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Planktonic foraminiferal biostratigraphy of the Upper Barremian and Aptian of Crimea
Abstract and Figures
Reexamination of the Barremian–Aptian planktonic foraminifers from three sections (Verkhoirechie, mountain Krasnaya, and Marino) allowed the biostratigraphic scheme for Southwest and Central Crimea to be refined and updated. The following standard zones are recognized in the studied sections: Blowiella blowi (upper Barremian), Hedbergella excelsa (upper Barremian–lower Aptian), Leupoldina cabri (lower Aptian), H. luterbacheri, Globigerinelloides ferreolensis, Gl. barri, Gl. algerianus, Hedbergella trocoidea, Paraticinella rohri (upper Aptian). Beds with Hedbergella ruka are recognized in the B. blowi Zone. Foraminifers from the Partizanskoe section, representing the lower Aptian L. cabri and H. luterbacheri zones, are studied. The recognized strata are correlated with ammonite and nannoplankton zones and paleomagnetic data.
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Supplementary resource (1)
... This paper proposes the first detailed stratigraphic subdivision of the Upper Barremian (?)-Aptian deposits of this section using planktonic foraminifera (PF) and ostracods. In addition, the PF Hedbergella ruka interval-zone, which was previously recognized as beds (Brovina, 2017;Karpuk et al., 2018) is described. The Robsoniella minima-Loxoella variealveolata Zone and the Beds with Cytheropteron tesakovae, recognized using ostracods in the southwestern Crimea, have been redescribed in detail (Karpuk, 2016b;Karpuk et al., 2018). ...
... Planktonic foraminifera of the Crimea have been studied since the late 1950s. The history of the Crimean stratigraphic scheme development (Gorbachik, 1986), International stratigraphic chart (ISC) foundation (Ogg and Hinnov, 2012;Gale et al., 2020) and detailing of the international schemes by several authors (Coccioni et al., 2007;Moullade et al., 2015, a.o.) were analyzed and described by E.A. Brovina (Brovina, 2017;Brovina et al., 2017;Karpuk et al., 2018). ...
... I, figs. 9-11), which according to E.A. Brovina marks the Beds with H. ruka in Crimea (Brovina, 2017;Karpuk et al., 2018). The material available to Brovina did not allow these beds to be established as a zone, since they were found in only two sections, Verkhorechie, where the beds were recognized for the first time (Brovina, 2017), and Zavodskaya Balka, where they were identified only in one sample (Karpuk et al., 2018). ...
Planktonic foraminifera and ostracods of the upper Barremian (?)–lower Aptian of the Kokluk section (Eastern Crimea) are studied. Three interval-zones are established based on foraminifera: Globigerinelloides blowi, Hedbergella ruka and H. excelsa. Beds with H. ruka are described as a zone. Based on ostracods, Robsoniella minima–Loxoella variealveolata Zone and Beds with Cytheropteron tesakovae are determined. An interval possibly corresponding to OAE 1a is ascertained. Species C. tesakovae is described as new. The Kokluk section is correlated with coeval sections Verkhorechie (South-Western Crimea) and Zavodskaya balka (Eastern Crimea). Paleoecological analyses of the Kokluk section is made.
... This paper proposes the first detailed stratigraphic subdivision of the Upper Barremian (?)-Aptian deposits of this section using planktonic foraminifera (PF) and ostracods. In addition, the PF Hedbergella ruka interval-zone, which was previously recognized as beds (Brovina, 2017;Karpuk et al., 2018) is described. The Robsoniella minima-Loxoella variealveolata Zone and the Beds with Cytheropteron tesakovae, recognized using ostracods in the southwestern Crimea, have been redescribed in detail (Karpuk, 2016b;Karpuk et al., 2018). ...
... Planktonic foraminifera of the Crimea have been studied since the late 1950s. The history of the Crimean stratigraphic scheme development (Gorbachik, 1986), International stratigraphic chart (ISC) foundation (Ogg and Hinnov, 2012;Gale et al., 2020) and detailing of the international schemes by several authors (Coccioni et al., 2007;Moullade et al., 2015, a.o.) were analyzed and described by E.A. Brovina (Brovina, 2017;Brovina et al., 2017;Karpuk et al., 2018). ...
... I, figs. 9-11), which according to E.A. Brovina marks the Beds with H. ruka in Crimea (Brovina, 2017;Karpuk et al., 2018). The material available to Brovina did not allow these beds to be established as a zone, since they were found in only two sections, Verkhorechie, where the beds were recognized for the first time (Brovina, 2017), and Zavodskaya Balka, where they were identified only in one sample (Karpuk et al., 2018). ...
