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DOAJ Open Access 2026
A morphometric approach to the taxonomic dilemma of Zonozoe drabowiensis Barrande, 1872 and Zonoscutum solum Chlupáč, 1999 (Upper Ordovician, Czech Republic)

Lorenzo Lustri, Lukáš Laibl, Luis Collantes et al.

Zonozoe drabowiensis Barrande, 1872 and Zonoscutum solum Chlupáč, 1999 are rare and incompletely preserved arthropods from the Upper Ordovician of the Czech Republic. Their classification has been a subject of debate for over a century due to the limited number of specimens, lack of knowledge related to post-cephalic morphology and the absence of clear diagnostic features. They were previously considered as members of Aglaspidida, an extinct group of arthropods from the Cambrian and Ordovician, within Vicissicaudata, a branch of the larger arthropod clade Artiopoda. Herein, we analysed the cephalic outlines of Zonozoe and Zonoscutum to determine whether their shapes align more closely with vissicaudatans than with other early Palaeozoic arthropods, offering a new morphological perspective on their systematics. We assembled a data set of cephalic outlines each representing one of thirty-three early Palaeozoic species, including Zonozoe, Zonoscutum, nine euchelicerates, six aglaspidids, three cheloniellids, and a selection of other artiopodans. We quantified their shape using elliptical Fourier analysis. Principal component analysis (PCA) and linear discriminant analysis (LDA) place Zonozoe within the vicissicaudatan morphospace, and Zonoscutum in their proximity, clearly distinguishing them from euchelicerates. These data add support to the most conservative classification of Zonozoe and Zonoscutum within Artiopoda, while strengthening the case for a more specific affinity with Vicissicaudata, helping to resolve a 150-year-old taxonomic uncertainty. More broadly, this study demonstrates the value of outline-based morphometrics in aiding systematic hypotheses when discrete characters are unavailable or scarce, offering a reproducible tool for re-evaluating other problematic fossils.

Fossil man. Human paleontology, Paleontology
DOAJ Open Access 2025
An almost complete cranium of Asoriculus gibberodon (Petényi, 1864) (Mammalia, Soricidae) from the early Pliocene of the Jradzor site, Armenia

Hugo Bert, Loic Costeur, Sergei Lazarev et al.

Abstract We describe an almost complete fossil cranium of a shrew, identified as Asoriculus gibberodon (Petényi, 1864) from the early Pliocene of Jradzor site, Armenia. The sedimentary unit, which yielded the specimen, is an 11-m-thick package composed of white thinly-parallel-laminated diatomite laying at the base of the Jradzor section. It was dated at 4.29 ± 0.09 Ma based on the magnetostratigraphy and 40Ar/39Ar radioisotopic dating of a tephra layer located at the top of the diatomite package. The skull from Jradzor shows several synapomorphies that allow its assignment to the Soricinae subfamily and Neomyini tribe. Among Neomyini, as far as the cranium anatomy is known, the specimen from Jradzor is most similar to that of Soriculus and Episoriculus. Both petrosal bones are preserved and are studied thanks to a 3D modelling of their morphology based on a CT-scan. Compared with other eulipotyphlans, the bony labyrinth of A. gibberodon from Jradzor shows a morphology typical of soricids. Its anatomy also indicates a high-frequency auditory capability similar to that of modern shrews but cannot confirm an echolocation system neither does it shows any feature that can be related to a specific locomotory adaption or ecological characteristic. The discovery of this cranium inside diatomites, corresponding to a distal lacustrine environment, raises the question of the possible semi-aquatic adaptation of this species (this adaptation being known for other extant species of the family). However, Soriculus and Episoriculus, the two genera closest to Asoriculus based on cranial anatomy are not semi-aquatic and are clearly distinguished from semi-aquatic Neomys shrews. The inner ear morphology is more similar to that of terrestrial shrews despite the general similarities among soricids and suggests an echolocation-based orientation using high frequencies to navigate through low vegetation, which is often essential in high metabolic rate organisms to reduce energy expenditure. We therefore propose a terrestrial locomotion for A. gibberodon, consistent with its previously proposed paleoecological model, depicting it was a terrestrial species inhabiting wet or humid environments in close proximity to permanent bodies of water.

