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This paper examines the uppermost Sinemurian and lowermost Pliensbachian ammonite fauna recorded in NW Iberia with a special focus on Echioceratidae from the Aplanatum Subzone. In total, 852 specimens have been collected bed-by-bed from five reference sections from the Asturian, Basque-Cantabrian, and Lusitanian basins. Echioceratidae, namely Paltechioceras genus, represent 86.2% of the sample, Polymorphitidae (Leptonotoceras genus) the 10%, and less than 4% of the specimens are Eoderoceratidae, Phricodoceratidae, or Oxynoticeratidae. This study describes five species of Paltechioceras , namely P. tardecrescens , P. oosteri , P. recticostatum , P. elicitum , and P. romanicum. They allow a biochronostratigraphic division for the studied basins and its worldwide correlation. One of the species, P. romanicum , is the latest one registered in all the studied sections, occurring directly below the Sinemurian–Pliensbachian boundary. The disappearance of this widely distributed species marks the echioceratids extinction. This work reviews the global events described around the Sinemurian–Pliensbachian transition (the Sinemurian–Pliensbachian boundary event). Finally, we present a palaeobiogeographical analysis of the Paltechioceras species described, giving more information to discuss the opening of the Hispanic Corridor during the late Sinemurian. [ABSTRACT FROM AUTHOR]

The lower Cenomanian ammonite Sharpeiceras cf. laticlavium (Sharpe, 1855) and the middle Cenomanian ammonite Calycoceras (Gentoniceras) gentoni (Brongniart, 1822) were found for the first time in the Selbuhra Mountain section in Southwestern Crimea. These finds allow us to complete the biostratigraphic subdivision of the Cenomanian in Southwestern Crimea and to expand our understanding of the distribution of these ammonites. [ABSTRACT FROM AUTHOR]

A Cenomanian ammonite, Calycoceras (Calycoceras) naviculare (Mantell, 1822) (Acanthoceratidae, Ammonoidea) has been found in the well-known section of the Selbukhra Mountain in the vicinity of the village of Nauchnyi in southwestern Crimea. This is the first find of the ammonite in the upper Cenomanian deposits in the Crimea and in Russia. [ABSTRACT FROM AUTHOR]

A Turonian ammonite, Kamerunoceras sp. ex gr. turoniense (d'Orb.) has been found for the first time in the southwestern Crimea, in the section of the Aksu-Dere ravine, northward of the village of Kudrino (Kacha River basin). This is the first discovery of representatives of this genus in Russia. [ABSTRACT FROM AUTHOR]

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The heteromorph ammonite Pravitoceras sigmoidale with extremely twisted retroversal hook and its probable ancestors, Didymoceras awajiense and D. morozumii, occur mainly in the Upper Cretaceous Izumi and Sotoizumi groups in southwest Japan. Their morphological characteristics were investigated in this study. Morphotypes I–II were recognized in D. morozumii. Morphotypes III–V were recognized in D. awajiense. Morphotypes VI–VIII were recognized in P. sigmoidale. Moreover, all morphotypes were recognized in both the dextral and sinistral forms of these three species. Based on the morphological and stratigraphic relationships, it is considered that the evolutionary process of these species is divided into three steps: (1) shift from morphotypes I–II to III; (2) increase in variation from morphotypes III to III–V; and (3) shift from morphotypes III–V to VI–VIII. By comparing these morphotypes based on the 'growing tube model' belonging to the moving frame analysis, it is seen that there are no significant gaps of coiling patterns in the evolutionary processes of this lineage. Meanwhile, morphotypes III–V of D. awajiense have a larger morphological variation than morphotypes I–II of D. morozumii and morphotypes VI–VIII of P. sigmoidale. These results, and the radiometric ages from previous studies, suggest that D. awajiense, with considerable variation between ancestor and descendant species, existed in a short interval. It seems that P. sigmoidale occurred after the continuous but rapid and drastic morphological evolution from D. morozumii via D. awajiense. [ABSTRACT FROM AUTHOR]

In the Lower Campanian, Pachydiscus (Pachydiscus) launayi (De Grossouvre) was found for the first time above a soap (bentonite) clay layer, which has been described well in the literature, in an abandoned quarry on the outskirts of Kudrino village in Southwestern Crimea. This finding expands our understanding of the distribution of this species and precises the biostratigraphic position of the soap clay layer. [ABSTRACT FROM AUTHOR]