Planktonic foraminifera and ostracods of the upper Barremian(?)-lower Aptian of the Kokluk section (eastern Crimea) are studied. Three interval-zones are established based on foraminifera: Globigerinel-loides blowi, Hedbergella ruka and H. excelsa. Beds with H. ruka are described as a zone. Based on ostracods, Robsoniella minima-Loxoella variealveolata Zone and Beds with Cytheropteron tesakovae are determined. An interval possibly corresponding to OAE 1a is recognized. The species C. tesakovae is described as new. The Kokluk section is correlated with the coeval Verkhorechie (southwestern Crimea) and Zavodskaya Balka (eastern Crimea) sections. The Kokluk section is analyzed paleocologically.
... Microfossil identification was conducted using the classification systems developed by Dunham (1962) [9]). Foraminifers and calcareous algae were identified based on the methodologies outlined in publications by Premoli Silva and Verga (2004) [10], Husinec and Sokač(2006) [11], Afghah (2006) [12], Hosseini and Conrad (2008) [13], Parvaneh Nejad Shirazi (2009) [14], Schroeder et al. (2010) [15], Bucur et al. (2012) [16], Abyat et al. (2016) [17], Afghah et al. (2016) [7], Brovina (2017) [18], Coccioni (2019) [19], and Abedpour et al. (2021) [20]. Comprehensive descriptions of the samples, both from field and laboratory analyses, were meticulously recorded and integrated into a detailed stratigraphic section.This study introduces an innovative workflow designed to provide a precise and comprehensive analysis, outlined as follows: ...
... Microfossil identification was conducted using the classification systems developed by Dunham (1962) [9]). Foraminifers and calcareous algae were identified based on the methodologies outlined in publications by Premoli Silva and Verga (2004) [10], Husinec and Sokač(2006) [11], Afghah (2006) [12], Hosseini and Conrad (2008) [13], Parvaneh Nejad Shirazi (2009) [14], Schroeder et al. (2010) [15], Bucur et al. (2012) [16], Abyat et al. (2016) [17], Afghah et al. (2016) [7], Brovina (2017) [18], Coccioni (2019) [19], and Abedpour et al. (2021) [20]. Comprehensive descriptions of the samples, both from field and laboratory analyses, were meticulously recorded and integrated into a detailed stratigraphic section.This study introduces an innovative workflow designed to provide a precise and comprehensive analysis, outlined as follows: ...
The Khalij limestone member, well-known for its abundant benthic facies, is situated in the middle segment of the Gadvan shaly formation, boasting an average thickness of approximately 14 meters. This specific member is exclusively found below the surface, devoid of any exposed outcrops, and is characterized by the presence of easily identifiable orbitolinid limestone. Well logging techniques, such as Gamma Ray and Density measurements, prove particularly effective in identifying this distinct layer. The primary objective of this study was to conduct a comprehensive analysis of the lithostratigraphy and microstratigraphy within the Gadvan formation, with a specific emphasis on the Khalij limestone member. A regional stratigraphic assessment covered an extensive area of about 100,000 square kilometers in the Fars and Dezful regions within the Zagros region. To achieve this, data from 38 exploration and development wells were utilized, and approximately 1,400 microscopic thin sections from the Gadvan formation were meticulously examined. The paramount contribution of this research lies in the establishment of a representative type section for the Khalij limestone member, characterized by a thickness of 13 meters. Detailed microscopic analysis has revealed that this member predominantly comprises wackestone carbonate, featuring microfossils, particularly foraminifera from the orbitolindae family. Based on the observed species index, it has been determined to be of Barremian age and linked to a lagoon-like depositional environment.
... Thus, the upper Aptian Partial-Range Zone in GTS 2016 is reasonable and we follow here. The H. infracretacea Partial-Range Zone is traditionally defined as the interval containing the nominate zonal species from the HO of Globigerinelloides algerianus to the LO of the Paraticinella rohri (Brovina, 2017). The biostratigraphic work from Crimea (Karpuk et al., 2018) suggests that the Hedbergella trocoidea Interval Zone may be a better choice in place of this Partial-Range Zone, as the H. trocoidea is regarded as an intermediate in the evolutionary transition from Hedbergella praetrocoidea to P. rohri (Premoli Silva et al., 2009;Huber and Leckie, 2011;Brovina, 2017;Karpuk et al., 2018). ...
