Pachyceras arenosum (Waagen) (Ammonitina,Pachyceratidae)du Callovien du Kutch: Nouvelles definition et position systematique

The revision of Waagen's figured specimens from Kutch (India) shows that “Stephanoceras arenosum” after being considered as a Macrocephalites and than as a Mayaites is really a Pachyceras. This species is morphologically very close to the microconch of Pachyceras la landeanum (d'ORBIGNY) from Lamberti zone (Upper Callovian) of Western Europ. Its validity and that of others species of this genus collected in India is discussed. Its importance for stratigraphical correlations between european and indo-malagasy provinces is pointed out.     

Un nouveau Tachyoryctes (Mammalia,Rodentia) du bassin pliocene de Hadar (Ethiopie)

A new species of Tachyoryctes (Mammalia, Rodentia): T. pliocaenicus from the Hadar Formation (Ethiopia) ispresented in this study. It is considered here as an ancestral from T. splendens. Since it also shares characteristics with fossil Rhizomyidae (Kanisamys) from Asia, this species may represent a direct descendant of the latter and would have immigrated to East Africa before the middle Pliocene. This interpretation would agree with the attribution of the genus Tachyoryctes to the family Rhizomyidae. Moreover, the Hadar Paleoenvironment is partially reconstitued from data pertaining to the ecology of T. splendens.     

Presence de Gazella deperdita (Gervais) 1847 du gisement du Miocene superieur (Turolien) des Mistrals (Vaucluse,Sud-Est de la France)

Among the two bovid genera represented in the turolian locality Mistrals I, Gazella and Miotragocerus, the most abundant is a gazelle which, after comparison with Gazella deperdita from the Mont-Luberon, turns out to belong to this species. Resemblances between the two faunas, already noticed in the study of the Hipparions, are thus comfirmed.     

Une espèce nouvelle du Kimméridgien du Portugal (Estremadura): Aulacomyella abadiensis nov. sp. (Bivalvia,Posidoniidae)

The Kimmeridgian Series situated at the North ofLisbon is included in the Portuguese Lusitanian basin. Its sandy clays pelagic facies with planctonic foraminifera contains a new species of bivalvia: Aulacomyella abadiensis related to A. neogeaeImlay from the Middle Kimmeridgian of Mexico and from the Kimmeridgian of Crimea. This species confirms the Middle Kimmeridgian.     

Decouverte du genre Iowaphyllum (Tetracoralliaire) dans un biostrome eodevonien du Cotentin

After a few remarks on the coral fauna in deposits near La Roquelle in Cotentin, the genus Iowaphyllum is identifiedfor the first time in France. One species (I. bohemicum) is described here; it brings new paleogeographic and stratigraphic data.     

Ammonites du Toarcien du Haut Atlas central (Maroc)

In the central High Atlas, the Toarcian Stage is represented by a marl and marly limestone series of variable thickness. Two sections have been studied: Amellago (500 m) and Aït Athmane (100 m). Ammonites from the two sections allowed to characterize the Polymorphum, Levisoni, Bifrons, Gradata, and Speciosum zones. The Polymorphum Zone provided, among others: Dactylioceras (Eodactylites) mirabile, D. (E.) pseudocommune, Dactylioceras (Orthodactylites) aff. crosbeyi and Neolioceratoides aff. hoffmanni; the Levisoni Zone provided a rich ammonite fauna composed of, Calliphylloceras nilssoni, Dactylioceras (Orthodactylites) cf. semiannulatum, Eleganticeras exaratum, Harpoceras falciferum, H. pseudoserpentinum, H. serpentinum, H. subplanatum, Hildaites cf. forte, H. levisoni, H. cf. serpentiniformis, H. cf. subserpentinus, H. striatus, H. wrighti, Lytoceras siemensi, Lytoceras sp., Maconiceras soloniacense, Phylloceras sp., Polyplectus pluricostatum et Polyplectus sp.; the Bifrons Zone provided Eleganticeras sp., Harpoceras subplanatum?, Hildoceras bifrons, H. lusitanicum, H. semipolitum, H. sublevisoni, Hildoceras sp., Porpoceras gr. vortex – verticosum; the Gradata Zone was characterized by Pseudocrassiceras bayani, P. frantzi, Pseudocrassiceras sp., Pseudocrassiceras sp. indet.; and the Speciosum Zone provided an Hammatoceras aff. insigne. These species have been described and illustrated for the first time for the central High Atlas. Most of them are common to several basins of the north Tethyan margin and the Subboreal Domain of NW Europe.     

