Pub Date : 2023-05-25DOI: 10.54103/2039-4942/18930
I. Ghandour, R. Bălc, M. Faris, S. Helal, G. Mosa, M. Aljahdali
The present study deals with calcareous nannoplankton paleoenvironmental and biostratigraphic implications as well as the genesis and the stratigraphic significance of an event bed recognized from the middle Eocene Beni Suef Formation in the sections of Gebel Na’alun (Fayoum area) and Gebel Homret Shaibun (Beni Suef area), Egypt. Calcareous nannoplankton biostratigraphy indicates that the Beni Suef Formation in the two areas is synchronous, covering an interval that may be correlated with the calcareous nannoplankton Zone NP17. Paleoenvironmental implications from calcareous nannoplankton suggests deposition of sediments in the Beni Suef Formation under relatively stable, temperate and mesotrophic conditions, with a short interval of eutrophication in the basal part of the Homret Shaibun section.
本文研究了埃及Gebel Na 'alun (Fayoum地区)和Gebel Homret Shaibun (Beni Suef地区)中始新世Beni Suef组事件层的古环境和生物地层学意义，以及事件层的成因和地层意义。钙质纳米浮游生物地层学表明，两地区贝尼湾组是同步的，所覆盖的层段可能与钙质纳米浮游生物带NP17有关。钙质纳米浮游生物的古环境暗示了贝尼湾组沉积物的沉积处于相对稳定、温和和中营养化的条件下，在Homret shabun剖面的底部出现了短间隔的富营养化。
{"title":"NEW INSIGHT INTO THE MIDDLE EOCENE CALCAREOUS NANNOPLANKTON BIOSTRATIGRAPHY AND PALEOENVIRONMENT FROM FAYOUM AND BENI SUEF AREAS, EGYPT","authors":"I. Ghandour, R. Bălc, M. Faris, S. Helal, G. Mosa, M. Aljahdali","doi":"10.54103/2039-4942/18930","DOIUrl":"https://doi.org/10.54103/2039-4942/18930","url":null,"abstract":"The present study deals with calcareous nannoplankton paleoenvironmental and biostratigraphic implications as well as the genesis and the stratigraphic significance of an event bed recognized from the middle Eocene Beni Suef Formation in the sections of Gebel Na’alun (Fayoum area) and Gebel Homret Shaibun (Beni Suef area), Egypt. Calcareous nannoplankton biostratigraphy indicates that the Beni Suef Formation in the two areas is synchronous, covering an interval that may be correlated with the calcareous nannoplankton Zone NP17. Paleoenvironmental implications from calcareous nannoplankton suggests deposition of sediments in the Beni Suef Formation under relatively stable, temperate and mesotrophic conditions, with a short interval of eutrophication in the basal part of the Homret Shaibun section.","PeriodicalId":54451,"journal":{"name":"Rivista Italiana Di Paleontologia E Stratigrafia","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44727189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-15DOI: 10.54103/2039-4942/19439
V. Dernov
New finds of well-preserved remains of coiled nautiloids from lower Moscovian sediments (Kamenskaya Formation) of the Donets Basin (eastern Ukraine) allowed to describe the color pattern on the conch surface of species of the genera Parametacoceras, Metacoceras, Coelogasteroceras and Ephippioceras. The conch color pattern of the studied nautiloids is represented by longitudinal light bands along the ventrolateral shoulder (Parametacoceras and Metacoceras), transverse thin lines on the venter (Ephippioceras), and a black spot on the body chamber (Coelogasteroceras). Described color patterns represent disruptive coloration. Environmental conditions, e.g. slow sedimentation, absence of agents of mechanical and chemical destruction, dysaerobic conditions and rapid burial were obviously the most important factors for the preservation of coloration on the studied conchs of coiled nautiloids.