... The H. infracretacea Partial-Range Zone is traditionally defined as the interval containing the nominate zonal species from the HO of Globigerinelloides algerianus to the LO of the Paraticinella rohri (Brovina, 2017). The biostratigraphic work from Crimea (Karpuk et al., 2018) suggests that the Hedbergella trocoidea Interval Zone may be a better choice in place of this Partial-Range Zone, as the H. trocoidea is regarded as an intermediate in the evolutionary transition from Hedbergella praetrocoidea to P. rohri (Premoli Silva et al., 2009;Huber and Leckie, 2011;Brovina, 2017;Karpuk et al., 2018). However, Hedbergella trocoidea is confined to the uppermost Hedbergella infracretacea Partial-Range Zone in the Chaqiela section. ...
Marine sedimentary intervals of the upper Barremian–upper Aptian record the profound changes in global plate configurations and the ocean-climate system. Black shale lithofacies of the Lower Cretaceous crop out extensively in the Tethyan Himalaya region of southern Tibet, and in the Gamba area they are assigned to the Gambadongshan Formation. By using 3–5% hydrofluoric acid, well-preserved planktic foraminiferal tests have been recovered for the first time from black shales in the Chaqiela section of the Gambadongshan Formation. The detailed foraminiferal biostratigraphic work allowed recognition of four upper Barremian to upper Aptian planktic biozones: Hedbergella excelsa Interval Zone, Globigerinelloides ferreolensis Taxon-Range Zone, Hedbergella infracretacea Partial-Range Zone, and the Paraticinella rohri Taxon-Range Zone. Total organic carbon (TOC) and organic carbon isotope (δ¹³Corg) records were generated for the Chaqiela section. The C-isotope profile and the planktic foraminiferal data enable the identification of Oceanic Anoxic Event 1a (OAE 1a) at the lower part of the Globigerinelloides ferreolensis Taxon-Range Zone. Diagenetic processes, lower sea surface temperature, and the regional hydrologic cycle were probably the main factors for the development of OAE 1a in the Chaqiela section. The relatively higher δ¹³Corg values and smaller size of carbon isotopic fluctuations in the Chaqiela section may represent the local expression of OAE 1a in the Gamba area. A long-term negative δ¹³Corg excursion and a decreased trend of planktic foraminiferal abundance relative to benthic foraminifera, in the upper part of the Gambadongshan Formation may suggest a lower sea-level during the late Aptian.
... They are composed of soft gray to pale calcareous mudstones and marls mostly lack in macrofossils, but rich in planktonic and benthic foraminifera, nannofossils, dinocysts and ostracods. The studies of microfossil assemblages from the southwest and central Crimea enabled the detailed stratigraphic division and correlation of these deposits (Gorbachik and Yanin, 1972;Gorbachik, 1986;Baraboshkin et al., 2004;Karpuk andTesakova, 2013, 2014;Matveev, 2016;Brovina, 2017;Brovina et al., 2017;Karpuk et al., 2018). However, despite a wide cropping-out of the upper Barremian-Aptian strata, the interval correlatable to OAE1a appeared to be covered by vegetation in the most parts of the area. ...
Abstract
The early Aptian Oceanic Anoxic Event 1a (OAE1a, or Selli Event) is widely known from many oceanic and inland sections as an interval of enhanced accumulation of sediments rich in total organic carbon (TOC), associated with the turnover in the global carbon budget and dramatic biotic variations. Our multidisciplinary study of the upper Barremian to lower upper Aptian deposits from the eastern part of Crimean Peninsula allowed us to confirm the presence of a layer that correlates to OAE1a and revealed significant reorganization in the planktonic and benthic foraminifera, nannofossils, ostracod and terrestrial plant communities at this level. The low-calcareous OAE1a deposits from the eastern Crimea lack in TOC that is not typical sedimentological response to this critical event. The OAE1a onset was associated with a nannoconid crisis, occurrence of low-abundance Hedbergella planktonic foraminifera, increased abundance of benthic foraminifera and ostracods and the bloom of Classopolis on the adjacent land. The calcareous microplankton biota was highly oppressed during OAE1a up to total elimination in the core of the event. Benthic assemblages indicate the occurrence of dysoxic conditions at the sea-floor. The absence of organic matter in the deposits of the OAE1a interval points to the low basinal biotic productivity and low input of terrestrial organic matter. We suggest that oligotrophication of the basin was related to the transgressive pulse, which led to small-scale landward moving of the coastal line barriered by coastal highland. The hot arid climatic conditions indicated by terrestrial plants, prevented the supply of nutrients and terrestrial organic matter into the basin that caused low algal and bacterial productivity and prevented accumulation of TOC-rich sediments. The termination of OAE1a coincides with the occurrence of warm humid climate and erosion of ephemeral coastal highland, more likely, built up by soft clayey sediments. The transit restoration of the normal marine biota in the early late Aptian was interrupted in the middle late Aptian by new long-lived regression led to enhanced terrestrial runoff and, possibly, fresh water input killed marine biota and caused the accumulation of low-calcareous clay.