Fossil man. Human paleontology, Paleontology
DOAJ Open Access 2025
The paleoecology and taphonomy of a Santonian-Campanian (Upper Cretaceous) dinosaur-bearing vertebrate locality from Bulgaria: a window into an underexplored part of the Late Cretaceous European Archipelago

Vladimir Nikolov, Polina Pavlishina, Docho Dochev et al.

Abstract The Upper Cretaceous European vertebrate fossil record has improved significantly in the past three decades but there still remain chronostratigraphic and geographic gaps, which obscure our understanding of the paleobiogeography and evolution within the insular environments of the Late Cretaceous European Archipelago. Recently, a new vertebrate locality of late Santonian–early Campanian age was discovered in westernmost Bulgaria, promising to fill some of these gaps. Here, we use a multidisciplinary approach involving palynology, paleontology and paleohistology to investigate aspects of the paleoecology and taphonomy of this new locality and to provide preliminary information on its taxonomic contents. Palynomorph data shows that the flora was dominated by angiosperms of the Normapolles group with subordinate presence of ferns and only rare gymnosperms. The association of the pollen taxa Krutzschipollis crassus and K. spatiosus supports latest Santonian to early Campanian age for the vertebrate-bearing strata. The floral composition and especially a number of fern spore humidity indicators imply the existence of a generally humid subtropical climate, with some seasonal droughts. Using palynofacies analysis, we infer a coastal, proximal shelf to oxidated deltaic or lagoonal depositional environment for the examined sedimentary succession. The locality has so far yielded 250 vertebrate specimens collected from eight strata. There are at least seven clades present, including lamniform sharks, lepisosteid gars, amphibians, turtles, crocodylomorphs, ornithopod and titanosaur dinosaurs, and possibly pterosaurs. Semi-aquatic and aquatic animals dominate the assemblage. Most common are turtles (about 30% of the sample), followed by dinosaurs. Skeletal elements are disarticulated, isolated and mostly fragmentary. Fossils are not sorted by size. Many of the fossil bones show signs of abrasion and bioerosion, both micro- and macroscopically. Paleohistological data reveal that all sampled dinosaur bones belong to subadult or adult individuals. We interpret the site to be an attritional assemblage. Taxonomic comparisons with other well-known Santonian to Maastrichtian fossil assemblages from Central (Hungary and Austria) and Eastern Europe (Romania and Serbia) indicate similarities with both the Santonian Iharkút-Ajka vertebrate fauna of Hungary and the younger Haţeg Island fauna of Romania, although additional material and more precise taxonomic identification of the Bulgarian fossils is needed. Our work presents the first more in-depth look at life on land in this currently underexplored part of the Late Cretaceous European Archipelago.

Fossil man. Human paleontology, Paleontology
S2 Open Access 2022
Paleoproteomics

Christina G Warinner, Kristine Korzow Richter, M. Collins

Paleoproteomics, the study of ancient proteins, is a rapidly growing field at the intersection of molecular biology, paleontology, archaeology, paleoecology, and history. Paleoproteomics research leverages the longevity and diversity of proteins to explore fundamental questions about the past. While its origins predate the characterization of DNA, it was only with the advent of soft ionization mass spectrometry that the study of ancient proteins became truly feasible. Technological gains over the past 20 years have allowed increasing opportunities to better understand preservation, degradation, and recovery of the rich bioarchive of ancient proteins found in the archaeological and paleontological records. Growing from a handful of studies in the 1990s on individual highly abundant ancient proteins, paleoproteomics today is an expanding field with diverse applications ranging from the taxonomic identification of highly fragmented bones and shells and the phylogenetic resolution of extinct species to the exploration of past cuisines from dental calculus and pottery food crusts and the characterization of past diseases. More broadly, these studies have opened new doors in understanding past human–animal interactions, the reconstruction of past environments and environmental changes, the expansion of the hominin fossil record through large scale screening of nondiagnostic bone fragments, and the phylogenetic resolution of the vertebrate fossil record. Even with these advances, much of the ancient proteomic record still remains unexplored. Here we provide an overview of the history of the field, a summary of the major methods and applications currently in use, and a critical evaluation of current challenges. We conclude by looking to the future, for which innovative solutions and emerging technology will play an important role in enabling us to access the still unexplored “dark” proteome, allowing for a fuller understanding of the role ancient proteins can play in the interpretation of the past.