{"title":"FIRST EVIDENCE OF COLOR PATTERNS ON CONCHS OF THE LOWER MOSCOVIAN (MIDDLE PENNSYLVANIAN) COILED NAUTILOIDS FROM THE DONETS BASIN, UKRAINE","authors":"V. Dernov","doi":"10.54103/2039-4942/19439","DOIUrl":"https://doi.org/10.54103/2039-4942/19439","url":null,"abstract":"New finds of well-preserved remains of coiled nautiloids from lower Moscovian sediments (Kamenskaya Formation) of the Donets Basin (eastern Ukraine) allowed to describe the color pattern on the conch surface of species of the genera Parametacoceras, Metacoceras, Coelogasteroceras and Ephippioceras. The conch color pattern of the studied nautiloids is represented by longitudinal light bands along the ventrolateral shoulder (Parametacoceras and Metacoceras), transverse thin lines on the venter (Ephippioceras), and a black spot on the body chamber (Coelogasteroceras). Described color patterns represent disruptive coloration. Environmental conditions, e.g. slow sedimentation, absence of agents of mechanical and chemical destruction, dysaerobic conditions and rapid burial were obviously the most important factors for the preservation of coloration on the studied conchs of coiled nautiloids.","PeriodicalId":54451,"journal":{"name":"Rivista Italiana Di Paleontologia E Stratigrafia","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46335359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-09DOI: 10.54103/2039-4942/19176
S. Renesto, F. Saller
Discovery of two different morphologies of the hindlimb in specimens ascribed to the Triassic drepanosauromorph diapsid Megalancosaurus led to the erection of two distinct species within this genus: M. preonensis and M. endennae. In the present study a re-examination of the hindlimb architecture of both Megalancosaurus species indicates that M. preonensis and M. endennae exploited different microhabitats within the arboreal environment as for many extant species belonging to the same genus, like caribbean Anoles. M. endennae, with a stronger lower leg, a larger grasping foot, an opposable clawless hallux, and deeper and more recurved claws on pedal digits 2-5 was better adapted for locomotion on narrow and intricate supports like narrow twigs on terminal branches. M.preonensis with more slender hindlimbs, absence of an opposable hallux and longer, but thinner and less recurved claws on all pedal digits may have been better adapted to live on larger supports and could also have used the long pedal claws as hooks in a sloth-like fashion. In both Megalancosaurus species the tail acted both as a prop to assume a stable tripodal gait and as a clinging device that ensured grip during bridging as in other arboreal drepanosauromorphs which skeleton is adequately known. The overall hindlimb adaptation of Megalancosaurus species are more similar to that of some small arboreal mammals rather than that of chameleons.
{"title":"DIFFERENCES IN THE HINDLIMB ANATOMY IN THE TWO SPECIES OF THE LATE TRIASSIC DREPANOSAUROMORPH DIAPSID MEGALANCOSAURUS INDICATE HABITAT PARTITIONING WITHIN THE ARBOREAL ENVIRONMENT","authors":"S. Renesto, F. Saller","doi":"10.54103/2039-4942/19176","DOIUrl":"https://doi.org/10.54103/2039-4942/19176","url":null,"abstract":"Discovery of two different morphologies of the hindlimb in specimens ascribed to the Triassic drepanosauromorph diapsid Megalancosaurus led to the erection of two distinct species within this genus: M. preonensis and M. endennae. In the present study a re-examination of the hindlimb architecture of both Megalancosaurus species indicates that M. preonensis and M. endennae exploited different microhabitats within the arboreal environment as for many extant species belonging to the same genus, like caribbean Anoles. M. endennae, with a stronger lower leg, a larger grasping foot, an opposable clawless hallux, and deeper and more recurved claws on pedal digits 2-5 was better adapted for locomotion on narrow and intricate supports like narrow twigs on terminal branches. M.preonensis with more slender hindlimbs, absence of an opposable hallux and longer, but thinner and less recurved claws on all pedal digits may have been better adapted to live on larger supports and could also have used the long pedal claws as hooks in a sloth-like fashion. In both Megalancosaurus species the tail acted both as a prop to assume a stable tripodal gait and as a clinging device that ensured grip during bridging as in other arboreal drepanosauromorphs which skeleton is adequately known. The overall hindlimb adaptation of Megalancosaurus species are more similar to that of some small arboreal mammals rather than that of chameleons.\u0000 \u0000 ","PeriodicalId":54451,"journal":{"name":"Rivista Italiana Di Paleontologia E Stratigrafia","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46405365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-03DOI: 10.54103/2039-4942/18781
J. Robledo, D. Barasoain, S. Quiñones, Enzo M. LANDA RAMIREZ, A. Zurita, C. Galli
The sedimentological characteristics and fossil vertebrates studies are notoriously increasing in the earth sciences field, as a way to infer reliable information about the biota and the paleoenvironmental and paleoclimatic context. In this framework, we establish relationships among the flora, fauna and the depositional environment during the Late Miocene in Northwestern Argentina. The sedimentology features are described in detail from sediments collected in the Quebrada Salta section, and the Xenarthra Cingulata Kraglievichia paranensis (Pampatheriidae) and Cranithlastus xibiensis (Glyptodontidae) are recorded for the first time in the Palo Pintado Formation (Salta Province, Argentina). The sedimentary observations support the presence of a sinuous sandy-gravel fluvial system with swamps and lacustrine, under a wet tropical climate. In this environment, the vertebrates here described would have inhabited open zones close to these freshwater bodies, predominated by xeric vegetation, mainly represented by grasses and sedges with scarce arboreous elements.