Introduction Hosein Abad section, with a thickness of 90 meters, is located in the structural zone of KopetDagh near the border of the North Khorasan and Golestan provinces. Stratigraphically and paleontologically, it has been done on different formations of the KopetDagh basin, including the Sarcheshmeh Formation. However, detailed stratigraphic and fossil studies are still underway due to the stratigraphic features of the KopetDagh basin and various lateral changes in the formations in this basin. Are associated with importance. Biostratigraphy using Ammonites from Sarcheshmeh Formation in the Hosein Abad section has been studied. The KopetDagh Basin was formed as an intracontinental basin in northeastern Iran after the closure of the Hercynian Ocean that followed the Early Kimmerian orogeny (Berberian and King, 1981). From the Jurassic through Eocene, relatively continuous sedimentary succession forms five major transgressive-regressive sequences in the eastern KopetDagh. Fault-controlled subsidence of the KopetDagh Basin started in the late mid-Jurassic (and terminated in the Oligocene, causing the deposition of up to 10km thick sedimentary succession (Berberian and King, 1981). Materials and Methods This research has been conducted according to field, laboratory, and office studies. Through field studies, the stratigraphic features of the Sarcheshmeh Formation, including the material and thickness of the layers, were harvested. In addition, 21 samples of ammonites were collected from the base and top of the formation after washing. Then, samples were carefully examined to determine the genus and species. To determine the age and compatibility of biozones, Reboulet et al. (2009), biozonation, which has conducted a comprehensive study in the Mediterranean basin, has been used and equated. The study also identified biozones with other studies, such as Raisosadat et al. (2011) and Kotetishvili et al. (2000) have been compared in the KopetDagh and Caucasus basins (Mediterranean). Stratigraphy Sarcheshmeh Formation is 90 meters in thickness in the Hosein Abad section. From the base, this Formation consists of 40 m alternating grey to green marls and thin to medium muddy limestone. In this sequence, 10 m of medium-bedded limestone is placed, and 40 m of marl and muddy limestone are re-deposited. The lower boundary of the Sarcheshmeh Formation is composed of thick limestone of the Tirgan Formation beds. Also, the shale and silt deposits of the Sanganeh Formation have covered the upper boundary of the Sarcheshmeh Formation. Biostratigraphy Based on different references, ten species belonging to 4 genera were identified, and the stratigraphic range chart of the ammonites in the Sarcheshmeh Formation, Hosein Abad section, was determined. These are: Pedioceras sp., Deshayesitesconsobrinus, Prodeshayesiteslestrangei, Deshayesitesaff. topleyi, Deshayesitesdeshayesi, Dufrenoyiaformosa, Deshayesitesgrandis, Dufrenoyia sp., Deshayesites sp., Prodeshayesitesgermanicus, Deshayesitesinvolutus, Prodeshayesitesaff. jacksoni, Dufrenoyiamackesoni, Deshayesitesmirabilis. For Sarcheshmeh Formation in the Hosein Abad section and based on the stratigraphical distribution of ammonites, three biozones are proposed: - Deshayesitesconsobrinus This zone is introduced locally for the first time in this study, and it can be considered a Range-zone characterized by the first and last appearance of Deshayesitesconsobrinus. The thickness of this zone is 27 meters, and it starts from the base oftheSarcheshmeh Formation. Accompanying species of this zone include: Pedioceras sp., Prodeshayesiteslestrangei, Deshayesitesaff. topleyi. The identified biological zone could be equivalent to the DeshayesitesWeissi biological zone introduced by Reboulet et al. (2009). According to a 2009 study by Reboulet et al., The relative age of this zone can be attributed to the former Aptian. - Deshayesitesdeshayesi This 40 m thick zone (layers 27 to 67 m) begins with the first presence of Deshayesitesdeshayesi index species and includes marl deposits and muddy limestone from Sarcheshmeh Formation. Fossils associated with this biological zone include: Dufrenoyiaformosa, Deshayesitesgrandis, Dufrenoyia sp., Deshayesites sp., Prodeshayesitesgermanic us, Deshayesitesinvolutus, Prodeshayesitesaff. jacksoni. According to a 2009 study by Reboulet et al., The relative age of this zone can be attributed to the upper parts of the former Aptian. - Dufrenoyiamackesoni This biozone is also proposed locally for the first time in this study as the first emergence of Dufrenoyiamackesoni. The only associated species identified in this biological zone is Deshayesitesmirabilis. This zone is 23 meters thick (layers 67 to 90 meters) and includes marl deposits and clay-limestone from Sarcheshmeh Formation. The identified biological zone could be equivalent to the Dufrenoyiafurcate biological zone introduced by Reboulet et al. (2009). According to a 2009 study by Reboulet et al., The relative age of this zone can be attributed to the late Early Aptian. 5-Comparison of identified biozones with some previous studies Due to the stratigraphic status of the biozones identified in the study of Kotetshivilii et al. (2000), the biological zone of Deshayesitesconsobrinus is equivalent to the upper part of the zone of Deshayesitesweissi-Prochelonicerasalbrechti-austriae. Furthermore, other zones separated in this study, including Deshayesitesdeshayesi and Dufrenoyiamackesoni, are comparable to the zones introduced by Deshayesitesdeshayesi and Dufrenoyiafurcata by Kotetshivilii et al. (2000). In the Mediterranean basin, Reboulet et al. (2009) equated the two habitats of Deshayesitestuarkyricus and Deshayesitesweissi with the habitat of Deshayesitesweissi-Prochelonicerasalbrechti-austriae. In this study, the Deshayesitesconsobrinus zone can be considered equivalent to the Deshayesitesweissi zone. The other zones introduced by Reboulet et al. (2009) align with the Kotetshivilii et al. (2000) study. The Dufrenoyiamackesoni biozone identified in this study can be compared to the Dufrenoyia sp. The Deshayesitesconsobrinus zone can also be considered equivalent to the Deshayesitesweissi zone. In this study, the Deshayesitesdeshayesi zone is similar to previous studies regarding stratigraphic status. Conclusion A stratigraphic section with a thickness of 90 m was selected to determine the relative age of the deposits of the Sarcheshmeh Formation in the Hosseinabad section. Based on the stratigraphy of ammonites, three biological zones, Deshayesitesconsobrinus, Deshayesitesdeshayesi, and Dufrenoyiamackesoni, were selected for Sarcheshmeh Formation, and the zones Deshayesitesconsobrinus and Dufrenoyiamackesoni were reported locally for the first time in this study. The zones introduced confirm late Late Aptian. Furthermore, a comparison of the biozones in this study with some previous studies in the KopehDagh and Mediterranean basins indicates a good correlation with other biological zones of the Aptian. [ABSTRACT FROM AUTHOR]

Among the thousands of artifacts recovered in 1891–1892 from Mound 25 of the Middle Woodland Hopewell Mound Group in Ross County, Ohio, is a Cretaceous scaphitid ammonite fossil. We have identified the ammonite as Hoploscaphites brevis, a well-known and well-studied index fossil used to subdivide the Upper Cretaceous deposits of the western interior of North America into biostratigraphic zones. The North American extent of this species is limited to parts of the Northern Great Plains, with the probable source of the Hopewell Mound Group specimen being the Sage Creek area in Pennington County, South Dakota. This probable source area for the fossil is consistent with that proposed by Charles Willoughby in the late 1800s. Both ethnological information and archaeological data, including from sites contemporaneous with Mound 25, indicate that ammonite fossils were highly prized among the people of the Northern Great Plains for curing the sick and bringing success in hunting, war, and other endeavors. Conversely, both ethnological information and archaeological data from Eastern Woodland cultures indicate ammonite fossils did not have the same allure among Eastern Woodland people. This and other information suggest that the Hopewell Mound Group ammonite fossil was indirectly procured through interaction with people living in the area where it originated. [ABSTRACT FROM AUTHOR]