98 sitasi en Medicine
DOAJ Open Access 2024
A revised name and new insights into the Middle Jurassic sauropod trackways from Portugal. A correction of Santos et al. 2009

Vanda F. Santos, José J. Moratalla, Rafael Royo-Torres et al.

The Galinha dinosaur tracksite (Portugal) was declared a Natural Monument in 1996 and is currently designated as Ourém/Torres Novas Dinosaur Footprints Natural Monument. This tracksite yields a completely new and unique morphology of sauropod tracks from the Middle Jurassic (Bajocian–Bathonian). This new morphotype was named Polyonyx by Santos et al. (2009). However, recently it has been brought to our attention that this ichnotaxon name “Polyonyx” is preoccupied by the porcellanid decapod Polyonyx Stimpson, 1858 (Crustacea: Decapoda: Anomura: Porcellanidae). The priority is given to the latter and to avoid homonymy, the former is issued the new replacement name Galinhapodus igen. nov., creating the new replacement combination name Galinhapodus gomesi.

Fossil man. Human paleontology, Paleontology
DOAJ Open Access 2024
Postcranial anatomy of Besanosaurus leptorhynchus (Reptilia: Ichthyosauria) from the Middle Triassic Besano Formation of Monte San Giorgio (Italy/Switzerland), with implications for reconstructing the swimming styles of Triassic ichthyosaurs

Gabriele Bindellini, Andrzej S. Wolniewicz, Feiko Miedema et al.

Abstract Besanosaurus leptorhynchus Dal Sasso & Pinna, 1996 was originally described on the basis of a single complete fossil specimen excavated near Besano (Italy). However, a recent taxonomic revision and re-examination of the cranial osteology allowed for the assignment of five additional specimens to the taxon. Here, we analyse, describe and discuss the postcranial anatomy of Besanosaurus leptorhynchus in detail. The size of the specimens examined herein ranged from slightly more than one meter to eight meters. Overall, several diagnostic character states for this taxon are proposed, demonstrating a mosaic of plesiomorphic and derived features. This is best exemplified by the limbs, which show very rounded elements in the forelimbs, and pedal phalanges with retained rudimentary shafts. We suggest that the widely spaced phalanges in the forefins of Besanosaurus leptorhynchus were embedded in a fibrocartilage-rich connective tissue, like in modern cetaceans. We also review the similarities of Besanosaurus with Pessopteryx and Pessosaurus, allowing us to conclude that Besanosaurus is not a junior synonym of either of the two taxa. Lastly, to test the swimming capabilities of Besanosaurus leptorhynchus, we expanded on a previously published study focussing on reconstructing the swimming styles of ichthyosaurs. Besanosaurus leptorhynchus was found to possess a peculiar locomotory mode, somewhat intermediate between anguilliform swimmers, such as Cymbospondylus and Utatsusaurus, and some shastasaur-grade (e.g., Guizhouichthyosaurus) and early-diverging euichthyosaurian (e.g., Californosaurus) ichthyosaurs. Based on our results, we furthermore suggest that mixosaurids acquired their characteristic body profile (dorsal fin and forefins that are distinctly enlarged compared to the hindfins) independently and convergently to the one that later appeared in Parvipelvia. Moreover, the different swimming styles inferred for Cymbospondylus, Mixosauridae, and Besanosaurus strengthen the earlier hypothesis of niche partitioning among these three distinct ichthyosaur taxa from the Besano Formation.

Fossil man. Human paleontology, Paleontology
S2 Open Access 2023
Conservation biology and conservation paleobiology meet the Anthropocene together: history matters

Sally E. Walker

As a species, we have reached a tipping point for Earth derived from our unsustainable resource use. While conservation efforts occurred early in human civilization, it was not until 1980 that the full force of environmental destruction, including the Santa Barbara oil spill in the 1970s, culminated in the new discipline of conservation biology focused on the biosphere. Similarly, conservation paleobiology, named two decades later, brings the unique perspective of the fossil record to conservation efforts, uniting biosphere and geosphere scientists. To date, conservation history does not include paleontological or geological perspectives. Further, each discipline has a different benchmark—near time—for when Earth’s ecosystems were modified by humans. Accordingly, the history of conservation efforts leading up to conservation biology and conservation paleobiology was examined from a geological and ecological framework. To provide a benchmark for near time, the hominin record and their geo-environmental modifications were also examined and revealed that by the start of the Holocene, all continents except ice-covered Antarctica and Greenland had human-modified ecosystems. Therefore, near time is dispensable when the Holocene Epoch is universally understood and precisely defined as a time when H. sapiens dominated environments. Lastly, a conservation corps is urgently needed, following the long tradition of F.D. R.’s Civilian Conservation Corps of the 1930s and J.F. Kennedy’s Peace Corps of the 1960s, to promote a global network connecting all students and practitioners of conservation disciplines to focus on biotic resilience, recovery, and solutions for the world’s most pressing environmental problems.

