Organic-walled dinoflagellate cysts from the Upper Cretaceous–lower Paleocene succession in the western External Rif, Morocco: New species and new biostratigraphic results

Geobios 47 (2014) 291–304

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Original article

Organic-walled dinoflagellate cysts from the Upper Cretaceous–lower Paleocene succession in the western External Rif, Morocco: New species and new biostratigraphic results§ Kore´ E´lyse´e Gue´de´ a,b,e, Hamid Slimani a,*, Stephen Louwye c, Lahcen Asebriy a, Abdelkabir Toufiq d, M’Fedal Ahmamou b, Iz-Eddine El Amrani El Hassani a, Zeli Bruno Digbehi e a

Laboratory of Geology and Remote Sensing, Scientific Institute, University Mohammed V-Agdal, avenue Ibn Batouta, P.B. 703, Rabat-Agdal, Morocco Laboratory of Geodynamic, Geoinformation and Geoenvironment, Faculty of Sciences, University Mohammed V-Agdal, avenue Ibn Batouta, P.B. 1014, Rabat-Agdal, Morocco c Research Unit Palaeontology, Ghent University, Krijgslaan 281/S8, 9000 Ghent, Belgium d Laboratory of Geosciences and Environmental Techniques, Faculty of Sciences, University Chouaı¨b Doukkali, B.P. 20, 24000 El Jadida, Morocco e UFR-STRM, University Felix Houphouet Boigny, 22 B.P. 582, Abidjan 22, Coˆte d’Ivoire b

A R T I C L E I N F O

A B S T R A C T

Article history: Received 10 January 2014 Accepted 23 June 2014 Available online 2 October 2014

Palynological investigation of the Upper Cretaceous–lower Paleocene succession from the Tahar section near Arba Ayacha in northwestern Morocco (westernmost External Rif Chain) reveals the presence of rich, diverse and well-preserved dinoflagellate cyst assemblages. For the first time in the study region, biostratigraphic interpretations based on the dinoflagellate cyst assemblages from the studied interval allow the recognition of the upper Maastrichtian and Danian. Relevant upper Maastrichtian–Danian global dinoflagellate cyst events include: the First Appearance Datum of the upper Maastrichtian species Disphaerogena carposphaeropsis, Glaphyrocysta perforata, and Manumiella seelandica; the Last Appearance Datum of the Cretaceous taxa Dinogymnium spp., Isabelidinium cooksoniae, and Pterodinium cretaceum; and the First Appearance Datum of the earliest Danian markers Carpatella cornuta, Damassadinium californicum, Membranilarnacia? tenella, and Senoniasphaera inornata. We formally describe the biostratigraphical range and potential of two new dinoflagellate cyst species, namely Nematosphaeropsis silsila Gue´de´ and Slimani nov. sp., and Pterodinium ayachensis Gue´de´ and Slimani nov. sp. Both species are found in the westernmost External Rif Chain and are restricted to the upper Maastrichtian. ß 2014 Published by Elsevier Masson SAS.

Keywords: Dinoflagellate cysts Taxonomy Biostratigraphy Upper Cretaceous Lower Paleocene Morocco

1. Introduction Until now, no precise age was provided for the deposits assigned to the ‘‘Senonian–Eocene’’ or ‘‘Upper Cretaceous–Eocene’’ in the western External Rif Chain of northern Morocco (Fig. 1). The sedimentary sequence consists mainly of marls and marly limestones intercalated with sandstone beds (Fig. 2). This marly facies has the potential to contain the Cretaceous–Paleogene (K–Pg) boundary. Previous dinoflagellate cyst studies have already documented the K–Pg transition in detail from the eastern

§

Corresponding editor: Se´verine Fauquette. * Corresponding author. E-mail addresses: [email protected], [email protected] (H. Slimani).

http://dx.doi.org/10.1016/j.geobios.2014.06.006 0016-6995/ß 2014 Published by Elsevier Masson SAS.

External Rif Chain at Ouled Haddou (Slimani et al., 2008, 2010, 2012; Slimani and Toufiq, 2013). A biostratigraphical analysis based on dinoflagellate cysts from the Tahar outcrop near the village of Arba Ayacha (Fig. 1(A)) has been attempted in order to refine the age model of the Upper Cretaceous to lower Paleocene sediments, to locate the K–Pg boundary, to report in detail the bioevents around this boundary, and to compare the results with well-known K–Pg boundary sections from middle latitudes of the Northern Hemisphere and elsewhere. The latter includes reference sections such as the Global Boundary Stratotype Section and Point (GSSP) at El Kef (Brinkhuis and Zachariasse, 1988; Brinkhuis et al., 1998), Aı¨n Settara (Dupuis et al., 2001), and Elle`s (M’Hamdi et al., 2013) in Tunisia, Stevns Klint (Hansen, 1977) in Denmark, Caravaca (De Coninck and Smit, 1982) in Spain, and sections in the USA (Firth, 1987; Moshkovitz and Habib, 1993; Habib et al., 1996; Olsson et al., 1997; Habib and

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Fig. 1. A. Location of the Tahar section (Arba Ayacha, western External Rif, northwestern Morocco). B. Simplified structural map of the Rif Chain. Modified after Suter, 1980a,b.

Saeedi, 2007; Prauss, 2009). Previous palynological studies have also reported on the K–Pg boundary succession elsewhere in Morocco such as the Phosphate Plateau (Pre´voˆt et al., 1979; Rauscher and Doubinger, 1982; Rauscher, 1985; Soncini and Rauscher, 1988; Soncini, 1990) and the Middle Atlas Mountains (Herbig and Fechner, 1994).

Here, we present a new dinoflagellate cyst biostratigraphy from the lower part of the sampled succession, and locate for the first time the K–Pg boundary in the western External Rif Chain. We also formally describe two new organic-walled dinoflagellate cyst species: Nematosphaeropsis silsila Gue´de´ and Slimani nov. sp. (Figs. 3(A–L), 4(A, B), 5) is newly found, and Pterodinium ayachensis

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Fig. 2. Stratigraphic range of selected dinoflagellate cysts (see Appendix A, List 1), including the range of the two new dinoflagellate cyst species described herein, lithology, sampling positions and CaCO3 content from the Upper Cretaceous-lower Paleocene succession at Tahar (Arba Ayacha, western External Rif, northwestern Morocco).

