Cenomanian (Upper Cretaceous) bivalves from the Hameimat Massifs,north of Tebessa,Algeria: Systematics,biostratigraphy, palaeoecological and taphonomical remarks

In the eastern Saharan Atlas, particularly in the northern area of Tebessa Province (NE Algeria), the widely outcropping Cenomanian strata display a highly diversified macrofauna, among which bivalves are prominently represented. Twenty-eight bivalve species are here reported for the first time from the Cenomanian of Hameimat Massifs. Based on the stratigraphic distribution of these bivalves, five bivalve zones were recognized, i.e., Costagyra olisiponensis - Gyrostrea delettrei, Rhynchostreon suborbiculatum - Exogyra conica, Ceratostreon flabellatum, Ilymatogyra africana, and Pycnodonte vesicularis vesiculosa - Rastellum carinatum zones. Correlation to the ammonite biozones of the same region as follows: the Costagyra olisiponensis - Gyrostrea delettrei and the Rhynchostreon suborbiculatum - Exogyra conica zones occur respectively in the Sharpeiceras schlueteri and Mantelliceras saxbii subzones of the lower Cenomanian Mantelliceras mantelli Zone. The Ceratostreon flabellatum Zone is correlated with the middle Cenomanian Acanthoceras rhotomagense Zone. The Ilymatogyra africana Zone is correlated with the upper Cenomanian Calycoceras naviculare and the Metoicoceras geslinianum zones. Finally, the Pycnodonte vesicularis vesiculosa - Rastellum carinatum Zone represents the uppermost Cenomanian. Detailed analysis of biometrical and morphological features of these bivalve specimens provides the most reliable tool within the scope of palaeo-environmental reconstitution and the many palaeo-ecological variables that had driven the development and distribution of these macro-invertebrates. Comparison of these new data to those of adjacent south Tethyian areas supports the homogeneity of the Cenomanian bivalve faunas. Such an affinity underlines more vividly the favorable marine communications and currents driving the geographic dispersal of these bivalves during the Cenomanian.     

Upper Cenomanian bivalves from the Guir Basin (southwestern Algeria): Order Veneroida

The Upper Cretaceous rocks are widely distributed and well exposed in south Algeria and consist in beds rich in macrofauna. For the first time, twenty veneroid species (Bivalvia) are systematically described from the upper Cenomanian deposits of the Guir Basin. While three species were reported since long before [Granocardium desvauxi (Coquand), G. productum (J. de C. Sowerby) and Glossus aquilinus (Coquand)]; Lucina fallax Forbes, Crassatella (Rochella) tenuicostata (Seguenza), Protocardia hillana (J. Sowerby), G. productum (J. de C. Sowerby) var. byzacenica (Pervinquière), Arctica cordata (Sharpe), A. humei (Cox), A. inornata (d’Orbigny), A. picteti (Coquand), Tenea delettrei (Coquand), Paraesa faba (J. de C. Sowerby), Meretrix desvauxi (Coquand) were previously unknown from the Cretaceous of Algerian Sahara. Because of reduced degree of preservation, Sphaera cf. corrugata J. Sowerby, Maghrebella cf. forgemoli (Coquand), Maghrebella sp., Granocardium cf. carolinum (d’Orbigny), Protocardia sp. and Meretrix sp. are tentatively determined. The studied material, found in the lower part of the “Calcaires de Sidi Mohamed Ben Bouziane” Formation, evidences palaeobiogeographic affinities occurring over a wide geographical area: from North Africa, southern Europe to Middle East and India. The present study provides new information to the knowledge of the upper Cenomanian palaeobiology of the studied region.     