... Instead of Globigerinelloides blowi, some authors have preferred to use Blowiella blowi, like Aguado et al. (1999), Rückheim and Mutterlose (2002), Mandic and Lukeneder (2008) and Brovina (2017) that identified Blowiella blowi. Krechmar and Gorbachik (1971) originally defined Blowiella which does not contain multilamellar thickening of the wall different from Globigerinelloides. ...
The Mudurnu – Nallıhan Sequence that comprises the Upper Jurassic – Lower Cretaceous carbonate succession was cut by diabase dykes and intercalated with volcano-sedimentary rocks in the Nallıhan region, Ankara, Turkey. The sequence consists of the Yosunlukbayırı Formation and the Soğukçam Limestone. This study focuses on the high-resolution biostratigraphy and microfacies analyses of the Soğukçam Limestone widely exposed in the north of the Nallıhan town. For this purpose, the stratigraphic section was measured (94.73 m thick) and a total of 44 samples were collected from limestone, shale and diabase dyke.
By using planktonic foraminiferal bioevents, the following biozones were established in ascending order: Globigerinelloides blowi Zone (Early Aptian), Leupoldina cabri Zone (Early Late Aptian) and Globigerinelloides ferreolensis Zone (Late Aptian). Eight species of Hedbergella, three species of Globigerinelloides, and Leupoldina cabri were identified in the study. Only the presence of these r-mode opportunistic planktonic foraminifera, Hedbergella and Globigerinelloides, in the studied samples indicates that eutrophic environmental conditions prevailed in the Aptian time in the studied region. The elongated chamber forms, such as Hedbergella roblesae and Leupoldina cabri, low-oxygen planktonic foraminifers suggests that the Oceanic
Anoxic Event 1a (the Selli Event) has possibly been recorded in the Leupoldina cabri Zone of the studied sequence. In addition, small benthic foraminifera, radiolaria and Cadosina sp. were recorded through the measured section.
Based on both lithofacies analysis (determination of the depositional texture), and biofacies analysis (fossil assemblages), microfacies types were defined as MF-1: Radiolarian mudstone / wackestone, MF-2: Planktonic foraminiferal and radiolarian wackestone / packestone and MF-3: Planktonic foraminiferal mudstone / wackestone. In the light of the microfacies analyses, the depositional environments of the Aptian part of the Soğukçam Limestone were determined as toe of slope to deep water basin.
Keywords: Planktonic foraminifera, Biostratigraphy, Aptian, Soğukçam Limestone, Nallıhan/Ankara
... Ostracods of these species were collected from six sections, Verkhorechie, Krasnaya Gorka, Kirpichnoe, Maryino, Kurskoe, and Zavodskaya Balka. The age of the sections was determined using ostracods, planktonic foraminifera and calcareous nannofossils (Karpuk, 2016;Brovina, 2017;Brovina et al., 2017;Karpuk et al., 2018). The new species Protocythere whatleyi Karpuk, sp. ...
... The BarremianeAptian succession in all the studied sections is built up by light gray mudstones, intercalating with reddish dense layers rich in ferrous oxides. All sections were correlated with each other using ostracods (Karpuk, 2016), and five of them (Tables A2, A4, A5, A7 and A9) were also correlated using planktic Foraminifera (Gorbachik, 1986;Brovina, 2017;Brovina et al., 2017) and calcareous Nannoplankton (Shcherbinina and Loginov, 2012;Brovina et al., 2017;Karpuk et al., 2018). ...
A method of reconstruction of outer sublittoral relative depth using ostracods has been suggested. The new method is based on an increasing percentage of ostracods with distinct eye tubercle with water depth rising. The proposed method was developed and checked on late Barremian – Aptian ostracods of the Crimea; the results are similar to those obtained from oxygen isotope analysis and principal component analyses. The combined curve of the depth changing in the Crimean sea during late Barremian – Aptian aligns with the global eustatic curve.