Gue´de´ and Slimani nov. sp. (Fig. 6(A–P)) has been previously recorded and illustrated under open nomenclature as Pterodinium? sp. C from the Danish North Sea (Schiøler and Wilson, 1993), the French Atlantic Pyrenees (Cavagnetto and Tambareau, 1998), and the Moroccan Rif (Slimani et al., 2010). 2. Geological setting The Rif Chain (Fig. 1(B)) in northernmost Morocco belongs to the Betic-Rif-Tell orogen and corresponds to the western termination of the Alpine belt. The chain forms the westernmost part of the Maghrebide belt, which extends along the North African coast, and continues eastward to Sicily and Calabria in southern Italy. The Rif Chain, the other Marghrebian belts and the Betic Chain developed as a result of the compressive tectonic regime between the African and European plates caused by the progressive opening of the Atlantic Ocean (Patriat et al., 1982; Guerrera et al., 1993; Chalouan et al., 2001; Michard et al., 2002). The Rif Chain forms the southern limb of the Gibraltar Arc, which is a tight orogenic arc in the western Mediterranean region. The Rif belt includes three major geological domains or nappe complexes, formed essentially of Mesozoic and Cenozoic terrains: the External Rif, the Maghrebian Flysch nappes, and the Internal Rif (Fig. 1(B)) (Suter, 1980a; Durand-Delga, 1980; Chalouan et al., 2001). The

External Rif consists of a fold-and-thrust belt detached along the Upper Triassic evaporitic beds from the attenuated crust of the North African margin (Suter, 1980b; Benyaich, 1991; Chalouan et al., 2001). In the Tanger Unit of the western External Rif, where the studied Tahar section is located, the marls and marly limestone succession has been labelled as ‘Senonian–Eocene’ or ‘Upper Cretaceous–Eocene’ deposits (Suter, 1965; Andrieux, 1971; Asebriy, 1994; Leblanc, 1979) and still need to be precisely dated. In the eastern External Rif, detailed studies based on planktonic foraminifera (Toufiq et al., 2002; Toufiq and Boutakiout, 2005; Toufiq, 2006) and on dinoflagellate cysts (Slimani et al., 2008, 2010, 2012; Slimani and Toufiq, 2013) from the Ouled Haddou section allowed recognition of the Maastrichtian and Danian and revealed a complete record of the K–Pg transition. 3. Material and methods 3.1. The Tahar section The Tahar section is located in the Larache Province, northwestern Morocco, 2 km southward Arba Ayacha village, 70 km northeast of Larache and 2 km far from the road Larache–Tetouan (Fig. 1(A)). In order to identify the K–Pg transition, eleven samples equidistantly spaced were collected firstly in the 550 m-thick

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Fig. 3. Nematosphaeropsis silsila Gue´de´ and Slimani nov. sp. from the Upper Cretaceous–lower Paleocene succession of the western External Rif, Morocco. A–C. Holotype, sample Th4, slide 1, EF U43/3, specimen in ventral view. A. Low focus on the dorsal surface showing the precingular archeopyle and the paired trabeculae. B, C. Slightly differing high foci on the paired trabeculae and on the parasulcus, the posterior intercalary (1p) and the postcingular (10 0 0 ) paraplates. D, E. Paratype, sample Th5, slide 1, EF F36, specimen in right dorso-lateral view. D. Low focus on the left dorso-lateral surface showing the precingular archeopyle. E. High focus on the right dorso-lateral surface showing the paired chain-like trabeculae. F. Sample Th6a, slide 1, EF O43/3, specimen in right dorso-lateral view, high focus on the right dorso-lateral surface showing the antapical (10 0 0 0 ) paraplate. G–I. Sample Th6a, slide 1, EF W46/2, specimen in apical view. G, H. Slightly differing high foci on the apical (10 –40 ), precingular (10 0 –50 0 ) and sulcal anterior (as) paraplates and on the precingular archeopyle. I. Low focus on the antapical (10 0 0 0 ) paraplate. J–L. Sample Th6a, slide 1, EF V48/1, specimen in dorso-apical view. J. High focus on the precingular archeopyle and the apical (20 , 30 ) paraplates. K, L. Slightly differing low foci showing a partiform hypocystal paraplate arrangement. Scale bar: 40 mm.

interval, previously dated as Upper Cretaceous–Eocene. Seventeen samples were collected during a second field campaign in the interval dated as Upper Maastrichtian–Danian based on the dinoflagellate cyst analysis of the first eleven samples. This study focuses on the 250 m interval of pelagic deposits spanning the Maastrichtian–Danian boundary in this section. The lower part of the Upper Maastrichtian–Danian succession analyzed here consists of grey to blackish marls (150 m-thick) with intercalations of yellowish-brownish thin sandstone beds

(5–10 cm-thick), followed by grey to greenish marls (50 m-thick) attributed here to the upper Maastrichtian based on dinoflagellate cyst stratigraphy (Fig. 2). The lower sequence is overlain by Danian deposits with a thin bed (1 m-thick) of clayey marls at the base, followed by grey to greenish marls (50 m-thick). The section is exposed along the road connecting Arba Ayacha to Souk Sebt Beni Garfett. Samples were collected from the eastern flank of Jbel Tahar in ravines leading to el Aı¨acha River. Upper Cretaceous to Eocene deposits crop out in subvertical beds with a

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Fig. 4. Nematosphaeropsis silsila Gue´de´ and Slimani nov. sp. A. Sample Th6a, slide 1, EF V48/1, specimen in dorso-apical view, with a low focus on the ventro-antapical surface showing the precingular, sulcal, postcingular and antapical paraplate arrangement. The precingular, antapical 10 0 0 0 , posterior intercalary 1p and posterior sulcal ps paraplates show a partiform hypocystal arrangement. The apical paralate 40 , which has a contact with the anterior sulcal paraplate, and the strongly laevo-rotatore paracingulum suggest a S-type arrangement characterizing the Spiniferites complex (Evitt, 1985). B. Sample Th6a, slide 1, EF W46/2, specimen in apical view, with a high focus on the apical (10 –40 ), precingular (10 0 –50 0 ) and anterior sulcal (as) paraplates. The paraplate labeling follows Kofoid (1909); Taylor symbols are given between brackets (Evitt, 1985). Scale bar: 20 mm.

