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In this contribution we revise the ammonite subgenus Pervinquieria (Styphloceras) van Hoepen, 1951, and show it to be a synonym of Pervinquieria sensu stricto. All of the species assigned to the subgenus by van Hoepen are interpreted as a single variable species, of which Pervinquieria (Collignonia) vallifera van Hoepen, 1951, is a further synonym.

The type, figured and cited material of thirteen species assigned by van Hoepen (1942, 1946) to his genus Ophryoceras, a synonym of Pervinquieria (Pervinquieria) Böhm, 1910, are described and illustrated, and shown to be a single variable Late Albian ammonite species. Pervinquieria salebrosa van Hoepen, 1942 is a further synonym. Van Hoepen (1946) referred a series of fragments to Ophryoceras sp. under four separate entries. We have not seen this material which we refer to as ?Ophryoceras spp. (a)–(d); they may be further synonyms of salebrosa.

The cosmopolitan Late Albian ammonite subgenus Pervinquieria( Deiradoceras) van Hoepen, 1931, and its synonyms Cechenoceras van Hoepen, 1941 and Mimeloceras van Hoepen, 1944, originally based on material from northern KwaZulu-Natal, are reviewed. The type material of the type species, Subschloenbachia prerostrata Spath, 1921, is revised and reillustrated, as are its numerous synonyms.

The lower Upper Albian ammonite genus Dipoloceras Hyatt, 1900 (subfamily Mojsisovicsiinae Hyatt, 1903) is represented in KwaZulu-Natal by the type species, D. cristatum (Brongniart, 1822), marker species for the base of the Upper Albian Substage. Rhytidoceras van Hoepen, 1931 (of which Drepanoceras van Hoepen, 1931, non Stein 1878 and Ricnoceras van Hoepen, 1941, are synonyms), previously regarded as subgenera of Dipoloceras, are afforded generic status as are its supposed synonyms Diplasioceras van Hoepen, 1946a, and Euspectroceras van Hoepen, 1946a. The type species of these genera are revised, and assigned to the subfamily Pervinquierinae Spath, 1926.

Background Myrtales is a species rich branch of Rosidae, with many species having important economic, medicinal, and ornamental value. At present, although there are reports on the chloroplast structure of Myrtales, a comprehensive analysis of the chloroplast structure of Myrtales is lacking. Phylogenetic and divergence time estimates of Myrtales are mostly constructed by using chloroplast gene fragments, and the support for relationships is low. A more reliable method to reconstruct the species divergence time and phylogenetic relationships is by using whole chloroplast genomes. In this study, we comprehensively analyzed the structural characteristics of Myrtales chloroplasts, compared variation hotspots, and reconstructed the species differentiation time of Myrtales with four fossils and one secondary calibration point. Results A total of 92 chloroplast sequences of Myrtales, representing six families, 16 subfamilies and 78 genera, were obtained including nine newly sequenced chloroplasts by whole genome sequencing. Structural analyses showed that the chloroplasts range in size between 152,214–171,315 bp and exhibit a typical four part structure. The IR region is between 23,901–36,747 bp, with the large single copy region spanning 83,691–91,249 bp and the small single copy region spanning 11,150–19,703 bp. In total, 123–133 genes are present in the chloroplasts including 77–81 protein coding genes, four rRNA genes and 30–31 tRNA genes. The GC content was 36.9–38.9%, with the average GC content being 37%. The GC content in the LSC, SSC and IR regions was 34.7–37.3%, 30.6–36.8% and 39.7–43.5%, respectively. By analyzing nucleotide polymorphism of the chloroplast, we propose 21 hypervariable regions as potential DNA barcode regions for Myrtales. Phylogenetic analyses showed that Myrtales and its corresponding families are monophyletic, with Combretaceae and the clade of Onagraceae + Lythraceae (BS = 100%, PP = 1) being sister groups. The results of molecular dating showed that the crown of Myrtales was most likely to be 104.90 Ma (95% HPD = 87.88–114.18 Ma), and differentiated from the Geraniales around 111.59 Ma (95% HPD = 95.50–118.62 Ma). Conclusions The chloroplast genome structure of Myrtales is similar to other angiosperms and has a typical four part structure. Due to the expansion and contraction of the IR region, the chloroplast genome sizes in this group are slightly different. The variation of noncoding regions of the chloroplast genome is larger than those of coding regions. Phylogenetic analysis showed that Combretaceae and Onagraceae + Lythraceae were well supported as sister groups. Molecular dating indicates that the Myrtales crown most likely originated during the Albian age of the Lower Cretaceous. These chloroplast genomes contribute to the study of genetic diversity and species evolution of Myrtales, while providing useful information for taxonomic and phylogenetic studies of Myrtales.