3 sitasi en
S2 Open Access 2023
Simulating our ability to accurately detect abrupt changes in assemblage-based paleoenvironmental proxies

C. Belanger, David W. Bapst

Resolving abrupt environmental changes in sedimentary records is critical to understanding environmental perturbations relevant on human timescales. The paleontological assemblage mixer (paleoAM) framework developed here simulates sedimentary records to measure the preservation potential of abrupt changes in assemblage-based faunal proxies while varying environmental background conditions, excursion magnitudes and durations, bioturbation, sedimentation rates, and sampling completeness. Using a record of fossil benthic foraminifera, we apply paleoAM to quantitatively determine how distinct from background conditions and how enduring an assemblage change must be to be accurately detected. At the high sedimentation rates of the case study, century-long low-oxygen events frequently have a high probability of being sampled and accurately detected, quantitatively estimated with simulations across varying sedimentation rates

2 sitasi en
DOAJ Open Access 2023
The reinstated identity of agglutinated foraminifer Campanellula capuensis from the Lower Cretaceous of southern Italy by means of a 3D model investigation

FELIX SCHLAGINTWEIT, SABRINA AMODIO, FILIPPO BARATTOLO et al.

Campanellula capuensis was described as belonging to the Trochamminacea (trochospiral tests) and later transferred to the genus Orbitolinopsis of the Orbitolinidae (uniserial tests). Challenging its identity as a species of Orbitolinopsis, the most widely accepted classifications of agglutinated foraminifera reinstate Campanellula but retain its inclusion within the Orbitolinidae, subfamily Dictyoconinae. New material from the type locality and the San Lorenzello section (Matese Mountains, southern Apennines, Italy) as well as the construction of a 3D model allow to reinstate the original description as a low- to high-trochospirally (conical) coiled foraminifer with numerous chambers per whorl and to display an overall conical test morphology. An orbitolinid test construction including uniserial chambers (throughout the test or in its adult part) is absent. The conflicting opinions on taxonomic status of Campanellula are discussed leading to the removal from the order Loftusiina and the suborder Orbitolinina. Instead, Campanellula should be included into the order Lituolida and the suborder Verneuilinina. Campanellula capuensis represents a biostratigraphic and palaeobiogeographic marker taxon, restricted to upper Hauterivian–lower Barremian inner platform carbonates of the southern Neotethyan margin.

Fossil man. Human paleontology, Paleontology
DOAJ Open Access 2023
Coral fauna across the Cretaceous–Paleogene boundary at Zagros and Sistan Suture zones and Yazd Block of Iran

Rosemarie C. Baron-Szabo, Felix Schlagintweit, Koorosh Rashidi

Abstract From the upper Maastrichtian (Tarbur Fm.) and Paleocene of Iran, 20 species of scleractinian corals belonging to 17 genera and 14 families, and one species of the octocoral Heliopora are newly recorded. Furthermore, coral species previously described from the upper Maastrichtian Tarbur Fm. and the Paleocene are revised and included in the evaluation, resulting in a total of 37 species from 28 genera belonging to 20 families (including 3 subfamilies) for the Iranian K/Pg-boundary time period. The majority of the taxa (21 out of 37 = 57%) crossed the K/Pg-boundary. The genera Acropora and Stylocoeniella are recorded from strata older than the Paleogene (upper Maastrichtian) for the first time; for Lobopsammia it is the first report from strata older than the Eocene (Selandian‒Thanetian). The vast majority of the coral taxa occurring in both the upper Maastrichtian (Tarbur Fm.) and the Paleocene of Iran have been reported from a variety of both reefal and non-reefal paleoenvironments. On the species level, a slight majority of the corals from the upper Maastrichtian (Tarbur Fm.) are endemic (14 out of 27 species = 52%). In contrast, the vast majority of the Paleocene Iranian corals are cosmopolitan to subcosmopolitan; only 4 taxa are endemic during the Paleocene. While the upper Maastrichtian coral fauna of Iran shows greatest affinities to contemporaneous assemblages of Europe and the Caribbean, the Paleocene coral fauna is most closely related to contemporaneous coral associations of central Asia, Europe, and North America.