north–south strike. They form part of the Tanger Unit in the western Rif. The CaCO3 content in the Maastrichtian–Danian interval is very low (< 10%; Fig. 2) and shows variations. This is corroborated by the absence or rare occurrence of calcareous planktonic foraminifera. The low calcium carbonate content and the absence or scarcity of calcareous foraminifera might be interpreted as a result of dissolution caused by the tectonic activity and metamorphism (Leikine et al., 1991). This interpretation is supported here by the relatively dark colour of the palynomorphs. Nevertheless, the decrease in calcium carbonate content at the K–Pg boundary seems to be significant in this section. The same event was interpreted as the result of a prominent decrease in the delivery of carbonate due to the extinction of calcareous nannofossils and planktonic foraminifera (Alegret and Thomas, 2007). 3.2. Methods All (28) samples were processed following standard palynological preparation techniques as described by Wilson (1971). The processing involved an initial treatment of 40 g of sediment with cold HCl (20%), followed by digestion in HF (40% at 70 8C), in order to dissolve carbonates and silicates, respectively. Samples were rinsed with distilled water until neutrality between the acid treatments. Silicofluorides were removed through repeated hot baths (60 8C) with 20% HCl. Neither oxidation nor alkali treatments were applied, since this can lead to selective loss of palynomorphs. The residues were sieved on a nylon screen with a mesh size of 15 mm, stained with methyl-green and mounted in glycerine jelly on microscope slides. Two palynological slides per sample were examined with a transmitted light microscope (Olympus BX53). Photomicrographs were taken with a digital Olympus C-400 Zoom camera. The biostratigraphic results presented in this paper concern only the Maastrichtian–Danian interval. All slides and figured specimens, including the holotypes of N. silsila Gue´de´ and Slimani nov. sp. and P. ayachensis Gue´de´ and Slimani nov. sp., are kept in the botanical collection of the National Herbarium of Rabat (RAB), Scientific Institute, Mohammed V-Agdal University, Rabat, Morocco. England Finder (EF) specimen coordinates are given in the text and figures captions. References to authors of dinoflagellate cyst taxa in the text and Appendix A are provided by Fensome and Williams (2004), Dinoflaj2 (Fensome et al., 2008), Willumsen (2004), and Slimani et al. (2008, 2012). The morphological terminology follows Stover and Evitt (1978) and

Williams et al. (2000). The suprageneric classification follows Fensome et al. (1993). A list of selected dinoflagellate cyst taxa identified in the studied samples is given in Appendix A (List 1); the two new species described below were compared to species listed in Appendix A (List 2). 4. Systematic paleontology Division DINOFLAGELLATA (Bu¨tschli, 1885) Fensome et al., 1993 Subdivision DINOKARYOTA Fensome et al., 1993 Class DINOPHYCEAE Pascher, 1914 Subclass PERIDINIPHYCIDAE Fensome et al., 1993 Order GONYAULACALES Taylor, 1980 Suborder GONYAULACINAE Fensome et al., 1993 Family GONYAULACACEAE Lindemann, 1928 Subfamily GONYAULACOIDEAE (autonym) Genus Nematosphaeropsis Deflandre and Cookson, 1955 Nematosphaeropsis silsila Gue´de´ and Slimani nov. sp. Figs. 3–5 Etymology: Named after silsila (Arabic): with reference to the chain-like pairs of penitabular trabeculae Holotype: Sample Th4, slide 1, EF coordinates Y34 (Fig. 3(A–C)). Specimen dimensions: total length 60 mm, total width 58 mm, central body length 45 mm, central body width 43 mm. Paratype: Sample Th5, slide 1, EF coordinates F36 (Fig. 3(D, E)). Specimen dimensions: total length 57 mm, total width 53 mm, central body length 47 mm, central body width 45 mm. Repository: Botanical collection of the National Herbarium (RAB), Scientific Institute, Mohammed V-Agdal University, Rabat, Morocco. Type locality and horizon: Tahar section (Jbel Tahar, Arba Ayacha, Larache Province, northwestern Morocco), Upper Maastrichtian; sample Th4, ca. 64 m below the K–Pg boundary. Occurrence: Upper Maastrichtian (samples Th1 to Th7b, Tahar section; this study). Measurements (min-[mean]-max; 20 specimens measured): total length 54-[58]-80 mm, total width 40-[55]-69 mm, central body length 42-[52]-68 mm, central body width 26-[36]-47 mm, processes length 5–10 mm. Diagnosis: A species of Nematosphaeropsis characterized by a smooth central body wall and numerous sutural (gonal and intergonal) processes which are short, slender, closely and

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Fig. 5. Stratigraphic ranges of Nematosphaeropsis species.

equidistantly spaced, aligned and joined distally by chain-like pairs of thin membranous penitabular trabeculae. The paratabulation is clearly expressed by a precingular archeopyle type P and rows of parasutural processes on the central body, and by the trabecular shell. Description: This proximate to proximochorate dinoflagellate cyst is of intermediate size and has a spheroidal, ovoidal to rhomboidal central body. The hypocyst is more broadly rounded than the epicyst. The central body wall consists of a smooth, hyaline and thin autophragm with a maximum thickness of 1 mm. The central body bears numerous slender, solid or hollow processes 5 to 10 mm in length. The processes are proximally and distally slightly expanded and aligned in parasutural rows; they reflect a paratabulation. The length of the processes is quasiconstant on a single specimen, but varies slightly within the species. The processes are circular in cross-section, closely and

equidistantly spaced, proximally free, but connected distally by paired chain-like thin membranous penitabular trabeculae. The distal ends of the intergonal processes are finely bifurcate, whereas those of the gonal processes are trifurcate. Each process furcation gives rise to two penitabular trabeculae. The reflected gonyaulacoid paratabulation is 40 , 500 , 6c, 5–6000 , 1p, 10000 , 4–5s. The strongly laevorotatory paracingulum (max. width: 12 mm) is bordered by two parallel parasutural rows of processes. Every row ends distally with a pair of penitabular trabeculae. The parasulcus may be divided into 4 to 5 paraplates, with the anterior sulcal and posterior sulcal paraplates often clearly delineated. The apical paraplate 40 , which has a contact with the anterior sulcal paraplate (Figs. 3(G, H) and 4(B)), and the strongly laevo-rotatore paracingulum suggest a S-type arrangement characterizing the Spiniferites complex (Evitt, 1985). The precingular paralate 600 is undifferenciated and included in the sulcus, and only 5 precingular

