Here we present a comprehensive revision of the phylogeny of Cenozoic planktonic foraminifera. It integrates stratigraphic ranges, morphological traits and evolutionary relationships, resulting in an updated phylogenetic framework. The work expands the previous taxonomic coverage to include microperforate clades, adding 136 morphospecies and 29 new genera, while removing 15 previously included species. Stratigraphic ranges have been calibrated to the latest Geologic Time Scale (GTS2020), providing a more accurate timeline for evolutionary events. The digital phylogeny visualization using TimeScale Creator allows users to interact with these data, including morphospecies images and ecological information, facilitating further research into macroevolutionary processes. This resource provides a valuable platform for exploring biodiversity dynamics and species responses to environmental change throughout the Cenozoic and serves as a framework for integrating fossil and molecular data.
Trace fossils are vital for studying organism-environment interactions in deep time. However, due to uncertainties of the tracemakers, ichnotaxonomy remains independent of biological affinity and relies instead on ichnotaxobases - diagnostic features that inform on construction and function. Previous analyses of the trajectories of trails have emphasized various morphological traits, such as straight or looping paths, meanders, branches or self-overcrossing. Here we introduce a new criterion for classifying trace fossils: trajectory smoothness. Defined mathematically, smoothness measures the continuity of a curve's derivative and reflects the fluency of movement. Smooth traces suggest intentionality and directionality, commonly linked with slender-bodied tracemakers, whereas unsmooth traces with abrupt turns suggest short or round-bodied producers. Applying epsilon-delta definitions and spectral analyses, we identify smooth trajectories in the ichnotaxa Cochlichnus anguineus, C. luguanensis, Gordia marina, G. nodosa, Helminthopsis abeli, H. granulata, H. tenuis, Parapsammichnites pretzeliformis, Psammichnites gigas and Spirodesmos archimedeus. In contrast, Helminthopsis hieroglyphica, Psammichnites plummeri and P. implexus exhibit unsmooth trajectories. Helminthoidichnites is reviewed, and the type ichnospecies H. tenuis Fitch, is distinguished from H. irregularis isp. nov., as the former exhibits a smooth trajectory whereas the latter does not. Similarly, specimens of Gordia displaying unsmooth trajectories are relocated within G. angularis isp. nov. The concept of trajectory smoothness in ichnology allows us to unravel significant encrypted biological and evolutionary information about the producers (e.g. locomotory mode, body profile) and enhances the importance of robust ichnotaxonomic practices in untangling animal behaviour evolution in deep time.
The new aeduellid Franchessella pohlcremeri gen. et sp. nov. from the Permian of France is described here in detail. It is based on well-preserved specimens including the holotype, three paratypes and 25 referred specimens (one preserved in a Discosauriscus coprolite revealed by synchrotron imaging), all originating from the early Permian of the Franchesse Lagerst & auml;tte, Bourbon-l'Archambault Basin (Allier). This new taxon is characterized by a unique combination of features such as a divided rostral; five posterior infraorbitals; a trapezoidal suboperculum; two branchiostegal rays with the ventral one being larger; straight lepidotrichia sutures; lepidotrichia ornamented with ridges; and concentric ridges on scales without serration on the posterior margin. The specimens described here represent different growth stages, from osteologically immature to mature individuals, allowing us to reveal the ontogeny of this new taxon. A phylogenetic analysis shows Franchessella pohlcremeri gen. et sp. nov. early-diverging within Aeduellidae, between Puertollanichthys from Spain and 'Neslovicella' elongata from Czech Republic and Germany. This phylogenetic position, together with the well-preserved Franchessella pohlcremeri gen. et sp. nov., provides new insights into the evolution of Carboniferous and Permian actinopterygians, particularly of their rostral and clavicular regions: the progressive disappearance of sensory canals in the rostral region of aeduellids and the acquisition of a large dorsal process in the clavicle combined with an ovoid cleithrum in Aeduelliformes. Finally, this new aeduellid adds to the faunal diversity of the Franchesse locality, which corresponded to a calm lakeshore deposit in the Variscan Belt during the Permian. https://zoobank.org/urn:lsid:zoobank.org:pub:C3FC99AF-7AEC-4D80-8EE0-3759AFCA276E
The non-marine deposits of the Campanian-early Maastrichtian Cabullona Group (north-eastern Sonora, north-western Mexico) have yielded abundant fossils of continental vertebrates, including dinosaurs. However, this dinosaur fauna has yet to be studied in detail. We describe three partial hadrosaurid specimens from two localities (Arroyo del Alamito and Puerto Viejo) in the Fronteras Municipality of Sonora. All three localities correspond to the middle Campanian strata of the lower part of the Fronteras section of the Cabullona Group. The specimens are represented by partial axial and appendicular elements. The most complete individual (2997 PM 1) was collected at Puerto Viejo and consists of several axial elements, a partially complete pelvic girdle and hindlimb fragments. The parsimony phylogenetic analysis positioned the three Fronteras specimens deeply nested within the speciose saurolophine tribe Kritosaurini, as members of a subclade so far restricted to Patagonia, Argentina (here informally referred to as 'secernosaurs'). Thus, the Fronteras hadrosaurids represent the first record of secernosaurs outside South America, greatly extending their biogeographical distribution to Late Cretaceous southern Laramidia. Inference of ancestral areas for the clades recovered in the phylogeny supports the hypothesis that hadrosauroids dispersed to South America via Southern Laramidia.