Fossil man. Human paleontology, Paleontology
DOAJ Open Access 2023
Muscle attachment scars in helcionelloids from Denmark cast light on mollusc evolution in the Cambrian

JOHN S. PEEL, VIVIANNE BERG-MADSEN

Multiple, small (diameter <20 μm) swellings on the apex of internal moulds of the laterally compressed helcionelloids Eotebenna viviannae and the new species Eotebenna danica from the middle Cambrian (Miaolingian) of Bornholm, Denmark, are interpreted as a muscle attachment scars. The scar pattern is unique amongst currently known helcionelloids both in the abundance of attachment sites and in crossing the median plane of symmetry on the supra-apical (dorsal) surface. Sites of typically two pairs of dorsal muscle scars in other helcionelloids are distributed symmetrically on the dorso-lateral areas. The recognition of four groups of muscle scar patterns in helcionelloids suggests a degree of anatomical diversity within the group that is obscured by the morphological simplicity of the enclosing cap-shaped shells, although evolutionary links to mollusc crown groups are unresolved. In addition to the muscle scars, traces of shell micro‑structure are described.

Fossil man. Human paleontology, Paleontology
DOAJ Open Access 2023
Convergent evolution and convergent loss in the grasping structures of immature earwigs and aphidlion-like larvae as demonstrated by about 100-million-year-old fossils

Carolin Haug, Gideon T. Haug, Christine Kiesmüller et al.

Abstract Convergent evolution is a common phenomenon, independently leading to similar morphologies in different evolutionary lineages. Often similar functional demands drive convergent evolution. One example is the independent evolution of grasping structures in different lineages of Euarthropoda, though the exact morphology of these grasping structures varies significantly. In this study, we investigated grasping apparatuses with two movable counteracting structures as well as some related structures, exemplified by the stylets (compound structures of mouthparts) of aphidlion-like larvae (part of Neuroptera or lacewings) and the cerci of immature earwigs (Dermaptera). For the stylets of aphidlion-like larvae, studies have pointed to a significant loss in morphological diversity in the last 100 million years. We used quantitative morphology to evaluate if a similar process has also occurred in the cerci of earwigs. The cerci of extant immature earwigs exhibit two distinct types of morphologies in the modern fauna: elongated cerci divided into several ringlets with a feeler-type function, and pincer-like stout cerci. In some fossil immature earwigs, however, the cerci are generally elongated but undivided and roughly occupy the morphospace between those of the two modern cerci types; hence this fossil cerci morphology appears to have been lost. To some extent, a comparable loss is also found in certain lacewing larvae. Outgroup comparisons suggest that the morphologies no longer present today are in fact not ancestral, but instead specialised, hence their loss is possibly resulting from disruptive evolution in earwigs as well as lacewings. We discuss the possible functions of these specialised grasping structures.

Fossil man. Human paleontology, Paleontology
DOAJ Open Access 2022
TURTLES FROM THE MATA AMARILLA FORMATION (CENOMANIAN), SANTA CRUZ, ARGENTINA: THE SOUTHERMOST RECORD OF PROCHELIDELLA SPP. (PLEURODIRA: CHELIDAE)

Juliana Sterli, Marcelo Saúl de la Fuente, Ignacio Jorge Maniel et al.