The Aptian sedimentary deposits of the Castro Urdiales area in north Spain record an episode of disoxia/anoxia which postdates Oceanic Anoxic Event 1a (OAE 1a). Carbonate platform and overlying facies are analysed for stratigraphy, sedimentology, total organic carbon and carbon isotopes. Lower Aptian shallow-water limestones are covered by deeper-water marlstones and organic-carbon-rich black lutites of early to late Aptian, ranging from Dufrenoyia furcata Zone to Cheloniceras (Epicheloniceras) martinioides Zone. Biostratigraphy and chemostratigraphic calibration are based on ammonites, carbon isotopes and total organic carbon analyses, revealing consistency with the global Aptian reference framework. The Castro Urdiales black-shale levels of the early to late Aptian transition together with their encasing series are correlated with other Aptian sections of the Basque-Cantabrian Basin (northern Spain) and southeastern France. The Castro Urdiales black shales are correlated with the Aparein Level of the eastern Basque-Cantabrian Basin. Prior to this oxygen deficient episode, glauconite-and-ostreid facies were also deposited under oxic conditions during the Gutiolo volcanic event of the Basque-Cantabrian Basin. This volcanism correlates in part with the Cretaceous superplume eruptions of Ontong Java, Manihiki Plateaus and the North Atlantic opening as a result of increasing seafloor spreading rates.
Upper Aptian planktonic foraminifera assemblages recorded in the post-salt section of the Santos, Campos and Espírito Santo Brazilian marginal basins are described and interpreted in terms of biostratigraphy and relative ages. The studied section represents the first marine sedimentary rocks deposited above the evaporitic sequence. Material from 26 Petrobras wells, including core, sidewalls and cuttings samples was analyzed. The upper Aptian planktonic foraminifera assemblages are composed mainly of cosmopolitan and chronostratigraphically long-ranging species, among which 22 species have been commonly recorded in the Tethyan Realm and other South Atlantic basins. Considering the biostratigraphic distribution, deposition of the studied section spans from the upper Aptian Globigerinelloides ferreolensis to Paraticinella rohri zones. Hence, the present study allowed the reassessment of the biostratigraphic framework, pointing out to an upper Aptian age for the marine section deposited immediately above the evaporitic sequence in the Santos, Campos and Espírito Santo basins. Indeed, a marine environment was established 5 to 10 Ma earlier than previously proposed. The reevaluation of the age constraints for the section provides new insight to the understanding of early South Atlantic Ocean geological evolution.
Based on examination of the type material deposited by Jacques Sigal at the Musée National d'Histoire Naturelle in Paris, we have validated the hypothesis of Randrianasolo and Anglada (1998) that the holotype and para type of Ticinella bejaouaensis Sigal 1966 belong to two different species, the distributions of which do not overlap. Indeed, the holotype is of late Albian age and from Madagascar whilst the paratype is of a latest Aptian age and from Tunisia. Sigal's paratype is here confirmed to be the holotype of the species eubejaouaensis Randrianasolo and Anglada, 1998. It displays a distinctive wall texture bearing perforation cones that coalesce to form irregularly arranged rugosities and ridges, which tend to parallel the periphery. In addition, flaps may cover the umbilical area. However, it lacks true umbilical supplementary apertures and therefore cannot be included in the genus Ticinella Reichel, 1950. The new genus Paraticinella, with Paraticinella eubejaouaensis as the type species, is here formalized to accommodate uppermost Aptian trochospiral individuals with a wall texture bearing perforation cones, rugosities, and ridges in patterns paralleling the margin, and possessing an umbilical cover-plate. Paraticinella eubejaouaensis evolved from Hedbergella trocoidea in the upper Aptian. The evolutionary trend is exemplified by the increasing number of chambers, by flattening of the spire height, by widening of the umbilicus with the appearance of a cover-plate, by acquisition of well-developed ridges on wall surfaces, and by the appearance of weakly developed infralaminal accessory apertures in later specimens of P. eubejaouaensis. A close study of the holotype of Ticinella bejaouaensis Sigal, 1966 reveals a substantial similarity in morphology and wall structure with Ticinella roberti and a lack of distinguishing criteria between the two species. Consequently, the species Ticinella bejaouaensis is invalidated and is considered to be a junior synonym of T. roberti. A third species was observed associated with Ticinella roberti and Biticinella breggiensis in Madagascar and Spain, and it is attributable to the genus Ticinella based on the presence of true umbilical supplementary apertures and a typical Ticinella wall structure (muricate to coarsely pustulose), while in gross morphology, it resembles Paraticinella eubejaouaensis. We have named this new taxon Ticinella moulladei. It differs from T. roberti by its thinner test, more numerous chambers, and wider umbilicus.
