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We describe new macro- and microfossils recovered on a field expedition to the North Quarry of Poponguine, a locality in western Senegal that spans the Late Cretaceous through the Early Paleogene, albeit with a likely unconformity at the base of the Danian. Newly discovered macrovertebrates from the Maastrichtian Cap de Naze Formation include pycnodonts, dyrosaurids, and chelonians, the latter two the oldest and first Cretaceous representatives of these clades from Senegal. Screenwashing of this deposit revealed that the matrix also consists of abundant microscopic biological clasts comprising osteichthyan vertebrae, spines, and cranial fragments, shark dermal denticles, invertebrates, and numerous ovoid coprolites among other fragments. These microfossils document a much less conspicuous portion of the paleobiodiversity. We describe the stratigraphy of this new locality and incorporate it into a new correlated section that ties together three other Late Cretaceous–Early Paleogene fossiliferous localities of the Senegalese-Mauritanian Basin. The presence of fossiliferous Danian rocks, which are notably rare in West Africa, is elucidated in our section, which synthesizes prior geological and paleontological work around Poponguine and in the nearby coastal region of Ndayane. Primarily dated using the biostratigraphy of ostracods and foraminiferans, the correlated rock units include the Paki and the Cap de Naze Formations of the Late Cretaceous Diass Group and the Ndayane and the Poponguine Formations of the Paleocene Cap-Vert Group, deposits that capture ancient near shore marine environments. The localities described, although separated by only a few kilometers, exhibit dramatic differences in thickness across faulted blocks of the Diass Horst. Dyrosaurids, which are common fossils in nearshore marine outcrops of West Africa, have been hypothesized to be of African origin and to have dispersed to South America in the Late Cretaceous. This dyrosaurid specimen, although fragmentary, documents a western extreme in the geographic range of African dyrosaurids where the clade would have been well situated for broader trans-Atlantic dispersal. [ABSTRACT FROM AUTHOR]

Background: The "woody clade" in Saxifragales (WCS), encompassing four woody families (Altingiaceae, Cercidiphyllaceae, Daphniphyllaceae, and Hamamelidaceae), is a phylogenetically recalcitrant node in the angiosperm tree of life, as the interfamilial relationships of the WCS remain contentious. Based on a comprehensive sampling of WCS genera, this study aims to recover a robust maternal backbone phylogeny of the WCS by analyzing plastid genome (plastome) sequence data using Bayesian inference (BI), maximum likelihood (ML), and maximum parsimony (MP) methods, and to explore the possible causes of the phylogenetic recalcitrance with respect to deep relationships within the WCS, in combination with molecular and fossil evidence. Results: Although the four WCS families were identically resolved as monophyletic, the MP analysis recovered different tree topologies for the relationships among Altingiaceae, Cercidiphyllaceae, and Daphniphyllaceae from the ML and BI phylogenies. The fossil-calibrated plastome phylogeny showed that the WCS underwent a rapid divergence of crown groups in the early Cretaceous (between 104.79 and 100.23 Ma), leading to the origin of the stem lineage ancestors of Altingiaceae, Cercidiphyllaceae, Daphniphyllaceae, and Hamamelidaceae within a very short time span (∼4.56 Ma). Compared with the tree topology recovered in a previous study based on nuclear genome data, cytonuclear discordance regarding the interfamilial relationships of the WCS was detected. Conclusions: Molecular and fossil evidence imply that the early divergence of the WCS might have experienced radiative diversification of crown groups, extensive extinctions at the genus and species levels around the Cretaceous/Paleocene boundary, and ancient hybridization. Such evolutionarily complex events may introduce biases in topological estimations within the WCS due to incomplete lineage sorting, cytonuclear discordance, and long-branch attraction, potentially impacting the accurate reconstruction of deep relationships. [ABSTRACT FROM AUTHOR]

There are few studies focused on spore and pollen clumps in paleopalynological samples, and these are only reports from the Northern Hemisphere. These aggregates may be of animal or floral origin. The goal of this contribution is to provide the first detailed study of spore and pollen clumps from the Southern Hemisphere, and to discuss their possible origin, botanical affinities, and pollination modes, based on their morphological characteristics, preservation and comparison with putative living representatives. Three fern spore clumps and 18 angiosperm pollen clumps were recognized in Maastrichtian-Danian La Colonia Formation sediments that outcrop at Chubut Province, Patagonia, Argentina. Most clumps are monospecific and composed of undamaged elements but some of them have two types of spore/pollen with corroded and/or fragmented exines. These findings represent the most diverse and abundant record of fern and angiosperm clumps from the Late Cretaceous and early Paleocene so far known from South America and the Southern Hemisphere. These results are indicative of the need for comprehensive large-scale studies on pollination of modern taxa and careful processing of palynological samples to lessen the already large bias in paleopalynological interpretations. The paucity of information on clumps in the fossil record has impaired our comprehension of dispersion/pollination in deep time. [ABSTRACT FROM AUTHOR]

Summary: The storied structure in wood anatomy is considered derived and highly specialized, and is present in some related families. The first records of this character are from the Cretaceous, but it is scarce in the Cretaceous and Paleocene, and apparently absent until the Eocene in the temperate Southern Hemisphere. Using standard methodology, we describe the anatomy of a fossil wood from the early Paleocene of Patagonia (Salamanca Formation). The fossil wood, assigned to a new genus and species Elizabethiaxylon patagonicum related to the Malvaceae, is characterized by its diffuse-porous wood, solitary vessels, simple perforation plates, apotracheal banded axial parenchyma, and mostly biseriate storied rays. The storied structure in this wood is one of the oldest records from Gondwana. [ABSTRACT FROM AUTHOR]

This paper discusses the current state of knowledge of Paleogene stratigraphy of Kaliningrad Oblast, the age of local stratigraphic units and the duration of possible gaps in deposition and proposes trends for future regional Paleogene stratigraphy. The Paleocene Chistoozerskaya and Lubava formations in total probably correspond to the Danian–Selandian on the basis of foraminiferal zonation, but their relationship is not entirely clear. The Zaostrovskaya Formation probably corresponds to the upper Thanetian, but its fossil record is very poor. The Sambian Formation corresponds to the Ypresian according to foraminifera, but its precise stratigraphical interval remains insufficiently substantiated. The Alka Formation is presumably late Lutetian–early Bartonian. The age of the Prussian Formation is emended based on dinocysts as early–late Priabonian, while the Palvé Formation is now dated as the latest Priabonian. The Kurshskaya Formation corresponds to the uppermost Eocene–Oligocene–?lower Miocene. The problem of the recognition and duration of hiatuses between formations remains relevant. [ABSTRACT FROM AUTHOR]