The fossil record of Cretaceous turtles in Santa Cruz Province is scarce. Turtles have been reported from the Mata Amarilla Formation (Cenomanian), the Cerro Fortaleza Formation (Campanian–Maastrichtian), and the Chorrillo Formation (early Maastrichtian). In this contribution, we examined all the turtle remains recovered from six localities in the Mata Amarilla Formation, nearby Mata Amarilla farm (Santa Cruz Province, Argentina). These fossils are housed at the “Padre Molina” Museum in Río Gallegos, Santa Cruz. Most of the carapace and plastral remains are conferred to an indeterminate small species of cf. Prochelidella sp., while the remaining fragments are attributed to a mid-sized species of an indeterminate Chelidae. Prochelidella spp. is a group of turtles distributed in Chubut, Río Negro, Neuquén, and Mendoza provinces, ranging from the Aptian to the Maastrichtian, with two main gaps (late Albian and Coniacian–Santonian). The recognition of cf. Prochelidella sp. in the Austral-Magallanes Basin extends the geographic range of this group more than 500 km south to the previously known southernmost record of Prochelidella, Pr. argentinae, from the Golfo San Jorge Basin (Chubut, Argentina).

Fossil man. Human paleontology, Paleontology
CrossRef Open Access 2021
Fossil data do not support a long pre-Cretaceous history of flowering plants

Graham E. Budd, Richard P. Mann, James A. Doyle et al.

Abstract The origin of angiosperms is a classic macroevolutionary problem, because of their rapid rise in the Early Cretaceous fossil record, beginning about 139 Ma ago, and the conflict this creates with older crown-group ages based on molecular clock dating 1 . Silvestro et al. 2 use a novel methodology to model past angiosperm diversity based on a Bayesian Brownian Bridge model of fossil finds assigned to extant families, concluding that a Cretaceous origin is vanishingly unlikely. However, their results strongly conflict with the known temporal distribution of angiosperm fossils, and, while we agree that statistical analysis aids interpretation of the fossil record, here we show the conclusions of Silvestro et al. 2 are unsound.

S2 Open Access 2020
Pennaraptoran Theropod Dinosaurs Past Progress and New Frontiers

M. Pittman, Xing Xu

An unabated surge of new and important discoveries continues to transform knowledge of pennaraptoran biology and evolution amassed over the last 150+ years. This chapter summarizes progress made thus far in sampling the pennaraptoran fossil record of the Mesozoic and Paleocene and proposes priority areas of attention moving forward. Oviraptorosaurians are bizarre, nonparavian pennaraptorans first discovered in North America and Mongolia within Late Cretaceous rocks in the early 20th century. We now know that oviraptorosaurians also occupied the Early Cretaceous and their unquestionable fossil record is currently limited to Laurasia. Early Cretaceous material from China preserves feathers and other soft tissues and ingested remains including gastroliths and other stomach contents, while brooding specimens and age-structured, singlespecies accumulations from China and Mongolia provide spectacular behavioral insights. Less specialized early oviraptorosaurians like Incisivosaurus and Microvenator remain rare, and ancestral forms expected in the Late Jurassic are yet to be discovered, although some authors have suggested Epidexipteryx and possibly other scansoriopterygids may represent early-diverging oviraptorosaurians. Long-armed scansoriopterygids from the Middle-Late Jurassic of Laurasia are either early-diverging oviraptorosaurians or paravians, and some have considered them to be early-diverging avialans. Known from five (or possibly six) feathered specimens from China, only two mature individuals exist, representing these taxa. These taxa, Yi and Ambopteryx, preserve stylopod-supported wing membranes that are the only known alternative to the feathered, muscular wings that had been exclusively associated with dinosaurian flight. Thus, scansoriopterygid specimens—particularly those preserving soft tissue—remain a key priority for future specimen collection. Dromaeosaurids and troodontids were first discovered in North America and Mongolia in Late Cretaceous rocks. More recent discoveries show that these animals originated in the Late Jurassic, were strikingly feathered, lived across diverse climes and environments, and at least in the case of dromaeosaurids, attained a global distribution and the potential for aerial locomotion at small size. 1 Vertebrate Palaeontology Laboratory, Division of Earth and Planetary Science, the University of Hong Kong, Hong Kong. 2 Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology & Paleoanthropology, Beijing; and CAS Center for Excellence in Life and Paleoenvironment, Beijing. 3 Department of Earth and Environmental Sciences, University of Minnesota, Minneapolis, MN. 4 Department of Earth Sciences, University of Cambridge, Cambridge. 5 School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, U.K. 6 Department of Anatomical Sciences, Stony Brook University, Stony Brook, NY. 7 Division of Paleontology, American Museum of Natural History, New York. 38 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY NO. 440

41 sitasi en
DOAJ Open Access 2021
An assemblage of giant aquatic snakes (Serpentes, Palaeophiidae) from the Eocene of Togo

Georgios L. Georgalis, Guillaume Guinot, Koffi Evenyon Kassegne et al.