{"title":"RECONSTRUCTING THE LATE MIOCENE PALEOENVIRONMENT OF NORTHWESTERN ARGENTINA: NEW SEDIMENTOLOGICAL AND FAUNISTIC EVIDENCE FROM THE PALO PINTADO FORMATION","authors":"J. Robledo, D. Barasoain, S. Quiñones, Enzo M. LANDA RAMIREZ, A. Zurita, C. Galli","doi":"10.54103/2039-4942/18781","DOIUrl":"https://doi.org/10.54103/2039-4942/18781","url":null,"abstract":"The sedimentological characteristics and fossil vertebrates studies are notoriously increasing in the earth sciences field, as a way to infer reliable information about the biota and the paleoenvironmental and paleoclimatic context. In this framework, we establish relationships among the flora, fauna and the depositional environment during the Late Miocene in Northwestern Argentina. The sedimentology features are described in detail from sediments collected in the Quebrada Salta section, and the Xenarthra Cingulata Kraglievichia paranensis (Pampatheriidae) and Cranithlastus xibiensis (Glyptodontidae) are recorded for the first time in the Palo Pintado Formation (Salta Province, Argentina). The sedimentary observations support the presence of a sinuous sandy-gravel fluvial system with swamps and lacustrine, under a wet tropical climate. In this environment, the vertebrates here described would have inhabited open zones close to these freshwater bodies, predominated by xeric vegetation, mainly represented by grasses and sedges with scarce arboreous elements.","PeriodicalId":54451,"journal":{"name":"Rivista Italiana Di Paleontologia E Stratigrafia","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41917793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-27DOI: 10.54103/2039-4942/16733
L. Jaselli, Vittorio Pieroni
An echinoderm fauna from the San Salvatore Formation (Middle Triassic, Southern Alps) is here described in detail for the first time. Identifiable crinoids and echinoids were collected from three different localities: Mt. San Salvatore (Ticino, Switzerland), Rasa di Varese and San Michele (Lombardy, Italy). Crinoid taxa include Encrinus cf. aculeatus, Holocrinus sp. indet., Zardinicrinus cf. granulosus, Encrinidae gen. et sp. indet. Echinoid taxa include “Cidaris” cf. roemeri, Serpianotiaris sp. indet., Triadocidaris transversa, Triadocidaris sp. indet., and an indetermined form (Cidaridae). Most of the material was collected from Rasa di Varese, along with a rich upper Anisian ammonoid and conodont fauna, belonging to the upper Reitzi Zone and the Secedensis Zone. Migration of crinoids have been documented during the upper Anisian (from upper Pelsonian to lower Illyrian), mainly from the westernmost Tethyan Realm northward to the Germanic basin. Crinoid taxa already reported in the lower and upper Illyrian of the Germanic basin have also been collected, dated here to the late Illyrian (upper Reitzi Z.-Secedensis Z.) suggesting that several taxa migrated southwards in the Tethys realm during the late Illyrian.