Premise of research. Burseraceae is represented by a large number of fossils from the Cenozoic sedimentary succession and has a disjunct distribution today in the southern part of North America, Africa, Europe, and Asia. However, the family has a poor fossil record in deep time, making hypotheses concerning its origin and dispersal difficult to evaluate. Here, we report the occurrence of reproductive organs (fruit and flower) attributable to modern Burseraceae from the probable latest Maastrichtian (Late Cretaceous) to earliest Danian (early Paleocene) sediments of the Mandla Lobe of the Deccan Intertrappean beds of Madhya Pradesh, Central India. Methodology. X-ray micro–computed tomography was used to observe three-dimensional structures. The reconstruction software takes the 2D projection images acquired by the X-ray detector and generates a 3D image represented by gray values distributed in a volumetric space. The present fruit and flower fossils are identified through morphological comparison with another fossil and extant Burseraceae. Pivotal results. The fossil pyrene corresponds in morphology with that of Burseraceae (particularly some genera of Protieae and Bursereae), while the fossil flower, with the pentamerous organization of sepals and petals and ovary and 10 stamens arranged in two whorls around a prominent intrastaminal nectary disk, is particularly similar to Protium. The fossil fruit is here described as a new species of the fossil genus Bursericarpum Reid et Chandler as Bursericarpum indicum Kumar, Manchester et Khan sp. nov. and the fossil flower as Debursera indica Kumar, Manchester, Judd et Khan sp. nov. Conclusions. The present discoveries represent the oldest reliable fossil records of Burseraceae supporting its Gondwanan origin. These fossils also provide important information for tracing possible migration pathways of Burseraceae from India to Europe after the docking of the Indian subcontinent with Eurasia during the early Eocene (55 ± 10 Ma), supporting an "out-of-India" dispersal hypothesis. Based on earlier and present records we suggest that the family might have reached Europe from India and then colonized North America (during the Eocene) in areas where it is now regionally extinct. [ABSTRACT FROM AUTHOR]

We here report on the first lizard fossils from the Deccan intertrappean strata (latest Cretaceous/Palaeocene) exposed at Kesavi, District Dhar in the Malwa Plateau of lower Narmada Valley, central India. The material is only fragmentary, but tentatively three tooth morphotypes of non-acrodontan lizards can be identified. Besides these, two oblong osteoderms, resembling paramacellodid osteoderms, are described as Squamata indet. The 4th isolated tooth is questionably referred to Squamata. Although the intertrappean deposits of the Deccan volcanic province have been explored for over three decades, lizards are scarce and many aspects remain unclear. However, the tentative absence of agamids in Kesavi and other localities yielding pre-Eocene deposits (e.g., Naskal and Kisalpuri) appears to be interesting, because a high diversity of agamids has been reported from early Eocene localities of India. There is, in contrast, a total absence of non-acrodontan lizards. The contrast between pre-Eocene and Eocene localities seems to be puzzling in the context of India's supposed physical isolation from Asia during this time. Only future researches can shed light on that. Although the material described here brings only limited new insight, it supports that non-acrodontan lizards were present in India during the latest Cretaceous/earliest Palaeocene. [ABSTRACT FROM AUTHOR]

Although liverworts (Marchantiophyta) are postulated to be one of the oldest lineages of land plants, their documented fossil record is sparse. This study describes five new fossil liverwort gametophytes, one of which bears antheridia, from the Paleocene Paskapoo Formation of Alberta, Canada. The thalli are bilaterally symmetrical, with two undissected wings that bear oppositely arranged dorsal lamellae. One specimen is dichotomously branched, and one bears clusters of antheridia along the midrib area of its dorsal surface. These characters are consistent with those of extant Petalophyllum Nees & Gottsche ex Lehm. (Fossombroniales: Petalophyllaceae), and the genus Petalophyllites gen. nov. (Fossombroniales: Petalophyllaceae) is here erected for these fossils. They are the first representatives of Petalophyllaceae and the Fossombroniales from the fossil record. Most of the specimens are in growth position. Their geologic setting and associated fossils indicate that Petalophyllites lived at the margin of a lake or pond in a habitat that may have been intermittently dry, as is also common in extant species of Petalophyllum. The well-preserved thalli and antheridia of these fossils, and their well-documented middle Paleocene age, provide new evidence of liverwort diversification at the dawn of the Cenozoic Era. [ABSTRACT FROM AUTHOR]

In the northeastern zone of the department of Boyacá, in the locality of Socha, areas with a high fossiliferous potential of microvertebrates and vertebrates, as fish, crocodiles and, particularly, turtles, of middle and upper Paleocene age of the Arcillolitas de Socha Formation have been identified. Along this sector, detailed stratigraphic sections and geological profiles were elaborated, which together with lithostratigraphic and biostratigraphic techniques, allowed us to differentiate the formation into three members and to identify the prospecting areas of two fossiliferous levels of interest, as well as a group of key sandstones located in the intermediate levels. The paleoenvironments identified for the formation indicate a lagoonal, marshy, paludal, and deltaic sedimentation for the sandstones, generally sedimented in a continental depositional environment. All the information obtained could be applied for the eventual location of fossils in prospecting and exploration in subsequent research, as well as highlighting the imperative need to strengthen local laws in favor of the protection and preservation of these paleontological deposits in the region. [ABSTRACT FROM AUTHOR]

The Paleocene Paskapoo Formation in Alberta, Canada, offers a unique opportunity to gain insight into insect diversity at that time. This fossil insect-rich formation has yielded a variety of fossil arthropod specimens, including several wings of Odonata related to the genus Alloaeschna Wighton and Wilson, 1986. Here, we demonstrate that morphological characters previously used to separate three species are instead the result of intraspecific variability. We reinforce this demonstration using two examples of high variability and plasticity in modern species of the family Aeshnidae. Accordingly, we reinterpreted the taxonomic position of Alloaeschna marklae Wighton and Wilson, 1986 syn. nov. and Alloaeschna quadrata Wighton and Wilson, 1986 syn. nov. as junior synonyms of Alloaeschna paskapooensis Wighton and Wilson, 1986. In addition, we describe the first occurrence of a zygopteran in the Paskapoo Formation, namely Albertalestes paskapooensis gen. et sp. nov. (Synlestidae). Importantly, this new taxon is the first representative of the family found in North America. We also reconstructed the relationships within the Synlestidae under Bayesian inferences with a newly assembled matrix. Finally, we discuss the biogeography of the clade considering its fossil record using parsimony ancestral state reconstruction. [ABSTRACT FROM AUTHOR]

Bauhinia s.s. is a large genus in the family Fabaceae, but its evolutionary and biogeographical history is still unclear due to the scarcity of fossil records compared to the highly diverse modern species in pantropic regions. Here, we report the earliest fossil record of Bauhinia s.s., namely Bauhinia tibetensis Y. Gao et T. Su sp. nov., based on leaves from the latest Paleocene of the southern Tibetan region. Combined with palaeoecological niche simulations and ancestral state reconstruction, the new fossils suggested a Paleocene origin of Bauhinia s.s. in the Afrotropical realm that subsequently dispersed to the Neotropical and Indomalayan realms. Bauhinia tibetensis belongs to the Asian clade of Bauhinia s.s. that reached the southern Tibetan region from the Afrotropical realm via the Kohistan-Ladakh Island Arc in the early Paleocene. This clade spread to south-eastern China during the Oligocene and entered northern India during the Neogene or earlier. The discovery of the oldest Bauhinia s.s. from what is now the southern Tibetan Plateau updates our understanding of the biogeographical history of this genus and demonstrates that the Kohistan-Ladakh Island Arc is an ancient corridor for floristic interchange between Africa and India. [ABSTRACT FROM AUTHOR]