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Fig. 6. Pterodinium ayachensis Gue´de´ and Slimani nov. sp. from the Upper Cretaceous–lower Paleocene succession of the western External Rif, Morocco. A–D. Holotype. Sample Th6, slide 1, EF F41, specimen in left lateral view. A, B. Slightly differing high foci on the precingular archeopyle and septa. C. Optical section. D. Low focus on the paracingulum. E, F. Sample Th3, slide 1, EF Q3/1, specimen in left latero-ventral view, slightly differing high foci on the untabulated parasulcus, the paracingulum and the postcingular (10 0 0 ) paraplate. G, H. Sample Th4, slide 1, EF D36/4, specimen in ventral view, slightly differing high foci on the precingular archeopyle and the paracingulum. I, J. Sample Th5, slide 1, EF O38, specimen in dorsal view. I. high focus on the precingular archeopyle and the paracingulum. J. Optical section. K, L. Sample Th6, slide 1, EF G31/4, foci on the lateral surfaces. M, N. Sample from the Ouled Haddou section, Morocco (Slimani et al., 2010), OH0, slide 1, EF T54/1, specimen in ventral view. M. Low focus on dorsal surface. N. High focus on ventral surface. O, P. Sample from the Ouled Haddou section, Morocco (Slimani et al., 2010), OH19, slide 1, EF F52/1, specimen in left latero-ventral view. O. Low focus on the precingular archeopyle. P. High focus on the left latero-ventral surface. Scale bar: 20 mm.

paraplates (100 –500 ) are delimited by parasutural features. The posterior intercalary 1p, the posterior sulcal ps, and the antapical 10000 paraplates show a partiform hypocystal arrangement (Figs. 3(K, L) and 4(A)). The postcingular paraplate 1000 is reduced and included in the sulcus. The postcingular paraplate 6000 does not have a contact with the antapical paraplate 10000 , and only three (3000 , 4000 , and 5000 ) among the postcingular paraplates, and the 1p and ps paraplates have contact with the pentagonal paraplate 10000 . The precingular archeopyle (type P) is formed by the loss of the paraplate 300 . The operculum is free.

Remarks: Wrenn (1988) erected the genus Unipontidinium in order to separate species with a single parasutural trabeculum from species of Nematosphaeropsis Deflandre and Cookson, 1955, with two penitabular trabeculae connecting gonal or gonal and intergonal processes distally. The same author transferred Nematosphaeropsis aquaeductus and N. grande to Unipontidinium based on the presence of a single parasutural trabeculum. Consequently N. silsila Gue´de´ and Slimani nov. sp. is here assigned to Nematosphaeropsis, since it bears two penitabular trabeculae connecting the gonal and intergonal processes distally.

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The new species resembles Unipontidinium grande by its numerous parasutural (gonal and intergonal) processes, which are short, uniform, aligned and closely spaced, but differs distinctly by its thinner and smooth (rather than thick and densely granulate) central body wall. The processes of the new species are furthermore connected distally by chain-like pairs of thin membranous penitabular trabeculae and not by a single membranous parasutural trabeculum. Furthermore, U. grande bears parasutural crests joining proximally. Nematosphaeropsis lativittatus Wrenn, 1988 also possesses numerous processes, but these are more widely spaced, relatively longer when compared to the central body diameter, and connected distally by very broad, often fused, ribbon-like trabeculae rather than chain-like paired thin membranous trabeculae. N. silsila Gue´de´ and Slimani nov. sp. differs from all other species of Nematosphaeropsis by its smooth central body wall and its numerous parasutural processes, which are short, slender, closely spaced and joined distally by two thin membranous penitabular trabeculae. Genus Pterodinium Eisenack, 1958 Pterodinium ayachensis Gue´de´ and Slimani nov. sp. Fig. 6 1993. Pterodinium? sp. C - Schiøler and Wilson, figs. pp. 3–10, pl. 4, fig. 7. 1998. Pterodinium sp. C in Schiøler and Wilson, 1993 Cavagnetto and Tambareau, fig. 9A. 2010. Pterodinium? sp. C of Schiøler and Wilson, 1993 - Slimani, Table S1. Etymology: Named after the village Arba Ayacha nearby the outcrop. Holotype: Sample Th4, slide 1, EF coordinates B54/1 (Fig. 6(A– D)). Specimen dimensions: total length 43 mm, total width 42 mm, central body length 35 mm, central body width 33 mm. Repository: Botanical collection of the National Herbarium (RAB), Scientific Institute, Mohammed V-Agdal University, Rabat, Morocco. Type locality and horizon: Tahar section (Jbel Tahar, Arba Ayacha, Larache Province, northwestern Morocco), Upper Maastrichtian; sample Th4, about 64 m below the K–Pg boundary. Occurrence: Upper Maastrichtian (samples Th1 to Th7b, Tahar section; this study); Maastrichtian of the Danish North Sea (Schiøler and Wilson, 1993); Selandian of Oraas, French Atlantic Pyrenees (Cavagnetto and Tambareau, 1998); Upper Maastrichtian–lower Danian at Ouled Haddou, northeastern Morocco (Slimani et al., 2010). Measurements (min-[mean]-max; 10 specimens measured): total length 43-[48]-53 mm, total width 40-[42]-46 mm, central body length 25-[31]-35 mm, central body width 23-[29]-35 mm, septa height 6-15 mm. Diagnosis: Small, spherical to ovoidal, smooth and thin-walled Pterodinium characterised by high parasutural septa with slightly convex distal margin, but generally unindented in the gonal areas; a continuous and regular overall cyst outline reflecting the central body shape. The paratabulation is expressed by the precingular archeopyle type P, the paracingulum and the parasulcus. Other indications of the paratabulation are often undiscernable. Description: This small-sized murochorate dinoflagellate cyst has a spherical to ovoidal central body. An apical horn is lacking. The wall of the central body consists of a smooth, hyaline and thin autophragm with a maximum thickness of 1 mm. Smooth and high parasutural septa (about half the central body diameter) arise from the central body. The distal margins of the septa are simple, slightly convex and enlarged, but generally unindented in the gonal areas. The overall cyst outline is continuous and regular and often has the same silhouette as the central body. The reflected gonyaulacoid paratabulation is 40 , 600 , 6c, 5000 , 10000 , Xs. The paracingulum, the