{"title":"MIDDLE TRIASSIC ECHINODERMS FROM THE SAN SALVATORE FORMATION OF LOMBARDY (ITALY) AND CANTON TICINO (SWITZERLAND)","authors":"L. Jaselli, Vittorio Pieroni","doi":"10.54103/2039-4942/16733","DOIUrl":"https://doi.org/10.54103/2039-4942/16733","url":null,"abstract":"An echinoderm fauna from the San Salvatore Formation (Middle Triassic, Southern Alps) is here described in detail for the first time. Identifiable crinoids and echinoids were collected from three different localities: Mt. San Salvatore (Ticino, Switzerland), Rasa di Varese and San Michele (Lombardy, Italy). Crinoid taxa include Encrinus cf. aculeatus, Holocrinus sp. indet., Zardinicrinus cf. granulosus, Encrinidae gen. et sp. indet. Echinoid taxa include “Cidaris” cf. roemeri, Serpianotiaris sp. indet., Triadocidaris transversa, Triadocidaris sp. indet., and an indetermined form (Cidaridae). Most of the material was collected from Rasa di Varese, along with a rich upper Anisian ammonoid and conodont fauna, belonging to the upper Reitzi Zone and the Secedensis Zone. Migration of crinoids have been documented during the upper Anisian (from upper Pelsonian to lower Illyrian), mainly from the westernmost Tethyan Realm northward to the Germanic basin. Crinoid taxa already reported in the lower and upper Illyrian of the Germanic basin have also been collected, dated here to the late Illyrian (upper Reitzi Z.-Secedensis Z.) suggesting that several taxa migrated southwards in the Tethys realm during the late Illyrian.","PeriodicalId":54451,"journal":{"name":"Rivista Italiana Di Paleontologia E Stratigrafia","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49503172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-31DOI: 10.54103/2039-4942/19030
D. Ridente
Hildoceras bifrons (Bruguière, 1789) is a cosmopolite ammonite species from the Lower Jurassic of the Boreal and Mediterranean (Tethys) palaeogeographical provinces. Inter-demic and phylogenetic variability are noticeable, also affecting the most distinctive morphological trait: the spiral groove along the whorl flank. Since the XIX century, however, a number of morphotypes assigned to Hildoceras bifrons (many of which from the Apennines and other Italian localities) lacked a neat spiral groove, replaced by a shallow, variably evident and discontinuous inflection. Buckman (1918) provided a photographic illustration of a specimen he interpreted as corresponding to the holotype, until then represented by a drawing described by Lister (1678) as Ammonis cornu. Buckman’s illustration assessed the well-carved spiral groove as a distinctive feature of the holotype and a trademark of the species. Nevertheless, several authors insisted on referring faintly grooved specimens to Hildoceras bifrons, an attitude thus envisaged as due to their negligence or inaccuracy. In contrast with this view, it is herein argued that, on one hand, the specimen illustrated by Buckman, in quality of holotype or neotype, differs from Lister’s drawing to a point that it may not be the same specimen; on the other hand, Lister’s drawing (never formally invalidated as holotype) could have been legitimately considered representative also of those faintly grooved Hildoceras now assigned to Hildoceras lusitanicum Meister, 1913. This alternative view clarifies the taxonomic approach held by many authors, proving the coherency of their taxonomic work rather than their attitude at a superficial evaluation of diagnostic traits.
{"title":"MARTIN LISTER’S 1678 AMMONIS CORNU AND THE MISREADING OF HILDOCERAS BIFRONS (BRUGUIÈRE, 1789). AN HISTORICAL INSIGHT ON THE RELEVANCE OF ARTWORK AND DETAILS IN TAXONOMY","authors":"D. Ridente","doi":"10.54103/2039-4942/19030","DOIUrl":"https://doi.org/10.54103/2039-4942/19030","url":null,"abstract":"Hildoceras bifrons (Bruguière, 1789) is a cosmopolite ammonite species from the Lower Jurassic of the Boreal and Mediterranean (Tethys) palaeogeographical provinces. Inter-demic and phylogenetic variability are noticeable, also affecting the most distinctive morphological trait: the spiral groove along the whorl flank. Since the XIX century, however, a number of morphotypes assigned to Hildoceras bifrons (many of which from the Apennines and other Italian localities) lacked a neat spiral groove, replaced by a shallow, variably evident and discontinuous inflection. Buckman (1918) provided a photographic illustration of a specimen he interpreted as corresponding to the holotype, until