Les Pistes de Vertébrés du Stormberg Supérieur ("Trias terminal à Rhétien"), ou Quthingien

Si les zones du Stormberg inférieur se sont révélées contenir de nombreuses traces, surtout dans les faciès dits "Molteno moyen et supérieur", représentant apparemment la base du Keuper, il est frappant de voir pratiquement l'ensemble de cette grosse faune "Molteno" disparaître avec la fin de cette période, que nous avons appelée le "Maphutsengien".

Dès les premières zones du Stormberg supérieur, que nous nommons le"Quthingien" la zoocénose et la phytocénose, en même temps que les données d'ensemble manifestées par l'environnement, sont modifiées. Nous ne verrons plus guère de dépôts marécageux à flore riche et variée, parfois même luxuriante. Les fougères elles-mêmes ont disparu. Elles sont remplacées par de maigres plantes, aux feuilles très souvent filiformes qui paraissent témoigner d'un climat continental. Le sol est devenu de plus en plus rouge, avec des variations latérales beaucoup plus accusées. Les fleuves amenant des galets des monts du "Grand Sud" ont tari. La faune va en subir les conséquences. Certaines des espèces se révèleront sautillantes ou coureuses, pour un grand nombre plus légères et pour la quasi-totalité d'apparence carnivore ou entomophages, les phytophages devant se contenter d'un régime ingrat,difficile ou à tout le moins irrégulier,les dépôts le montrent.

C'est dans ces conditions que s'inaugure notre Etage nouveau,quelque peu discordant sur les zones A/5, A/6 ou A/7 du Stormberg inférieur (Maphutsengien). Le Stormberg supérieur (ou Quthingien) commence avec le paléopaysage remarquable dit de Moyeni, que nous allons maintenant étudier, typologiquement, avec ses homologues du même âge. Quelques 38 types d'animaux tous nouveaux vont défiler à nos yeux lors de la zone de base de cet Etage, ou zone B/1.

L'on nous avait proposé d'intituler ce Ile Tome de la série : "La grande Dalle de Moyeni et ses homologues. Paléo-spectacles, scènes et paysages animaux au Lesotho à l'approche du Trias finissant". Nous avons préféré garder le sous-titre plus haut, peut-être plus prosaïque.

Un llle Tome est en préparation : "Les développements ultérieurs et terminaux de la faune du Gondwana".

  

A new Tertiary megadermatid is described from Rackham's Roost Site, a Pliocene limestone cave deposit on Riversleigh Station, northwestern Queensland, Australia. It appears to represent the first Australian record of Megaderma GEOFFROY, 1810, a genus otherwise known from Tertiary African and European taxa and the living Asian species M. spasma (LINNAEUS, 1758) and M. (Lyroderma) lyra PETERS, 1872. Megademza richardsi n. sp. is one of the smallest megademiatids known. It exhibits a mixture of plesiomorphic and autapomorphic features, the latter appearing to exclude it from being ancestral to any living megadermatid. The new species is one of eight megadermatids identified from the Australian fossil record, most of which are referable to Macroderma MILLER, 1906. 

Systematische Zoologie by A. REMANE, V. STORCH, and U. WELSCH.
1986, Edition 3. Cloth and paperbound. Stuttgart and New York : Gustav Fischer Verlag.
xvi + 698 pp. DM 86. (Geb.) & DM 72 (kart.). 

The Middle Eocene Fossillägerstätte of the Geiseltal lignite beds near Halle/S. (German Democratic Republic) is the reference locality of the European land mammal age Geiseltalian and of the Mammalian Paleogene reference levels MP 11 - MP 13. Due to this importance a reinvestigation is given of the lithostratigraphical development of the Geiseltal beds and of their vertebrate sites. The last are genetically related to the southwest border of the Geiseltal depression and the influx of carbonate-rich waters. The geographical distribution and stratigraphical position of the fossiliferous sites depends on subrosive and tectonically controlled distribution of coal seams. The geological factors and the known stratigraphical guide of some mammalian species suggest corrections of the age of some sites. Four of the alltogether five coal bearing phases contain the 35 sites with mammalian remains. By the distribution of the around 69 mammal species are characterized, with 5 faunal steps ranging from MP 11 to MP 14 or over the Geiseltalian up to the Lower Robiacian. Well distant are the faunas of MP 11 and MP 12. Beginning with MP 12 up to MP 13/14, the fossil record is very frequent by 27 sites. This evidence coincides somewhat more with the concept of land mammal ages compared to that of the punctual mammalian reference levels. 