Premise of research. Fossil infructescences of the late Paleocene Cyclocarya brownii (Juglandaceae) and winged fruits with newly recognized anatomical structure are described from Almont and Beicegel Creek, North Dakota. These fossils demonstrate that C. brownii has many similarities to extant Cyclocarya paliurus but differs in several morphological and anatomical features. Comparisons of the fossil record of Cyclocarya document the transition of characters in the evolution of the oldest extant genus of Juglandaceae. Methodology. Fossils were digitally imaged with reflected light microscopy (LM). Some specimens were embedded in Ward's Bio-Plastic synthetic resin, sectioned into wafers, mounted on microscope slides, and imaged with reflected LM. Permineralized specimens from the Beicegel Creek site were prepared with the cellulose acetate peel technique, mounted on microscope slides, and imaged with transmitted LM. Extant fruits of C. paliurus were photographed from freshly collected material. Pivotal results. Infructescences of C. brownii differ from those of modern C. paliurus in several ways. The fossils are racemes with crowded fruits borne on elongate pedicels. In contrast, extant C. paliurus has spikes bearing fewer fruits per infructescence (10 vs. 23). Fruit wall anatomy is similar to that of extant and other known fossil species of Cyclocarya but is more complex and has a distinctive idioblast layer not present in extant Cyclocarya. Fossil pollen is triporate in contrast to the tetraporate pollen in extant Cyclocarya. As in extant Cyclocarya , pollen is borne both in staminate catkins and occasionally in stamens attached to fruits. We document a fossil fruit with stamens bearing pollen. This feature, sporadic in extant Cyclocarya , was also present in the Paleogene. Conclusions. Late Paleocene C. brownii differs in comparison with extant C. paliurus and related fossil forms in infructescence architecture, fruit size and symmetry, fruit wall anatomy, and pollen aperture number. Trends in character evolution from the Paleogene to the present day include (1) changes from helically arranged, densely distributed pedicellate fruits to sessile fruits borne singly along a slender axis, (2) transition from pyramidal to round nutlets with (3) equatorial versus basal wing attachment, (4) a change in pollen aperture number from three to four, and (5) simplification of the fruit wall in extant Cyclocarya. [ABSTRACT FROM AUTHOR]

Paromomyidae are one of several families of plesiadapiforms that flourished during the Paleocene in North America soon after the extinction of non-avian dinosaurs some 66 million years ago. Although they are often among the best-represented plesiadapiforms in mammalian faunas in both North America and Europe, the early history of paromomyids is poorly understood, and their fossil record at higher latitudes is comparatively depauperate. We report here on the discovery of two new species of paromomyids from Paleocene deposits in southwestern Alberta: Edworthia greggi new species is the second known species of the basal paromomyid Edworthia Fox, Scott, and Rankin, 2010 whereas Ignacius glenbowensis new species is among the most abundantly represented species of Ignacius Matthew and Granger, 1921. These new discoveries document, for the first time, parts of the upper dentition of Edworthia, and the new species of Ignacius represents the first new, pre-Clarkforkian species of the genus to be described in nearly 100 years. A comprehensive phylogenetic analysis of nearly all known paromomyid taxa (including the new species described herein) recovered both species of Edworthia near the base of the paromomyid tree in a polytomy with Paromomys depressidens Gidley, 1923 and a paraphyletic Ignacius. The new paromomyids from Alberta not only increase the known taxonomic diversity of Edworthia and Ignacius but also add significantly to knowledge of the dental anatomy of these poorly known genera and further add to a uniquely Canadian complement of Paleocene plesiadapiforms. UUID: http://zoobank.org/a2f31cfe-09b9-4168-b09f-9d0c3d0af342 [ABSTRACT FROM AUTHOR]

Premise of research. The Anacardiaceae family is distributed throughout the vegetated continents. The fossil record indicates extensive diversification of the family during the Paleogene and, in particular, during the Eocene. Despite the abundant fossil record of this period, there are only a few reliable anacardiaceous fossils in the Paris Basin. Here, we aim to document newly recognized fossils of Anacardiaceae from the Paris Basin, understand their paleoecology, and discuss their biogeographic history. Methodology. Thirty-three lignite fruits were examined from two sites, one before and one after the Paleocene-Eocene boundary (i.e., Petit Pâtis [Rivecourt] and Le Quesnoy [Houdancourt]). The specimens were photographed, and anatomy was studied using computed tomography and histological sections. Comparative analyses were undertaken using available descriptions of fossil and modern fruits of Anacardiaceae. Pivotal results. A new species, Cyrtocarpa biapertura sp. nov., is described on the basis of a unilocular fruit with two prominent apertures present on the ventral side of the endocarp, protruding into two lacunae surrounding the locule. Taphonomic analysis indicates that this plant grew close to riverbanks. Furthermore, a new record of " Lannea " europaea (Reid and Chandler) Chandler is reported for the Eocene site. Conclusions. The occurrence of Cyrtocarpa in both the Paleocene and the Eocene floras in the Paris Basin suggests similar vegetation during both time intervals. It is likely that both floras grew under similar subtropical climates. Moreover, it appears that the early Eocene shows an enrichment of the paleodiversity of Anacardiaceae and other plant families in the Paris Basin. The presence of Cyrtocarpa documents a rarely reported disjunction between the Paleogene of Europe and the recent tropical flora of South America. [ABSTRACT FROM AUTHOR]

We describe nearly complete skeletons of basal Anseriformes from the Latest Paleocene to the early Eocene of North America and Europe. Collectively, these birds appear to be representative of anseriforms near the divergence of Anhimae and Anseres, but their exact positions relative to these clades remains uncertain. A new family, Anachronornithidae nov. fam., is erected on the basis of one of these, Anachronornis anhimops nov. gen., nov. gen. et sp., to which the others cannot be confidently assigned. The new fossils augment a growing collection of early Pan-Anseriformes, which in their diversity do not paint an unambiguous picture of phylogeny or character state evolution on the path to or within crown-Anseriformes. Anachronornis nov. gen. is similar in some aspects of both cranial and postcranial anatomy to other well-represented early Paleogene Anseriformes and members of Anseres, such as Presbyornis Wetmore, 1926. However, it exhibits a more landfowl-like bill, like that of Anhimae and unlike the spatulate bill of Anseres. Additional specimens of similar basal Anseriformes of uncertain affinities from the early Eocene of North America and Europe further complicate interpretation of character state polarity due to the mosaicism of primitive and derived characters they exhibit. [ABSTRACT FROM AUTHOR]

Sea turtles (Testudines: Chelonioidea) represent a monophyletic group with a global distribution in the fossil record, although most of our knowledge of their diversity and morphology comes from the Atlantic Ocean and Tethyan Sea (Evers and Benson 2019; Gentry et al. 2019). By contrast, the record of their evolution in the vast Pacific Basin prior to the Neogene is paltry. Late Cretaceous chelonioids are known from northern California (Parham et al. 2003), British Columbia (Nicholls 1992; Nicholls and Meckert 2002), Japan (Hirayama and Chitoku 1996), Australia (Kear et al. 2003; Kear 2006; Kear and Lee 2006), and New Zealand (Wiffen 1981), indicating they occupied at least portions of both the North and South Pacific Oceans at this time. Pacific Paleocene specimens are entirely unknown, and to date the Eocene record has been limited to chelonioids and dermochelyids (Köhler 1995a, b; Grant-Mackie et al. 2011) from New Zealand, and an informal report of a sea turtle from Oregon (Orr and Orr 2009). Here, we describe a new sea turtle fossil from the middle Eocene of California which demonstrates that members of this clade were indeed present in the North Pacific at this time. [ABSTRACT FROM AUTHOR]

Sea turtles (Testudines: Chelonioidea) represent a monophyletic group with a global distribution in the fossil record, although most of our knowledge of their diversity and morphology comes from the Atlantic Ocean and Tethyan Sea (Evers and Benson 2019; Gentry et al. 2019). By contrast, the record of their evolution in the vast Pacific Basin prior to the Neogene is paltry. Late Cretaceous chelonioids are known from northern California (Parham et al. 2003), British Columbia (Nicholls 1992; Nicholls and Meckert 2002), Japan (Hirayama and Chitoku 1996), Australia (Kear et al. 2003; Kear 2006; Kear and Lee 2006), and New Zealand (Wiffen 1981), indicating they occupied at least portions of both the North and South Pacific Oceans at this time. Pacific Paleocene specimens are entirely unknown, and to date the Eocene record has been limited to chelonioids and dermochelyids (Köhler 1995a, b; Grant-Mackie et al. 2011) from New Zealand, and an informal report of a sea turtle from Oregon (Orr and Orr 2009). Here, we describe a new sea turtle fossil from the middle Eocene of California which demonstrates that members of this clade were indeed present in the North Pacific at this time. [ABSTRACT FROM AUTHOR]

