Dental eruption and growth in Hyracoidea (Mammalia, Afrotheria)

We investigated dental homologies, development, and growth in living and fossil hyracoids, and tested if hyracoids and other mammals show correlations between eruption patterns, gestation time, and age at maturity. Unlike living species, fossil hyracoids simultaneously possess replaced P1 and canine teeth. Fossil species also have shorter crowns, an upper and lower I3 locus, an upper I2, and a hypoconulid on m3. Prenatal specimens of the living $\textit{Procavia capensis}$ and $\textit{Heterohyrax brucei}$ show up to three tooth buds posterior to upper dI1 and anterior to the seven upper cheek teeth that consistently erupt; these include an anterior premolar but not a canine. Most lower cheek teeth finish eruption during growth in hyracoids, not after growth as in most other afrotherians. All hyracoids show the m1 at (lower) or near (upper) the beginning of eruption of permanent teeth; M3/m3 is the last permanent tooth to erupt. The living P. capensis erupts most lower antemolar loci before m2. In contrast, fossil hyraxes erupt lower antemolars after m2. While the early eruption of antemolars correlates with increased gestation time and age at maturity in primates and $\textit{Tupaia}$ (i.e., "Schultz's Rule"), and while modern hyraxes resemble some anthropoid primates in exhibiting long gestation and eruption of antemolars at or before molars, eruption patterns do not significantly co-vary with either life history parameter among afrotherians sampled so far. However, we do observe a shift in eruption timing and crown height in $\textit{Procavia}$ relative to fossil hyracoids, mirroring observations recently made for other ungulate-grade mammals

New remains of Chambius kasserinensis from the Eocene of Tunisia and evaluation of proposed affinities for Macroscelidea (Mammalia, Afrotheria)

International audienceChambius kasserinensis from the late Early or early Middle Eocene Chambi locality, central Tunisia, is undoubtedly the oldest known macroscelidid and possibly the basalmost representative of the order Macroscelidea. Hence, since its discovery in 1986, Chambius has played a key role in analyses focusing on afrotherian and eutherian phylogeny; for instance, as early as 1995, Butler’s review of fossil macroscelideans highlighted the central position of Chambius in the origin of the order. Despite this, Chambius remained poorly known until recently. Here based on new mandibular fragments, well-preserved upper molars and CT scan analysis of the holotype maxilla, Chambius is revised. Its dentition is first described in detail, providing a precise characterization of the genus. Chambius is notably defined by a submolariform P4 with a three-cusped talonid, a reduced talonid on M2, and a prominent metaconule on M1−2. Interestingly, the two transverse lophs of the upper molars are basically formed by preconulecristae, evoking the recently defined peculiar bilophodonty of paenungulates. Comparisons with other Paleogene and modern macroscelidids, European Louisinidae, and North American Apheliscidae are also made, allowing the various hypotheses about the origin and early evolution of macroscelidids to be reviewed

A mandible of the hyracoid mammal Titanohyrax andrewsi in the collections of the Muséum National d'Histoire Naturelle, Paris (France) with a reassessment of the species

International audienceAn unpublished mandible of the large hyracoid Titanohyrax andrewsi from the early Oligocene Jebel Qatrani Formation, Fayum Depression, Egypt is described. This specimen has a twofold importance. Firstly, it opens an unexpected window on early paleontological research in the Fayum because it was discovered as early as 1904 by the French paleontologist René Fourtau during an expedition to the Fayum organized by the Muséum National d’Histoire Naturelle, Paris (MNHN). This expedition has remarkably never been mentioned in the literature. Secondly, the mandible documents the best-preserved specimen of T. andrewsi, permitting a revision of one of the very rare Paleogene hyracoids. Interestingly, the new mandible was discovered two years before the first report of the species by Charles W. Andrews. The hypodigm of T. andrewsi is reviewed and the dentition as a whole is compared indetail, notably with other Titanohyrax species from the Fayum. The validity of the large Titanohyrax “schlosseri” species is discussed, but a pronounced sexual size dimorphism for T. andrewsi is favoured

3D model related to the publication: Filling a gap in the proboscidean fossil record: a new genus from the Lutetian of Senegal