The uppermost Albian and lowermost Cenomanian succession at Abouda Plage, north of Agadir, in the Agadir Basin, western Morocco, is described in detail, and ammonites, microcrinoids and planktonic foraminifera are recorded and illustrated. The lower part of the Aït Lamine Formation yields ammonites indicative of the Pervinquieria (Subschloenbachia) rostrata and P. (S.) perinflata ammonite zones, and the Thalmanninella appenninica planktonic foraminiferan Zone. The base of the Cenomanian is identified at 42.2 m above the base of the Aït Lamine Formation, based on the lowest occurrence of the planktonic foraminiferan Thalmanninella globotruncanoides Sigal, 1948. Lower Cenomanian ammonites of the Graysonites adkinsi Zone enter 3 m higher in the succession. Microcrinoid zones AlR11 and AlR12 are identified in the Upper Albian, and the base of the CeR1 Zone coincides with the lowest occurrence of Cenomanian ammonites. The ammonite and microcrinoid occurrences and detailed distributions are very similar to those found in north central Texas, which, in the Cenomanian, was 5,300 km to the west. The new records suggest that the G. adkinsi Zone is equivalent to the uppermost (Lower Cenomanian) part of the Pleurohoplites briacensis Zone of the Global Stratotype Section for the base of the Cenomanian stage. An hiatus, of global extent, immediately underlies the base of the G. adkinsi Zone and is represented in the Agadir Basin by an erosion surface containing bored and encrusted hiatus concretions.

