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Because of their small size and vast abundance in various types of sedimentary rocks, microfossils have found a multitude of applications in geology, especially regarding biostratigraphy, correlations, and paleoenvironmental analysis. Organic-walled microfossils such as pollen, spores, and various organic debris derived from terrestrial plants are especially useful when studying terrestrial deposits. This chapter presents the many different groups of organic-walled microfossils, collectively called palynomorphs, and the different methods palynologists use to study and extract them from sediments and rocks. We present a biostratigraphic application, the use of the pollen and spore record across the Cretaceous-Paleogene boundary, which has proven to be one of the most precise and reliable means for pinpointing this major transition within terrestrial deposits.

Aquatifolia cf. fluitans Layers B to D (Fig. 6B, C) SPECIMENS. — MPZ 2010/1130 to MPZ 2010/1134 and MPZ 2009/342. DESCRIPTION Leaf orbicular to ovate, petiolate. Base cordate. Base angle wide obtuse. Petiole stout with an expanded fusiform float in its lower part. Float length is 60mm long and 17 mm wide in its central part. Leaf blade up to 39 mm long and 45 mm wide (no complete specimens). Margin crenate with tooth type convexconvex.Primary venation basal actinodromous with one medial vein branching up to the margin and four lateral primary veins which fork several times, gradually decreasing in thickness toward the margin. Angle between primary veins 45°. Branches from primary veins join to form polygonal large meshes. Secondary venation apparently craspedodromous.Tertiary and quaternary veins forming small polygonal meshes. REMARKS Ŋe unique combination of spherical to fusiform floats and foliar lamina with Nymphaeaceae-like venation together with other characteristics is charateristic for the genus Aquatifolia Wang & Dilcher from the Hoisington III locality, Kansas, USA (Wang& Dilcher 2006a). Ŋe Spanish fossils are closely similar to the type species Aquatifolia fluitans (Wang & Dilcher 2006a), but because leaf margin and endings of veins are not well preserved,we hesitate to include the spanish material in the same species. Currently the genus has only been recovered from the Estercuel outcrop and the Hoisington III locality., Published as part of Sender, Luis Miguel, Villanueva-Amadoz, Uxue, Diez, Jose Bienvenido, Sanchez-Pellicer, Raquel, Bercovici, Antoine, Pons, Denise & Ferrer, Javier, 2012, A new uppermost Albian flora from Teruel province, northeastern Spain, pp. 373-397 in Geodiversitas 34 (2) on pages 373-397, DOI: 10.5252/g2012n2a7, http://zenodo.org/record/5380589, {"references":["WANG H. & DILCHER D. L. 2006 a. - Aquatic Angiosperms from the Dakota Formation (Albian, Lower Cretaceous), Hoisington III locality, Kansas, USA. International Journal of Plant Sciences 167 (2): 373 - 383."]}

Form-genus Desmiophyllum Lesquereux, 1878 Layers A to E (Fig. 5 A) SPECIMENS. — MPZ 2010/1040 to MPZ 2010/1052. DESCRIPTION Fragments of elongate strap-like leaves up to 12 cm long and 2 cm wide.Margins straight and reinforced.Base and apex not preserved.Venation consists of numerous gross veins, c. 25 veins per cm, running parallel to leaf margins. Another four thin veins extended between two gross veins making a total of c. 125 veins per cm. REMARKS Similar leaves were also found in the Aptian-Albian of western Europe (Coiffard et al. 2007), Canada (Bell 1956) and in Albian-Cenomanian deposits of Alaska (Spicer & Herman 2001) and Russia (Spicer et al. 2002)., Published as part of Sender, Luis Miguel, Villanueva-Amadoz, Uxue, Diez, Jose Bienvenido, Sanchez-Pellicer, Raquel, Bercovici, Antoine, Pons, Denise & Ferrer, Javier, 2012, A new uppermost Albian flora from Teruel province, northeastern Spain, pp. 373-397 in Geodiversitas 34 (2) on pages 373-397, DOI: 10.5252/g2012n2a7, http://zenodo.org/record/5380589, {"references":["COIFFARD C., GOMEZ B. & THEVENARD F. 2007. - Early Cretaceous angiosperm invasion of western Europe and major environmental changes. Annals of Botany 100 (3): 545 - 553.","BELL W. A. 1956. - Lower Cretaceous floras of western Canada. Geological Survey of Canada, Memoir 285, 331 p.","SPICER R. A. & HERMAN A. B. 2001. - Ne Albian- Cenomanian flora of the Kukpowruk River, western North Slope, Alaska: stratigraphy, palaeofloristics, and plant communities. Cretaceous Research 22: 1 - 40.","SPICER R. A., AHLBERG A., HERMAN A. B., KELLEY S. P., RAIKEVICH M. I. & REES P. M. 2002. - Palaeoenvironment and ecology of the middle Cretaceous Grebenka flora of northeastern Asia. Palaeogeography, Palaeoclimatology, Palaeoecology 184: 65 - 105."]}