Brittle stars from the upper Cenomanian of the Preafrican platform: First ophiuroid remains for the Cretaceous of Algeria

While Late Cretaceous ophiuroids are relatively well known in Europe, these faunas have been much less studied in North Africa. With the exception of some Tunisian assemblages preliminary described at the turn of the 21st century, nothing is known about the Cretaceous brittle stars of the southwestern Tethyan margin. The present paper seeks to bring the first data about hitherto unknown ophiuroids recently found in the early upper Cenomanian succession of the eastern side of the Preafrican trough (Menaguir section, Algeria). This “community” of brittle stars comprises at least eight species. Most of them are probably new, but have not been formally named here. These are representatives of the families Hemieuryalidae, Amphiuridae, Ophiodermatidae, Ophiacanthidae, Ophiopezidae and probably also Ophiomyxidae and Ophiobyrsidae. Almost all vertebrae are zygospondylous; no streptospondylous vertebrae indicate the absence of the order Euryalida here. Most of the ophiuroids belong to the orders Amphilepidida and Ophiacanthida. Ophiotitanos serrata, Ophiomyxa? aff. jekerica, Ophiojagtus? sp. and some other taxa resembling ophiuroid assemblages from the Late Cretaceous of central, western and northern Europe. With respect to the late Cenomanian age, the depth of the sea and the taxonomic composition, there are some similarities with ophiuroids of the Bohemian Cretaceous Basin. The mid-ramp subtidal facies suggests that brittle stars lived here in a warm, euphotic and probably shallow sea.     

Taxonomy of a platy coral association from the Late Cenomanian of the southern Corbières (Aude,France)

The Upper Cenomanian cover of the Palaeozoic Mouthoumet Massif (southern Corbières, Aude, France), on the southern flank of the Bézu anticline, shows accumulations of large platy corals. However, while being already presented in stratigraphic, palaeoecological and sedimentological contexts, these organisms have not been the subject of a palaeontological study. The coral fauna encompasses 16 species of the families Leptophylliidae, Microsolenidae, and Siderastraeidae and is here presented in detail.     

Cenomanian cheilostome bryozoans from Devon,England

The Cenomanian witnessed a spectacular evolutionary radiation of cheilostome bryozoans, both in terms of species diversity and morphological disparity. However, Cenomanian cheilostome faunas are inadequately known. Twelve species of cheilostome bryozoans are here described from the Cenomanian Beer Head Limestone Formation of SE Devon, England, a nearshore facies of limestones and sands. Two of the cheilostome species are new – Wilbertopora manubriformis sp. nov. and Foratella cervisia sp. nov. – and five cannot be identified beyond genus level. Syntypes of Foratella forata (d’Orbigny, 1853), the Senonian type species of Foratella Canu, 1900, are illustrated using SEM and a lectotype is chosen. All of the species present are neocheilostomes, which were larval brooders. Compared with the non-brooding malacostegans that dominate pre-Cenomanian faunas, most species have avicularia and extensive frontal walls, features probably adaptive against small predators.     

A new ripiphorid beetle from Upper Cretaceous Burmese amber sheds light on early evolution of the extant subfamily Ripidiinae (Coleoptera: Ripiphoridae)

Fossils belonging to Ripidiinae are rare. Here, we describe and figure a remarkable new genus and species of Ripidiinae, Protoripidius burmiticus gen. et sp. nov., from the Upper Cretaceous amber of Myanmar. Protoripidius can be placed in the extant subfamily Ripidiinae based on the widely separated and abbreviated elytra (in male), unfolded hind wings, simple claws and the absence of tibial spurs. Protoripidius bears many transitional features shedding new light on the relationships of the two extant tribes of Ripidiinae. The discovery also highlights the palaeodiversity of the subfamily Ripidiinae in the mid-Cretaceous.     