Careful preparation released an ammonite specimen from a block of highly indurated sandy limestone from the oyster bed of the Wanderfeld IV occurrence in Namibia. This find is important because Wanderfeld IV is one of two known marine onshore Cretaceous deposits on the west coast of Africa south of Angola. Although ammonites often permit precise dating of the beds in which they occur, the specimens from Wanderfeld IV are placenticeratids, most of which have low stratigraphic value because of the slow evolutionary changes that lineages in this family underwent and the provincialism that it shows. This is rather unusual among ammonites and thus, based solely on its ammonite record, the Wanderfeld IV site cannot be dated more precisely than probably Cenomanian to Coniacian. However, the accompanying bivalve fauna consists of rare Protocardia umkwelanensis and abundant Rhynchostreon suborbiculatum, which gives its name to the oyster shell bed. Based on the bivalves, the Wanderfeld IV occurrence is likely to be Cenomanian. Rare microfossils from the same blocks of rock as the macrofossils did not yield precise stratigraphic information. The Wanderfeld IV deposit is a bioclastic sandy limestone, representing a fully-marine, near-shore, high energy depositional environment as indicated by the presence of immature angular quartz grains in it. There are also a few well-rounded centimetric quartz pebbles in the limestone. [ABSTRACT FROM AUTHOR]

A newly discovered ammonite of the genus Hyperlioceras from the Lincolnshire Limestone Formation of Eastern England enables the biostratigraphical position of the principal building stone of Lincoln Cathedral: the 'Silver Bed' variant of Lincoln Stone (Lower Lincolnshire Limestone) to be precisely dated as subsectum biohorizon of the Lower Bajocian, Discites Zone. Ammonites are extremely rare in this formation thus the impetus to record it here and provide a firm date for strata in which it occurred following its discovery. The lithostratigraphical provenance of the specimen is briefly discussed and evidence provided to support the conclusion. [ABSTRACT FROM AUTHOR]