parasulcus and the precingular archeopyle are often the sole expression of the paratabulation. The paracingulum is slightly laevorotatory. The parasulcus is sigmoidal and untabulated. The archeopyle is formed by the release of the precingular paraplate 300 . The operculum is free or in place. Remarks: The features of this new species are identical to the specimens figured as Pterodinium? sp. C by Schiøler and Wilson (1993: pl. 4, fig. 7), Pterodinium sp. C in Schiøler and Wilson (1993) by Cavagnetto and Tambareau (1998: fig. 9A), and Pterodinium sp? C of Schiøler and Wilson (1993) by Slimani et al. (2010: table S1). It differs from all other Pterodinium species by its smaller size, the absence of an apical horn, the high parasutural septa (half of the central body diameter) with slightly convex distal margins that are simple and generally unindented in the gonal areas, and a continuous and regular overall cyst outline reflecting the central body shape. Pterodinium agadirense resembles the new species in its septa arrangement, but differs in being larger and having an apical horn. 5. Dinoflagellate cyst biostratigraphy The palynomorph assemblages from the Tahar section contain rich, diverse and well-preserved dinoflagellate cysts, spores, pollen, foraminiferal linings, acritarchs, and chlorophyte algae such as Palambages spp. More than 90% of the palynomorphs are dinoflagellate cysts (Appendix A, List 1). The new age determination of the analyzed interval in the study section is based on selected (Fig. 2) and well-known dinoflagellate cyst bioevents:  the First Appearance Datum (FAD) of the upper Maastrichtian species Disphaerogena carposphaeropsis, Glaphyrocysta perforata, and Manumiella seelandica;  the Last Appearance Datum (LAD) of Cretaceous taxa Dinogymnium spp., Isabelidinium cooksoniae, and Pterodinium cretaceum;  the FAD of the earliest Danian markers Carpatella cornuta, Damassadinium californicum, Membranilarnacia? tenella, and Senoniasphaera inornata.

The FAD of D. carposphaeropsis (Fig. 7(H)), Glaphyrocysta perforata (Fig. 7(E)), M. seelandica (Fig. 7(B)), and the LAD of I. cooksoniae (Fig. 7(C)) are indicative for the uppermost Maastrichtian. The LAD of Dinogymnium spp. indicates the top of the Maastrichtian (De Coninck and Smit, 1982; Brinkhuis and Zachariasse, 1988; Soncini, 1990; Eshet et al., 1992; Williams et al., 2004; Fensome et al., 2009; Slimani et al., 2010, 2011; M’Hamdi et al., 2013). These global dinoflagellate cyst bioevents suggest a latest Maastrichtian age for the 170 m-thick interval from Th2 to Th7b (from the lowest to highest occurrences of Upper Maastrichtian markers). The LAD of P. cretaceum (Fig. 8(K)) was previously recorded in the uppermost Maastrichtian (Schiøler and Wilson, 1993 as Pterodinium sp. B; Slimani et al., 2010, 2011; Slimani and Toufiq, 2013; M’Hamdi et al., 2013) and is considered here as a new marker of the K–Pg boundary, at least for the higher and middle latitudes of the Northern Hemisphere. This proposition needs confirmation from other K–Pg boundary sections elsewhere. The Last Occurrence (LO) of this species is observed here at the top of the Maastrichtian. The Highest Occurrence (HO) of Palynodinium grallator (Fig. 7(J)) is considered as a marker of the end of the Maastrichtian or the Maastrichtian–Danian boundary in higher northern latitudes (Hansen, 1977, 1979; Schiøler and Wilson, 1993; Habib et al., 1996; Schiøler et al., 1997; Slimani et al., 2011). Indeed, the latest Maastrichtian P. grallator Zone of Hansen (1977) is commonly used in these regions. However, the Lowest Occurrence (LO) of the latter

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Fig. 7. Dinoflagellate cysts from the Upper Cretaceous–lower Paleocene succession of the western External Rif, Morocco. A. Deflandrea galeata (Lejeune-Carpentier, 1942) Lentin and Williams, 1973, sample Th3, slide 1, EF E57; specimen in dorsal view, high focus on dorsal surface. B. Manumiella seelandica (Lange, 1969) Bujak and Davies, 1983, sample Th7a, slide 3, EF F50/2, specimen in ventral view, low focus on the wall ornamentation and the intercalary archeopyle. C. Isabelidinium cooksoniae (Alberti, 1959) Lentin and Williams, 1977, sample Th6, slide 1, EF G60, specimen in dorsal view, high focus on the wall ornamentation and the intercalary archeopyle. D. Damassadinium californicum (Drugg, 1967) Fensome et al., 1993, sample Th7d, slide 3, EF P23/4, focus on the processes. E. Glaphyrocysta perforata Hultberg and Malmgren, 1985, sample Th5, slide 1, EF Y37, specimen in ventral view, high focus on ventral surface. F. Riculacysta shauka Slimani et al., 2012, sample Th4, slide 1, EF J39, specimen in ventral view, high focus on ventral surface and processes. G. Senoniasphaera inornata (Drugg, 1970) Stover and Evitt, 1978, sample Th7a, slide 3, EF T47, specimen in dorsal view, low focus on ventral surface. H. Disphaerogena carpophaeropsis Wetzel, 1933, sample Th3, slide 1, EF E39/1, specimen in dorsal view, High focus on the wall structure, high focus on the precingular archeopyle. I. Membranilarcia? tenella Morgenroth, 1968, sample Th7c, slide 1, EF X32/2, specimen in antapical view, low focus on the apical archeopyle and processes. J. Palynodinium grallator Gocht, 1970, sample Th4, slide 1, EF Z44/2, specimen in dorsal view, low focus on ventral surface. K, L. Carpatella cornuta Grigorovich, 1969, sample Th7d, slide 3, EF J45/1, specimen in left dorso-lateral view. K. High focus on the precingular archeopyle and apical horn. L. Low focus on the ventral surface and antapical horn. M. Eisenackia margarita (Harland, 1979) Quattrocchio and Sarjeant, 2003, sample Th7a, slide 3, EF Z26, specimen in dorsal view, high focus on dorsal surface. Scale bar: 40 mm.