The Pyrenees are the result of the structural inversion of a rift of general direction N110E, established at the articulation of the European and Iberian plates. This rift was created by left-lateral transtension with severe crustal thinning during the latest Early Cretaceous and Mid-Cretaceous. Its inversion, which led to the uplifting of the Pyrenean chain, took place gradually, by transpression from east to west, during the Late Cretaceous followed by an Eocene collision. From historical fieldwork, this note mainly focuses on the rifting period at the scale of the Pyrenean domain. It clearly shows the fundamental role of the stratigraphic approach in structural interpretation. Although synchronous at the scale of the Pyrenees, the Cretaceous extension is more important in the western part of the chain, near the Bay of Biscay. It is therefore at this location, within the Tardets-Mauléon Basin, that the various stages of creation and evolution of the rift could be clearly recognized with, successively: (1) an epirogenic pre-rifting stage, during which the facies lines, submeridian during the Jurassic, gradually change into N110E during the Neocomian before giving way, in the Early Cretaceous (Barremian-Gargasian), to a moderate acceleration of subsidence and, consequently, to the gentle uplift of a southern and western margin, future High Primary Belt (also often called Axial Zone) and Landes Plateau, initiating the next stage; (2) a major, brittle, newly identified rifting stage in the Latest Aptian (Clansayesian) and Early Albian. It is characterized by the installation of elongated lows on the downthrown side of transverse N20 normal faults, active diapirism of the Triassic evaporites and central detachment of the post-Triassic cover. During the Mid-Albian, a major surface of stratigraphic unconformity, often associated to uplift, erosion, and local centripetal gliding of the basin borders, marks a new structural organization, a rapid mantle ascent and the end of this episode. Although obscured by the later Pyrenean compression, the reconstructed basin geometry is interpreted as a “pull-apart” basin associated to a modest left-lateral motion; (3) a late rifting stage characterized by the collapse of the internal zones by rapid mantle cooling. The erosion of the coeval uplift of the southern High Primary Belt and the Landes Plateau feeds the accumulation of the thick, deep and transgressive unconformable formation of the Black Flysch of Mid-Albian to Early Cenomanian age in a larger coalescing basin. Faulting associated with a simple NS distension is only active on the last major border faults; (4) finally, a post-rift stage of Late Cretaceous age illustrated by the establishment of a passively subsiding basin, devoid of major deformations and whose heterogeneity of the previous depocenters is gradually erased. The Pyrenean transpression, later and less marked than in the eastern and central Pyrenees, allowed the conservation of most of these Cretaceous transtensive structures. Within the Tardets-Mauléon Basin, the Pernes and Col d’Urdach sector, the only Pyrenean location where the Mid-cretaceous transtension led to a proven underwater mantle exhumation, illustrates from outcrops the various stages that have marked the history of the Pyrenean Trough. Towards the east, along the Internal Metamorphic Zone, the Lourdes-Bagnères, Baronnies, Ballongue, Aulus and Saint-Paul de Fenouillet-Boucheville Basins, or those, further north like the Camarade and Quillan Basins, successively examined, testify to the same sedimentary and structural evolution. As in the case of the Tardets-Mauléon Basin, we deal here again with “pull-apart” type basins established on a thinned crust, arranged in transtensive or locally transpressive relays and separated by zones of thicker crust and shallower facies successions. The Mid-Albian unconformity is always present, heralding a general drowning of the North Pyrenean Trough and cessation of the extensional activity. The Pyrenean deformation, however, constitutes an obstacle for a precise geodynamic reconstruction, in particular in the eastern and central Pyrénées. Towards the west and north-west, in the South Aquitaine, Parentis and Basque-Cantabrian Basins, where Pyrenean deformation has far less obscured the rifting events, a very comparable Cretaceous geodynamic evolution is observed thus strengthening the present interpretation. Les Pyrénées résultent de l’inversion structurale d’un rift d’orientation générale N110E, établi à l’articulation des plaques européenne et ibérique. Ce rift a été créé par transtension sénestre avec amincissement crustal sévère au cours du Crétacé inférieur terminal et du Crétacé moyen. Son inversion qui a conduit à la surrection de la chaîne pyrénéenne s’est opérée graduellement, par transpression d’est en ouest, au cours du Crétacé terminal puis collision éocène. Cette note s’attache surtout à préciser les étapes critiques du rifting à partir des travaux historiques de terrain qui présentent une grande homogénéité à l’échelle pyrénéenne. Elle montre clairement le rôle fondamental de l’approche stratigraphique dans l’interprétation structurale. Bien que synchrone à l’échelle des Pyrénées, l’extension crétacée est plus importante dans la partie occidentale de la chaîne, à l’approche du Golfe de Gascogne. C’est donc à cet endroit, au sein du bassin de Tardets-Mauléon, qu’ont pu être clairement reconnus les divers stades de création et d’évolution du rift avec, successivement: (1) un stade de pré-rifting de type épirogénique, au cours duquel les lignes d’isofaciès, subméridiennes au Jurassique s’orientent progressivement à N110E pendant le Néocomien avant de laisser place au Crétacé inférieur (Barrémien-Gargasien) à une accélération modérée de la subsidence, et par réaction au soulèvement d’une marge sud et ouest (future Haute Chaîne souvent appelée également Zone Axiale) et Plateau Landais, prélude au stade suivant ; (2) un stade de rifting majeur, cassant, nouvellement identifié dans l’Aptien terminal (Clansayésien) et l’Albien inférieur. Il est caractérisé par la mise en place de gouttières associées à des failles transverses N20 à jeu normal avec diapirisme des évaporites triasiques, décollement et glissement centripète local de la couverture post-triasique bordière et remontée mantellique rapide. À l’Albien moyen, une surface de discontinuité stratigraphique majeure, souvent associée à une remontée des bordures du bassin et à leur érosion, ainsi qu’à l’ascension rapide du manteau, marque la fin de cet épisode. Quoique rendue difficile par la tectonique compressive pyrénéenne, la reconstruction proposée de la géométrie du Bassin de Mauléon s’accorde avec un bassin de type pull-apart associé à un régime décrochant senestre de modeste ampleur ; (3) un stade de rifting tardif caractérisé par l’effondrement des zones internes et le rapide refroidissement mantellique. Le soulèvement et l’érosion de la Haute Chaîne méridionale et du Plateau Landais conduisent à l’accumulation de l’épaisse formation discordante profonde et transgressive du Flysch Noir d’âge albien moyen à cénomanien inférieur, dans un bassin unique associé à une distension N–S sur les dernières failles bordières ; (4) enfin, un stade post-rift d’âge crétacé supérieur illustré par la mise en place d’un bassin subsident passif, dépourvu de déformations majeures et dont l’hétérogénéité des dépocentres précédents est progressivement effacée. La transpression pyrénéenne, plus tardive et moins accusée que dans les Pyrénées orientales et centrales, a permis la conservation de la plupart de ces structures transtensives crétacées. Au sein de ce bassin de Tardets-Mauléon, le secteur des Pernes et du Col d’Urdach, seul emplacement pyrénéen où la transtension mésocrétacée a conduit à une exhumation mantellique sous-marine accomplie, illustre à l’affleurement les diverses étapes qui ont jalonné l’histoire du sillon dans son ensemble. Vers l’est, le long de la Zone Interne métamorphique, les bassins de Lourdes-Bagnères, des Baronnies, de Camarade, de la Ballongue, d’Aulus et de Saint-Paul de Fenouillet-Boucheville, ou ceux, nord ou sous-pyrénéens, de Camarade et Quillan, successivement examinés, témoignent dans l’ensemble de la même évolution sédimentaire et structurale. Comme dans le cas du bassin de Tardets-Mauléon, il s’agit ici encore de bassins de type pull-apart établis sur une croûte amincie, disposés en relais de décrochement transtensifs ou localement transpressifs et séparés par des zones de haut-fond à croûte plus épaisse. La discontinuité de l’Albien moyen y est partout présente. La déformation pyrénéenne constitue cependant un obstacle pour une reconstitution géodynamique précise, notamment dans les Pyrénées orientales et centrales. Vers l’ouest et le nord-ouest, dans les bassins sud-aquitains, de Parentis et basco-cantabrique où cette déformation a beaucoup moins profondément affecté les structures issues du rifting, s’observe une évolution géodynamique crétacée très comparable, renforçant ainsi l’interprétation proposée.