Roveacrinids (Crinoidea,Roveacrinida) from the Cenomanian-Turonian of southwest Algeria (Saharan Atlas and Guir Basin)

In the southwestern part of Algeria, the Cenomanian-Turonian marine deposits build up a prominent ledge in a perched syncline (Ksour Mountains, western Saharan Atlas) or at high radius of curvature (Guir Basin). The petrographical analysis of the Cenomanian-Turonian deposits of the Ksour Mountains and of the Guir Basin reveals unexpected assemblages of roveacrinoidal ossicles comparable with those formerly reported from the Tinrhert area. For the first time, isolated ossicles of genuine and undisputable Roveacrinidae are illustrated. Three sections, Djebel Rhoundjaia (western Saharan Atlas), Berridel and Kénadsa (Guir Basin), were scrutinized to recognize the microcrinoidal sections within the carbonate microfacies and to compile the successive occurrence of respective roveacrinid taxa (besides the classical search for standard index microfossils) in an attempt to pinpoint more precisely the position of the Cenomanian-Turonian boundary (C/T B). These assemblages are particularly morphologically and taxonomically diverse with three species of genus Roveacrinus and one of genus Orthogonocrinus. The presence of Saccocomidae (Applinocrinus) is especially unusual in such stratigraphic levels. The relative abundance and diversity of Roveacrinidae evidence a peak when approaching the C/T B. Such an event is recurring in the latest Cenomanian in various Tethyan and Atlantic areas. These fluctuations are consistent with a high surface-water productivity just before the C/T B.     

An apterous scelionid wasp in mid-Cretaceous Burmese amber (Hymenoptera: Scelionidae)

A remarkably specialized parasitoid wasp of the family Scelionidae (Platygastroidea) is described and figured from mid-Cretaceous (Cenomanian) amber of the Hukawng Valley in northern Myanmar. Geoscelio mckellari Engel and Huang, gen. et sp. nov., is unique for its combination of a compact body, 12 antennal flagellomeres, a 1-2-2 tibial spur formula, a distinct malar sulcus, deeply impressed notauli, complete reduction of the wings, and basal crenulae on the metasomal terga and sterna, among many other features, and is placed within a separate tribe, Geoscelionini Engel and Huang, trib. nov. This is the first flightless species of Platygastroidea known from the Mesozoic, and its affinities with other Mesozoic and extant lineages are discussed.     

Taxonomy, biostratigraphy and paleoecology of Cenomanian and Turonian ostracodes from the Western Interior Basin, Southwest Utah, USA

Cenomanian-Turonian ostracodes are reported from the western Colorado Plateau (Western Interior Basin) in the United States. Fifteen genera and twenty species are illustrated, six of which are new: Cytheromorphaperornata nov. sp., Looneyellaleckiei nov. sp., Asciocythereposterangulata nov. sp., Asciocytherearizonensis nov. sp., Cytheropteronclavifragilis nov. sp. and Hourcqiadakotaensis nov. sp. Three ostracode interval zones are proposed that broadly correspond to the existing late Cenomanian through to Middle Turonian Ammonite-zones of Kauffman et al. (1993). Paleoenvironments range from estuarine to coastal plain.     

Ostracodes from the Early Cenomanian of Jordan.A preliminary report

Ostracode faunas have been identified for the firsttime in Early marine Cenomanian sediments of the Ajlun Group (Jordan) outcropping East of the Jordan Rift Valley. The faunal assemblages contain 14 genera and 17 species. Sediments indicate the internal part of a carbonate platform. The Ostracodes are closely related to those of neighbouring regions; accordingly, in the Tethyan context, Jordan belongs to the North Africa — Middle East bioprovince.     

Truyolsodontos estauni n. gen., n. sp., Truyolsodontidae,a new family of lamniform sharks from the Cenomanian of northern Spain

Truyolsodontos estauni n. gen., n. sp. is described based on fossil teeth from the middle and upper Cenomanian of northern Spain. The species Protoscyliorhinus magnusLandemaine, 1991 is withdrawn from the genus Protoscyliorhinus and placed in this new one. For the new genus, the new family Truyolsodontidae is proposed.     