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3D models related to the publication: European mammal turnover driven by a global rapid warming event preceding the Paleocene-Eocene Thermal Maximum

International audienceThis contribution contains the 3D models described and figured in the following publication: Tabuce R., Marandat B., Adnet S., Gernelle K., Girard F., Marivaux L., Solé F., Schnyder J., Steurbaut E., Storme J.-Y., Vianey-Liaud M., Yans J. (2025). European mammal turnover driven by a global rapid warming event preceding the Paleocene-Eocene Thermal Maximum. PNA

De l'ombre aux Lumières et réciproquement : redécouverte du crâne de Procavia capensis (Pallas, 1766) (Hyracoidea, Mammalia) décrit en 1767 par Daubenton dans l' Histoire naturelle

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Mammifères du paléogène ancien d'Afrique du Nord occidentale (systématique, paléobiographie et apport à la phylogénie des "ordres endémiques africains")

MONTPELLIER-BU Sciences (341722106) / SudocSudocFranceF

Révision des faunes de mammifères de la fin de l’Éocène inférieur de Mas de Gimel et de Naples (Montpellier, sud de la France) et description d’un nouveau rongeur théridomorphe

Les sites européens ayant livré des mammifères terrestres datés de la fin de l’Yprésien sont principalement localisés dans le Bassin de Paris. En Europe méridionale (France et Espagne), quelques localités sont également connues, mais toutes n’ont livré que des faunes pauvres, composées de seulement quelques taxons, à l’exception de la localité de Mas de Gimel (ville de Montpellier, Hérault, France), longtemps considérée comme la faune de référence de la fin de l’Yprésien en Europe méridionale. Curieusement, seuls les rongeurs, les artiodactyles et les métathériens de cette localité-clé ont été étudiés en détail depuis les années 1960. Sur la base de la collection originale conservée à l’Université de Montpellier, nous révisons l’ensemble des taxons de mammifères, ce qui nous amène à identifier 38 espèces parmi 12 ordres. Nous étudions également les localités voisines et contemporaines de Naples et Naples 2, où nous identifions 23 espèces parmi 10 ordres. Parmi les espèces identifiées dans les trois localités, nous décrivons le nouveau rongeur théridomorphe Hartenbergeromys pailladensis n. sp., caractérisé par de nombreuses crêtes fines et hautes sur les molaires supérieures et inférieures. Comparé aux quatre niveaux de référence MP (Mammal Paleogene) pour l’Éocène inférieur européen (MP7, MP8+9, MP10a et le possible ‘MP10b’), l’assemblage faunique de Mas de Gimel et de Naples est attribué au MP10a, et représente une référence européenne majeure pour cette période. Ce travail renforce l’hypothèse de l’homogénéité des faunes mammaliennes du Nord- et du Sud-Ouest européen durant l’Yprésien récent.European terrestrial mammal sites dated from the late Ypresian are predominantly known from the Paris Basin. In Southern Europe (France and Spain), some localities are also known, but all have only yielded small faunas, composed by few taxa. An exception is the rich locality of Mas de Gimel (city of Montpellier, Hérault, France), which has long been considered the reference fauna of the late Ypresian in Southern Europe. Curiously however, only the rodents, artiodactyls and metatherians from this key locality have been studied in detail since the 1960s. Here, based on the original collection housed in the University of Montpellier, we revise the entire mammal taxa, which leads us to identify 38 species among 12 orders. We also study the close and co-eval localities of Naples and Naples 2, where we identify 23 species among 10 orders. Among the species identified from the three localities, we describe the new theridomorph rodent Hartenbergeromys pailladensis n. sp., characterized by numerous thin high extra ridges on upper and lower molars. Compared with the four standard MP (Mammal Paleogene) reference-levels for the European Early Eocene (MP7, MP8+9, MP10a, and the putative ‘MP10b’), the faunal assemblage from Mas de Gimel and Naples is attributed to the MP10a, representing a major European reference for this period. This study also supports the idea that, during the late Ypresian, the mammal faunas from North- and Southwestern Europe are quite homogeneous.</p