Abstract We here describe a monospecific assemblage of giant aquatic snakes from the middle Eocene of Kpogamé, Togo. The material, consisting of large isolated vertebrae, is referred to Palaeophis africanus, an enigmatic palaeophiid species, which was so far otherwise known only from a limited number of vertebrae from the middle Eocene of Nigeria and Angola. Material from the late Eocene of the eastern USA that had been referred to the same species, is here instead considered too fragmentary for species-level determination and Palaeophis africanus is thus so far restricted to Africa. With the aid of micro-CT scanning, we present 3D models of 17 vertebrae, pertaining to different portions of the vertebral column. We provide detailed comparisons of the new material with all named African species of the genus Palaeophis. A tentative diagnosis of Palaeophis africanus is provided. With more than 50 vertebrae, the new Togolese specimens represent the most abundant known material attributed to Palaeophis africanus and significantly enhance our knowledge of the vertebral anatomy and intracolumnar variation for this taxon. Furthermore, this adds to the, as yet, extremely scarce fossil record of squamates from central western Africa, a region where Paleogene herpetofaunas are only rather poorly known.

Fossil man. Human paleontology, Paleontology
DOAJ Open Access 2020
Sedimentary organic matter from a cored Early Triassic succession, Georgetown (Idaho, USA)

Elke Schneebeli-Hermann, Borhan Bagherpour, Torsten Vennemann et al.

Abstract The plant fossil record from Lower Triassic sedimentary successions of the Western USA is extremely meager. In this study, samples from a drill core taken near Georgetown, Idaho, were analyzed for their palynological content as well as their stable carbon isotope composition. The concentration of palynomorphs is generally low. The lowermost part of the drilled succession represents Dinwoody/Woodside Formation and contains spore and pollen assemblages with Permian and Early Triassic affinity. Representatives of lycophytes (Densoisporites spp., Lundbladisporites spp.) were found in the overlying Meekoceras Limestone, in agreement with middle Smithian assemblages elsewhere. Ammonoids and conodonts are extremely rare, but confirm a middle Smithian age. Bulk organic and carbonate carbon isotope composition provide a stratigraphic framework. Carbonate carbon isotope compositions are compatible with the Smithian–Spathian global trend, with a middle Smithian shift towards lower δ13C values followed by a late Smithian shift towards higher values. Bulk organic carbon isotope compositions have been influenced by changes in the constitution of organic matter. A comparison with other paired carbon isotope datasets from the same basin is difficult due to lithostratigraphic inconsistencies (Hot Springs, ID) or biochemical mediated disturbance of isotope signals (Mineral Mountains, UT).

Fossil man. Human paleontology, Paleontology
S2 Open Access 2017
A thousand bites - Insect introductions and late Holocene environments

E. Panagiotakopulu, P. Buckland

The impact of insect species directly associated with man-made habitats and human dispersal has been, and remains globally significant. Their early expansion from their original niches into Europe is intrinsically related to discussions of climate change, origins of domesticated plants and animals, the spread of agriculture and infectious diseases. The Holocene fossil records of the dispersal of three storage pest species, Sitophilus granarius, Oryzaephilus surinamensis, and Tribolium castaneum, the housefly, Musca domestica, and the human flea, Pulex irritans from 221 sites have been mapped ranging from the Near East to Europe and from the Neolithic to the post medieval period. The importance of human induced change as a driver for the spread of synanthropic faunas and the potential for the spread of disease during this process are discussed. The results show links between mobility of farming groups and distribution of synanthropic insect species and produce a roadmap for the different cultural periods of the Late Holocene based on dispersal of these synanthropic insects. During the Neolithic, the first wave of insect introductions shows the northern European frontiers of storage of cereals, introduction of domestic animals and pastoralism and exchange. Pest introductions, linked with the itinerary of the Roman army, reached the most northerly parts of the Empire. During the medieval period, the insect records indicate further expansion and changes which parallel the spread of epidemic diseases like Plague. Understanding the timing and the rates of change of synanthropic insects provides key information about the development of the homogenised and highly anthropogenic environments in which we live today.

36 sitasi en Biology

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