In this study, we present the first comprehensive description of the skeletal morphology of the freshwater-tolerant ray †Myledaphus bipartitus, a Late Cretaceous batomorph known from North America. These new data are based on an exceptionally well-preserved specimen from the Campanian of the Dinosaur Park Formation in Alberta, Canada, which provides valuable morphological details previously lacking for this taxon. A detailed morphological analysis was conducted, which revealed a unique combination of plesiomorphic and derived characters. Phylogenetic analyses provide support for the placement of †M. bipartitus within the order Rhinopristiformes, a group that includes modern guitarfishes and sawfishes. As the oldest known freshwater-tolerant representative of Rhinopristiformes, †M. bipartitus thus offers novel insights into the early ecological diversification of this group. The present study underscores the broader necessity for comprehensive morphological and systematic research on Late Cretaceous batomorphs. Nevertheless, the obtained results demonstrate the value of combining detailed morphological data with rigorous phylogenetic methods to elucidate the evolutionary history of extinct and extant batomorph lineages.
Reptiles are currently represented by turtles, archosaurs (crocodylians and birds), and lepidosaurs (lizards, snakes and the tuatara). However, these groups represent only a fraction of the known diversity of crown reptiles throughout geological time, and the evolutionary origin of modern reptiles remains a major outstanding topic in vertebrate systematics. The molecular consensus is that turtles are more closely related to archosaurs than to lepidosaurs, but this does not consider the many extinct neodiapsids that also have their origin close to the base of the reptile crown. Great progress has been made on this subject in recent decades through the detailed study of the anatomy and systematics of Permian and Triassic reptile fossils. Nevertheless, there is still no consensus on reptile interrelationships near the origin of the three major modern reptile clades. Here, we review the current state of systematic research for Permo-Triassic lepidosauromorphs, archosauromorphs, pantestudines, sauropterygomorphs, ichthyosauromorphs, thalattosaurs, choristoderes, weigeltisaurids, drepanosauromorphs, and 'younginiforms', and provide an outlook for future efforts for these groups. Addressing this systematic question is complicated by the rarity of relevant fossils for some groups and the inherent challenges of studying the phylogenetic relationships of evolutionary radiations. However, increased research efforts, including continuous new fossil discoveries and detailed morphological studies, especially those aided by micro-computed tomography, are likely to help resolve some of these issues. Furthermore, there is a desire for comprehensive morphological character-taxon matrices focusing on this part of the reptile tree, resembling in scope and approach those already available for other major lineages, such as Archosauromorpha and Lepidosauromorpha.