Les Pseudholaster (Echinoidea,Holasteroida) du Crétacé de France

In the order of Holasteroida, the fossil record highlights a contradiction between the genus Pseudholaster that appears in the Aptian, whose plastron is prostostern close to the Jurassic ancestors and the genus Holaster, which appears in the Valanginian, whose meridostern plastron appears more derived. This inconsistency can be explained by the ignorance of the plastronal architecture on the part of the early authors. A review of the species of Pseudholaster from the Cretaceous period of France was therefore carried out. The objective was to statistically determine the discriminating morphological characters, and to study the modifications of the architecture of the interambulacrum 5 of the French species belonging to this genus, as well as to the species included in the genus Holaster incorrectly by earlier authors. This review of the species of the genus Pseudholaster begins with a study of the ontogeny of the species Holaster intermedius Münster in Goldfuss, 1826–1833, first representative of the genus Pseudholaster, which appears in the Hauterivian in the Parisian and Rhodano-vocontian basins. The modifications during growth concern the overall shape, but also the plastron architecture: the number of plastron plates increases while the number of plates located between the peristome and the periproct remains fixed. The plastron of this species is protosternal and not meridosternal as Lambert pointed out. The labrum is cupuliform in contact with the second sternal 5a2 by a narrow digitation. However, this arrangement differs from that observed on a protosternal breastplate. This apomorphism of the plastron plate pattern, called “labrotaxienne”, is found in all the Pseudholaster studied, and the study of the architecture of the interambulacrum 5 also reveals a gradual decrease in the number of preanal plates between the oldest (Hauterivian) and the younger (Cenomanian-Lower Turonian) species studied. Most of the French species have been revised, with some synonyms. A new species, P. neraudeaui, is the last known Pseudholaster dated from the upper Cenomanian and lower Turonian of southwestern France. Our study illustrates the evolution of the genus Pseudholaster between the Hauterivian and the early Turonian in France. The interest of the study is to show that the appearance of the genus Pseudholaster is older than that of the genus Holaster. Pseuholaster intermedius, of Hauterivian age, possesses a derived protostern plastron called here “labrotaxien” and not meridostern as defined historically by Lambert, and to reveal that the number of preanals decreases over geological time. This data is essential for future phylogenetic studies. On a palaeobiogeographical level, the study reveals the expansion of the genus Pseudholaster during early Cretaceous in western Europe, with diversification during the Albian, its disappearance during late Cenomanian in the Paris basin while it still persists in the Aquitain basin, its predilection for circalitoral environments.     

Le genre leptaenopyxis (brachiopoda,leptaenidae) dans le Devonien du Massif Armoricain (France)

The study of genus LeptaenopyxisHavlicek, 1963 in the Lower Devonian from Armorican Massif allows to recognize four species: Leptaenopyxis kerfornei n. sp., Leptaenopyxis cf. bouei (Barrande), Leptaenopyxis sp. 1 and Leptaenopyxis sp. 2. These species were described, until now, under specific name boueiBarrande, 1848. From this study it follows some biostratigraphical and palaeobiogeographical results for the Armorican Massif and its relations with surrounding areas during Lower Devonian time.     

Les ammonites du Pliensbachien du jebel Bou Rharraf (Haut Atlas oriental, Maroc)

The originality of the sedimentary deposits and ammonite faunas in the jebel Bou Rharraf concerns “Ammonitico Rosso” facies, the westernmost known for the Pliensbachian, and a strong diversity of the Phylloceratida (Phylloceras, Calaiceras, Zetoceras, Partschiceras and Juraphyllites). The morphological disparity is also important in Galaticeras, Miltoceras and Tauromeniceras. If some taxa like Miltoceras taguendoufi and Mauretaniaceras elmii nov. gen., nov. sp. seem endemic to the High Atlas, most part of the Pliensbachien ammonites of the eastern High Atlas are classic for the southern margin of the western Tethys. Three genera (Callomoniceras, Appenninoceras, Mauretaniaceras) and three new species (Miltoceras involutum, Tropidoceras heterogeneum, Mauretaniaceras elmii) are described. An analysis using the “Discrete Cosine Transform” (DCT) method allows the better understanding of the morphospace of the rib patterns for the Fuciniceras from jebel Bou Rharraf. The biostratigraphy of the High Atlas is also improved with a set of 19 biohorizons for the Pliensbachian and the base of the Toarcian that are correlable with the Tethyan areas.     

