neotethysian elasmobranch communities remained particularly well diversified around the global cooling recorded at the Eocene/Oligocene transition.

International audience; The Hyracoidea was a successful mammalian order in Africa from the early Eocene to the mid-Miocene. Through the Eocene/Oligocene, hyracoids represented the dominant 'ungulate' group in terrestrial ecosystems. Among them, the genus Titanohyrax embraces very large species as well as a small one, T. tantulus, only known from the ?early/middle Eocene of Chambi, Tunisia. Recently, the generic affinity of this species has been disputed, implying a latest Eocene origin for Titanohyrax. Testing the competing hypotheses requires new data as most species of Titanohyrax are documented by few specimens. Based on new fossils from Chambi and CT scan analysis of the holotype, we revised T. tantulus. A complete skull from the coeval locality Glib Zegdou, Algeria, is also discussed. This analysis reveals that the holotype bears a part of dP3-4 and M1-2 rather than dP2-M1 as it was proposed. More importantly, derived dental characters, including a small compressed hypocone on P2-M3 and highly molarized P3-4 with a W-shaped ectoloph, are distinctive features of Titanohyracidae. Enamel microstructure also indicates affinities with the titanohyracids Antilohyrax and Afrohyrax. Titanohyrax tantulus and Antilohyrax also share a tall, narrow and vertically oriented supraoccipital and no diastemata between the anterior teeth. Moreover, the lack of postorbital bar, a well-developed metastylid on p3-m3, and broad spatulate lower incisors, that lacked tines or serrations, are diagnostic characters of Titanohyrax. As a result, there is no apparent reason to question the generic affinity of T. tantulus. However, the latter differs substantially from the other species of the genus, in harboring a suite of primitive characters: lower crowned cheek teeth, absence of mesostyle on P1-2, less labially expanded mesostyle and parastyle on P4-M3, more labially positioned paracone and metacone, blunt parastyle and mesostyle, longer preprotocrista and prehypocrista, and presence of a paraconular swelling on molars. Titanohyrax tantulus finally differs from late Eocene titanohyracids (Antilohyrax and Titanohyrax sp.) in having sharp supraorbital ridge and extensive sagittal crest, certainly also primitive cranial characters. To conclude, T. tantulus represents an early offshoot of the titanohyracids; this family thus testifies to the longest fossil record among hyracoids. It only disappeared during the early Miocene, likely due to competition with artiodactyls and perissodactyls. * Speaker

The Late Early-to-Early Middle Eocene Zegdoumyidae are the oldest representatives of the order Rodentia to be known in Africa thus far. Despite the fragmentary nature of their fossil record, these early African rodents have been central in discussions surrounding the early evolutionary history of the Anomaluroidea clade (the living forms of which are the ‘scaly-tailed squirrels’, i.e. Anomaluridae). Here, we describe new dental remains attributable to Zegdoumys sbeitlai, a zegdoumyid from Tunisia (Djebel Chambi, CBI-1) dated at ca 50–45 Ma. The original material referred to this taxon was limited to four teeth documenting few dental loci. The new gathered material comprises practically all dental loci (except P4), thereby allowing a better description and characterization of this taxon. This Tunisian species is clearly distinct from its roughly coeval Algerian counterpart (Z. lavocati) or from the younger species recorded from Namibia (Z. namibiensis). We investigated the phylogenetic positions of Z. sbeitlai and the Zegdoumyidae in a high-level rodent phylogeny with a cladistic assessment of the dental evidence. Our results show that zegdoumyids represent the earliest offshoots (pectinately arranged) of a large clade that also encompasses the more advanced Eocene anomaluroids (here named Nementchamyidae), the Miocene Nonanomaluridae, and the stem and crown Anomaluridae. In this phylogenetic context, the species of Zegdoumys are the basalmost members of this large Anomaluroidea clade. Zegdoumyid taxa are therefore the oldest stem anomaluroid candidates, a statement which strengthens support for the hypothesis of the great antiquity of the Anomaluroidea clade in Africa. From a historical biogeography perspective, this assumption suggests that anomaluroids invaded Asia from Afro-Arabia sometime during the Middle Eocene, a dispersal event which was likely concomitant but opposite to the dispersals envisaged for the hystricognathous rodents and anthropoid primates from Asia to Afro-Arabia.

The palladium-catalysed direct arylation using bromofluorenes and heteroaromatics as the coupling partners proceeded in moderate to high yields using only 0.1–0.5 mol% Pd(OAc)2 or 1 mol% PdCl(C3H5)(dppb) as the catalyst and KOAc as the base. A wide variety of heteroarenes have been successfully employed, allowing their properties to be easily tuned. From 2,7-dibromofluorene, successive arylations allow the introduction of two different heteroarenes at carbons C2 and C7.