The fossil remains here studied include several osteoderms from the dorsal carapace of a Dasypodinae armadillo, recovered from the Letrero Formation (c. 9 Ma) in the area of Nab & oacute;n, southern Ecuador, by an interdisciplinary team from the Escuela Polit & eacute;cnica de Quito (Ecuador) and CONICET (Argentina). The unique combination of characters observed in this new material indicates the existence of a new genus and species. Such features include large dorsal foramina restricted to mobile osteoderms probably related to a highly developed glandular system; serrated borders of the articular portion of mobile osteoderms; and rectangular fixed osteoderms with a poorly defined ornamentation pattern including long and narrow central figures. The cladistic analysis performed in this study recovers the new genus as the sister group to a clade of late-diverging dasypodines and Plesiodasypus colombianus as the most basal Dasypodinae. This result is morphologically supported by the very different morphologies of both fixed and mobile osteoderms of Plesiodasypus and Anadasypus, compared to the analysed taxon. Interestingly, a similar diversity pattern is recorded for the Middle Miocene of La Venta, where two very divergent genera co-occur at the same locality. This new endemic armadillo from Ecuador increases the paleontological knowledge of the Neogene at lower latitudes in South America while revealing a complex early evolutionary history of Dasypodinae in the tropics. Also, it provides new data on the hypothesis of provincialism of the faunas of Nab & oacute;n. https://zoobank.org/urn:lsid:zoobank.org:pub:1EF486CE-9D7C-47EF-8E4F-DFD83969921F
The evolution of Mustelidae has been a topic of debate, obscured by a complex system of convergences between phylogenetically distant groups. In this work, we present a new genus and species of mustelid, Archaeomeles neglecta gen. et sp. nov., from the classical Turolian locality of Pikermi (Greece, Late Miocene, MN12). The material consists of a skull with the associated mandible and shows distinct features that clearly differentiate it from all other known mustelid genera. These characteristics include a long and narrow rostrum, the absence of developed sagittal and supraorbital crest, relatively slender mandibular corpus, enamel folds on the lower canines, the wide P3 and p4, and the moderately enlarged M1 talon and m1 talonid. Morphometrical comparisons and phylogenetic analysis suggest that Archaeomeles is a stem member of the Melinae along with the other Turolian mustelids Promeles, Polgardia and Melodon from Eurasia. Ecomorphological comparisons indicate intermediate dietary habits between the plesiomorphic gulonines and the derived extant badgers, suggesting a diet that is based on small vertebrates and invertebrates as well as plant material. https://zoobank.org/urn:lsid:zoobank.org:pub:27B0ED3B-4653-45EA-88E2-79A134B067E0
The Middle Devonian (Givetian) locality of Red Hill, Nevada has produced tetrapodomorph materials that were described as two species, Tinirau clackae and Bruehnopteron murphyi, an elpistostegalid and tristichopterid, respectively. An overlapping set of specimens were used in both descriptions, resulting in a long-standing taxonomic issue and causing substantial inconsistencies within the literature. A renewed effort to understand the palaeoenvironment of the Devonian Red Hill, Nevada and resumed fieldwork at the locality motivated this taxonomic reassessment, prompting all relevant materials to be observed in totality. Aided by & micro;CT scans and microscope observation, we redescribed the materials and clarified the discrepancies found in the previous two separate descriptions. The reviewed osteology has led to this taxonomic revision, revealing that all the specimens belong to a single species, Tinirau clackae, following the principle of priority. Detailed examination of cranial features, particularly dentition and skull roof morphology, indicate these specimens align more closely with tristichopterids than elpistostegalids. In the parsimony phylogenetic analysis, T. clackae and Eusthenopteron jenkinsi are sister taxa and are the second-earliest-diverged tristichopterid lineage. In the Bayesian phylogenetic analysis, T. clackae is positioned as the fourth-earliest-diverged member of Tristichopteridae, following Tristichopterus alatus, E. foordi and E. jenkinsi. Consistently across analyses, T. clackae is recovered as an early-diverged tristichopterid with high support. An extensive review of all the Red Hill, Nevada specimens has not only clarified the taxonomic issue but will establish a foundation for comparative morphology and ecology studies involving relevant groups of tetrapodomorphs.