Los registros paleobotánicos en la cuenca de Cameros son escasos y se encuentran limitados a unas pocas localidades. Se presentan dos nuevos registros procedentes de depósitos del Barremiense en las cercanías de Salas de los Infantes y de Hortezuelos (Burgos). La nueva flora de Horcajuelos-1, cercano a Salas de los Infantes, se corresponde con los depósitos fluviales de la Formación Pinilla de los Moros. El nivel inferior está dominado por restos de Tempskya, mientras que en el nivel superior aparecen abundantes registros de Onychiopsis cf. psilotoides, Regnellites, Ruffordia y Cladophlebis. Los registros palinológicos de las facies lacustres, equivalentes lateralmente, de la Formación Hortezuelos están dominados por una abundante y diversa asociación de esporas de helechos (principalmente Schizaeaceae) junto con coníferas (Classopollis y Araucariacites) y raros pólenes monosulcados de angiospermas, Palaeobotanical records of the Cameros basin are scarce and limited to a few localities. Two new records , mainly corresponding to Barremian deposits near Salas de los Infantes and Hortezuelos (Burgos) are presented. The new flora from Horcajuelos-1 near Salas corresponds to fluvial deposits of the Pinilla de los Moros Fm. A lower bed is dominated by Tempskya, while an upper layer includes abundant Onychiopsis cf. psilotoides, Regnellites, Ruffordia and Cladophlebis. The palynological records of the laterally equivalent lacustrine facies from the Hortezuelos Fm. are dominated by abundant and diverse fern spore assemblages (mainly Schizaeaceae) along with conifers (Classopollis and Araucariacites) and rare monosulcate angiosperm pollen

International audience

12 p.; International audience; Optical microscopy continues to be the preferred method for imaging in paleopalynology. While usefulness of other tools, such as the scanning electron microscope, is not questioned, the ease of use and timely results of optical microscopy remains unsurpassed. However, obtaining good quality photomicrographs requires the use of the highest magnifying power objectives available, which are inevitably associated with very limited depth of field. To avoid the need for multiple photomicrographs in order to fully describe each palynomorph, a software solution for reconstructing depth of field is proposed. This solution allows for keeping the main advantages of high magnifying power objectives (better resolution and improved contrast) while suppressing their main weakness. In addition, photomicrographs published using depth of field reconstruction have a more natural appearance, similar to when directly viewed with the eye under the microscope. While this paper deals primarily with the usage of depth of field reconstruction for the enhancement of palynological photomicrograph, the technique can be applied similarly to many other paleontological and geological objects as well.

National audience; Parallèlement à la nomenclature chronostratigraphique reconnue par l'ICS (International Comission on Stratigraphy), de nombreuses autres nomenclatures régionales ont étés développées pour subdiviser le Permien, possédant chacune un sens particulier selon le pays ou l'époque à laquelle le terme est employé. Un travail de synthèse a été effectué dans le but de clarifier l'utilisation et la signification des termes de la subdivision en trois partie (Autunien, Saxonien et Thuringien) du Permien, telle qu'utilisée en France. Ces termes utilisées souvent de manière abusive pour définir une chronostratigraphie parallèle du Permien, doivent abandonner définitivement ce sens au profit de la nomenclature de l'ICS déjà existante. Cependant, cette subdivision locale peut rester valide si on lui réserve un sens lithostratigraphique ou biostratigraphique : - Le Saxonien, défini à l'origine pour identifier les séries gréseuses rouges de Saxe, regroupe aujourd'hui la description de tout faciès rouge réputé azoïque reposant sur le Permien. N'étant pas indispensable car d'autres nomenclatures de description de faciès existent, ce terme peut être oublié. Si son utilisation est voulue, elle ne pourra être faite que dans un sens lithostratigraphique, décrivant les faciès des dépôts fluviatiles et de playa de la fin du Permien. - Le Thuringien, souvent considéré comme équivalent du Zechstein dans le bassin germanique, doit être utilisé dans son sens biostratigraphique, identifiant une macroflore et une microflore qui lui sont caractéristiques et aisément différentiables de celles que l'on retrouve dans l'Autunien ou au début du Trias. Au delà de ce problème de terminologie, l'intérêt réel du problème est de pouvoir établir des corrélations entre les séries des bassins Permiens français, et si possible de les étendre pour le domaine Ouest-téthysien, aboutissant à une mise en relation des séries continentales avec l'échelle internationale marine.