Protoglobigérines et Oberhauserellidae (Foraminifères) du Bajocien-Bathonien du Jura méridional, France

A detailed investigation of the Bajocian-Bathonian protoglobigerinids and other globigerina-like foraminifera of the Southern Jura Mountains reveals an unsuspected diversity, with seven species of Conoglobigerinidae and two species of Oberhauserellidae. The discovery of two umbilical apertures in Oberhauserella as well as in some Conoglobigerina questions the generic taxonomy and raises the problem of comparisons with literature. For these reasons, five new species have been proposed: Oberhauserellaparocula and O. aff. parocula (with two apertures), “Conoglobigerina”trilocula and “C”.biapertura (with two apertures), C.solaperta and C.pupa. We demonstrate that Globuligerinabalakhmatovae (Morozova, 1961) (here emended) has a small globuligerine aperture as well as G. aff. dagestanica (Morozova, 1961). Despite the different taxonomic concepts, the Southern Jura Mountains associations, that are typical of the epicontinental platform, most closely match those of the Dagestan in the Caucasus. They clearly differ from those of the oceanic Tethys.     

Les Echinodermes Cincta du Cambriende la Montagne Noire (France)

Here is a revision of the Cincta Echinodermata, first in connection with stratigraphy bythe study of a series of organisms collected level by level in the Montagne Noire; secondly through the search of anatomical features characterizing genera and species. The first genera to appear is Decacystis, also known from Spain; Gyrocystis, not completely described, cannot be maintained; Trochocystis, from Bohemia, is missing. On the other hand, Sucocystis, Elliptocinctus (new genera for Tr. barrandei), Cephalocinctus, Cyclocinctus and Trochocinctus remain available and special to the Montagne Noire, except Cyclocinctus which is found also in Morocco.     

Les assemblages de diatomées du bassin messinien de Boudinar (Maroc nord-oriental)

The Messinian is one of the strongest biogenic silica accumulation periods in the world and more particularly in the Mediterranean, where it is marked by an important diatomitic sedimentation. In the Boudinar basin (Morocco north-Eastern, Western Mediterranean), the section of Sidi Haj Youssef, localised near the volcano of Ras Tarf, has approximately 100 m thickness of clayey-marly series in which 12 diatomitic levels of variable thickness are intercalated. The microfloristic study of diatoms on 86 samples, carried out in detail for the first time, made it possible to recognize 50 genus of diatoms (24 of centric and 26 of pennate) represented by 185 species (75 species of centric and 110 species of pennate). Four hundred individuals were taken from each sample to determine the relative frequency of each taxon within the diatoms assemblages. Thus, several assemblages were defined by the predominance of the following species: Coscinodiscusmarginatus, Actinoptychussenarius, Thalassionemanitzschioides, Actinocycluscurvatulus, Thalassiothrixlongissima, Rhizosoleniastyliformis and Actinocyclusehrenbergii. These diatoms assemblages display a littoral marine environment in communication with the opened sea. The abundance of the cold water species towards the base and the top of the section suggests broad exchanges of the basin with the Atlantic Ocean in Messinian. The predominance of the species Thalassionemanitzschioides and/or Thalassiothrixlongissima indicates periods of strong productivity that can be associated to upwelling systems.     

Euxinocythere (Ostracoda, Cytheridae, Leptocytherinae) du Miocène supérieur du Bassin de Turiec (Slovaquie) : taxonomie et paléoécologie

Eight new species of the family Cytheridae have been identified in the Upper Miocene deposits of the Turiec Basin (Slovakia), a small isolated intermountain depression. Six species are new - Euxinocythere aphroditae, E. delicata, E. lactea, E. minuscula, E. quadricostata, E. satyrica - and two are kept in open nomenclature. Their attribution to the genus Euxinocythere is based on arrangement of the hinge elements and of anterior marginal zone. This genus is known from brackish ostracod assemblages of the Paratethys and the Eastern Mediterranean while the species from the Turiec Basin are associated to fresh-water assemblages. The Euxinocythere have been found in littoral as well in deep limnic environment.     

Un atoposauridé (Crocodylia,mesosuchia) du portlandien de la Meuse (est de la France)

A small crocodilian skull from the lower Portlandian (Cyrena rugosa beds) of Brauvilliers (Meuse) is referred to an atoposaurid of the genus Alligatorium, apparently closely related to the species A. paintenense from the Tithonian of Franconia. It is the first reportof one of these small continental crocodilians from north-eastern France.     

