Ichnos最新文献

{"title":"First tetrapod swim traces and associated ichnofauna from the Mesozoic of Algeria, North Africa","authors":"Imad Bouchemla, Madani Benyoucef, Hendrik Klein, Mohammed Adaci","doi":"10.1080/10420940.2023.2258261","DOIUrl":"https://doi.org/10.1080/10420940.2023.2258261","url":null,"abstract":"AbstractWe report tetrapod traces and associated ichnofauna from two stratigraphic, dominantly terrestrial levels of the Tiout Formation (Valanginian-latest Albian to lower Cenomanian) in Laghouat and Brezina areas, Central Saharan Atlas (Djebel Amour), northwestern Algeria and discuss their paleoecological implications. The assemblages display abundant footprints that show similarities with crocodylian swim traces assigned to Hatcherichnus known from Jurassic–Cretaceous deposits of North America and Morocco. However, there is also some similarity in shape with traces attributed to swimming pterosaurs by different authors. Because of the isolated materials from Algeria and the lack of distinct trackways, we leave the decision on the tracemaker open. The majority of the traces are tridactyl to tetradactyl imprints consisting of parallel furrows left by the claws of swimming or buoyant individuals. Tetrapod swim traces are identified, described, and figured herein for the first time from the Mesozoic of Algeria. These vertebrate fossil traces are associated with a low-diversity invertebrate marine ichnofauna, including cf. Bergaueria isp., Phycodes isp., Sinusichnus cf. seilacheri, and Thalassinoides suevicus. Together with body fossil data, including abundant fishes and non-avian dinosaurs, they indicate a diverse animal community populating a fluvial system environment with marine influence. Paleoecological and paleoenvironmental features of the Tiout Formation add new information to the ichnoassemblages previously reported from the ‘mid’-Cretaceous of North Africa.Keywords: Swim tracesinvertebrate ichnofaunacontinental intercalarypaleoecologySaharan AtlasAlgeria AcknowledgementsWe are grateful to the reviewers Martin Lockley and Adrian Hunt for their valuable comments and constructive suggestions that helped improve a preliminary version of the typescript.Disclosure statementNo potential conflict of interest was reported by the authors.Additional informationFundingThis work was supported by the General Directorate of Scientific Research and Technological Development ‘DGRSDT’ (Algeria).","PeriodicalId":13037,"journal":{"name":"Ichnos","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135061253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Burrow systems of modern subterranean rodents (Ctenomyidae): key neoichnologic features and recognition of fossil examples","authors":"Maria Cristina Cardonatto, Ricardo Néstor Melchor","doi":"10.1080/10420940.2023.2258265","DOIUrl":"https://doi.org/10.1080/10420940.2023.2258265","url":null,"abstract":"AbstractThis study is aimed to identify the distinctive ichnologic features of burrow systems of two ctenomyid species of extant solitary and subterranean rodents (Ctenomys azarae and C. talarum occidentalis) from La Pampa Province (Argentina). A total of 12 active burrows from different biogeographic provinces were cast with polyurethane foam, then excavated and the entire system was mapped. Ctenomyid burrow systems are shallow (average depth 0.30 m), branched, and subhorizontal with several plugged entrances, having a main tunnel and secondary ones arranged in a single level. Curved length, tortuosity, fractal dimension branching angles, and the scarcity or absence of chambers are similar in both species. The average horizontal diameter is 66 mm, the burrow cross-section is subcircular to vertical elliptical, and entrance ramps slope at an average of 22°. Surface ornamentation in the form of sets of three curved claw traces composing a chevron pattern is dominant. Ctenomys azarae is distinguished from C. talarum occidentalis by the presence of food caches and wider sets of claw traces. Ctenomyidae burrows are easily distinguished from those of Octodontidae and Caviidae using the relative diameter index. The outlined criteria are applied to identify fossil examples of Late Miocene-Holocene ctenomyid burrows.Keywords: Semi-arid environmentrodent burrowCtenomysburrow cross-sectionsurface ornamentationclaw tracesfossil tetrapod burrow AcknowledgmentsThis research is part of the doctoral thesis in Biology by MCC at the Universidad Nacional del Comahue (San Carlos de Bariloche, Río Negro Province, Argentina). Permission to work in the Gran Salitral area was granted by the Dirección de Recursos Naturales, Government of La Pampa Province. This work was funded by project PICT2019-114 from the Agencia Nacional de Promoción Científica y Tecnológica of Argentina and project G22 from Universidad Nacional de La Pampa to RNM. We especially thank Enrique Justo and family (owners of La Florida), Hugo Cerda (owner of Puesto La Porfía), and the Cobo family (from Naicó) for allowing us to work in their land and their hospitality. Marta Kin, Fátima Mendoza Belmontes, Luciana Cobo and Nahuel Espinoza are thanked for help during fieldwork.