Squat lobsters within Galatheoidea are very diverse with over 1,300 extant species that live in all marine ecosystems, but their fossil record, starting in the Middle Jurassic, consists of only ~200 species. Consequently, much remains to be learned about their biodiversity, phylogeny, and paleobiogeography. We describe five new species (Galatheites sforum n. sp., Kimmeridgian, Late Jurassic, Germany; Vasconilia zapotitlanensis n. sp., Barremian, Early Cretaceous, Mexico; Eomunidopsis texcalaensis n. sp., Barremian, Early Cretaceous, Mexico; Protomunida bennickei n. sp., Danian, Paleocene, Denmark; and Protomunida eurekantha n. sp., Danian, Paleocene, Denmark) and one new genus (Tethysgalathea n. gen., Ypresian, Eocene, Italy). We further reassign Munida cretacea (Albian, Early Cretaceous, Texas, USA) to Galathea?, return Eomunidopsis? cobbani (Campanian, Late Cretaceous, Colorado, USA) to its original genus, report on the second occurrence of Vetoplautus latimarginus Robins et al., 2013 (Tithonian, Late Jurassic, Czech Republic), and reinstate Palaeomunidopsis moutieri (middle Bathonian, Middle Jurassic, France) as the oldest galatheoid known to date. The five new species, all found in limestones containing corals, increase galatheoid diversity in the fossil record by 2.5%. Finally, the common yet hitherto unrecognized Protomunida eurekantha was discovered by making casts of external molds, revealing distinct spines on the posterior margin that are more difficult to see in internal molds and specimens with cuticle due to breakage. Collecting and studying the external molds for galatheoids and other fossil decapods could yield additional cryptic species. UUID: http://zoobank.org/68a25381-65c6-4773-a4f2-71d9b0a25304 [ABSTRACT FROM AUTHOR]

Simple Summary: The deciduous shrub Comptonia is a monotypic genus of Myricaceae, which currently is distributed only in eastern North America, with a smaller range than that in other periods of the Cenozoic. By analyzing the macroscopic and microscopic characteristics of the leaves, we describe a new species of Comptonia (i.e., Comptonia hirsuta) from the Hannuoba Formation in Zhuozi, Inner Mongolia, North China. The co-occurring fruits were also studied based on their morphological characteristics, which were assigned to Comptonia tymensis. Variation in the distribution range of Comptonia indicates the influence of global cooling on the expansion of this plant. Furthermore, the Bering Land Bridge played an important role in the migration from North America to East Asia. The Thulean route may have provided an opportunity for plant exchange between western Europe and eastern North America. Moreover, the reason for the disappearance of Comptonia from China according to the analysis of the changes in both the global climate and the distribution of Comptonia fossils is also discussed. It is suggested that the climatic changes after the late Miocene and the progenitive pattern of Comptonia together caused the disappearance of Comptonia in China. Comptonia (Myricaceae) is well known as a monotypic genus living only in eastern North America; however, fossils show that the genus occurred extensively in the Northern Hemisphere during the Cenozoic. We observed dozens of Comptonia leaf fossils from the early Miocene in Zhuozi, China. The leaf architecture characteristics and epidermal features of the fossil specimens are described in detail here for the first time, and they were assigned to a new species: Comptonia hirsuta. The fruit fossils collected simultaneously from the same layer were assigned to Comptonia tymensis. The global fossil records indicate that the spatial distribution range of Comptonia reached its peak in both the Eocene and Miocene as two warm periods and then gradually decreased in the Oligocene, as well as after the late Miocene, because of the cooling global climate. Furthermore, the Comptonia taxon in East Asia may have migrated from North America via the Bering route in the late Paleocene or Eocene. Plant exchange between western Europe and eastern North America possibly occurred during the Eocene via the Thulean route. Phytogeographic variation in the Comptonia fossils from China also indicates that the reason for the disappearance of Comptonia from China may not only be due to the prolonged cooling and drying after the late Miocene, but also due to its progenitive pattern. [ABSTRACT FROM AUTHOR]

The extinct betulaceous genus Palaeocarpinus accommodates fossils with a mixture of characters shared by fruits of the extant genera Carpinus and Corylus. Originally described from the Paleocene of southeastern England, the genus has since been recognized in other parts of Europe, North America and Asia, and into the Eocene. Currently, descriptions exist for ten named Palaeocarpinus species. Here we present a comparative review of all known Palaeocarpinus species to evaluate morphology and diversity. We recognize a broader North American range for the Paleocene species P. joffrensis, and establish three new species, including two from the Paleocene of Wyoming, P. pterabaratra and P. pteravestigia, and one from the Eocene of Oregon, P. parva. We also update nomenclature for the species previously recognized from the Paleocene of France. Lastly, we discuss the morphological diversity and characteristics of bracts within Palaeocarpinus, and compare the involucres and nuts to those of extant Carpinus and Corylus to, and consider the evolutionary implications. [ABSTRACT FROM AUTHOR]

Our knowledge of the foraminiferal fossil record of Antarctica is notoriously patchy but still offers us an overview of its Cenozoic faunas. Few occurrences have been reported for the continent, with deep-sea assemblages described mainly for its eastern portion. Here we describe 21 taxa of large agglutinated foraminifers from the Miocene Hobbs Glacier Formation and the Plio-Pleistocene Weddell Sea Formation on Seymour Island, West Antarctica, including the gigantic Ammodiscus vastus new species. Most of them consist of genera or species typical of deep-sea agglutinated assemblages. All specimens are completely filled and partially covered by lithified micrite. This, along with the postfill fragmentation of some tests, indicates their re-elaboration from older deposits. Because all of these foraminifers share the same taphonomic features and most of them represent taxa associated with deep-sea settings, they probably represent a flysch-type assemblage from an unknown deposit that was eroded and had its microfossils scattered through post-Paleogene sediments. A Paleocene age for this putative assemblage is indicated by the presence of Reticulophragmiun garcilassoi (Frizzell, 1943), a Paleocene index fossil, and by its association with the Cretaceous–Paleocene Ammodiscus pennyi Cushman and Jarvis, 1928. If taken as a coherent foraminiferal assemblage, it represents one of the few deep-sea assemblages known for West Antarctica, and the first flysch-type assemblage recognized for the Antarctic Cenozoic. In addition, it would show that the Paleocene foraminiferal communities of the West Antarctica's deep-sea floor were more like their Pacific counterparts than their Atlantic equivalents. UUID: http://zoobank.org/0d281489-c0c6-47b4-9884-f820806485b7 [ABSTRACT FROM AUTHOR]