then represented by a drawing described by Lister (1678) as Ammonis cornu. Buckman’s illustration assessed the well-carved spiral groove as a distinctive feature of the holotype and a trademark of the species. Nevertheless, several authors insisted on referring faintly grooved specimens to Hildoceras bifrons, an attitude thus envisaged as due to their negligence or inaccuracy. In contrast with this view, it is herein argued that, on one hand, the specimen illustrated by Buckman, in quality of holotype or neotype, differs from Lister’s drawing to a point that it may not be the same specimen; on the other hand, Lister’s drawing (never formally invalidated as holotype) could have been legitimately considered representative also of those faintly grooved Hildoceras now assigned to Hildoceras lusitanicum Meister, 1913. This alternative view clarifies the taxonomic approach held by many authors, proving the coherency of their taxonomic work rather than their attitude at a superficial evaluation of diagnostic traits.","PeriodicalId":54451,"journal":{"name":"Rivista Italiana Di Paleontologia E Stratigrafia","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46674589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-30DOI: 10.54103/2039-4942/18626
D. Sciunnach, F. Tremolada, I. Premoli Silva, G. Scardia
The middle Eocene Cibrone Formation of Brianza (central-western Lombardy) represents an important stratigraphic record to understand a key step of the tectonic evolution of the Alpine range poorly recorded elsewhere. Quantitative petrographic analysis of turbidite arenites, well-constrained in age by the biostratigraphy of interlayered marlstones based on calcareous foraminifera and nannoplankton, allowed us to identify a possible vertical compositional trend within the Cibrone Fm. and to document the NP17 nannofossil Zone (Bartonian) in central Lombardy exposures, east of the Ternate Formation outcrop area. Variable arenite compositions are interpreted to reflect contributions from different source areas, i.e., recycled orogen, island arc, and starved continental shelf. In a paleogeographic scenario still open to different interpretations, the proposed reconstruction supports a classical plate tectonics model for arc-trench systems. The stratigraphic gap, recorded everywhere in Lombardy, between the Eocene succession and the base of the Gonfolite Lombarda Group (upper NP24 nannofossil Zone, early Chattian), corresponds to the earliest stage of continental collision, uplift and erosion that climaxed in the Neo-Alpine Phase.
{"title":"MIDDLE EOCENE IN THE ALPINE RETROFORELAND BASIN (NORTHERN ITALY): SEDIMENTARY RECORD OF A “MESO-ALPINE” ARC-TRENCH SYSTEM IN THE ALPS","authors":"D. Sciunnach, F. Tremolada, I. Premoli Silva, G. Scardia","doi":"10.54103/2039-4942/18626","DOIUrl":"https://doi.org/10.54103/2039-4942/18626","url":null,"abstract":"The middle Eocene Cibrone Formation of Brianza (central-western Lombardy) represents an important stratigraphic record to understand a key step of the tectonic evolution of the Alpine range poorly recorded elsewhere. Quantitative petrographic analysis of turbidite arenites, well-constrained in age by the biostratigraphy of interlayered marlstones based on calcareous foraminifera and nannoplankton, allowed us to identify a possible vertical compositional trend within the Cibrone Fm. and to document the NP17 nannofossil Zone (Bartonian) in central Lombardy exposures, east of the Ternate Formation outcrop area. Variable arenite compositions are interpreted to reflect contributions from different source areas, i.e., recycled orogen, island arc, and starved continental shelf. In a paleogeographic scenario still open to different interpretations, the proposed reconstruction supports a classical plate tectonics model for arc-trench systems. The stratigraphic gap, recorded everywhere in Lombardy, between the Eocene succession and the base of the Gonfolite Lombarda Group (upper NP24 nannofossil Zone, early Chattian), corresponds to the earliest stage of continental collision, uplift and erosion that climaxed in the Neo-Alpine Phase.","PeriodicalId":54451,"journal":{"name":"Rivista Italiana Di Paleontologia E Stratigrafia","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43335867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-06DOI: 10.54103/2039-4942/18615
S. Visentin, G. Faucher, E. Erba