 Detailed anatomical description of arsinoithere cranial remains from the Lower Oligocene, Fayum Depression, Egypt, provides the basic data for a systematic investigation. All cranial and some postcranial features are assessed from a phylogenetic standpoint. Several soft tissue characters are then added to a cladistic analysis based on 54 derived ungulate morphological characters. The resulting phylogenetic hypothesis implies that perissodactyls, sirenians, proboscideans and arsinoitheres constitute a monophyletic unit (5 synapomorphies). However, increasing the tree length by 3 steps reveals a closer association between hyraxes and perissodactyls. Nevertheless, 13 synapomorphies link proboscideans, sirenians and  arsinoitheres to the exclusion of all other ungulates. Form of the sphenopalatine and ethmoid foramina, recurved posttympanic process, absence of a fenestra rotundum in the petrosal, vestigial paroccipital process of the exoccipital and the highly unusual absence of a hypoglossal foramen in the skull, imply a robust sister-group relationship between arsinoitheres and proboscideans. In this analysis artiodactyls share only one derived character with all other ungulates studied. Monophyly of Ungulata, including Artiodactyla, is therefore only weakly supported. It is argued that pedal anatomy of hyraxes is non-homologous with that of Tethytheria. Arsinoitherium should now be classified within Tethytheria, sharing a sister-group relationship with Proboscidea. Hyraxes are excluded, thus refuting the concept of Paenungulata. However, monophyly of the wider concept, Pantomesaxonia, containing hyraxes, perissodactyls, sirenians, proboscideans and now, arsinoitheres, is supported by this study. 

The family Didelphidae is represented by three species in the Sainte-Néboule site, phosphorites of Quercy (lower Oligocene, San Cugat's nivel): Amphiperatherium minutum (Aymard), Amphiperatherium sp. and Peratherium cuvieri (Fischer). Only the first  and  third species are abundant (88 and 97 pieces). This two populations are described. The marsupial fauna of the european lower Oligocene is not recognized in its entirety in this site. 

The rodents from the spanish locality of Can Ponsic 1 bring new data about some rodents species of the beginning of the Upper Miocene in South-West Europe. The criticims made by Mein and Freudenthal about the validity of the species Hispanomys thaleri from Can Llobateres are not justiíied. The study of the anatomy of the skull of Rotundomys from Can Ponsic 1 gives accurate information about the affinity of this genus with Cricetulus, and shows that the hypothesis, according to which Rotundomys is an ancestral form of the Arvicolids, is unlikely. The systematics of Heteroxerus and the phylogeny of the mio-pliocene Muscardinus species are also discussed. The Can Ponsic 1 locality is a little older than Can Llobateres.

  

Carolocoutoia ferigoloi gen. et sp. nov. is the largest of protodidelphid marsupials, known from Middle Paleocene levels at Itaboraí Formation, southeastern Brazil. It differs from other members of this family in having molars with low cusps which are basally inflated, rounded crests without cutting edges, and a thick enamel layer which is wrinkled, specially at the labial half. A comparative analysis among representatives of this family led us to recognize only three genera undoubtely assignable to it:  Protodidelphis PAULA COUTO, 1952, Robertbutleria MARSHALL, 1987, and Carolocoutoia gen. nov. Protodidelphids lack the basic derived features diagnostic of Polydolopimorphian marsupials, while most of its derived features agree with its belonging to the Didelphimorphia. Protodidelphids comprise a specialized clade of opossum-like marsupials adapted to frugivorous or frugivore-omnivorous feeding habits. They differ from other didelphimorphians in having very large, spire-like entoconids, reduced and antero-posteriorly compressed paraconids, absence of stylar cusp C and of para- and metaconules, large stylar cusps B and D which are proximate to each other, short postmetacristae, eccentric protocones, and molars that increase rapidly in size from M/ml to M/m3.
  