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Fig. 8. Dinoflagellate cysts from the Upper Cretaceous–lower Paleocene succession of the western External Rif, Morocco. A. Lejeunecysta izerzenensis Slimani et al., 2008, sample Th7c, slide 1, EF X32, specimen in dorsal view, high focus on the denticulate paracingulum. B. Magallanesium pilatum (Stanley, 1965) Quattrocchio and Sarjeant, 2003, sample Th7c, slide 2, EF L25, specimen in ventral view, high focus on the wall surface and processes. C. Spiniferella cornuta subsp. kasira Slimani et al., 2012, sample Th7c, slide 1, EF Y50/3, specimen in dorsal view, high focus on the precingular archeopyle and processes. D. Cassidium fragile (Harris, 1965) Drugg, 1967, sample Th7d, slide 1, EF D41, focus on the wall structure. E. Dinogymnium acuminatum Evitt et al., 1967, sample Th6, slide 2, EF K43/4, focus on the wall structure. F. Apteodinium fallax (Morgenroth, 1968) Stover and Evitt, 19785, sample Th7d, slide 3, EF H55/3, focus on the precingular archeopyle and wall structure. G. Pyxidinopsis ardonensis Jan du Cheˆne, 1988, sample Th7c, slide 1, EF H34/4, specimen in ventral view, low focus on the precingular archeopyle and the reticule wall surface. H. Ynezidinium pentahedrias (Damassa, 1979) Lucas-Clark and Helenes, 2000, sample Th7c, slide 1, EF D42/1, specimen in ventral view, high focus on the ventral surface showing the apical (10 , 40 ) and precingular (10 0 , 50 0 , and 60 0 ) paraplate arrangement characterizing the genus Ynezidinium. I. Impagidinium maghribensis Slimani et al., 2008, sample Th7c, slide 1, EF K47/2, specimen in lateral view, focus on the wall surface. J. Pterodinium cingulatum subsp. danicum Jan du Cheˆne, 1988, sample Th7c, slide 1, EF N39/3, specimen in ventral view, high focus on the sigmoid parasulcus. K. Pterodinium cretaceum Slimani et al., 2008, sample Th6, slide 1, EF B30/1, specimen in ventral view, high focus on the ventral surface showing characteristic discontinuous septa. L. Kallosphaeridium yorubaense Jan du Cheˆne and Adediran, 1985, sample Th7d, slide 3, EF T49/3, specimen in apical view, focus on the archeopyle. M. Kallosphaeridium parvum Jan du Cheˆne, 1988, sample Th7d, slide 3, EF Y32, specimen in dorsal view, high focus on the dorsal surface and wall structure. N. Xenicodinium delicatum Hultberg, 1985, sample Th7d, slide 2, EF T34, specimen in dorsal view, high focus on the precingular archeopyle and wall structure. Scale bars: 40 mm (scale bar in E applies to specimens A–E; scale bar in K applies to specimens F-N).

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species was recorded in sediments exactly at the K–Pg boundary in the Tethyan realm at El Kef (Brinkhuis et al., 1998) or above the K– Pg boundary at Ouled Haddou (Slimani et al., 2010), and its HO was observed at about 19 to 25 cm above the boundary in these areas. The occurrence at or just above the K–Pg boundary of this typical higher northern latitude species is interpreted by Brinkhuis et al. (1998) as the result of a southward migration as a consequence of temperature cooling. According to latter authors, the subsequent disappearance of this cold water species may be related to consistent warming. The HO of P. grallator, recorded in the uppermost Maastrichtian in the Tahar section, is similar to that observed previously in higher northern latitudes and in lower latitudes in northwestern Morocco (Rauscher and Doubinger, 1982) and Nigeria (Oloto, 1989). Therefore, the absence or presence and geographical distribution of this species might be related not only to the climatic conditions (sea surface temperature), but also to its extreme scarcity, unfavorable environmental conditions and oceanic paleocurrents. Deflandrea galeata (Fig. 7(A)) has a FAD in the upper Maastrichtian in many areas of the Northern Hemisphere (Herngreen et al., 1986; Schiøler and Wilson, 1993; Slimani, 1995, 2000, 2001; Schiøler et al., 1997) and is here associated with other upper Maastrichtian species. This confirms a latest Maastrichtian age for the interval from Th2 to Th7b. The presence of the global Danian markers C. cornuta (Fig. 7(K, L)), D. californicum (Fig. 7(D)), Membranilarnacia? tenella (Fig. 7(I)), and S. inornata (Fig. 7(G)), a marker of the K–Pg boundary in the Northern Hemisphere, places the 60 m-thick interval from sample Th7c to sample Th7d in the Danian (Fig. 2). Other species that have a FAD in the Danian (cf. Slimani et al., 2010: pp. 106, 108, 110; Williams et al., 2004) such as Apteodinium falax (Fig. 8(F)), Carpatella septata, Cassidium fragile (Fig. 8(D)), Eisenackia margarita (Fig. 7(M)), Kallosphaeridium parvum (Fig. 8(M)), Impagidinium maghribensis (Fig. 8(I)), Kallosphaeridium yorubaense (Fig. 8(L)), Magallanesium pilatum (Fig. 8(B)), Pterodinum cingulatum subsp. danicum (Fig. 8(J)), Pyxidinopsis ardonensis (Fig. 8(G)), Xenicodinium delicatum (Fig. 8(N)), and Ynezidinium pentahedrias (Fig. 8(H)) are restricted to this interval and corroborate the attribution to the Danian. The high abundances of the heterotrophic Senegalinium species in the interval, mainly S. bicavatum, S. laevigatum, S. microspinosum, and S. obscurum are associated with elevated nutrient and productivity levels characteristic for the Danian (Brinkhuis and Zachariasse, 1988; Eshet et al., 1992; Firth, 1993; Nøhr-Hansen and Dam, 1997; Slimani et al., 2010), and support indirectly a Danian age for this interval. Other species such as Lejeunecysta izerzenensis (Fig. 8(A)), Riculacysta shauka (Fig. 7(F)), Spiniferella cornuta subsp. kasira (Fig. 8(C)) have been recorded from Maastrichtian–Danian sediments (Slimani et al., 2008, 2010, 2012; Slimani and Toufiq, 2013; M’Hamdi et al., 2013) and are observed in the same interval in the Tahar section. Thus, the K–Pg boundary lies in the 8 m-thick interval from sample Th7b to sample Th7c, above the HO of the Cretaceous taxa (Dinogymnium spp., P. cretaceum) and below the LO of the Danian markers (D. californicum, Membranilarnacia? tenella). The clayey marls (1 m-thick) located between samples Th7b and Th7c may correspond to the basal Danian. A similar lithological unit commonly called the ‘‘K–Pg boundary clay’’ marks the basal Danian in several other K–Pg boundary reference sections (Smit, 1999; Keller et al., 2002; Arenillas et al., 2006). This boundary clay was deposited during a global decrease in ocean productivity after the meteorite impact (Hsu¨ and McKenzie, 1985; Arenillas et al., 2006). In summary, the Maastrichtian and Danian stages are recognized for the first time in this region based on dinoflagellate cyst biostratigraphy, within the marly succession previously assigned to the Upper Cretaceous or Senonian. The K–Pg boundary is now determined at  220 m below the top of this marly