Summary: Cunoniaceae are important elements of rainforests across the Southern Hemisphere. Many of these flowering plants are considered Paleo‐Antarctic Rainforest Lineages that had a Gondwanan distribution since the Paleocene. Fossils of several modern genera within the family, such as Ceratopetalum, have indicated biogeographical connections between South America and Australia in the Cenozoic.Here, we report a dramatic geographical range extension for Ceratopetalum, and Cunoniaceae as a whole, based on two exceptionally preserved fossil winged fruits from Campanian (c. 82–80 Ma old) deposits on Sucia Island, Washington, USA. The fossils were studied using physical sectioning, light microscopy, micro‐computed tomography scanning and multiple phylogenetic analyses.The fossil fruits share diagnostic characters with Ceratopetalum such as the presence of four to five persistent calyx lobes, a prominent nectary disk, persistent stamens, a semi‐inferior ovary and two persistent styles. Based on morphological comparisons with fruits of extant species and support from phylogenetic analyses, the fossils are assigned to a new species Ceratopetalum suciensis.These fossils are the first unequivocal evidence of crown Cunoniaceae from the Cretaceous of North America, indicating a more complicated biogeographical history for this important Gondwanan family. [ABSTRACT FROM AUTHOR]

Mammals are the most encephalized vertebrates, with the largest brains relative to body size. Placental mammals have particularly enlarged brains, with expanded neocortices for sensory integration, the origins of which are unclear. We used computed tomography scans of newly discovered Paleocene fossils to show that contrary to the convention that mammal brains have steadily enlarged over time, early placentals initially decreased their relative brain sizes because body mass increased at a faster rate. Later in the Eocene, multiple crown lineages independently acquired highly encephalized brains through marked growth in sensory regions. We argue that the placental radiation initially emphasized increases in body size as extinction survivors filled vacant niches. Brains eventually became larger as ecosystems saturated and competition intensified. [ABSTRACT FROM AUTHOR]

Premise of research. Our concept of the former diversity and geographic spread of Platanaceae continues to expand. Unlobed platanaceous leaves have been poorly known in the fossil record of western North America. New information on the extinct Paleogene genus Platimeliphyllum and its associated reproductive structures is helping to unravel the biogeographic and evolutionary history of Platanaceae. Methodology. We studied leaves of Platimeliphyllum and associated platanaceous inflorescences and infructescences from the Eocene of western North America and northeastern China. Epidermal anatomy was obtained from cuticle fragments macerated in Schultze solution and studied using transmitted light and epifluorescence microscopy. In situ pollen from inflorescences was studied using light microscopy and SEM. Pivotal results. We provide new evidence supporting the platanaceous affinity of Platimeliphyllum and document its occurrence in the Eocene of western North America as well as in eastern Asia. We present the new combinations Platimeliphyllum durhamensis (Wolfe) comb. nov. from Washington and Oregon and Platimeliphyllum fushunensis (Chen) comb. nov. from Fushun, Liaoning Province, northeastern China. This extends the geographic range of a genus previously known mainly from the Paleocene and Eocene of Russia and Kazakhstan. The ovate, unlobed, simple laminae correspond to Platanaceae in their marginal teeth with rounded sinuses, straight secondary veins, agrophic veins, and orthogonal tertiary and quaternary venation. The association of these leaves with platanaceous inflorescences further confirms their affinities with Platanaceae. Conclusions. Platimeliphyllum likely spread between North America and Asia via the Bering Land Bridge in the Paleocene or Eocene. Previous climate estimates of the Fushun flora based on the coexistence approach need reevaluation with the updated taxonomy of the flora. The co-occurrence of Platimeliphyllum with Macginitiea , Platanites , and Platanus indicates that an array of platanaceous lineages coexisted during the Eocene in western North America. [ABSTRACT FROM AUTHOR]

Among dinoflagellates, extant cladopyxidaceans may provide a missing link to better understand the first evolutionary transformations from ancestral configurations toward the more abundant and more derived patterns in Gonyaulacales and Peridiniales. A restudy of the extant, motile-defined Micracanthodinium setiferum using plankton samples from the Indian and Atlantic oceans and the Mediterranean Sea demonstrates that the correct plate formula is Po, Pt, X, 3′ + *4′, 4a, 7′′, 7C, 4S, ?6′′′, 0p, 2′′′′. A ventral pore is found between 1′, 3′ and *4′. A restudy of the extinct, fossil-defined Cladopyxidium saeptum from the upper Paleocene of Delaware (USA), demonstrated the presence of an identical tabulation. A ventral pore (= porichnion) was positioned between *1′ and 7′′. Cladopyxidium is morphologically closer to Micracanthodinium than to Cladopyxis. Since Cladopyxidium has been extinct since the middle Eocene, it is unlikely that Micracanthodinium and Cladopyxidium have a direct biological link; the close morphological similarity between them does, however, suggest an important phylogenetic relationship between them in the evolution of cladopyxidaceans. [ABSTRACT FROM AUTHOR]

Premise: Nearly 200 araceous leaves and two spadices have been identified among Paleocene fossils from the Blindman River locality near Blackfalds, Alberta, Canada. Although not found in attachment, these probably represent parts of the same extinct plant species. Methods: Specimens were studied using light microscopy. Phylogenetic analyses using a morphological matrix of living and fossil Araceae were performed using TNT version 1.5 to help establish relationships of the fossil leaves and spadices within Araceae and to each other. Results: Leaves are simple with a broad petiole, entire margin, and elliptic to ovate or oblong blade with an acute to slightly rounded apex. A multi‐veined midrib extends into the basal region of the blade. Parallelodromous primary veins of two orders diverge at acute angles, converging with a submarginal vein or at the apex. Transverse veins are opposite percurrent, producing rectangular to polygonal areoles. Higher‐order veins are mixed opposite/alternate. Spadices are cylindrical, with helically arranged, bisexual, perigoniate flowers, each with six free tepals and a protruding style. Fruits are trilocular, with axile placentation and one seed per locule. Conclusions: Leaves are assignable to the fossil genus Orontiophyllum J. Kvaček & S.Y. Sm. as O. grandifolium comb. nov. Spadices are described as Bognerospadix speirsiae gen. et sp. nov. Leaves and spadices each conform to an early‐diverging lineage of Araceae, increasing the known diversity of Proto‐Araceae (viz., subfamilies Gymnostachydoideae and Orontioideae). Together, they provide strong evidence for extinct Proto‐Araceae with novel combinations of characters shortly after the Cretaceous‐Paleogene floral transition. [ABSTRACT FROM AUTHOR]

The first fossil otolith association from the middle Paleocene (Selandian) of Scania, southern Sweden is described. Forty-seven otoliths were retrieved from shallow wells representing 14 teleost taxa. Many specimens are small and/or eroded and, therefore, not identifiable to species level. Nevertheless, our findings indicate the potential for further fossil otolith discoveries in the region. The Scanian otolith-based fauna greatly resembles the better-known coeval association from Copenhagen, Denmark, but is relatively rich and diverse in perciform otoliths. The fauna records the first occurrence of Serranus? caribbaeus from the European Paleocene, and of Archaemacruroides ornatus from the Selandian of the North Sea Basin. [ABSTRACT FROM AUTHOR]

Premise of research. Melastomataceae are a diverse and primarily tropical family with a particularly sparse fossil record. Various biogeographic interpretations based on phylogenies, extant distribution, and a limited fossil record have placed the origin of the family in either Laurasia or Gondwana (eastern or western). Methodology. We describe Xystonia simonae M. Carvalho gen. et sp. nov. on the basis of fossil leaves from middle–late Paleocene deposits of the Bogotá Formation in central Colombia. These leaves have a characteristic acrodromous venation pattern common among subfamily Melastomatoideae. The leaves are compared with various acrodromously veined fossils and living angiosperms to assess their natural affinities. Pivotal results. The fossil leaves described predate the earliest known occurrence of Melastomatoideae by 5–7 Myr and conflict with previous interpretations that considered Melastomatoideae as Laurasian in origin. In revising the fossil record of Melastomataceae, we reevaluated the age of Melastomaephyllum danielis Huert. to be Miocene (previously Eocene/Oligocene) using pollen obtained from the rock that contained the type specimen. Conclusions. Our findings contribute to the scant early records of Melastomataceae and show that Melastomatoideae was part of a tropical rain forest assemblage by the middle–late Paleocene. Leaf galls and other leaf damage on X. simonae evidence intense and specialized biotic interactions in the early evolution of this lineage. [ABSTRACT FROM AUTHOR]