Upper Pliocene bivalve shell concentrations from the Lower Chelif basin (NW Algeria): Systematics,sedimentologic and taphonomic framework

Sedimentologic and palaeontological investigation of the Upper Pliocene Slama Formation in the Lower Chelif Basin (NW Algeria) led us to collect important bivalve assemblages for taxonomic and taphonomic purposes. A rather comprehensive inventory list of Upper Pliocene bivalves from northwestern Algeria is now available and consists of 30 species, 17 of which are extinct ones. Four principal taphonomic attributes were analysed: bioerosion, encrustation, fragmentation, and abrasion. Physical and biogenic sedimentary structures are used for palaeoenvironmental interpretations. The taphonomic, sedimentologic and ichnological characteristics of most of the deposits suggests they originated from discontinuous processes of winnowing and bypassing of sediments, probably due to the action of storms in shallow waters, mainly in the shoreface depositional environment. The bivalve assemblage is dominated by disarticulated valves and displays significant taphonomic alteration in the shells. Sclerobionts traces in shells particulary affect the oyster shells. Bioerosion traces are predominately those of clionid sponges (Entobia isp.), polychaetes (Maeandropolydora isp. and Caulostrepsis isp.), bivalves (Gastrochaenolites isp.), and of predatory gastropods (Oichnus isp.). Among the sclerobionts, the identified encrusters were juvenile oyster recruits, barnacles, polychaetes (serpulid tubeworms), bryozoans (Microporella sp. and Acanthodesia sp.), and vermetid gastropods (Petaloconchus intortus).     

Plant-dominated assemblage and invertebrates from the Lower Cenomanian of Jaunay-Clan,western France

Two fossil localities are reported on the “LGV SEA” railroad from the Lower Cenomanian of Jaunay-Clan (JC), near Poitiers, western France. The laminated mudstones yielded plant fossils including ferns (Cladophlebis, Osmundophyllum, Ruffordia goeppertii, Sphenopteris), conifers (Brachyphyllum, Dammarophyllum, Pagiophyllum), and terrestrial and aquatic freshwater angiosperms (Eucalyptolaurus depreii, Ploufolia). They are associated with a coleopteran insect that shows systematic affinities to the modern subfamily Chrysomelinae (Chrysomelidae). This assemblage suggests connections with arborescent vegetation growing in calm freshwater environment. Brackish to marine invertebrates also occur and include a dakoticancroid crab (Brachyura, Podotremata, Dakoticancroidea) and a few bivalves (Brachidontes). They suggest brackish episodes during pond sedimentation in a coastal environment. Lastly, vertebrates are represented by an isolated feather.     

Palaeobotanical investigation of a Cenomanian clay lens in Hucheloup Quarry,Maine-et-Loire,NW France: Taxonomic,stratigraphic and palaeoenvironmental implications

A Cenomanian clay lens in Hucheloup Quarry (Maine-et-Loire, north-western France) has yielded 82 foliar compressions and impressions, of which 62 were identified at several taxonomic levels. The plants are ascribed to diverse Pinales (27%), ferns (27%), Ginkgoales (26%), angiosperms (19%) and Cycadales (1%). The most abundant species in the assemblage are Frenelopsis alata (K. Feistmantel) E. Knobloch emend. J. Kvaček (Pinales) and Eretmophyllum obtusum (Velenovský) J. Kvaček (syn. E. andegavense Pons, Bourreau et Broutin) (Ginkgoales). Wood fragments, along with very well-preserved cuticles, have also been recovered and identified. The specimens are usually very fragmentary, indicating that they had been transported over a significant distance before deposition. The Hucheloup clay was probably deposited in a brackish lagoon or in the lower part of an estuary, possibly in an abandoned channel or on a sandbar. The allochthonous flora represents at least two plant communities that developed in a subtropical–tropical climate, and along a salinity gradient in the vicinity of a fluvial network. Use of the fossil-genus Eretmophyllum Thomas emend. Harris in Harris et al. is considered to be the correct choice for ginkgoalean leaves within European Cenomanian deposits; the genus Nehvizdya Hluštík is regarded as a junior synonym. The clay lens has also yielded a palynological assemblage. Although lacking unequivocal indicators of this age and including some taxa that are more typical of older rocks, the composition of the associated, very small megaspore assemblage recovered is consistent with a Cenomanian determination.     