Abstract Ammonite biostratigraphy could be used in age determination and correlation of rock units in different sedimentary basins. Qumenjan section with 125 meters thickness is mainly formed by grey sandy limestone with grey and thick-bedded limestone intercalations. The study area is located in the eastern margin of the Lut Block. For a stratigraphical study of Lower–Upper Cretaceous deposits in southwestern of Qayen area, a stratigraphic section was selected and measured. Eight ammonites, including Anisoceras, Calycoceras, Hypoturrilites, Hysteroceras, Mantelliceras, Puzosia, and Scaphites genera and thirteen representative species were identified. Based on the identified assemblage fossils and comparison with international biozones, Hysteroceras orbignyi subzone for Late Albian age, Mantelliceras mantelli biozone for the lower part of Early Cenomanian age, Mantelliceras dixoni biozone for the upper part of Early Cenomanian age, and Turrilites costatus biozone for Middle Cenomanian age is suggested. According to identified genera and species a Late Albian–Middle Cenomanian age is assigned for ammonite bearing of the section. The first occurrence of Mantelliceras mantelli is taken as the base of Cenomanian. Compression of the identified ammonites with other basins shows that the east Iran basin was a part of Tethys Realm during late Albian–middle Cenomanian. Keywords:Biostratigraphy, Ammonite, Albian, Cenomanian, Qayen, East Iran. Introduction Ammonites are one of the best macrofossils for Cretaceous biostratigraphy. The Albian and Cenomanian ammonites of Kopet Dagh and Central Iran have been studied by numerous researchers such as Seyed-Emami and Aryai (1981), Seyed-Emami (1977), Seyed-Emami, (1982), Seyed-Emami et al. (1984), Immel and Seyed-Emami (1985), Seyed-Emami and Immel (1995, 1996), Immel et al. (1997), Mosavinia et al. (2007), Mosavinia and Wilmsen (2011), Mosavinia et al. (2014), and Wilmsen et al. (2015). The Cretaceous deposits have spread in the east of Iran and in Birjand and Qayen area. These deposits have different facies. The Cretaceous rocks include conglomerate and sandstone units in the base and then changed to limestones in Late Barremain to Aptian. During Albian–Cenomanian, the depth of the sedimentary basin increased and thin-bedded limestones, marly limestones, and marls were deposited. The Lower Cretaceous succession is composed of different rock units that are outcropped in the eastern margin of Lut Block. These deposits usually start with a basal conglomerate. “Orbitolinind Limestone” is an informal name that is used for a succession containing Orbitolina limestone and marl intercalations. Aptian–Cenomanian succession mostly is composed of detrital, marl, and carbonate beds most of which are biogenic sediments deposited in carbonate platforms. Upper Cretaceous deposits are mostly widespread in Maastrichtian (Stocklin et al. 1972; Fauvelet and Eftekharnezhad 1990). Flyschiod facies are also spread with Ophiolites in Upper Cretaceous (Aghanabati2004). One of the oldest studies conducted in the east of Iran is published by Clap (1940). Several geological and paleontological studies have been done by several researchers such as Stocklin et al. (1972), Tirrul et al. (1983), Fauvelet and Eftekharnezhad (1990), Berthiaux et al. (1991), Raisossadat and Skelton (2005), Babazadeh et al. (2010), Khazaei et al. (2011), Raisossadat et al. (2016), Sharifi et al. (2016), Motamedalshariati et al. (2016), Raisossadat and Noori (2016), Latifi et al. (2018), Raisossadat et al. (2017) and Zarei et al. (2019). Despite the above-mentioned studies , there still seems the need to do more studies in paleontological fields. Ammonites are known as useful fossil groups in age determination and are used as biostratigraphical and biozonation tool for the Cretaceous deposits. The aim of this study is to provide an ammonite biozonation and a short palaeobiogeographic discussion on the Cretaceous deposits of the study area. Material & Methods Based on the geological map and field observation, a stratigraphical section was selected and measured in the southwest of Qayen and in south of the Qumenjan Village. The geographical coordinates of the base of the section are 58° 52' 11" E 33° 32' 19" N. Sixteen rock and ammonite samples were collected. Ammonites were cleaned, covered with magnesium vapor and photographed. Collected specimens were identified. The collected samples were stored in the Department of Geology, University of Birjand. Discussion of Results & Conclusion The Qumenjan section with 125 meters thickness starts with a conglomerated bed at the base, and then continues with sandy limestones. The major part including a succession of grey limestone and argillaceous limestone intercalations. In this study, the following ammonites are identified: Anisoceras plicatile, Calycoceras gentoni, Calycoceras (Newboldiceras) asiaticum, Calycoceras sp., Hypoturrilites sp < em>., Hysteroceras orbignyi, Mantelliceras dixoni, Mantelliceras saxbii, Mantelliceras mantelli, Mantelliceras cf. lymense, Puzosia (P.) sp., Scaphites sp. Based on reported microfauna (Ahrari 2009; Moloudi 2014) and identified ammonites a Late Aptian to Middle Cenomanian age is suggested for the section. Based on the identified ammonites, the following biozones is suggested for the studied section: Hysteroceras orbignyi subzone: this subzone is introduced as an index subzone for the Late Albian. Range of this zone is from the first occurrence of Hysteroceras orbignyi to the first occurrence of Mantelliceras mantelli. The associate ammonite is Puzosia sp. The thickness of this subzone is 25 meters. Mantelliceras mantelli Interval Zone: This zone is reported from south of the UK, France, Spain, and Portugal and south of Africa. Mantelliceras mantelli is discussed as index zone of Early Cenomanian. The range of this zone is from the first occurrence of Mantelliceras mantelli to the first occurrence of Mantelliceras dixoni. The associate ammonites are Hyphoplites cf. costosus, Hypoturrilites cf. gravesianus, Scaphites sp. The thickness of this subzone is 19 meters. Mantelliceras dixoni Interval Zone: This zone is an index zone for lower part of Middle Cenomanian. However, this zone could confirm Middle Cenomanian. The range of this zone is from the first occurrence of Mantelliceras dixoni to the first occurrence of Turrilites costatus. The associate ammonite is Mantelliceras cf. lymense. The thickness of this subzone is 14 meters. Turrilites costatus Interval Zone: This zone is introduced by Hancock (1991). Alabushev (1995) introduced it as a subzone. Wilmsen et al. (2007) mentioned Anisoceras plicatile and Turrilites costatus as index fossils for Acanthoceras rhotomagense Zone. Kennedy and Gale (2015) reported Calycoceras gentoni from Middle Cenomanian. Acanthoceras rhotomagense is reported as the index zone of Middle Cenomanian. In the studied section A. rhotomagense has not been reported. Therefore, based on the occurrence of Turrilites aff. costatus Zone, Middle Cenomanian age is suggested for the upper part of the section. The associate assemblages include Calycoceras (Newboldiceras) asiaticum, Calycoceras gentoni, Anisoceras plicatile and Calycoceras sp. Latitudinal and provincial control of ammonite faunas was common throughout the Mesozoic. Both the ranks (realm, province, etc.) and names have varied from author to author. Tectonic movements and sea-level changes (regressions and transgressions) caused seaways connecting basins to open marine or close and led to several distinct new basins or limitation of seaways and between marine basins. Thus, numerous sub-realms and provinces have been named. Three biogeographic realms existed during the Mesozoic; Boreal Realm embraced the Arctic basins and the seas extending southward from there over parts of North America, Northern Europe, and Siberia. The Boreal seas were largely landlocked but linked by narrow seaways to the Tethyan Realm. The Tethyan Realm includes low latitude areas such as Africa, the Pacific, the Middle East, and America, and centered on the Paleo-Tethys Ocean. An Austral Realm has also been proposed for high southerly latitudes (Stevens 1973). To study the palaeobiogeographic conditions of Upper Albian–Lower Cenomanian in eastern Iran, the ammonite fauna of the studied section was compared with other reported ammonites from different areas. The reported ammonites from east of Iran show affinity with those reported from Kopet Dagh, Central Iran, Europe, and USA. The absence of Scholenbachia that is an index genus of the Boreal Realm and the presence of some genera such as Anisoceras, Scaphites, Hypoturrilites, and Puzosia could suggest that the study area is a part of Tethys Realm. However, the presence of Mantelliceras could show the effects of the influence of Boreal. The analysis of the ammonite stratigraphic distribution in the selected section in east of Iran allowed us to establish the faunal succession for the Upper Albian–Middle Cenomanian in the region. Based on identified assemblage, the following biozones are suggested. Hysetroceras orbignyi subzone is suggested as index zone of Late Albian, Mantelliceras mantelli Zone could confirm lower part of Early Cenomanian, Mantelliceras dixoni Zone is known as the upper part of Early Cenomanian and Turrilites costatus Zone is suggested as Middle Cenomanian. Compression of the identified ammonites with other basins shows that the east Iran basin was a part of Tethys Realm during Late Albian–Middle Cenomanian.

In the first section I analyse anthroponyms which are written Šby, Š(w)by and Šbᵓ in Hebrew and Aramaic. In the second section I argue that Ḥnnh/Ḥnwnh on Yhwd-impressions refers to a male rather than a female functionary (or functionaries). [ABSTRACT FROM AUTHOR]

This paper attempts a synthesis of the evolution of large pelagic filter-feeding animals from the Cambrian to the present. Lineages known or suspected to have evolved large pelagic filter-feeding species are, in the order of their appearance, stem euarthropods, agnathan fishes, nautiloid cephalopods, placoderms, sharks, bony fishes, reptiles, ammonite cephalopods, and mammals. I discuss evolutionary trends which are apparent from the evolution of the large pelagic filter-feeding niche, which are 1. a size increase relative to their ancestral species, 2. the transition between taxonomic groups giving rise to pelagic filter-feeders, with vertebrates dominating the post-Cambrian, 3. the evolution of large pelagic filter-feeders from large carnivores in most, but not all cases, and 4. lengthy gaps in the record of pelagic filter-feeders around four of the big five mass extinctions. [ABSTRACT FROM AUTHOR]