Over 130 species are documented from the Upper Albian, Cenomanian and Upper Turonian Fahdène Formation and correlatives in Central Tunisia and northern Algeria, based on material described by Henri Coquand (1852, 1854, 1862, 1880), Léon Pervinquière (1907, 1910), Georges Dubourdieu (1953), Jacques Sornay (1955), and new collections. The material consists predominantly of limonitic nuclei, together with adults of micromorphs. There is no continuous record, and a series of faunas are recognised that can be correlated with the zonation developed in Western Europe. These are the Upper Albian Ostlingoceras puzosianum fauna, Lower Cenomanian Neostlingoceras carcitanense and Mariella (Mariella) harchaensis faunas, the upper Lower to lower Middle Cenomanian Turrilites scheuchzerianus fauna, Middle Cenomanian Calycoceras (Newboldiceras) asiaticum fauna, Upper Cenomanian Eucalycoceras pentagonum fauna, and the Upper Turonian Subprionocyclus neptuni fauna. Two new micromorph genera are described, Coquandiceras of the Mantelliceratinae and Cryptoturrilites of the Turrilitinae. Most of the taxa present have a cosmopolitan distribution, with a minority of Boreal, North American and endemic taxa.

Deformation in intraplate domains is usually considered as a consequence of tectonic events at plate boundaries. Nevertheless, the occurrence of intraplate earthquakes such as the recent Le Teil event in the south of France along the Cévennes Fault System (CFS), on 11 November 2019, Mw = 4.9, questions whether this far-field deformation only occurs during tectonic pulses at plate boundaries, or if it corresponds to low-intensity but regional continuous deformation through time. To address this question, we have coupled U–Pb geochronology of fault-related calcites with structural analysis along a major fault system (the CFS) in the South-East Basin, France. We evidence (1) an Albian activity of the CFS and (2) a continuous compressional activity of the CFS and satellite structures during the whole Eocene and probably during the Late Cretaceous – Palaeocene, including periods (e.g. Lutetian) usually considered as phases of tectonic quiescence. We thus demonstrate that the tectonic reactivation of this intraplate fault system is not restricted to periods of high rates of deformation at plate boundaries.

In this paper, we present a sedimentary and structural analysis that together with maps, sections and new Ar/Ar data enable to describe the tectono-sedimentary evolution of the Mauléon hyper-extended rift basin exposed in the W-Pyrenees. Hyper-extension processes that ultimately resulted in exhuming mantle rocks are the result of the subsequent development of two diachronous detachment systems related to two evolutional stages of rifting. An initial Late Aptian Early Albian crustal thinning phase is first recorded by the development of a crustal necking zone controlled by the north-vergent Southern Mauléon Detachment system. During a subsequent exhumation phase, active faulting migrates to the north with the emplacement of the Northern Mauléon detachment system that exhumed north section thinned continental crust and mantle rocks. This diachronous crustal thinning and exhumation processes are also recorded by the diachronous deposition of syn-tectonic sedimentary tracts above the two supra-detachment sub-basins. Syn-tectonic sedimentary tracts record the progressive exhumation of footwall rocks along detachment systems. Tectonic migration from the southern to the northern Mauléon Detachment system is recorded by the coeval deposition of “sag” deposits above the necking zone basin and of syn-tectonic tracts above exhumed rocks north section. Located on a hanging-wall situation related to the Mauléon hyper-extension structures, the Arzacq Basin also records a major crustal thinning phase as shown by its subsidence evolution so as by deep seismic images. The absence of major top-basement structures and its overall sag morphology suggest that crustal thinning processes occurred by decoupled extension of lower crustal levels contrasting with the Southern Mauléon Detachment system. Reconciling observations from the Mauléon and Arzacq Basins, we finally propose in this paper that they were the result of one and the same asymmetric crustal thinning and exhumation processes, where extension is accommodated into the upper crust in the Mauléon Basin (lower plate basin) and relayed in ductile lower crust below the Arzacq Basin (upper plate basin).