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis work was supported by Agencia Nacional de Promoción Científica y Tecnológica [PICT2019-114] and Consejo Nacional de Investigaciones Científicas y Técnicas [PIP 2021-2023-146].","PeriodicalId":13037,"journal":{"name":"Ichnos","volume":"140 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135015584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New records of <i>Ctenopholeus</i> in the early Devonian Hunsrück Slate of Bundenbach, SW Germany","authors":"Markus J. Poschmann, Dirk Knaust, Thomas Schindler","doi":"10.1080/10420940.2023.2258264","DOIUrl":"https://doi.org/10.1080/10420940.2023.2258264","url":null,"abstract":"AbstractThe rare trace fossil Ctenopholeus kutscheri Seilacher & Hemleben, originally described from the type area of the early Devonian Hunsrück Slate at Gemünden (Germany), refers to initially open horizontal tunnels with vertically to obliquely oriented serial shafts opening to the sediment-water interface. Occurrences of frequent and partly exceptionally large specimens from Bundenbach, tentatively assigned here to C. kutscheri, reveal that these burrows, were constructed in larger numbers in the Hunsrück Slate. This happened when environmental conditions were favorable for the producer(s). Contributing factors presumably include substrate cohesion and stability being suitable for the maintenance of open burrow systems, as well as sustainable food resources during the time interval when the burrows were occupied. The new material confirms that the course of the shafts in C. kutscheri varies from almost straight to slightly bent to circular in cleavage plane view and may overlap with morphologies observed in Heliochone hunsrueckiana Seilacher & Hemleben. Holothurians and, more likely, crustaceans are discussed as possible producers of C. kutscheri from the Hunsrück Slate.Keywords: Early DevonianHunsrück SlateCtenopholeusfrequent occurrencecrustacea AcknowledgementsWe thank Wouter Südkamp (Hausen) for initially communicating the Herrenberg rock fall and Hermann Lintz (Niddatal) for providing photographs of a specimen from his collection. Ryusuke Kimitsuki and Murray Gingras (both Edmonton) kindly helped to improve Figure 1. We also thank the mayor of Bundenbach, Mrs. Verena Mächtel, for permission of access to the Herrenberg Mine and Christian Wild for guidance. We are very grateful to Sören Jensen (Badajoz), the anonymous reviewers, and the journal editors for comments that improved this contribution.Disclosure statementNo potential conflict of interest was reported by the authors.","PeriodicalId":13037,"journal":{"name":"Ichnos","volume":"214 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134910645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of X-ray computed tomography (CT) on the ichnologic interpretation of the Mira River estuary sediment core, SW Portugal","authors":"Alina Shchepetkina, Teresa Drago, Jacqueline Santos, Ana Alberto","doi":"10.1080/10420940.2023.2212120","DOIUrl":"https://doi.org/10.1080/10420940.2023.2212120","url":null,"abstract":"AbstractComputed tomography (CT) is a relatively new technique in ichnofossil analysis, which permits superior identification of individual trace fossils, their morphology, infill, tiering relationships, and preservation potential, thus providing better environmental interpretations. It also allows non-professional ichnologists to interpret trace fossils in 3D slices with ease, especially in relatively homogeneous and mud-rich sediments. Herein, CT imagery results have been compared with conventional core logging results based on two push core samples from a muddy tidal flat of the Mira River estuary, Portugal. CT images provide a significantly more accurate description of cores and their environmental interpretation due to enhanced visibility of physical and biogenic sedimentary structures. They also reveal complex tiering relationships between burrows with preferential preservation of deeper tiers. The appearance of stacked Scalichnus-like and other siphonichnidal burrows made by infaunal bivalves indicates discontinuous deposition on a tidal flat likely caused by seasonally related fluctuations in an estuarine environment.Keywords: CT scanningtieringequilibrichniapaleoenvironmental analysisestuary AcknowledgementsThis work is devoted to Dr. George S. Pemberton, who was the leading author’s Ph.D. supervisor, mentor, and “ichnological father”. Drs. Francisco Fatela and Conceição Freitas from the University of Lisbon are thanked for their valuable help in the organization of fieldwork and obtention of the push cores.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThe study was funded by the Portuguese Fundação para a Ciência e a Tecnologia (FCT) I.P./MCTES through national funds (PIDDAC) – UIDB/50019/2020 under the project “UIDP/50019/2020 – Financiamento Plurianual de Unidades de I&D 2020-2023 – IDL” and co-funded by European funds (POCI), Regional Operational Programmes (COMPETE) and national funds (FCT) under the project “European Multidisciplinary Seafloor and Water Column Observatory (Portugal) - EMSO-PT (PINFRA/22157/2016)” in the scope of “Portuguese Roadmap of Research Infrastructures”. Jacqueline Santos received financial support through grant IPMA-2020-011-BI (under the project EMSOPT) and Ana Alberto through PhD grant UIBD/151497/2021 (IDL).","PeriodicalId":13037,"journal":{"name":"Ichnos","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135641388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}