The Belize Basin in southern Belize, Central America, contains numerous seepage oils derived from marly and carbonate source rocks, but since no definitive source rocks have been identified the source remains uncertain. This study examines by pyrolysis and organic petrography the source rock quality and maturity of 66 samples collected from three newly exposed carbonate sections in the southeastern Belize Basin together with organic geochemical analysis of five new occurrences of seepage oils from the southern Belize Basin. Combined ammonite and aptychi biostratigraphy suggest a Berriasian to Hauterivian age of the source rock samples. Low T max values show the samples are thermally immature. Numerous samples are oil-prone and have Hydrogen Index values >300–400 mg HC/g TOC, reaching a maximum of 768 mg HC/g TOC. The samples with source rock potential contain from 32 to 64% pyrolysable organic carbon and contains liptinite-rich Type II kerogen consisting of alginite, bituminite, and liptodetrinite. The calculated Ultimate Expulsion Potential (UEP) of a 22.5 m thick section amounts to ∼2.5 mmboe/km2. This generation capacity is volumetrically relatively small, but it could be compensated for by a thicker source rock section. However, the identified source rocks could account for the seepage oils in the Belize Basin, and they are thus the first documentation of Lower Cretaceous source rocks in Belize. A plausible explanation for the widespread occurrence of seepage oils in the Belize Basin could be generation from organic-rich layers with bituminite and alginite. In line with this and previously examined seepage oils, the new variably degraded oils were sourced from carbonate source rock facies. • First documentation of Lower Cretaceous carbonate source rocks in the Belize Basin • The source rocks are oil-prone and have Hydrogen Index values >300–400 mg HC/g TOC, reaching a maximum of 768 mg HC/g TOC • The Type II kerogen consists of alginite, bituminite, and liptodetrinite with 32–64% of the carbon being pyrolysable • Five new seepage oils are variably degraded and were sourced from a carbonate source rock facies • The source rocks are thermally immature but the seepage oils could be generated from similar mature carbonate facies [ABSTRACT FROM AUTHOR]

The Kopet Dagh sedimentary basin is situated in the northeast of Iran and the south of Turkmenistan. The present work focuses on the systematic representative's species of the Family Phylloceratidae Zittel, 1884, of the Family Gaudryceratidae Spath 1927, of the Family Oppeliidae H. Douvillé, 1890, and of the Family Desmoceratidae Zittel, 1895, all of which are for the first time in the basin. Based on previous studies and assemblage fauna in this study, a late Barremian-early Aptian age is suggested for the measured sequences. The palaeobiogeographical distribution of the ammonites indicates that during the late Barremian to the late Aptian the basin formed part of the Tethyan realm, Mediterranean-Himalayan Province. The studied fauna and other reported ammonites in previous publication might suggest nearshore to offshore an epipelagic to pelagic environment. There is also a relation between the lithology and the morphotype of ammonites. [ABSTRACT FROM AUTHOR]

Methane seeps were a common feature in the Late Cretaceous Western Interior Seaway of the United States. We document the occurrence of methane seep deposits in the Pierre Shale on the Cedar Creek Anticline in east‐central Montana for the first time. The seep deposits occur in the lowermost part of the Baculites baculus Zone (the Endocostea typica Zone), corresponding to the lowermost Maastrichtian. They are therefore the youngest seeps yet described from the Western Interior Seaway. We conducted a detailed faunal analysis of a single seep deposit, together with geochemical investigation of both seep carbonates and molluscan shell material to determine palaeoenvironmental conditions. Oxygen isotope analysis of well‐preserved molluscan shell material reveals water temperatures of between 19 and 27°C, while depleted carbon isotope values of seep carbonates are indicative of the anaerobic oxidation of methane. The morphology of the seep deposit suggests a strong advective flux of methane to the sediment–water interface. Comparison to a nearby contemporaneous non‐seep site reveals that similar groups of organisms occur in both settings, albeit with varying relative abundances – the seep is numerically dominated by the lucinid bivalve Nymphalucina occidentalis. Substrate appears to be the major control on the diversity and palaeoecological composition of both seep and non‐seep sites. [ABSTRACT FROM AUTHOR]

• We document a new collection of latest Albian ammonites from Salazac (Gard, France). • The collection includes 564 studied specimens. • 38 taxa (25 genera) of ammonites are described. • Our work emphasizes the remarkable richness of the ammonite diversity from Salazac. The Salazac locality (Gard, southeastern France) is renowned for the richness of its cephalopod fauna (especially ammonites) from the Mortoniceras fallax Zone (uppermost Albian, Lower Cretaceous). However, most ammonite species have paradoxically been scarcely illustrated up to now. Furthermore, the rare assessments of ammonite taxonomic diversity are presumably inaccurate, as they either result from a drastic typological approach or could not benefit from the most recent advances in modern concepts of ammonoid intraspecific and ontogenetic variations. In this work, we document an original cephalopod assemblage from Salazac represented by abundant, well-preserved specimens (564 studied ammonites, including ca. 50% of heteromorphs) constituting a high diversity. The sample size and quality of this new material allowed some extensive morphological and biometric analyses whenever possible (i.e., for subdatasets in which a significant number of measurements is available) and to thoroughly assess intraspecific and ontogenetic variations for a few species. This led to determine the diagnostic value of various shell characters commonly used to characterize both well-documented and poorly-defined species. In particular, we show that a significant part of the variation in the number of ribs per whorl within the heteromorphic genera Mariella and Turrilitoides is directly related to shell size and that the strength of tubercles covaries negatively with the number of ribs in Mariella , therefore challenging the diagnostic value of these characters. We further suggest that rib density covaries with whorl shape in Mariella , following Buckman's first rule of covariation. In total, one species of nautilid and 38 taxa (25 genera) of ammonites are described, among which five species are documented from Salazac for the first time. In turn, this study provides valuable data for future phylogenetic, biostratigraphical, biogeographical and broad-scale diversity studies. [ABSTRACT FROM AUTHOR]