The known fossil record of crocodyliforms in Europe during the Paleogene is significantly biased, in that the fauna of Western Europe is far better sampled and understood compared to that of Eastern Europe. We describe in detail all known crocodyliform remains from the middle Eocene (Lutetian) Ikovo locality in Ukraine. We conclude that at least two taxa were present: a moderate to large-sized Tomistominae indet. similar to the basalmost known tomistomines, and the small-sized basal alligatoroid cf. Diplocynodon sp. Despite its scarcity, this is the first basal alligatoroid material reported from Eastern Europe (as part of post-Soviet countries) and the easternmost record of diplocynodontines in Europe so far. An allegedly freshwater cf. Diplocynodon sp. contributes a rare faunal element to the vertebrate assemblage of the Ikovo locality, otherwise dominated by resident or facultative marine taxa. The fossil record and historical paleobiogeography of crocodyliforms from the Paleocene and Eocene of Europe are reviewed. As it has been already known, the middle Eocene fauna of crocodyliforms proves to be taxonomically diverse and complex. Its constituent lineages geographically originated in Asia or North America (Diplocynodontinae, Asiatosuchus -like crocodyloids, Planocraniidae), North America (derived alligatorines), Africa (Tomistominae), and Gondwana (ziphodont mesoeucrocodylians Iberosuchus and Bergisuchus), with possible subsequent speciation in Europe. We propose a novel hypothesis of Asian origins of European diplocynodontines, which will be explicitly tested in future studies. The revealed similarities between crocodylians and turtles from the Ikovo locality and those from Western Europe support the presence of a single Pan-European biogeographical zone during the middle Eocene, distinct from that of Asia. [ABSTRACT FROM AUTHOR]

The ichnofossil Lepidenteron provides a unique taphonomic window into the life habits of a tube-dwelling predator, probably an eunicid polychaete, and its fish prey. Here we describe a new tube-like ichnofossil Lepidenteron mortenseni n. isp. from the Kerteminde Marl (100-150 m palaeo-water depth) from the Gundstrup gravel pit near Odense, Fyn, Denmark. 110 individual tubes were examined which contain fish remains, including a variety of disarticulated bones and otoliths, by far dominated by a single gadiform taxon referred herein to as Bobbitichthys n. gen. The isolated otoliths here associated with disarticulated gadiform bones have previously been described, from the time equivalent Lellinge Greensand exposed in the Copenhagen area, as Hymenocephalus rosenkrantzi, a grenadier fish (family Macrouridae). The abundance of associated bones and otoliths in the examined tubes allowed us to reconstruct part of the cranial configuration of Bobbitichthys rosenkrantzi and to tentatively interpret it as a stem macrourid. Bobbitichthys rosenkrantzi represents the earliest grenadier known in the fossil record. Additional, although considerably less abundant, skeletal remains and otoliths have been tentatively referred to a long-fin bonefish (family Pterothrissidae, Pterothrissus? conchaeformis), a viviparous brotula (family Bythitidae, Bidenichthys? lapierrei), a conger eel (family Congridae, possibly belonging to Rhynchoconger angulosus), and another unidentified gadiform. [ABSTRACT FROM AUTHOR]

Phytocreneae (Icacinaceae) are a tribe of climbing plants distributed throughout tropical Afro-Eurasia and Papua New Guinea. There is a rich Cenozoic fossil record of the group with occurrences on all continents except Antarctica. Fossil evidence supports a Cretaceous origin but the biogeographic history of Phytocreneae remains unclear. We examined a silicified endocarp collected from the Danian (early Paleocene) Salamanca Formation at the Estancia Las Violetas locality. We investigated the internal structure using micro-CT scanning and compared the fossil with fruits of other living and fossil species. Finally, we explored the biogeographic history of the tribe graphically and discuss the implications of this discovery. The endocarp belongs to the fossil genus Palaeophytocrene. This new occurrence significantly expands the known geographic range of Phytocreneae in South America. Furthermore, this is the oldest (ca. 63 Ma) unequivocal evidence of the tribe in the southern hemisphere. The presence of Phytocreneae at Estancia Las Violetas confirms that these lianas occurred in mid-latitude forests by the early Paleocene, and it also reveals that the tribe likely survived the end-Cretaceous extinction event in southern South America. Future work on the tribe should include filling gaps in the Gondwanan record to test the hypothesis that Australasian lineages are related to American lineages via high-latitude dispersal. • A new species of Phytocreneae (Icacinaceae) is described from a fossil fruit. • The fossil was collected from the Paleocene Salamanca Formation, Patagonia, Argentina. • The discovery expands the known range of fossil Phytocreneae in South America. • This is the oldest unequivocal evidence of Phytocreneae in the Southern Hemisphere. • Southern-hemisphere occurrences support a high-latitude connection with Australia during the Paleogene. [ABSTRACT FROM AUTHOR]

The osteoderms are the building blocks that construct the shields of cingulates. They have been found in the fossil record since the Paleocene and often their surface sculptures permit identification at the species level, although variations are observed among the shields. In this study, we describe the exceptional preservation of a delicate shield on the foot of Eutatus seguini Gervais 1867 (Late Pleistocene). The osteoderms in this region are characterized by their thinness, roughness, and lack of a well-defined ornamental pattern. They feature a rounded anterior border, fine foramina on their exposed surface, and thin hairy foramina on the anterolateral border. This specimen demonstrates that E. seguini also had a foot shield like extant armadillos, although its phylogenetic position within the cingulates is still unresolved. • A preserved in situ osteoderm shield is described on the foot of E. seguini. • Foot shield osteoderms differ from dorsal shield's in thickness and ornamentation. • Eutatus seguini had an osteoderm foot shield like extant cingulates. [ABSTRACT FROM AUTHOR]

Southern-Hemisphere terrestrial communities from the early Paleocene are poorly known, but recent work on Danian plant fossils from the Salamanca Formation in Chubut Province, Argentina are providing critical data on earliest Paleocene floras. The fossils described here come from a site in the Salamanca Formation dating to ca. 1 million years or less after the end-Cretaceous extinction event; they are the first fossil flowers reported from the Danian of South America, and possible the entire Southern Hemisphere. They are compressions and impressions in flat-laminated light gray shale, and they belong to the family Rhamnaceae (buckthorns). Flowers of Notiantha grandensis gen. et sp. nov. are pentamerous, with distinctly keeled calyx lobes projecting from the hypanthium, clawed and cucullate emarginate petals, antepetalous stamens, and a pentagonal floral disk that fills the hypanthium. Their phylogenetic position was evaluated using a molecular scaffold approach combined with morphological data. Results indicate that the flowers are most like those of extant ziziphoid Rhamnaceae. The associated leaves, assigned to Suessenia grandensis gen. et sp. nov. are simple and ovate, with serrate margins and three acrodromous basal veins. They conform to the distinctive leaves of some extant Rhamnaceae in the ziziphoid and ampelozizyphoid clades. These fossils provide the first unequivocal megafossil evidence of Rhamnaceae in the Southern Hemisphere, demonstrating that Rhamnaceae expanded beyond the tropics by the earliest Paleocene. Given previous reports of rhamnaceous pollen in the late Paleogene and Neogene of Antarctica and southern Australia, this new occurrence increases the possibility of high-latitude dispersal of this family between South America and Australia via Antarctica during the Cenozoic. [ABSTRACT FROM AUTHOR]