The Montredon site has yielded about hundred rhinoceros remains:
- twenty two of them, including 14 carpal and tarsal bones and 6 complete metapodials, belong to
Dicerorhinus schleiermacheri at its second evolutionary stage;
- fifty one remains including a nearby complete but crushed skull, a mandible, 26 isolated cheek-teeth, 10 carpals and tarsals, one metacarpal, are of Aceratherium incisivum, second evolutionary
stage;
- fifteen remains belong to Aceratherium (Alicornops) simorrense (among other an upper molar, 8 carpals and tarsals, one metatarsal);
- six remains are attributed to an undetermined species of what is probably the most recent Prosantorhinus ever found.
The evolution stages of the two first species allow us to date the deposit back to the Upper Vallesian, MN 10 zone; Montredon is one of the youngest sites in which Aceratherium simorrense was found. The four rhino species indicate a swampy forest biotope 

The genus Microstonyx was found only in the north eastern part of Spain : M. antiquus, referable to the
Eppelsheim type, from the pyrenean basins ; M. antiquus, more progresive, from the Vallès Basin : M. major-erymanthius group, from the Teruel-Ademuz Area and from Pieru (Penedès Basin).

  

La faune d'artiodactyles de Ste-Néboule, qui comprend neuf espèces, présente de nombreux
points communs avec les faunes habituellement rattachées au Ludien supérieur, telles celles de La Débruge ou de Montmartre. A l'inverse de ces localités, on ne connaît pourtant, à Ste-Néboule, ni Oxacronae, ni Anoplotheriinae. Parmi les espèces du gisement se trouve une nouvelle espèce du genre Mouillacitherium (M. schlosseri n. sp.), cette forme devant être interprétée comme le dernier représentant du rameau. Nous faisons connaître par ailleurs la presque totalité de la denture du Dacrytherium saturninii, espèce qui était à ce jour très imparfaitement documentée. Ste-Néboule est, d'autre part, la seule localité où l'on peut signaler l'association probable de deux lignées du genre Amphimeryx. Les primates sont peu diversifiés à Ste-Néboule, puisque le groupe est limité au seul genre Adapis. Les genres Microchoerus et Pseudoloris, que l'on sait pourtant être représentés dans des gisements dâge voisin (Microchoerus ornatus à San Cugat de Gavadons et Mormont-Entreroches, Pseudoloris reguanti à San Cugat de Gavadons, Pseudoloris cf. reguanti à Neustadt ; cf. Louis et Sudre 1975) sont absents dans les faunes du Quercy de cette période. 

Le matériel provenant de nouvelles fouilles dans les phosphorites du Quercy, soumis aux divers spécialistes, a conduit à la soutenance de plusieurs thèses d'état: sur les rongeurs (Hartenberger, Vianey-Liaud), les Chiroptères et Insectivores (Sigé), les Artiodactyles (Sudre), les Squamates (Rage) et, en partie, les Chéloniens (De Broin). Chacun dans son domaine, à côté des conclusions d'ordre évolutif, paléogéographique ou paléoécologique, a pu établir des successions stratigraphiques des gisements du Quercy qui se sont révélées largement concordantes. Ainsi la succession des faunes du Quercy est actuellement l'une des mieux établies. Dans ce contexte, les différents spécialistes ont décidé de conjuguer leurs efforts dans l'étude monographique de plusieurs gisements repérés le long de cette échelle, afin de rassembler l'information paléontologique sur des faunes bien précises et de tenter d'obtenir des indications d'ordre taphonomique. 

Description, for the first time, of the skull of Ruscinomys Depéret on the basis of a nearly complete specimen, and description of a new facial part of a Megacricetodon Fahlbusch skull (material from upper Miocene, Spain). New description of the skull (facial part) of " Cricetodon" incertum Schlosser on the basis of the specimen from the Oligocene of Quercy phosphorites already published by S. Schaub.
Comparison of the skull of “ C. ” incertum with that of the asiatic genus Cricetops Matthew and Granger and that of the North-American Eumys Leidy. These three genera of similar age display very distinct characteristics; their common origin must go back to the Eocene, as Wood believed.
Comparisons of the auditory regions of Ruscínomys and of Megacricetodon where important differences are noted. Comparison of the Cricetodontines from European Miocene with contemporary Cricetines. Contrary of the opinion held by Schaub, their anatomical differences do not seem suflicient to warrant the contention that none of the Cricetines derive from a form close to one of the known Cricetodontines. 