The Aptian deposits on Spitsbergen Island are poorly studied. Moreover, there were no published data on fossil distribution in the Aptian and Albian in the vicinity of the town of Longyearbyen. This article provides new data on ammonite-based biostratigraphy of the Carolinefjellet Formation, indicating the presence of Beds with Tropaeum arcticum (middle Aptian) and Beds with Grantziceras (lower Albian). The age of the formation was verified and the presence of lower Albian strata was justified. The results of microscopic and isotope studies of five samples of glendonites collected from the middle Aptian of the Carolinefjellet Formation section are presented. Glendonites from the Carolinefjellet Formation are composed of three calcite phases: ikaite-derived calcite and two successive types of cement, which fill cavities and develop partially after the first-phase calcite. The O and C isotope compositions of glendonites were measured in five bulk samples from the middle Aptian interval of the section. The δ18O isotope composition of glendonites is significantly different from that of seawater, indicating the input of diagenetic fluids; the δ13C values are characteristic of sedimentary organic matter and methanotrophy. For the first time, findings of ammonites allowed us to clarify the stratigraphic intervals of glendonite occurrence and associated cold-climate episodes and prove the early Albian age of glendonites from the top of the Carolinefjellet Formation. [ABSTRACT FROM AUTHOR]

In the last few decades, hook‐like structures have been reported in the Mesozoic ammonite family Scaphitidae. Despite their exceptional preservation and debates about their function, no detailed reconstruction has been available until now. For the first time, we describe the composition and details of the morphology of these structures found in the body chambers of six specimens of the Campanian ammonite Rhaeboceras halli (Meek & Hayden) using high resolution x‐ray imaging. The hook‐like structures are composed of a thin layer of brushite. The base of each hook is open on one side forming an internal cavity, now filled with sediment. The tips of the hooks end in one or two cusps or, rarely, exhibit a blunt end. We used geometric morphometrics to capture the morphological disparity of the bicuspidate morphotypes comprising 98% of the hooks. Principal component analysis revealed chirality among the hooks and a cluster analysis recognized five morphologies. Contrary to the previous interpretation of these structures, we conclude that they are not radular teeth. They are much larger and more variable in size and shape than any known ammonite radulae and completely out of proportion with respect to the size of the jaw. The chirality, the hook‐like shape, and the absence of a size relationship between the hooks and the body chambers in which they occur, lead us to propose that these hooks could represent elements of the brachial crown related to copulatory behaviour. If so, these would be the first reported remnants of brachial crowns in ammonites. [ABSTRACT FROM AUTHOR]

About 12000 Early Cretaceous invertebrate fossils - mainly ammonites - were collected in the early 1960s in Bersek Hill (Gerecse Mountains, Hungary). The collecting was supervised by the late professor József Fülöp, that time head of the Hungarian Geological Institute. The scientific study of this large fossil material started only more than 30 years later, after the death of the professor. According to the decision of the the Institut's board of directors the fossils were transferred and deposited in the public collection of the Palaeontological and Geological Department of the Hungarian Natural History Museum. Considering the request of the board of directors the collection was informally named as „Fülöp József Collection“. However the ownership of the fossils, which were collected during the project of the Hungarian Geoglogical Institution, was debated by the professor's family. Another complication was that the original field notes of the one-time collecting campaign was not available, and in the lack of this documentation the scientific evaluation of the collection seemed to be impossible. Finally after a careful work in the collection and also in the field, using the indicated bed numbers below the fossil specimens as a clue and starting point, it was possible to reconstruct the location and the bed numbering system of the collectors. The Fülöp József Collection was studied by an international team ofgeoscientist, and after an intensive research the palaeontological, stratigraphical and geochemical results were published in a series of scientific papers. By now, due to the many sided results based on the study of the Fülöp József Collection, the biostratigraphically well-documented succession of the Bersek Hill serves as a key section for the Mediterranean Lower Cretaceous. With three figures. [ABSTRACT FROM AUTHOR]

Ammonoid sutures are geometric patterns formed by the intersection of the septa and the shell wall, and have long been a diagnostic tool for ammonite researchers for such applications as species identification, taxonomic relationships, ontogenetic change, functional and evolutionary morphology, determination of ecological niche, and other aspects of ammonoid paleobiology. Researchers interested in a variety of paleobiological questions related to ammonoids have almost always required access to the entire hemisuture. Without access to specimens in museum or institutional collections, researchers must rely on previously published illustrations and photographs of ammonoid sutures. However, due to the perspective in photographs, distortion of the marginal elements of suture geometry occurs due to shell curvature near the venter and umbilicus when photographed in profile. The revised approach described here, which we refer to as the Lateral Lobe Saddle, or LLS approach, makes use of only the lateral lobe and second saddle S2 (lateral lobe-second saddle pairs, or LLS) which lie in the central, mid-whorl undistorted sector of a suture line as viewed in lateral, profile shell photos and illustrations. The factors by which fractal dimension of LLS data convert to fractal dimension of the standard hemisuture measurements are largely consistent within genera. The LLS method’s non-requirement of a full hemisuture also facilitates comparisons among sutures within an ontogenetic sequence, or sutures from multiple ammonite taxa where ventral and umbilical sutural elements are hidden by whorl overlap or poor preservation.

A comprehensive taxonomic account of fourteen ammonite species from the upper Albian succession of the Cauvery Basin, south India is presented. They belong to the genera/subgenera Gaudryceras , Anagaudryceras , Tetragonites , Puzosia (Puzosia), Puzosia (Bhimaites), Desmoceras (Desmoceras), Desmoceras (Pseudouhligella), Stoliczkaia (Stoliczkaia) and the heteromorphs Anisoceras and Mariella. Most of these ammonite species are cosmopolitan and well-known, especially from the western margin of the Tethys. The additional value of this study in contrast to earlier studies is founded in the intensive bed-by-bed collection from a well-documented measured section. This allows to establish a first detailed range chart for the uppermost Albian of this region and to correlate the Cauvery Basin section with the upper Albian Mortoniceras perinflatum Zone- Arrhaphoceras briacensis Zone interval of the Standard Tethyan Scheme. [ABSTRACT FROM AUTHOR]