International audience; We report the discovery of three isolated primate petrosal fragments from the fossiliferous locality ofChambi (Tunisia), a primate-bearing locality dating from the late early to the early middle Eocene. Thesefossils display a suite of anatomical characteristics otherwise found only in strepsirhines, and as suchmight be attributed either to Djebelemur or/and cf. Algeripithecus, the two diminutive stem strepsirhineprimates recorded from this locality. Although damaged, the petrosals provide substantial informationregarding the ear anatomy of these advanced stem strepsirhines (or pre-tooth-combed primates),notably the patterns of the pathway of the arterial blood supply. Using mCT-scanning techniques anddigital segmentation of the structures, we show that the transpromontorial and stapedial branches of theinternal carotid artery (ICA) were present (presence of bony tubes), but seemingly too small to supplyenough blood to the cranium alone. This suggests that the ICA was not the main cranial blood supply instem strepsirhines, but that the pharyngeal or vertebral artery primitively ensured a great part of thisrole instead, an arterial pattern that is reminiscent of modern cheirogaleid, lepilemurid lemuriforms andlorisiforms. This could explain parallel loss of the ICA functionality among these families. Specificmeasurements made on the cochlea indicate that the small strepsirhine primate(s) from Chambi was(were) highly sensitive to high frequencies and poorly sensitive to low frequencies. Finally, variance fromorthogonality of the plane of the semicircular canals (SCs) calculated on one petrosal (CBI-1-569) suggeststhat Djebelemur or cf. Algeripithecus likely moved (at least its head) in a way similar to that ofmodern mouse lemurs.

This study focuses on new fossil faunas of bats discovered in North Africa following several field campaigns. The fossiliferous localities include those from the Early to Middle Eocene of Tunisia (Chambi) and Algeria (Glib Zegdou). Systematic and cladistic analyses carried out on the fossil material, primarily including isolated teeth, allow us to highlight the modalities of the radiation of the first modern microbats. These new faunas include eight well-identified new taxa belonging to five modern families: one Necromantidae (?Necromantis fragmentum Ravel, n. sp.), two Hipposideridae Miller, 1907 (?Palaeophyllophora tunisiensis Ravel, n. sp. and Hipposideros [Pseudorhinolophus] africanum Ravel, n. sp.), three Emballonuridae Gervais in de Castelnau, 1855 (Vespertiliavus kasserinensis Ravel, n. sp., ?Vespertiliavus aenigma Ravel, n. sp., and Pseudovespertiliavus parva Ravel n. gen., n. sp.), one Nycteridae (Khoufechia gunnelli Ravel n. gen., n. sp.) and an undetermined Vespertilionidae. Two other taxa are identified (Chambinycteris pusilli Ravel n. gen., n. sp. and Drakonycteris glibzegdouensis Ravel n. gen., n. sp.), but they show an original dental pattern which precludes a family attribution. Two cladistic analyses allow to clarify the phylogenetic position of the best documented taxa. The results highlight for Hipposideridae and Emballonuridae chiropterans a major dispersal axis from North Africa towards South Europe during the Middle Eocene.