Phoceana pliocenicaespece fossile du genre Phoceana (Bryozoa cheilostomata)

The genus Phoceana JULLIEN and CALVET was recorded only from the recent North Atlantic and the MediterraneanSea. We discovered a fossil species in the Lower Pliocene from southern Spain.     

Ptychochaetetes (Varioparietes) Resurgens nov. sp. (Cnidaria,Chaetetida) du Burdigalien du Bassin rhodanien (Miocène,France)

Discovery in the Miocene of a new species of Chaetetida belonging to the genus PtychochaetetesKoechlin, 1947. The organisms were gathered in the Burdigalian of the rhodanian basin: in Vaucluse (Valréas) and Ain (Valromey). More of the normal characters of Chaetetida, on thin sections, a particular structure and free spheres which are still enigmatic were seen.     

Le genre Dionide Barrande, 1847 (Trilobite)dans l'Ordovicien du Massif Armoricain et du Portugal

A new species of DionideBarrande, Dionide mareki nov. sp., is described from siltstones of Llandeilo age in the Armorican Massif and north Portugal. The known geographical distribution of this species presents new evidence for the strong palaeobiogeographical relationship, during the Llandeilo, between the Valongo district (near Porto) and the Martigné-Ferchaud and Saint-Julien-de-Vouvantes synclinoriums south of Rennes.     

Les Cervidae (Mammalia, Artiodactyla) du Pléistocène supérieur-Holocène ancien de la région du Parc National Serra da Capivara (Piauí, Brésil)

The Upper Pleistocene/Lower Holocene fossil-bearing sites of the Serra da Capivara National Park Region have yielded three cervid species: Mazama gouazoubira, M. americana and Blastocerus dichotomus, all currently living in South America, the two first in the region. A grand total of more than one hundred remains demonstrates the presence of Mazama gouazoubira in seven sites, mainly the Toca das Moendas, the Toca do Serrote do Artur, the Toca da Cima dos Pilão. This small species shows, since the Upper Pleistocene, a conspicuous tendency to reduce the average dimensions of its teeth and long bones. From the taller M. americana, only a dozen of remains were found in four sites, mainly the Sitio do Meio. In all of these it is sympatric with M. gouazoubira. It differs from this last one by its cheek teeth and its limb bones size and proportions. The oldest site where the species is known is Tarija (Bolivia, Middle Pleistocene) and it does not show any significant changes in size and proportions between recent and fossil samples. Sixteen remains of the large B. dichotomus were found in five sites, mainly the Toca das Moendas and the Toca da Barra do Antonião. The species is a rare fossil, but is frequently figured in the rock art painting of the region, where it is presently unknown.     

Description d'une nouvelle espèce et analyse morpho-fonctionnelle du genre Doryaspis White (Heterostraci) du Dévonien du Spitsberg

Doryaspis groenhorgensis nov. sp. is a new pteraspidiform from the lower devonian of Spitsbergen. The genus Doryaspis is now considered as the most abundant pteraspidiform of the Wood Bay formation, with five described species. Moreover, the pteraspidiform diversity of this formation has been under rated all along the XXth century. A morpho-functional analysis of the Doryaspis generic characters (e.g. flat dorsal shield, ventral pseudorostrum, long cornual plates) allows to consider two possible mode of life. However, none of the pelagic or benthic mode of life is better supported than the other. The same analysis introduce some interpretative hypothesis on histology and moving of the Pteraspidiformes. The Pteraspidiformes diversity of Spitsbergen is important for further Devonian circum-arctic comparisons (e.g. siberian platform).     

Les cératodontidés (Dipnoi) du Rhétien de Saint-Nicolas-de-Port (Meurthe-et-Moselle)

The ceratodontids from the Rhaetic locality Saint-Nicolas-de-Port are represented by a minute tooth-plate of Ceratodus kaupiAgassiz and about 200 tooth-plates of C. phillipsiAgassiz of all sizes. The C. kaupi tooth-plate is identical to the typical large ones. The small tooth-plates of C. phillipsi are very similar to those of C. «priscusFraas which is surely a young C. serratusAgassiz. C. «elegans Vollrath is a junior synonym of C. phillipsi which was previously described as C. «parvus Agassiz the holotype of which is a small tooth-plate of C. kaupi. The small tooth-plates of C. serratus, C. rectangulusLinck and C. concinnusPlieninger are little different. Biometry, association with larger tooth-plates and, in part, morphology permit the referral of tooth-plates to different species which are easy to distinguish on adult tooth-plates. The ceratodontids do not refute the reconstruction of the environnment as a littoral swamp based on sedimentology and other vertebrate fossil remains.