The life histories of ammonites and the life strategies they employed are difficult to assess without robust modern analogues but placing constraints on ammonite growth rates provides a fundamental first step to understanding this abundant, but poorly understood, fossil group. Here we interpret periodic variations in carbon and oxygen stable isotope profiles from Campanian and Maastrichtian ammonites (Baculites) as seasonally driven and use these records to determine their rate of shell precipitation. Several of these samples are housed in museums and were originally prepared using sealants for display and preservation but testing of these sealants indicated no alteration of the isotopic values of treated carbonate. Diagenetic alteration, as determined by shell microstructure, affected the preservation of isotopic signals, resulting in the loss of seasonal variation in less well‐preserved specimens, and the δ13C signal is more robust than δ18O. The periodicity of isotopic profiles from Baculites shells presented here suggest that these organisms grew at rapid rates (c. 340 mm per year), which may imply an r‐type life strategy in which the animals reach maturity quickly, spawn large quantities of progeny, and die at a young age. Because of the potential mobility of Baculites, reconstructing palaeoenvironmental conditions from these isotopic records is challenging and should be conducted cautiously. Unfortunately, well‐preserved Baculites shells much longer than 350 mm are rarely recovered, which complicates the statistical treatment of potential periodicity in isotopic profiles. [ABSTRACT FROM AUTHOR]

Amber is fossilized tree resin, and inclusions usually comprise terrestrial and, rarely, aquatic organisms. Marine fossils are extremely rare in Cretaceous and Cenozoic ambers. Here, we report a record of an ammonite with marine gastropods, intertidal isopods, and diverse terrestrial arthropods as syninclusions in mid-Cretaceous Burmese amber. We used X-ray-microcomputed tomography (CT) to obtain high-resolution 3D images of the ammonite, including its sutures, which are diagnostically important for ammonites. The ammonite is a juvenile Puzosia (Bhimaites) and provides supporting evidence for a Late Albian-Early Cenomanian age of the amber. There is a diverse assemblage (at least 40 individuals) of arthropods in this amber sample from both terrestrial and marine habitats, including Isopoda, Acari (mites), Araneae (spiders), Diplopoda (millipedes), and representatives of the insect orders Blattodea (cockroaches), Coleoptera (beetles), Diptera (true flies), and Hymenoptera (wasps). The incomplete preservation and lack of soft body of the ammonite and marine gastropods suggest that they were dead and underwent abrasion on the seashore before entombment. It is most likely that the resin fell to the beach from coastal trees, picking up terrestrial arthropods and beach shells and, exceptionally, surviving the high-energy beach environment to be preserved as amber. Our findings not only represent a record of an ammonite in amber but also provide insights into the taphonomy of amber and the paleoecology of Cretaceous amber forests. [ABSTRACT FROM AUTHOR]

Two new species of stephanoceratid ammonites are erected: Stephanoceras (Riccardiceras) eoeteosum sp. nov. and Stephanoceras (Skirroceras) englandi sp. nov. from the Inferior Oolite Formation of Dorset, UK. They represent the first and last members of a chronocline of serpenticonic morphospecies. The stratigraphical position of Rhytostephanus rhytus Buckman is reviewed, necessitating a change in the faunal horizon scheme. The term mesoconch is proposed for use in describing microsomic macroconchs, the function of which is considered. Names applied to morphospecies and their uses are reviewed. The role of conservation is discussed in respect of preserving Dorset Inferior Oolite exposures. [ABSTRACT FROM AUTHOR]

The spatial scaling of 77 hemisutures from 65 species of Cretaceous heteromorphic ammonites was quantified with the fractal box‐counting method. Fractal dimensions within Baculites compressus did not significantly differ between adult hemisutures; however, the juvenile suture of this species did exhibit a significantly lower fractal dimension. This suggests that variation in sutural complexity between explicitly adult ontogenetic stages may not contribute to significant noise in comparisons between other species/morphotypes. High‐spired, three‐dimensionally coiled heteromorphs with a larger degree of septal asymmetry exhibit higher fractal dimensions in outer whorl hemisutures than inner whorl hemisutures due to their elongation and improved space occupation over a larger whorl surface. Three‐dimensionally coiled ammonites also have higher fractal dimensions on average (mean Db = 1.45) with respect to their 2‐D coiled counterparts (mean Db = 1.38). All ammonites in this study exhibit a positive trend between sutural complexity and shell size (proxied by whorl height). These relationships suggest that septal frilling is constrained by shell morphology and whorl section geometry during septal morphogenesis. This, in turn, influences the scaling, space‐filling properties and scaling limits of ammonitic suture patterns. Sutural/septal complexity is also found to positively influence the amount of liquid retained in marginal septal recesses. However, as these septa approach larger scales, less cameral liquid is retained per septal mass. This may further explain the positive relationship between sutural complexity and shell size. [ABSTRACT FROM AUTHOR]

During the recent field research on the Tirgan Formation in the west of Kopet-Dagh sedimentary basin, ammonite assemblages were obtained from the carbonate strata of this formation. This new finding is important for stratigraphical purpose. In this research, 3 genera belong to Heteroceras, Deshayesites and Cheloniceras? as well as one uncertain genus belongs to Turkmeniceras are determined. The ammonite fauna dates the Tirgan Formation from the late Barremian to early Aptian in the studied stratigraphic section. [ABSTRACT FROM AUTHOR]

Appendix: Description of a new Bajocian (Middle Jurassic) ammonite species, Cranocephalites tvaerdalensis sp.nov., from Geographical Society Ø, North-East Greenland. A new Cranocephalites species, C. tvaerdalensis sp. nov., is described. Its type locality is a restricted outcrop of the Pelion Formation in Tværdal on Geographical Society Ø, North-East Greenland. It belongs to the C. carlsbergensis group and has its type horizon in the upper Bajocian (Middle Jurassic) Pompeckji Zone.