Calcareous nannofossil biostratigraphy was conducted in the Toarcian-lower Bajocian interval at Colle di Sogno (Lombardy Basin, Southern Alps, Northern Italy) where the type-section of the Sogno Formation consisting of pelagic marly limestone, marlstone and marly claystone was established. Semiquantitative analyses of calcareous nannofossil assemblages allowed to achieve a high-resolution biostratigraphy based on several biohorizons, including zonal/subzonal markers and additional events. The NJT5 to NJT9 Zones of the standard nannofossil zonation established for the Mediterranean Province were identified. The biostratigraphy obtained at Colle di Sogno was compared to published nannofossil events calibrated with ammonite zones in sections from SE Spain, S France, Portugal and N Algeria. This assessment evidenced some discrepancies in the succession of events of the standard zonation and, furthermore, resulted in the revision of the age of a few datums. Moreover, some new/additional nannofossil biohorizons are proposed as subzonal markers. A morphometric analysis of the genus Watznaueria was conducted to identify diagnostic features for unambiguous species identification. The species W. colacicchii and W. contracta are distinguished on the basis of the coccolith width/central area width ratio, whereas W. britannica britannica is discriminated by the size - as in the original definition of the species - relative to the new subspecies W. britannica minor. The new species W. gaetanii differs from all other Watznaueria taxa by the bridge ultrastructure. In the Toarcian-Aalenian interval a progressive increase in size of Watznaueria specimens is paralleled by the progressive closure of the central area and the modification of the central area structure passing from a cross (W. colacicchii and W. contracta) to a double-button bridge (W. gaetanii) to a single-button bridge (W. britannica). These intrageneric evolutionary innovations accelerated in the Aalenian under stable paleoceanographic conditions and an oligotrophic regime.
在意大利北部伦巴第盆地Colle di Sogno的toarcian - Bajocian下段进行了钙质纳米化石生物地层学研究，建立了Sogno组由海相泥灰岩、泥灰岩和泥灰岩组成的类型剖面。对钙质纳米化石组合的半定量分析可以实现基于几个生物层的高分辨率生物地层学，包括地带性/次地带性标记物和其他事件。确定了地中海省标准纳米化石分带的NJT5 ~ NJT9带。在Colle di Sogno获得的生物地层学与已发表的纳米化石事件进行了比较，这些事件与西班牙东南部、法国南部、葡萄牙和阿尔及利亚北部剖面的鹦鹉螺带进行了校准。这一评估证明了标准分区事件的先后顺序存在一些差异，此外，还对一些基准的年龄进行了修订。此外，还提出了一些新的/额外的纳米化石生物层作为亚地带性标志。对水蛭属进行了形态计量学分析，以确定诊断特征，明确物种鉴定。物种colacicchii和W. contracta是根据球核宽度/中心区宽度比值来区分的，而W. britannica britannica则是根据其相对于新亚种W. britannica minor的大小来区分的。该新种的桥状超微结构不同于其他所有水蛭属植物。在Toarcian-Aalenian区间，Watznaueria标本大小的逐渐增加与中心区域的逐渐闭合和中心区域结构的改变相平行，从十字(W. colacicchii和W. contracta)到双扣桥(W. gaetanii)到单扣桥(W. britannica)。在稳定的古海洋学条件和少营养状态下，这些属内进化创新在阿勒期加速。
{"title":"CALCAREOUS NANNOFOSSIL TAXONOMY AND BIOSTRATIGRAPHY OF THE TOARCIAN-LOWER BAJOCIAN COLLE DI SOGNO SECTION (LOMBARDY BASIN, SOUTHERN ALPS, ITALY)","authors":"S. Visentin, G. Faucher, E. Erba","doi":"10.54103/2039-4942/18615","DOIUrl":"https://doi.org/10.54103/2039-4942/18615","url":null,"abstract":"Calcareous nannofossil biostratigraphy was conducted in the Toarcian-lower Bajocian interval at Colle di Sogno (Lombardy Basin, Southern Alps, Northern Italy) where the type-section of the Sogno Formation consisting of pelagic marly limestone, marlstone and marly claystone was established. Semiquantitative analyses of calcareous nannofossil assemblages allowed to achieve a high-resolution biostratigraphy based on several biohorizons, including zonal/subzonal markers and additional events. The NJT5 to NJT9 Zones of the standard nannofossil zonation established for the Mediterranean Province were identified. The biostratigraphy obtained at Colle di Sogno was compared to published nannofossil events calibrated with ammonite zones in sections from SE Spain, S France, Portugal and N Algeria. This assessment evidenced some discrepancies in the succession of events of the standard zonation and, furthermore, resulted in the revision of the age of a few datums. Moreover, some new/additional nannofossil biohorizons are proposed as subzonal markers.