Current knowledge of the family Ursidae in Venezuela is presented, including the re-examination of previously described specimens and the formal description of UNEFM-CIAAP-1499 from Taima-Taima in the western part of the country. This specimen was studied through detailed morphological comparisons combined with phylogenetic analysis, incorporating 70 discrete characters of tremarctine bears, which consistently places UNEFM-CIAAP-1499 within the extinct species Arctotherium wingei. The available evidence indicates that A. wingei represents the only confirmed extinct Arctotherium in the region. This taxon, the smallest member of the genus, is documented in Bolivia, Brazil, Mexico and Venezuela. In Venezuela it has been found in the localities of Muaco, Cueva del Gu & aacute;charo, El Breal de Orocual, El Mene de Inciarte, and Taima-Taima, ranging in age from the Late Pleistocene to the Holocene. Furthermore, a historical record attributed to Tremarctos ornatus underscores the formerly broader distribution of the spectacled bear, today restricted to the Andes. Collectively, the Venezuelan fossil record provides significant insights into the evolutionary history, palaeobiogeography, and range dynamics of tremarctine bears in the context of faunal evolution in northern South America.
The Brachiopoda were one of the most successful groups of marine invertebrates during the Palaeozoic Era, exhibiting exceptional diversity and abundance. Linguloid brachiopods (superfamily Linguloidea), initially characterized by an epibenthic mode of life in the Cambrian, underwent substantial diversification during the Ordovician, including the emergence of infaunal forms. This interval marks the peak of their morphospace occupation and ecological diversification. To gain a deeper understanding of the ecological evolution of linguloid brachiopods, a comprehensive investigation of their morphological and anatomical evolution is essential. Here, we report a linguloid brachiopod species from the Upper Ordovician (Sandbian) Pingliang Formation at the Xilinggou section, southern Ordos Basin, North China Platform. Using geometric morphometrics, morphospace occupation was visualized for this species and Anomaloglossa porca, the latter of which was the most recently documented linguloid brachiopod in this section. Results indicate that the two species occupy different areas of morphospace, and the new linguloid brachiopod is assigned to Pseudolingula quadrata, which represents the first report of Pseudolingulidae from the North China Platform. Pseudolingula quadrata exhibits a clearly defined visceral area and preserves complete impressions of the musculature and mantle canal system. The absence of dorsal vascula media within the mantle canals indicates a close similarity to extant infaunal taxa. Based on geometric morphometric analysis and anatomical examination of linguloid brachiopods from the Cambrian to the present, our results not only reinforce the establishment of Pseudolingulidae at the family level, but also demonstrate significant modifications in shell shape and mantle canals that indicate their transition from an epifaunal to an infaunal lifestyle, providing critical insights into their evolutionary trajectory and ecological evolution.
The Middle Permian reptile Eunotosaurus africanus is a key taxon for understanding reptile evolution because it has been proposed to be one of the earliest stem turtles, but it could alternatively represent an early sauropsid. Alternative evolutionary interpretations are based on morphological character observations, and comparative anatomy of previously undocumented body parts may yield novel character evidence. Based on a previously unreported specimen of Eunotosaurus africanus, we provide descriptions of its inner ear anatomy, which we compare to a diversity of amniotes including turtles, millerettids and novel segmentations of Youngina capensis and Champsosaurus lindoei. The inner ear of Eunotosaurus africanus has plesiomorphic neodiapsid inner ear features that contrast with turtle ear morphology, including a radius of curvature of the anterior semicircular canal (ASC) that is larger than that of the posterior semicircular canal (PSC), narrow intercanal angles, slender vertical semicircular canals, and a bend in the central section of the PSC. Eunotosaurus africanus shares with turtles a large common crus cross-section and a thickened lateral semicircular canal. We provide a landmark-based comparison of amniote labyrinth shapes, which shows principal differences in the semicircular canals of birds, mammals and turtles as end members of a gradient of semicircular canal geometries. Other extant amniote groups (crocodiles, lepidosaurs), fossil lineages (e.g. sauropterygians, captorhinids, millerettids, younginiforms, varanopids, Eunotosaurus africanus) and stem lineages of extant groups (e.g. pterosaurs, non-avian dinosaurs, phytosaurs, other extinct pseudosuchians, mosasaurs, 'pelycosaurs', dicynodonts) show semicircular canal geometries that are generally intermediate between extreme shapes of birds, mammals and turtles, so that the entire morphospace shows gradational morphologies. The observed variation provides evidence of convergent evolution of labyrinth features, but also suggests phylogenetic signal is widespread in labyrinth morphology and that bird, mammal, and turtle labyrinth shapes may have evolved from a plesiomorphic shape that was retained in many reptilian stem lineages.