Abstract We describe an outcrop of the Cretaceous–Paleogene (K–Pg) boundary exposed due to construction near New Albany, Union County, Mississippi. It consists of the Owl Creek Formation and overlying Clayton Formation. The Owl Creek Formation is rich in the ammonites Discoscaphites iris and Eubaculites carinatus , which, along with biostratigraphically important dinoflagellate cysts and calcareous nannofossils, indicate deposition occurred within the last 1 million years, most likely last 500 kyrs, of the Cretaceous. The base of the overlying Clayton Formation marks the K–Pg boundary, and consists of a 15–30 cm thick muddy, poorly sorted quartz sand containing abundant spherules representing ejecta derived from the Chicxulub impact event. Impact spherules range in size from 0.5 mm to 1 mm in diameter and are hollow and well preserved, with details such as smaller vesicular spherules enclosed within. The spherules are altered to clay minerals such as smectite and are typical of those found at K–Pg boundary sites in the Gulf of Mexico and beyond. Spherules are scattered throughout the bed, and surface counts suggest an average of 4 spherules per cm2. Macrofossils within the spherule bed represent a rich fauna of ammonites, benthic molluscs (bivalves and gastropods), echinoids, as well as crabs and sharks. Macrofossil preservation ranges from whole to fragmentary, with most fossils preserved as internal moulds. The infill of the fossils is lithologically identical to the matrix of the spherule bed, including impact ejecta preserved within phragmocones and body chambers of ammonites, and differs from the underlying Owl Creek Formation. This suggests that the animals were either alive or loosely scattered on the sea floor at the time of deposition. Grain size changes indicate multiple events were responsible for deposition, and together with taphonomic evidence are consistent with dynamic high energy post-impact processes. Later sea level change during the Paleocene is responsible for a sharp contact at the top of the spherule bed. Geochemical evidence from the Owl Creek and Clayton Formations at this locality indicate numerous local paleoenvironmental changes affected the Mississippi Embayment at the time of the K–Pg boundary and mass extinction event. Highlights • Describes new outcrops containing the Cretaceous–Paleogene (K–Pg) boundary from Union County, Mississippi. • The fossiliferous Owl Creek Formation contains ammonites and diverse benthic molluscan fauna. • Biostratigraphic correlation by macro and microfossils is consistent with deposition during the latest Maastrichtian. • A 15–30 cm-thick event bed with macrofossils and impact spherules occurs above the K–Pg boundary. • Spherule bed was emplaced rapidly by multiple processes following the Chicxulub impact event. [ABSTRACT FROM AUTHOR]

This work provides a new ammonite age-calibration of the rudistid limestones of the Urgonian-type Provence carbonate platform (Southeast France) based on sampling along three ∼200 km-long platform-to-basin transects and re-examination of historical collections. Ammonite key findings indicate that the first rudistid platform stage (including the Agriopleura and requieniid–monopleurid beds) develops and spreads northward through the Toxancyloceras vandenheckii – Gerhardtia sartousiana zones interval (lower upper Barremian). This stage is interrupted by the tectonically-induced deepening of the southern Provence domain during the Imerites giraudi Zone while the northern regions records the massive deposition of Palorbitolina – Heteraster beds. Recovery of the rudistid carbonate system is illustrated by the development of caprinid-bearing rudistid limestones in the North Provence domain through the Martelites sarasini Subzone (lower Martelites sarasini Zone, uppermost Barremian), which shows a bidirectional progradation toward the South Provence and Vocontian basins. The caprinid-bearing limestones terminate at a short-term exposure and are overlain by cherty–oobioclastic deposits spanning the Pseudocrioceras waagenoides Subzone (upper M. sarasini Zone) to the lower Deshayesites forbesi Zone. A regional-wide flooding of the study area is illustrated by the abrupt change to a marl-dominated regime occurring in the upper D. forbesi Zone. Compared to the previous datings, the Barremian/Aptian boundary should be relocated in the lower part of the post-caprinid, cherty–oobioclastic deposits although its precise level cannot be fixed due to the lack of a continuous ammonite record. Ammonite age-calibration of the surrounding Urgonian rudistid platform series is discussed and gives evidence of a comparable twofold demise of the peri-Vocontian rudistid biota during the uppermost Barremian. Accordingly, the link between the final demise of the peri-Vocontian rudistid biota and the onset and/or culmination of the mid-early Aptian Oceanic Anoxic Event (OAE) 1a should be reconsidered. [ABSTRACT FROM AUTHOR]

The present contribution documents the ammonite record of the La Peña Formation from the la Sierra del Patrón (Durango State, Mexico). Twenty one taxa have been recognized among the 354 specimens collected bed-by-bed. Our biostratigraphic analysis of the ammonite distribution allow us to improve the zonation for the transition of the lower/upper Aptian boundary of northeast Mexico, composed of the upper lower Aptian Dufrenoyia justinae interval Zone (including the Dufrenoyia scotti / Burckhardtites nazasensis concurrent range Subzone at its top) and the lower upper Aptian Caseyella aguilerae interval Zone (including the Gargasiceras ? adkinsi total range Subzone at its base). The lower/upper Aptian boundary is herein well characterized by means of endemic or quasi-endemic taxa and a strong ammonite faunal turnover marked by a renewal at the generic and family levels comparable with those of the Mediterranean-Caucasian regions (end of Deshayesitidae balanced by the renewal in the douvilleiceratid, desmoceratid and acanthohoplitid stocks). The proposed zonation of the Sierra del Patrón section is an important step forward in the development of the Aptian zonation for the Central Atlantic Province and its correlation with the Standard Mediterranean ammonite zonation. [ABSTRACT FROM AUTHOR]

Our data from studies over many years on upper Tithonian–Berriasian strata of the Crimean Mountains are summarised. Their zonal subdivision has been significantly refined using ammonites and foraminifera, as well as on the basis of calpionellid, ostracod and dinocyst distributions. We have been able to document the presence of all standard Tethyan zones in the Berriasian, i.e., the Jacobi, Occitanica and Boissieri Zones, identified on the basis of foraminifera, ostracods and dinocysts. Based on calpionellids (families Chitinoidellidae and Calpionellidae) in Eastern Crimea, three standard zones were identified: Chitinoidella (Dobeni and Boneti Subzones; Tithonian), Crassicollaria (Remanei and Massutiniana subzones; Tithonian) and Calpionella (Alpina and Elliptica subzones; Berriasian). Tithonian and Berriasian calpionellid assemblages were identified in Southwestern Crimea. A magnetostratigraphic scale for the upper Tithonian–Berriasian has been also developed, thus corroborating a continuous succession of magnetic chrons from M20 through M14. The existence of the M16n.1r subchron (‘Feodosiya’) is substantiated; it should be included into the Geomagnetic Polarity Time Scale. The base of polarity chron M18r appears to be the most likely choice among other palaeomagnetic intervals to determine the lower boundary of the Cretaceous System, because it is close to the base of the Grandis Subzone in Tethyan sections and the Chetae Zone in Boreal sections. [ABSTRACT FROM AUTHOR]