[Display omitted] • Most taxonomically comprehensive phylogeny for Charadriiformes to date. • Shorebirds originated in the Paleocene, earlier than indicated by recent studies. • Rapid radiations detected for select gull genera and Old World oystercatchers. • Plover monophyly and the exact position of the ibisbill remain unresolved. Shorebirds (Charadriiformes) are a globally distributed clade of modern birds and, due to their ecological and morphological disparity, a frequent subject of comparative studies. While molecular phylogenies have been key to establishing the suprafamilial backbone of the charadriiform tree, a number of relationships at both deep and shallow taxonomic levels remain poorly resolved. The timescale of shorebird evolution also remains uncertain as a result of extensive disagreements among the published divergence dating studies, stemming largely from different choices of fossil calibrations. Here, we present the most comprehensive non-supertree phylogeny of shorebirds to date, based on a total-evidence dataset comprising 353 ingroup taxa (90% of all extant or recently extinct species), 27 loci (15 mitochondrial and 12 nuclear), and 69 morphological characters. We further clarify the timeline of charadriiform evolution by time-scaling this phylogeny using a set of 14 up-to-date and thoroughly vetted fossil calibrations. In addition, we assemble a taxonomically restricted 100-locus dataset specifically designed to resolve outstanding problems in higher-level charadriiform phylogeny. In terms of tree topology, our results are largely congruent with previous studies but indicate that some of the conflicts among earlier analyses reflect a genuine signal of pervasive gene tree discordance. Monophyly of the plovers (Charadriidae), the position of the ibisbill (Ibidorhyncha), and the relationships among the five subfamilies of the gulls (Laridae) could not be resolved even with greatly increased locus and taxon sampling. Moreover, several localized regions of uncertainty persist in shallower parts of the tree, including the interrelationships of the true auks (Alcinae) and anarhynchine plovers. Our node-dating and macroevolutionary rate analyses find support for a Paleocene origin of crown-group shorebirds, as well as exceptionally rapid recent radiations of Old World oystercatchers (Haematopodidae) and select genera of gulls. Our study underscores the challenges involved in estimating a comprehensively sampled and carefully calibrated time tree for a diverse avian clade, and highlights areas in need of further research. [ABSTRACT FROM AUTHOR]

Deviacer guangxiensis Chen & Manchester sp. nov. is described based on asymmetric samaras from the Oligocene Ningming Formation in Guangxi, South China, representing the first documentation of Deviacer fossils in Asia. The Oligocene species, with relatively large fruits, represents the youngest record of the genus so far known; all other records are from the Paleocene and Eocene, or late Eocene—early Oligocene in western North America and Europe. It indicates that the extinct genus, Deviacer, was widely distributed in the northern hemisphere during the Paleogene. [ABSTRACT FROM AUTHOR]

Recent studies show Xenarthra to be even more isolated systematically from other placental mammals than traditionally thought. The group not only represents 1 of 4 primary placental clades, but proposed links to other fossorial mammal taxa (e.g., Pholidota, Palaeanodonta) have been contradicted. No unambiguous Paleocene fossil xenarthran remains are known, and Eocene remains consist almost exclusively of isolated cingulate osteoderms and isolated postcrania of uncertain systematic provenance. Cingulate skulls are unknown until the late middle Eocene, and the oldest sloth and anteater skulls are early Oligocene and early Miocene age, respectively; there are no nearly complete xenarthran skeletons until the early Miocene. Ecological reconstructions of early xenarthrans based on extant species and the paleobiology of extinct Neogene taxa suggest the group's progenitors were myrmecophagous with digging and perhaps some climbing adaptations. The earliest cingulates were terrestrial diggers and likely myrmecophagous but soon diverged into numerous omnivorous lineages. Early sloths were herbivores with a preference for forested habitats, exhibiting both digging and climbing adaptations. We attribute the rarity of early xenarthran remains to low population densities associated with myrmecophagy, lack of durable, enamel-covered teeth, and general scarcity of fossil localities from tropical latitudes of South America. The derivation of numerous omnivorous and herbivorous lineages from a myrmecophagous ancestor is a curious and unique feature of xenarthran history and may be due to the peculiar ecology of the native South American mammal fauna. Further progress in understanding early xenarthran evolution may depend on locating new Paleogene fossil sites in northern South America. [ABSTRACT FROM AUTHOR]

Background: It is conventionally accepted that the lepidopteran fossil record is significantly incomplete when compared to the fossil records of other, very diverse, extant insect orders. Such an assumption, however, has been based on cumulative diversity data rather than using alternative statistical approaches from actual specimen counts. Results: We reviewed documented specimens of the lepidopteran fossil record, currently consisting of 4,593 known specimens that are comprised of 4,262 body fossils and 331 trace fossils. The temporal distribution of the lepidopteran fossil record shows significant bias towards the late Paleocene to middle Eocene time interval. Lepidopteran fossils also record major shifts in preservational style and number of represented localities at the Mesozoic stage and Cenozoic epoch level of temporal resolution. Only 985 of the total known fossil specimens (21.4%) were assigned to 23 of the 40 extant lepidopteran superfamilies. Absolute numbers and proportions of preservation types for identified fossils varied significantly across superfamilies. The secular increase of lepidopteran family-level diversity through geologic time significantly deviates from the general pattern of other hyperdiverse, ordinal-level lineages. Conclusion: Our statistical analyses of the lepidopteran fossil record show extreme biases in preservation type, age, and taxonomic composition. We highlight the scarcity of identified lepidopteran fossils and provide a correspondence between the latest lepidopteran divergence-time estimates and relevant fossil occurrences at the superfamily level. These findings provide caution in interpreting the lepidopteran fossil record through the modeling of evolutionary diversification and in determination of divergence time estimates. [ABSTRACT FROM AUTHOR]

Extant Neotropical rainforests are well known for their remarkable diversity of fruit and seed types. Biotic agents disperse most of these disseminules, whereas wind dispersal is less common. Although wind-dispersed fruits and seeds are greatly overshadowed in closed rainforests, many important families in the Neotropics (e.g., Bignoniaceae, Fabaceae, Malvaceae, Orchidaceae, Sapindaceae) show numerous morphological adaptations for anemochory (i.e. wings, accessory hairs). Most of these living groups have high to moderate levels of plant diversity in the upper levels of the canopy. Little is known about the fossil record of wind-dispersed fruits and seeds in the Neotropics. Six new species of disseminules with varied adaptations for wind dispersal are documented here. These fossils, representing extinct genera of Ulmaceae, Malvaceae, and some uncertain families, indicate that wind-dispersed fruit and seed syndromes were already common in the Neotropics by the Paleocene, coinciding with the early development of multistratal rainforests. Although the major families known to include most of the wind-dispersed disseminules in extant rainforests are still missing from the Paleogene fossil record of South and Central America, the new fossils imply that anemochory was a relatively important product and/or mechanism of plant evolution and diversification in early Neotropical rainforests. [ABSTRACT FROM AUTHOR]