The oldest nautiloid recorded from the Triassic Germanic Basin and the first ammonoid from the Aegean (Middle Triassic) of Poland

During the Triassic in Europe, the Germanic Basin extended from England in the west to the eastern border of Poland in the east. Although cephalopods are common in some Middle Triassic (Muschelkalk) horizons, there still persists a gap in the palaeontological record of the eastern part of the Germanic Basin, notably in the lowermost parts of the Lower Muschelkalk, spanning the latest Olenekian-Aegean interval. The present contribution attempts to fill this gap by presenting the first ammonoid (ceratitid Beneckeia sp.) and nautiloids (Germanonautilus cf. dolomiticus and G. cf. salinarius) from the Lower Gogolin Beds (Upper Silesia, Poland). These Germanonautilus are the oldest nautiloids found in the entire Germanic Basin.     

Dietary analysis across breeding seasons of Eleonora's Falcon Falco eleonorae on the western coast of Algeria

The study of the contents of 318 Eleonora's Falcon Falco eleonorae pellets, collected from three islands off the western coast of Algeria, allowed us to identify 134 prey items. These are divided into 55 families, 21 orders and five classes. These represent 92 insect species, 39 birds, one mammal, one gastropod and one fish. In terms of abundance, insects constituted the main part of the diet (80.7%), followed by birds (18.5%), mammals (0.7%), and fish and gastropods (0.1% each). Among the insects, the Hymenoptera were the most numerous (45.2%), with ants being the most frequent family. In the class of birds, passeriforms were most frequently found (12.3%). The dominant family in the bird class was the Apodidae with a frequency of 5%. In terms of biomass, birds dominated with 98.1% of the total biomass, followed by insects with 1.2%. The diet of these Eleonora Falcons of Algeria was thus diverse, but varied with breeding status. The study of the dietary variation of the Eleonora Falcon during the breeding period shows that insects were most frequently encountered during the three breeding stages, whereas birds were highly consumed during the fledging stage, with frequencies of 43.9%.     

Cupressus dupreziana A. Camus: distribution,decline and regeneration on the Tassili n'Ajjer,central Sahara

As soon as it was first discovered in 1924, on the heights of the Tassili n'Ajjer, Cupressus dupreziana (A. Camus) was declared an endangered species. The few ancient trees to be seen in the beds of wadis gave reason to suppose that they were isolated individuals left behind from a forest that had flourished in a damper climate. Attempts at a census of the trees were made on a number of occasions, the fullest, in 1972, reporting a total of 230 living specimens. The revision of this inventory between 1997 and 2001 has now enabled us to draw the boundaries of the present range of this species, to assess its rate of decline over the last three decades and, for the first time, to record some regeneration, with the presence of new, young trees.     

Implications paléobiogéographiques de la découverted'une nouvelle localité éocène à vertébrés continentaux en afrique nord-occidentale: El Kohol (Sud-Oranais,Algérie)

The new fossil locality of El Kohol is located on the southern flank of the Saharan Altas, near Brezina (Algeria). It has been discovered in a thick Palaeogene continental series divided into 4 members: a transitional gypsiferous member, a lower red detritic member, a middle marly-calcareous member, and an upper red detritic member. The new flora and fauna have been obtained by excavation and washing-screening of a marly level of the middle member. The main finds are charophytes, lower vertebrates, a marsupial and eutherian mammals (lipotyphlan Insectivora, hyracoids, creodonts and Proboscidea). Geological and palaeontological data allow to refer these fossil remains, at least provisorily, to the end of the early Eocene. Palaeobiogeographical comments are made about forms with Holarctic affinities.