In 2009 two wells were drilled with 100% core recovery at Roquefort-La Bédoule (Bouches-du-Rhône, SE France), the historical Bedoulian stratotype. Here we present holostratigraphic results based on a detailed study of the cored sediments. Our work confirms that the La Bédoule area offers one of the best records for the period spanning the late Bedoulian, the anoxic event OAE1a and the Bedoulian/Gargasian (lower-upper Aptian substages) transition. New data provide a refined succession of micropaleontogical events already well correlated with ammonites from previous fieldwork and, thus, improve the cross-calibration of bioevents with high-resolution isotope stratigraphy. Methods of the quantitative micropalaeontology applied on benthic foraminifera such as tritaxias help testing their probable orbitally triggered cyclicity, which might be used to precise estimates of duration of events such as OAE1a, the Dufrenoya furcata ammonite Zone, the Globigerinelloides ferreolensis planktonic foraminiferal zone and the C7 isotopic stage.
Between 1988 and 1995 the author made a layer-by-layer re-examination of most of the Lower Cretaceous sections in the Kacha - Bodrak interfluve. The study, based on samples collected by the author, students and co-workers at MGU and from collections held by other institutions and individuals, formed the basis for a reexamination of the biostratigraphy and ammonite fauna of the region. A new biostratigraphical scheme is presented and described stage by stage from the Valanginian to the Albian.
The planktonic foraminiferal taxon Ticinella bejaouaensis Sigal, 1966 had long been an important zonal biomarker for the latest Aptian characterized by its large test, numerous (8–10) final-whorl chambers, and rugose test surface, usually with an umbilical cover-plate. Upon confirmation that Sigal's Madagascan holotype was actually from the upper Albian, this species was renamed as T. eubejaouaensis Randrianasolo and Anglada, 1998 using Sigal's Tunisian bejaouaensis paratype, which is late Aptian in age, as the new holotype. Following emendation of the genus, Paraticinella eubejaouaensis has recently become the standard usage. However, the validity of this species is still uncertain because the original designation was given in very obscure publication(s). Meanwhile, albeit tenuous, a presumable senior name “Paraticinella rohri (Bolli, 1959)” has recently been proposed in place of eubejaouaensis.
Rigorous assessment of the original species designation of T. eubejaouaensis ascertains that the method of publication used does not comply with the criteria required in the International Code of Zoological Nomenclature, thereby making this species an invalid name, or nomen nudum. New backscattered scanning electron microscopic observations of the primary types of Praeglobotruncana rohri Bolli, 1959 reveal that this hitherto unattended species is indeed synonymous to “T. eubejaouaensis” particularly by exhibiting equatorially aligned rugosities on the wall surface, and that the holotype is sufficiently preserved and well qualified as the name-bearing type. The latest Aptian age of the rohri type level is robustly established by its co-occurrence with Pseudoplanomalina cheniourensis (Sigal, 1952) and Hedbergella trocoidea (Gandolfi, 1942) (= another rohri paratype). Upon confirmation of the absence of any potential nomenclatural acts for conservation of the junior name “[eu]bejaouaensis,” we are obliged to provide formal redescription and establish the valid, objective senior name Paraticinella rohri (Bolli, 1959), the binomen that should be of mandatory use henceforth. Accordingly, the uppermost Aptian “[eu]bejaouaensis” Zone should be referred to as the “Pt. rohri Zone.”
Having reviewed the supraspecific taxonomy, herein the type species of the genus Paraticinella is redefined as Pt. rohri, and the subfamily Pseudoplanomalininae is proposed.
The study of planktonic foraminifera from the Lower Cretaceous succession at Angles (Southeastern France) directly correlated with ammonites, confirms that the origin of morphotypes with radially elongated chambers occur earlier than previously recorded. In particular, the species Hedbergella semielongata and Hedbergella roblesae bearing subclavate to clavate chambers first appear in the upper Hauterivian, just predating the onset of the oceanic anoxic Faraoni event. Based on these observations, a new zonation is proposed.