A new saurolophine hadrosaurid, Gongshuilong fanwei, is named and described here based on a series of largely disarticulated bone elements from the middle of the Upper Cretaceous Lianhe Formation in Ganzhou City, Jiangxi Province, South China. This taxon is diagnosed by a unique combination of traits, including an elevated anterodorsal process of the maxilla which is slightly longer than the anteroventral one, dentary tooth crowns ornamented with a median primary ridge and relatively small marginal denticles, an extremely truncated edentulous region of the dentary, an anteroposteriorly wide ventral process of the postorbital, a poorly developed deltoid ridge on the lateral surface of the scapula, and markedly elongate, posterodorsally directed neural spines of the posterior caudal vertebrae that are moderately recurved. Phylogenetic analysis yielded a polytomy at the base of Brachylophosaurini within Saurolophinae, which is formed by Wulagasaurus, Gongshuilong, Acristavus and the clade of Maiasaura + (Probrachylophosaurus + Brachylophosaurus). Gongshuilong is the first reported hadrosaurid genus from South China and is the second taxon of Brachylophosaurini found in Asia. Its discovery increases the possibility of the Asian origin for Saurolophinae and Brachylophosaurini, based on biogeographical analysis for ancestral areas using the Bayesian binary method. https://zoobank.org/urn:lsid:zoobank.org:pub:221FCD08-59F6-4637-9BC5-D50EB904EE2C
Pachycormidae is a Mesozoic clade of stem-teleost actinopterygians outside of, but closely related to, Teleostei - the grouping that comprises more than 95% of living fish species and almost half of all extant vertebrate species. The first named pachycormid genus, Sauropsis Agassiz, 1832, is revised based on the historic type species Sauropsis longimanus Agassiz, 1843 from the Upper Jurassic Solnhofen Archipelago of Bavaria. Under the current definition, Sauropsis represents a non-character-based assemblage of historic and ambiguous pachycormid fishes ranging from the Early to Late Jurassic and characterized predominantly by pointed marginal teeth and elongate body shape. Here, we present the first comprehensive description of Sauropsis longimanus and critically review all species previously assigned to Sauropsis. We propose that only the type species, Sa. longimanus, should be retained in Sauropsis, along with a second as yet undescribed species from the Callovian of England. Our revised definition for the genus defines Sauropsis as a small hypsocormine pachycormid with an elongated body (head length = 25% standard length), unpaired fins opposed, with the origin of the dorsal fin very slightly in advance of the anal fin, two or three vertical scale rows per vertebral segment, scales without peg-and-socket articulation, and two independent lateral lines which converge in the supracleithrum. The spelling of Sauropsis longimanus is corrected to Sauropsis longimana to match the gender of the genus following article 31.2 of the International Code of Zoological Nomenclature. A new combination, Simocormus depressus comb. nov., is proposed for a second Upper Jurassic species from Solnhofen, previously described as 'Sauropsis' depressus. Phylogenetic analysis resolves Sa.longimana as an early-diverging member of the subfamily Hypsocorminae and sister to the Gondwanan genus Kaykay. We additionally resolve a new unnamed clade of pachycormids containing Simocormus macrolepidotus, Pseudoasthenocormus retrodorsalis and Simocormus depressus comb. nov. that holds an early-diverging position relative to Asthenocorminae + Hypsocorminae, and discuss the evolutionary implications.https://zoobank.org/urn:lsid:zoobank.org:pub:756F6544-0F58-4C4D-B3A0-926AE7251560
The systematics and evolution of Cambrian euarthropods have undergone a major transformation in recent years owing to the continued discovery of new species from sites with exceptional preservation, redescription of established taxa through new material and/or imaging methodologies, and a consistent push towards broadly sampled phylogenetic datasets. These efforts have yielded impressive results, including a more comprehensive view of Cambrian euarthropod diversity and better understanding of their detailed morphology. The progress has effectively narrowed the Deuteropoda gap, namely the large accumulation of derived characters that evolved during the transition from soft-bodied lower stem-group euarthropods (lobopodians, radiodonts) into the upper stem-group euarthropods typified by deutocerebral first appendages and multisegmented heads. However, it has also caused a shift in our understanding of Cambrian euarthropod interrelationships and the higher affinities of several clades, directly impacting hypotheses on the origin and initial radiation of this phylum. Whereas the composition of lower stem-group Euarthropoda has remained stable, that of the upper stem-group has changed drastically with several clades now regarded as members of the group-crown, most notably hymenocarines, fuxianhuiids, artiopods, and (possibly) megacheirans. A notable consequence of these phylogenetic adjustments is the shortening of the upper stem-group, now consisting of forms with a raptorial first appendage including isoxyiids and Kylinxia. The resulting “short stem-lineage” scenario is consistent with the diversification dynamics of unusually large clades, notably that the crown-group will evolve exceptionally quickly. I propose that the “short stem-lineage” scenario reconciles the minimum estimates for the appearance of stem-group euarthropods based on the Fortunian trace fossil record (ca. 537 Mya), the subsequently prompt evolution of the crown-group based on the estimated origin of trilobites (ca. 535 Mya), and the predicted rapid initial diversification of the stem-group. Finally, I highlight the importance of resolving the ancestral state of the deutocerebral first appendage of Deuteropoda in order to polarize the macroevolution of Cambrian euarthropods.