\u0000A morphometric analysis of the genus Watznaueria was conducted to identify diagnostic features for unambiguous species identification. The species W. colacicchii and W. contracta are distinguished on the basis of the coccolith width/central area width ratio, whereas W. britannica britannica is discriminated by the size - as in the original definition of the species - relative to the new subspecies W. britannica minor. The new species W. gaetanii differs from all other Watznaueria taxa by the bridge ultrastructure. In the Toarcian-Aalenian interval a progressive increase in size of Watznaueria specimens is paralleled by the progressive closure of the central area and the modification of the central area structure passing from a cross (W. colacicchii and W. contracta) to a double-button bridge (W. gaetanii) to a single-button bridge (W. britannica). These intrageneric evolutionary innovations accelerated in the Aalenian under stable paleoceanographic conditions and an oligotrophic regime.","PeriodicalId":54451,"journal":{"name":"Rivista Italiana Di Paleontologia E Stratigrafia","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47916548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-24DOI: 10.54103/2039-4942/18275
C. Haug, Ricardo Pérez‐de la Fuente, V. Baranov, G. T. Haug, C. Kiesmüller, Ana Zippel, M. Hörnig, J. Haug
During ontogenetic development, insects can undergo quite drastic changes (metamorphosis) until the adult stage is reached. A substantial part of this development in one group of Insecta, Holometabola, takes place during the pupa stage. Despite the pupa being recognised as an important phase, rather few depictions of pupae exist in the literature. We report here the first find of a fossil pupa of the lacewing group Mantispidae. The specimen represents an exuvia and is enclosed in Ukrainian Rovno amber, Eocene in age (c. 35–40 million years). We review the entire record of extant pupae of Mantispidae depicted in the literature or in online image repositories. With the aid of elliptic Fourier analysis, we compare the outline of the femur of the foreleg (raptorial appendage in the adults) of pupae and adults of Mantispidae. The pupae are all very similar concerning the femur, while the adults show a larger morphological diversity, particularly the extinct forms. Furthermore, our results indicate that the forelegs do not become increasingly complex throughout ontogenetic stages, but instead undergo an indirect development. According to the low variation in morphology seen in the pupa stage in Mantispidae, it is plausible that it represents a phylotypic stage for the group, i.e. a phase characterised by a significantly lower variability than other stages.
{"title":"THE FIRST FOSSIL RECORD OF A MANTIS LACEWING PUPA, AND A REVIEW OF PUPAE IN MANTISPIDAE AND THEIR EVOLUTIONARY SIGNIFICANCE","authors":"C. Haug, Ricardo Pérez‐de la Fuente, V. Baranov, G. T. Haug, C. Kiesmüller, Ana Zippel, M. Hörnig, J. Haug","doi":"10.54103/2039-4942/18275","DOIUrl":"https://doi.org/10.54103/2039-4942/18275","url":null,"abstract":"During ontogenetic development, insects can undergo quite drastic changes (metamorphosis) until the adult stage is reached. A substantial part of this development in one group of Insecta, Holometabola, takes place during the pupa stage. Despite the pupa being recognised as an important phase, rather few depictions of pupae exist in the literature. We report here the first find of a fossil pupa of the lacewing group Mantispidae. The specimen represents an exuvia and is enclosed in Ukrainian Rovno amber, Eocene in age (c. 35–40 million years). We review the entire record of extant pupae of Mantispidae depicted in the literature or in online image repositories. With the aid of elliptic Fourier analysis, we compare the outline of the femur of the foreleg (raptorial appendage in the adults) of pupae and adults of Mantispidae. The pupae are all very similar concerning the femur, while the adults show a larger morphological diversity, particularly the extinct forms. Furthermore, our results indicate that the forelegs do not become increasingly complex throughout ontogenetic stages, but instead undergo an indirect development. According to the low variation in morphology seen in the pupa stage in Mantispidae, it is plausible that it represents a phylotypic stage for the group, i.e. a phase characterised by a significantly lower variability than other stages.","PeriodicalId":54451,"journal":{"name":"Rivista Italiana Di Paleontologia E Stratigrafia","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41654227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-21DOI: 10.54103/2039-4942/18877
A. Bratishko, W. Schwarzhans, Y. Vernyhorova