La région de Kasserine, en Tunisie centrale, est depuis très longtemps considérée par de nombreux auteurs comme une terre émergée formant une île ou un archipel, depuis le Crétacé terminal jusqu’au Miocène moyen. Dans les années 1980, des dépôts continentaux y ont alors été découverts et datés de l’Eocène. Jusqu’à aujourd’hui, aucun dépôt marin plus vieux que le Miocène moyen n’était donc connu en Tunisie centrale et les seuls faciès marins attribués à l’Eocène, étaient ceux des bassins phosphatés formés en périphérie de la zone émergée. C’est dans la région du Djebel el Kébar, située sur la bordure est de la zone de Kasserine, qu’une étude détaillée des dépôts de la période Eocène moyen-Miocène a été menée. Dans la série étudiée, quatre discontinuités majeures se corrèlent sur l’ensemble du site. Entre ces discontinuités, se succèdent trois ensembles sédimentaires : carbonaté glauconieux et argileux (I), carbonate (II), sablo-conglomératique et argilo-sableux (III). Les résultats paléontologiques et biostratigraphiques Un important gisement à faune marine et continentale a été découvert au Djebel el Kébar dans les dépôts glauconitiques marins du premier ensemble sédimentaire (I). La faune, très riche, est alors constituée de nombreuses formes marines (sélaciens, raies, siréniens, etc.) et continentales (rongeurs, hyracoïdes et primate). Les datations inédites indiquent un âge bartonien, pour ces dépôts. Les résultats sédimentologiques Treize faciès ont été identifiés et cartographiés grâce à des conditions d’affleurement exceptionnelles au Djebel el Kébar. Les paléo-environnements ont été reconstitués et leur succession montrent le passage d’un milieu de plate-forme carbonatée très peu profonde dominée par la houle et influencée par les tempêtes et la marée, à un système sablo-conglomératique et argileux, fluviatile et d’embouchure estuarienne. L’évolution tectono-sédimentaire et séquentielle Un découpage séquentiel a été proposé, dans lequel, de part et d’autre de discontinuités essentiellement d’origine tectonique, trois séquences dont les durées (> 3 Ma), compatibles avec le second ordre de Vail et al. [1991], sont très partiellement préservées. Dans ces séquences, l’essentiel de la série étudiée se met en place dans les cortèges transgressifs et les prismes de hauts niveaux marins. Les zones fossilifères semblent alors associées à plusieurs épisodes de condensation, intervenant au sein d’un cortège transgressif d’un cycle de second ordre. Conclusion Le premier résultat inédit de ce travail a été de mettre évidence et de dater des dépôts marins plus anciens que le Miocène moyen au Djebel el Kébar, en Tunisie centrale. La zone étudiée n’est donc pas dans la partie émergée de la zone de Kasserine à l’Eocène. Entre le Bartonien et le Miocène inférieur, les faciès marins évoluent au sein d’un environnement de plate-forme carbonatée très peu profonde. Un événement majeur (flexuration couplée à une chute eustatique au Miocène) provoquerait ensuite un changement de profil de dépôts, l’arrivée de matériel terrigène grossier et l’installation d’un système sédimentaire fluviatile et d’embouchure sableuse. Enfin l’ensemble de la série sédimentaire enregistre des fluctuations tectono-eustatiques, responsables de plusieurs séquences de second ordre, partiellement préservées.

International audience; A very tiny cuckoo, Chambicuculus pusillus, was recently described after a few fragments of tarsometatarsi from thelate Early/early Middle Eocene of Djebel Chambi, Tunisia. New remains, notably a coracoid, confirm the attribution of this genusto the family Cuculidae. This coracoid shows a very elongate and strap-like processus procoracoideus. This morphological featureis present in some recent or extinct taxa but it is more developed in the family Cuculidae. The characteristics of the coracoid andtarsometatarsi show that Chambicuculus is morphologically more advanced over the other stem cuculids described in Europe andNorth America. Chambicuculus is the oldest Cuculidae known so far.

International audience; The emergent domain known as “Kasserine Island” in central Tunisia, to the West of the North–South Axis, was emerging during the Turonian. This area has undergone several changes during the Cretaceous–Eocene period. In the present study, the compilation of surface and sub-surface data provided new information about the boundaries variations of the emerged domain. The analysis of paleogeographic maps allowed the identification of three distinct stages of evolution. The first stage extents from the Middle Turonian to the Lower Maastrichtian where the emergent domain covers the area extending from Jebels Selloum-Sidi Aich in the West to Jebel Bouhedma in the East. The boundaries of this area coincide with the E–W Kasserine fault to the North, the N–S Lessouda-Boudinar fault in the East and the N 120 el Mech-Souinia flexure at the South. This emersion contemporaneous with a high eustatic level is most likely related to tectonic activity. The extensional tectonic regime that is characterized by a NE–SW minimal horizontal stress, has reactivated border faults with a normal component. The interference of the tilting of these border faults was at the origin of the emergence of this domain. The ascent of the Triassic salt may also have contributed in this uplift.In the second stage, the emerged domain has reached its maximum expansion to the North, the West and the South during the Middle Maastrichtian–Paleocene period. Its northern limit is irregular, while the southern limit coincides with the N120 Gafsa fault and the E–W fault of Jebels Orbata-Bouhedma. The N–S Lessouda-Boudinar fault forms the eastern limit. This expansion is mostly related to the global eustatic fall that is well characterized during this period, and partly to the compressive tectonic activity.The Lower Eocene is characterized by a marine transgression that has interested the northern edge of the Island, where the Ypresian deposits are discordant on older series. This edge was irregular and marked by the Gulf of Sbiba. The eastern, the southern, and the western boundaries kept the same shape as that of the previous stage. The compressive tectonic regime, characterized by a NW–SE maximum horizontal stress, is accentuated. This constraint state has generated NE–SW folds and NW–SE grabens. Some of these structures allowed the accumulation of a thick phosphate deposits at their edges, and continental deposits in the emerged area.During the Middle to Upper Eocene, the emergent area narrowed further at the North. The deposits are transgressive and discordant on older series. The Other limits always coincide with the Gafsa fault, the Jebels Orbata-Bouhedma and Jebels Lessouda-Boudinar faults. This period is characterized by the filling of the Gafsa basin by evaporate deposits before its emergence in the Oligocene. As a result, the southern-central Tunisia emerged as one area.