The study of the bovids from Al Jadidah (Hofuf Formation, Saudi Arabia) confirms that the fauna comes from a pre-Hipparion level. The Al Jadidah age is close to that of Fort Ternan (14 m.y.) and Beni Mellal, but cannot be older than that of Fort Ternan. The age of the Hofuf Formation is close to but slightly older than the oldest deposits of the Ngorora Formation (Kenya). 7 to 9 species have been recorded, of which 2 to 4 remain indeterminate. If the great specific diversity of te bovids from this locality gives evidence of immigrations from anterior Asia (Turkey) (e.g. Pachytragus Iigabuei sp. nov.), the bovid assemblage of Al Jadidah results in fact from a double influence: from the anterior Asia and mainly from Africa (e.g. the Caprotragoides lineage and the Neotragini? Homoiodorcas). The Al Jadidah bovids reflect, on the whole, the predominant character of open to very open environment, which supports the conclusions drawn from our two preliminary studies. 

L'ouvrage est divisé en trois grandes parties traitant successivement: I. l'anatomie ("Proboscidean flesh and bones"), en abordant la taxonomie, l'allure générale et l'éco-éthologie des proboscidiens actuels et fossiles; II. les causes de mortalité collective naturelle et provoquée chez les actuels; III. les documents fossiles et l'extinction des formes anciennes d'Amérique du Nord. 

Abstract not available 

Two species lineages of North American late Paleocene Plesiadapis exhibit a pattern of size divergence from a common ancestral lineage. Time series of fossils in each of these lineages are analyzed to test the idea that size divergence represents competitive character displacement. The critical factor in a test of character divergence is showing that divergent lineages evolved directionally rather than randomly (multifactorially). Analysis of evolutionary rates and their temporal scaling in Plesiadapis shows that both divergent species lineages have the scaling slope expected for lineages evolving randomly rather than directionally, and size divergence in Plesíadapis does not represent character displacement. Rates of evolution commonly observed on a per-generation time scale are high enough to produce character displacement within a few generations. Thus character displacement is not likely to be visible on scales of time that can be studied in the fossil record. 

Micro-CT imaging is an increasingly popular method in paleontology giving access to internal structures with a high resolution and without destroying precious specimens. However, its potential for the study of hypoplasia defects has only recently been investigated. Here, we propose a preliminary study to test whether hypoplastic defects can be detected with micro-CT (μCT) scan and we assess the costs and benefits of using this method instead of naked eye. To do so, we studied 13 fossil rhinocerotid teeth bearing hypoplasia from Béon 1 (late early Miocene, Southwestern France) as positive control and 11 teeth of the amynodontid Cadurcotherium (Oligocene, Phosphorites du Quercy, Southwestern France), for which enamel was partly or totally obscured by cement. We showed that all macroscopically-spotted defects were retrieved on 3D reconstructions and selected virtual slices. We also detected additional defects using μCT scan compared to naked eye identification. The number of defects detected using μCT was greater in the Cadurcotherium dataset (paired-sample Wilcoxon test, p-value = 0.02724) but not for our control sample (paired-sample Wilcoxon test, p-value = 0.1171). Moreover, it allowed for measuring width and depth of the defects on virtual slices (sometimes linked to stress duration and severity, respectively), which we could not do macroscopically. As μCT imaging is both expensive and time consuming while not drastically improving the results, we recommend a moderate and thoughtful use of this method for hypoplasia investigations, restricted for instance to teeth for which enamel surface is obscured (presence of cement, uncomplete preparation, or unerupted germs). 

The eggshell of Nicobar scrubfowl (Megapodius nicobariensis) is described for the first time. Its egg porosity is calculated and discussed with data from several taxa (another megapode, some extant and fossil reptiles including a titanosaur group) in order to compare incubation types with eggshell structure. Eggshell microstructure reflects first phylogenetic traits and does not seem to have developed major adaptative features due to the incubation conditions, except for the pore canals. 

Perutherium altiplanerise THALER, 1967 from the Late Cretaceous of Peru has long been recognized as South America's oldest known placental mammal. Since its description Perutherium has been generally regarded as having condylarth affinity Based on our identification  of a unique notoungulate synapomorphy we recognize Perutherium as the oldest and the most generalized known member of that order. This new determination and the large taxonomic diversity (five families) of notoungulates in rocks of Paleocene age in Argentina and Brazil, favor a South American origin for this group. The occurrence of notoungulates in rocks of Late Paleocene age in Asia and North America is explained by dispersal of a notoungulate stock from South America to North America and from there to Asia.