Reconstructing fossil bony fish faunas using otoliths is a well-established method that allows a diverse and dense record in time and space to be assembled. Here we report about a rich otolith-based fish fauna from the middle Sarmatian s.l. (middle Bessarabian) from Jurkine, Kerch Peninsula, Crimea. The study is based on more than 5,000 specimens constituting 36 different species, 24 of which are new and 2 remain in open nomenclature. This assemblage represents the first major otolith association described from the Bessarabian. It also represents a fish fauna from the last continuous restricted marine environment that evolved in the Eastern Paratethys, was recruited from the Badenian/Tarkhanian fauna, and was not affected by the subsequent Khersonian crisis. The association of otoliths is characterized by a high content of endemic fishes that derived from the relatively well-known early Sarmatian s.l. (Volhynian) fish fauna, and it contains certain faunal elements that were trapped in the then-secluded Eastern Paratethys and did not range into younger strata. This forced endemic evolution explains the unusually high percentage of new taxa. The fish fauna is dominated by stenohaline marine shelf fishes apparently recruited from the Konkian and earlier Sarmatian s.l. (Volhynian) fauna after the Karaganian crisis. The families Gobiidae and Gadidae benefited most in this restricted marine environment, while deep-water fishes disappeared with the Karaganian crisis. In this study, we discuss the further evolution of Eastern Paratethyan fishes as far as can be reconstructed from the relatively limited data from post-Bessarabian strata, and we also outline targets for future research in the field. The stratigraphic sequence of the Jurkine section is being revised based on a detailed suite of benthic foraminifera. Implications for the stratigraphy of the middle and upper Sarmatian s.l., their boundary, and the paleoenvironments of this part of the Kerch Peninsula are discussed.
{"title":"THE ENDEMIC MARINE FISH FAUNA FROM THE EASTERN PARATETHYS RECONSTRUCTED FROM OTOLITHS FROM THE MIOCENE (MIDDLE SARMATIAN S.L.; BESSARABIAN) OF JURKINE (KERCH PENINSULA, CRIMEA)","authors":"A. Bratishko, W. Schwarzhans, Y. Vernyhorova","doi":"10.54103/2039-4942/18877","DOIUrl":"https://doi.org/10.54103/2039-4942/18877","url":null,"abstract":"Reconstructing fossil bony fish faunas using otoliths is a well-established method that allows a diverse and dense record in time and space to be assembled. Here we report about a rich otolith-based fish fauna from the middle Sarmatian s.l. (middle Bessarabian) from Jurkine, Kerch Peninsula, Crimea. The study is based on more than 5,000 specimens constituting 36 different species, 24 of which are new and 2 remain in open nomenclature. This assemblage represents the first major otolith association described from the Bessarabian. It also represents a fish fauna from the last continuous restricted marine environment that evolved in the Eastern Paratethys, was recruited from the Badenian/Tarkhanian fauna, and was not affected by the subsequent Khersonian crisis. The association of otoliths is characterized by a high content of endemic fishes that derived from the relatively well-known early Sarmatian s.l. (Volhynian) fish fauna, and it contains certain faunal elements that were trapped in the then-secluded Eastern Paratethys and did not range into younger strata. This forced endemic evolution explains the unusually high percentage of new taxa. \u0000 The fish fauna is dominated by stenohaline marine shelf fishes apparently recruited from the Konkian and earlier Sarmatian s.l. (Volhynian) fauna after the Karaganian crisis. The families Gobiidae and Gadidae benefited most in this restricted marine environment, while deep-water fishes disappeared with the Karaganian crisis. In this study, we discuss the further evolution of Eastern Paratethyan fishes as far as can be reconstructed from the relatively limited data from post-Bessarabian strata, and we also outline targets for future research in the field. \u0000The stratigraphic sequence of the Jurkine section is being revised based on a detailed suite of benthic foraminifera. Implications for the stratigraphy of the middle and upper Sarmatian s.l., their boundary, and the paleoenvironments of this part of the Kerch Peninsula are discussed.","PeriodicalId":54451,"journal":{"name":"Rivista Italiana Di Paleontologia E Stratigrafia","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43987463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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