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succession (Fig. 2). Consequently, an important,  220 m-thick interval of sediments previously attributed to the Upper Cretaceous can now be reassigned to the Paleocene. The new species N. silsila Gue´de´ and Slimani (Figs. 3–5) and P. ayachensis Gue´de´ and Slimani (Fig. 6) show a restricted but regular presence throughout the Upper Maastrichtian (Fig. 2). N. silsila nov. sp. is common to frequent and P. ayachensis is common. Their highest occurrence lies in the uppermost Maastrichtian sample Th7b.

6. Conclusions The Upper Cretaceous to lower Paleocene marly succession of the Tahar section near Arba Ayacha in the western External Rif, northwestern Morocco, contains rich and well-preserved palynomorph assemblages. Dinoflagellate cyst biostratigraphy in this section allows the determination of a more precise age for the marls, which were previously assigned to the Senonian or Upper Cretaceous. The dinoflagellate cysts indicate a latest Maastrichtian age for the 170 m-thick interval from samples Th2 to Th7b (Fig. 2). The age determination is based on global Maastrichtian dinoflagellate cyst events such as the FAD of D. carposphaeropsis, G. perforata, and M. seelandica, and the LAD of Dinogymnium spp., I. cooksoniae, and P. cretaceum. A Danian age is proposed for the 60 m-thick interval from samples Th7c to Th7d, based on the occurrence of global Danian markers such as the FAD of C. cornuta, D. californicum, Membranilarnacia? tenella, and S. inornata. The Cretaceous–Paleogene boundary is now estimated to lie  220 m below the top of the marly succession, previously assigned to the Upper Cretaceous or Senonian. Therefore, an important  220 m-thick interval of sediments previously attributed to the Upper Cretaceous is here reassigned to the Paleocene. The new age attributions are of significance for understanding the regional stratigraphy, as the corresponding lithological units may allow interregional correlation with appropriate units at least across the occidental Rif. The dinoflagellate cyst taxonomy revealed two previously undescribed gonyaulacoid dinoflagellate cysts which are formally described in this work: Nematosphaeropsis silsila Gue´de´ and Slimani nov. sp. and Pterodinium ayachensis Gue´de´ and Slimani nov. sp. N. silsila nov. sp. is recorded for the first time from the Upper Maastrichtian, whereas P. ayachensis nov. sp. was already reported from Upper Maastrichtian, Danian and Selandian levels by several authors under open nomenclature as Pterodinium? sp. C (Schiøler and Wilson, 1993). Acknowledgements The authors thank the Research Unit Palaeontology, Ghent University (Belgium) and the Laboratory of Geology and Remote Sensing, Scientific Institute, University Mohammed V-Agdal (Morocco) for their technical support. KEG thanks the ‘‘Comite´ d’Entraide International’’ (CEI) and the ‘‘Direction de l’Orientation et des Bourses’’ (DOB) of Coˆte d’Ivoire for financial support during this study which is part of his Ph.D. thesis. The authors from the Moroccan Scientific Institute acknowledge support from the National Center of Scientific and Technical Research (CNRST; research unit URAC 46) and the University Mohammed V-Agdal (Project SVT11/09). Prof. A. Gautier from the Research Unit Palaeontology of Ghent University kindly helped putting together the final version of the manuscript. Constructive reviews by journal reviewers Drs. Edwige Masure, Fabienne Marret and Vanessa Clare Bowman are greatly appreciated.

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Appendix A Lists of dinoflagellate cyst taxa, arranged alphabetically by genera. Taxa are followed by their taxonomic junior synonym (TJS), their LO–HO interval in the studied section, their global FAD–LAD interval, and figure references in this paper within brackets, successively. The global ranges of these taxa are based on most references cited in the text and on Wrenn (1988), Head and Norris (1989), Powell (1992), Williams et al. (1993), Zevenboom (1995), Stover et al. (1996) and Williams et al. (2004). The nomenclature follows Dinoflaj2 (Fensome et al., 2008), Willumsen (2004) and Slimani et al. (2008, 2010, 2012). List 1. Selected dinoflagellate cyst taxa found in the Upper Cretaceous–lower Paleocene succession (western External Rif, Morocco).