International audience

International audience; Dental and postcranial remains (an atlas, carpus and metacarpus elements, and a part of the pelvic girdle) of an embrithopod mammal are described from Bir Om Ali, Tunisia, a new late Eocene locality. The enamel microstructure of a tooth fragment found in association shows 'arsinoitheriid radial enamel', an enamel condition which is characteristic of Arsinoitherium (Arsinoitheriidae, Embrithopoda). Although the postcranial elements slightly differ in size and morphology from those of Arsinoitherium zitteli (late Eocene to early Oligocene), we tentatively refer this new Eocene Tunisian material to that genus. These fossils represent the first known embrithopod from the Eocene of Tunisia.

BACKGROUND: Molecular clock estimates of crown strepsirhine origins generally advocate an ancient antiquity for Malagasy lemuriforms and Afro-Asian lorisiforms, near the onset of the Tertiary but most often extending back to the Late Cretaceous. Despite their inferred early origin, the subsequent evolutionary histories of both groups (except for the Malagasy aye-aye lineage) exhibit a vacuum of lineage diversification during most part of the Eocene, followed by a relative acceleration in diversification from the late Middle Eocene. This early evolutionary stasis was tentatively explained by the possibility of unrecorded lineage extinctions during the early Tertiary. However, this prevailing molecular view regarding the ancient origin and early diversification of crown strepsirhines must be viewed with skepticism due to the new but still scarce paleontological evidence gathered in recent years. METHODOLOGICAL/PRINCIPAL FINDINGS: Here, we describe new fossils attributable to Djebelemur martinezi, a≈50 Ma primate from Tunisia (Djebel Chambi). This taxon was originally interpreted as a cercamoniine adapiform based on limited information from its lower dentition. The new fossils provide anatomical evidence demonstrating that Djebelemur was not an adapiform but clearly a distant relative of lemurs, lorises and galagos. Cranial, dental and postcranial remains indicate that this diminutive primate was likely nocturnal, predatory (primarily insectivorous), and engaged in a form of generalized arboreal quadrupedalism with frequent horizontal leaping. Djebelemur did not have an anterior lower dentition as specialized as that characterizing most crown strepsirhines (i.e., tooth-comb), but it clearly exhibited a transformed antemolar pattern representing an early stage of a crown strepsirhine-like adaptation ("pre-tooth-comb"). CONCLUSIONS/SIGNIFICANCE: These new fossil data suggest that the differentiation of the tooth-comb must postdate the djebelemurid divergence, a view which hence constrains the timing of crown strepsirhine origins to the Middle Eocene, and then precludes the existence of unrecorded lineage extinctions of tooth-combed primates during the earliest Tertiary.

International audience; Palaeobotanical material has been collected from the Callovian of Beni Barka, 4 km south of Tataouine (South Tunisia). The fossil plants originate from a limestone formation just below the carbonate bar, that delimits the Beni Oussid member which belongs to the marls and limestones of Tataouine Formation. The floristic composition is marked by the presence of Pteridophytes: Piazopteris branneri (White) Lorch and Coniferophytes: Brachyphyllum trauti Barale et Contini, Pagiophyllum cf. crassifolium Schenk, Araucarites sp., Podozamites sp. This flora was present in a margino-littoral platform situated between the African continent to the south and the South-Tethyan ocean to the north. The autochthony of the locality is demonstrated. Comparisons are made with the floras situated at the northern and southern margins of the Tethys Sea. A sub-tropical climate was present, favouring the development of a ripisilve flora of conifers, with an underwood of ferns.

Sea cows (manatees, dugongs) are the only living marine mammals to feed solely on aquatic plants. Unlike whales or dolphins (Cetacea), the earliest evolutionary history of sirenians is poorly documented, and limited to a few fossils including skulls and skeletons of two genera composing the stem family of Prorastomidae (Prorastomus and Pezosiren). Surprisingly, these fossils come from the Eocene of Jamaica, while stem Hyracoidea and Proboscidea - the putative sister-groups to Sirenia - are recorded in Africa as early as the Late Paleocene. So far, the historical biogeography of early Sirenia has remained obscure given this paradox between phylogeny and fossil record. Here we use X-ray microtomography to investigate a newly discovered sirenian petrosal from the Eocene of Tunisia. This fossil represents the oldest occurrence of sirenians in Africa. The morphology of this petrosal is more primitive than the Jamaican prorastomids’ one, which emphasizes the basal position of this new African taxon within the Sirenia clade. This discovery testifies to the great antiquity of Sirenia in Africa, and therefore supports their African origin. While isotopic analyses previously suggested sirenians had adapted directly to the marine environment, new paleoenvironmental evidence suggests that basal-most sea cows were likely restricted to fresh waters.