Lepidosauromorphs account for roughly a third of the living diversity of land vertebrates and yet their origin and early evolutionary history remain highly contentious. The fossil record of early lepidosauromorphs has historically been very poor, but this has changed in recent years with new taxa having been reported from Europe and North and South America, such as the contributions from Vellberg, south-western Germany. Here, we describe four new early lepidosauromorph taxa from the same locality (Airistagiz seegisi, Hohlachia multidens, Klainjosaura staroskalja, gen. et sp. nov. and an unnamed taxon), raising the number of known lepidosauromorphs from three to seven. The new taxa add to the anatomical diversity of early lepidosauromorphs, in both cranial and postcranial regions, with suspensorium and tooth implantation features indicating the presence of an ecological mechanism that could explain their sympatric existence without direct competition. Variations in temporal morphology may represent different ranges of mobility, indicating that key modifications necessary for streptostyly possibly appeared before the origin of crown lepidosaurs - and certainly before crown squamates. The importance of the Central European Basin for the origin of several reptile groups like archosauromorphs and turtles had already been demonstrated with iconic fossils like Protorosaurus and Pappochelys, but these new findings now include lepidosauromorphs, the second-most diverse group of amniotes, and highlight the importance of the systematic exploration of small taxa in Lagerst & auml;tten. https://zoobank.org/urn:lsid:zoobank.org:pub:95E38B1F-ADAD-4A8F-B45B-955FA7F3A196
We herein describe a new crocodile, Crocodylus lucivenator sp. nov., from palaeoanthropological sites in the Pliocene Hadar Formation in north-eastern Ethiopia. It shares derived features and plesiomorphic states with two Pleistocene species of Crocodylus from East Africa. Conversely, C. lucivenator bears a midline boss on the dorsal surface of the rostrum similar to those of modern Neotropical crocodiles and late Miocene crocodiles from Libya and Kenya. A boss is also present on Pliocene specimens from Kanapoi in Kenya previously referred to C. thorbjarnarsoni. Some C. lucivenator also have a more substantial prenarial rostrum than other Palaeoafrican Crocodylus, though not to the same extent as in extant Crocodylus, and its expression is variable. Phylogenetic analysis supports a close relationship between C. lucivenator, Kanapoi Crocodylus, C. anthropophagus, C. thorbjarnarsoni, and fossils from the Turkana Basin previously misreferred to C. checchiai. A close relationship with Neoafrican Crocodylus is rejected, reinforcing a comparatively recent arrival for Neoafrican Crocodylus in East Africa. Crocodylus lucivenator and the Kanapoi form are very similar, but an exclusive relationship is not unambiguously supported in our analysis. The phylogenetic placement of the Palaeoafrican clade depends on how one regards the prenarial rostrum, and positions outside crown Crocodylus or close to the Neotropical clade can be equally optimal. One mandible preserves pathological structures consistent with injuries sustained during intraspecific combat. Crocodylus lucivenator appears to have been the only crocodylian in the Hadar Formation, while coeval deposits in the Turkana Basin preserve as many as four species. The reason for this disparity is unclear.https://zoobank.org/urn:lsid:zoobank.org:pub:27E5A2F8-E240-44F3-B4DF-8CF35EA5F6B6