 Apteodinium fallax (Morgenroth, 1968) Stover and Evitt, 1978; LO–HO: Danian, FAD–LAD: upper Maastrichtian–Danian (Figs. 2 and 8(F))  Carpatella cornuta Grigorovich, 1969; LO–HO: Danian, FAD–LAD: Danian–Selandian (Figs. 2 and 7(K, L))  Carpatella septata Willumsen, 2004; LO–HO: Danian, FAD–LAD: late Maastrichtian–Danian (Fig. 2)  Cassidium fragile (Harris, 1965) Drugg, 1967; LO–HO: Danian, FAD–LAD: Danian–Ypresian (Figs. 2 and 8(D))  Damassadinium californicum (Drugg, 1967) Fensome et al., 1993; TJS: Danea mutabilis Morgenroth, 1968; LO–HO: Danian, FAD– LAD: Danian–Thanetian (Figs. 2 and 7(D))  Deflandrea galeata (Lejeune-Carpentier, 1942) Lentin and Williams, 1973; LO–HO: upper Maastrichtian, FAD–LAD: late Maastrichtian–Selandian (Figs. 2 and 7(A))  Dinogymnium acuminatum Evitt et al., 1967; TJS: Dinogymnium kasachstanicum (Vozzhennikova, 1967) Lentin and Williams, 1973, Dinogymnium microgranulosum Clarke and Verdier, 1967; LO–HO: upper Maastrichtian, FAD–LAD: Turonian–late Maastrichtian (Fig. 8(E))  Dinogymnium spp. Evitt et al., 1967; FAD–LAD: Turonian–late Maastrichtian  Disphaerogena carposphaeropsis Wetzel, 1933; TJS: Cyclapophysis monmouthensis Benson, 1976; LO–HO: upper Maastrichtian– Danian, FAD–LAD: late Maastrichtian–Selandian (Figs. 2 and 7(H))  Eisenackia margarita (Harland, 1979) Quattrocchio and Sarjeant, 2003; TJS: Alisocysta rugolirata Damassa, 1979; LO–HO: Danian, FAD–LAD: Danian–Thanetian (Figs. 2 and 7(M))  Glaphyrocysta perforata Hultberg and Malmgren, 1985; LO–HO: upper Maastrichtian–Danian, FAD–LAD: late Maastrichtian– Danian (Figs. 2 and 7(E))  Impagidinium maghribensis Slimani et al., 2008; LO–HO: Danian, FAD–LAD: Danian (Figs. 2 and 8(I))  Isabelidinium cooksoniae (Alberti, 1959) Lentin and Williams, 1977; LO–HO: upper Maastrichtian, FAD–LAD: Turonian–late Maastrichtian (Figs. 2 and 7(C))  Kallosphaeridium parvum Jan du Cheˆne, 1988; LO–HO: Danian, FAD–LAD: Danian (Figs. 2 and 8(M))  Kallosphaeridium yorubaense Jan du Cheˆne and Adediran, 1985; LO–HO: Danian, FAD–LAD: Danian–Ypresian (Figs. 2 and 8(L))  Lejeunecysta izerzenensis Slimani et al., 2008; LO–HO: upper Maastrichtian–Danian, FAD–LAD: late Maastrichtian–Danian (Figs. 2 and 8(A))  Magallanesium pilatum (Stanley, 1965) Quattrocchio and Sarjeant, 2003; LO–HO: Danian, FAD–LAD: Danian–Thanetian (Figs. 2 and 8(B))  Manumiella seelandica (Lange, 1969) Bujak and Davies, 1983; TJS: Manumiella druggii (Stover, 1974) Bujak and Davies, 1983 and



     

   

Isabelidinium tingitanense Rauscher and Doubinger, 1982; LO–HO: upper Maastrichtian–Danian, FAD–LAD: late Maastrichtian–Selandian (Figs. 2 and 7(B)) Membranilarnacia? tenella Morgenroth, 1968; LO–HO: Danian, FAD–LAD: Danian (Figs. 2 and 7(I)) Nematosphaeropsis silsila Gue´de´ and Slimani sp. nov.; LO–HO: upper Maastrichtian (Figs. 2 and 3(A-L), 4(A, B), 5) Palynodinium grallator Gocht, 1970; LO–HO: upper Maastrichtian, FAD–LAD: late Campanian–Danian (Figs. 2 and 7(J)) Pterodinium ayachensis Gue´de´ and Slimani sp. nov.; LO–HO: upper Maastrichtian (Figs. 2 and 6(A–P)) Pterodinium cingulatum subsp. danicum Jan du Cheˆne, 1988; LO– HO: Danian, FAD–LAD: Danian (Figs. 2 and 8(J)) Pterodinium cretaceum Slimani et al., 2008; LO–HO: upper Maastrichtian, FAD–LAD: late Maastrichtian (Figs. 2 and 8(K)) Pyxidinopsis ardonensis Jan du Cheˆne, 1988; LO–HO: Danian, FAD–LAD: Danian (Figs. 2 and 8(G)) Riculacysta shauka Slimani et al., 2012; LO–HO: upper Maastrichtian. FAD–LAD: late Maastrichtian (Figs. 2 and 7(F)) Senoniasphaera inornata (Drugg, 1970) Stover and Evitt, 1978; LO–HO: Danian, FAD–LAD: Danian (Figs. 2 and 7(G)) Spiniferella cornuta subsp. kasira Slimani et al., 2012; LO–HO: Danian, FAD–LAD: late Maastrichtian–Danian (Figs. 2 and 8(C)) Xenicodinium delicatum Hultberg, 1985; LO–HO: Danian, FAD– LAD: Danian (Figs. 2 and 8(N)) Ynezidinium pentahedrias (Damassa, 1979) Lucas-Clark and Helenes, 2000; LO–HO: Danian, FAD–LAD: early Paleocene (Figs. 2 and 8(H))

List 2. Dinoflagellate cyst species used to compare the new species Nematosphaeropsis silsila Gue´de´ and Slimani and Pterodinium ayachensis Gue´de´ and Slimani (see Fig. 5 for Nematosphaeropsis species).  Nematosphaeropsis balcombiana Deflandre and Cookson, 1955; FAD–LAD: Ypresian–Serravallian  Nematosphaeropsis crassimuratus Strauss et al., 2001; FAD–LAD: Serravallian–Messinian  Nematosphaeropsis densiradiata (Cookson and Eisenack, 1962) Stover and Evitt, 1978; FAD–LAD: Cenomanian  Nematosphaeropsis downiei Brown, 1986; FAD–LAD: Aquitanian– Serravallian  Nematosphaeropsis labyrinthus (Ostenfeld, 1903) Reid, 1974; FAD–LAD: Rupelian–Holocene  Nematosphaeropsis lativittata Wrenn, 1988; FAD–LAD: Messinian–Gelasian  Nematosphaeropsis lemniscata Bujak, 1984; FAD–LAD: Chattian– Holocene  Nematosphaeropsis major Head et al., 1989; FAD–LAD: Tortonian–Messinian  Nematosphaeropsis oblonga Mudie, 1987; FAD–LAD: Messinian– Zanclean  Nematosphaeropsis philippotii (Deflandre, 1947) De Coninck, 1969; TJS: Nematosphaeropsis delicata Wilson in Slimani, 1994; FAD–LAD: Coniacian–Maastrichtian  Nematosphaeropsis reticulensis (Pastiels, 1948) Sarjeant, 1986; FAD–LAD: Ypresian–Lutetian  Nematosphaeropsis rigida Wrenn, 1988; FAD–LAD: Rupelian– Holocene  Nematosphaeropsis scala Duxbury, 1977; FAD–LAD: Valanginian– Hauterivian  Nematosphaeropsis singularis Davey, 1979; FAD–LAD: Aptian–Albian  Nematosphaeropsis?wrennii McMinn, 1992; FAD–LAD: Messinian  Pterodinium agadirense Below, 1981; FAD–LAD: Aptian

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 Unipontidinium aquaeductus (Piasecki, 1980) Wrenn, 1988; FAD–LAD: Serravalian  Unipontidinium grande (Davey, 1975) Wrenn, 1988; FAD–LAD: ?Campanian

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