Plant and associated insect-damage diversity in the western U.S.A. decreased significantly at the Cretaceous-Paleogene (K-Pg) boundary and remained low until the late Paleocene. However, the Mexican Hat locality (ca. 65 Ma) in southeastern Montana, with a typical, low-diversity flora, uniquely exhibits high damage diversity on nearly all its host plants, when compared to all known local and regional early Paleocene sites. The same plant species show minimal damage elsewhere during the early Paleocene. We asked whether the high insect damage diversity at Mexican Hat was more likely related to the survival of Cretaceous insects from refugia or to an influx of novel Paleocene taxa. We compared damage on 1073 leaf fossils from Mexican Hat to over 9000 terminal Cretaceous leaf fossils from the Hell Creek Formation of nearby southwestern North Dakota and to over 9000 Paleocene leaf fossils from the Fort Union Formation in North Dakota, Montana, and Wyoming. We described the entire insect-feeding ichnofauna at Mexican Hat and focused our analysis on leaf mines because they are typically host-specialized and preserve a number of diagnostic morphological characters. Nine mine damage types attributable to three of the four orders of leaf-mining insects are found at Mexican Hat, six of them so far unique to the site. We found no evidence linking any of the diverse Hell Creek mines with those found at Mexican Hat, nor for the survival of any Cretaceous leaf miners over the K-Pg boundary regionally, even on well-sampled, surviving plant families. Overall, our results strongly relate the high damage diversity on the depauperate Mexican Hat flora to an influx of novel insect herbivores during the early Paleocene, possibly caused by a transient warming event and range expansion, and indicate drastic extinction rather than survivorship of Cretaceous insect taxa from refugia. [ABSTRACT FROM AUTHOR]

Since its first description in 1960, the brachyuran crab genus Pleolobites was restricted to the Eocene (Ypresian) strata of Ivory Coast. Here, we report newly collected specimens that indicate its presence in the Paleocene (Thanetian) of Togo. This monotypic genus has been classified within various higher taxa, including Portunidae, Macropipidae, and Carcinidae, depending on the concurrent classification of portunoid crabs. Through the re-examination of the type material of Pleolobites erinaceus , the most recent assignment of Pleolobites within the subfamily Polybiinae of the family Carcinidae is disputed herein. Nevertheless, we refrain from assigning Pleolobites to any family and opine for its placement as Portunoidea incertae sedis. Additionally, the crab genus Rhachiosoma , morphologically similar to Pleolobites , is also removed from Polybiinae and placed in Portunoidea incertae sedis. It is further argued that Palaeoxanthopsis , Paraverrucoides , Parazanthopsis , and Verrucoides currently classified within the family Palaeoxanthopsidae of the superfamily Carpilioidea show striking similarities with Pleolobites and Rhachiosoma , including the morphology of dorsal carapace, thoracic sternum and pleon. Additionally, chelipeds with a spiny propodal margin and multi-lobed serial finger-teeth, otherwise characteristic for Portunoidea are found in Parazanthopsis and Palaeoxanthopsis. It remains to be investigated whether these resemblances are the result of evolutionary convergence or close phylogenetic relationships. add a blank line [ABSTRACT FROM AUTHOR]

Calissounemys matheroni gen. et sp. nov. (Testudines) is described on the basis of a skull and shell elements from the Upper Cretaceous of Var, southern France. This new taxon is assigned to the family Compsemydidae and characterized by a thick-boned, robust skull, a shallow temporal emargination, a crista supraoccipitalis not extending beyond the posterior edge of the skull roof, large nasals meeting along the midline for their full length; frontals retracted from the orbital margin, absence of a cheek emargination, a large jugal forming a substantial part of the orbital margin, absence of a secondary palate and an uneven upper triturating surface; and the shell with vertebral 1 clearly wider than vertebrals 2-3, with the lateral margins strongly divergent towards the anterior border and wider than long vertebrals 2-3. This find increases the diversity of the Late Cretaceous turtle fauna from southern France, and fills a stratigraphical gap in the fossil record of Compsemydidae between the Early Cretaceous and the Paleocene in Europe. [ABSTRACT FROM AUTHOR]

The Chuckanut and Manastash formations were deposited in a lowland fluvial environment in western Washington during the Paleocene–Eocene. We provide a thorough paleotemperature analysis using the physiognomic characteristics from the fossil dicotyledonous leaves from these formations using two techniques, Leaf Margin Analysis (LMA) and Climate Leaf Analysis Multivariate Program (CLAMP). This work differs from previous analyses by 1) analyzing more localities and including the assessment of the never-before described Taneum Ridge Body and Manastash Main Body within the Manastash Formation and the Maple Falls Member of the Chuckanut Formation, and 2) using two different techniques to decipher mean annual temperatures through time. In this study, mean annual temperatures (MAT) were determined from 125 distinct morphotypes and are several degrees higher at each locality than previously reported. MAT values derived from LMA ranged from 17.0° to 28.8°C for the lowermost and 13.4° to 19.5°C for the uppermost Chuckanut Formation. The Manastash Formation had MATs ranging from 17.1°C to 29.1°C. Using CLAMP, paleotemperatures ranged from 15.3° to 19.4°C for the lowermost and 12.3° to 15.6°C for the uppermost Chuckanut Formation and 15.8 to 21.3°C for the Manastash Formation. These data are compared to other Eocene–Paleocene formations in the western US; the Chuckanut and Manastash formations record some of the warmest paleotemperatures in the Paleogene in the western US because of their low-elevation locations. These paleotemperatures may reflect the terrestrial signal of paleoclimate optima defined in marine rocks during the Paleocene–Eocene. [ABSTRACT FROM AUTHOR]

We compiled the fossil record of the heterosporous water ferns (Salviniales) including macro- and microfossils from South America and the Antarctic Peninsula. Both extant families, Marsileaceae and Salviniaceae, are well represented and several fossil spore genera that cannot be placed within the extant families are included as Incertae sedis. Marsileaceae is first recorded in the Middle to Late Jurassic. Incertae sedis genera are recorded for first time in the Early Cretaceous while Salviniaceae in the Late Cretaceous. Two diversity spikes are recognized: one spanned the Aptian–Albian (Early Cretaceous) and is linked to an increase in species diversity within Marsileaceae; and the other occurred during the Campanian–Maastrichtian (Late Cretaceous) and it is associated with the diversification at generic level of the entire Salviniales. Two decreases in diversity are recognized: one during the Cenomanian–Santonian and affected Marsileaceae at specific level but not its generic diversity, and the second is related to the Cretaceous–Paleogene mass extinction and affected all Salviniales at generic and specific levels. From the Paleocene onwards there is a steady decline in the fossil record of the group, with most remains belonging to the extant genera. This study suggests that Southern Hemisphere aquatic ferns underwent a sharp radiation during the Late Cretaceous and a deep decline in the Paleocene that parallels that occurred in the Northern Hemisphere. Probably, the temporal co-occurrence of geological and climate events and the availability of suitable lineages promoted the evolutionary changes of the water ferns in the studied area, including the high diversification and distribution in the Cretaceous and the subsequent post-Maastrichtian decline. • Compilation of Salviniales fossil record from South America and Antarctic Peninsula. • Diversification of Marsileaceae species during the Early Cretaceous. • Diversification of Salviniales during the Late Cretaceous. • K–Pg extinction and mainly modern genera from the Paleocene onwards. • Salviniales evolutionary history in relation to paleogeography and paleoenvironments. [ABSTRACT FROM AUTHOR]

Fabaceae are one of the most diverse flowering-plant groups today, and in Mexico their presence is well represented since the late Cretaceous. In this work are reported two fossil woods from the El Bosque Formation, early Eocene of Southern Mexico. These new records show close resemblance with the modern wood of Kingiodendron (Detarioideae) and Enterolobium (Caesalpinioideae). Detarioideae subfamily show a diversity much higher in tropical Africa than in South America or Asia, while the mimosoid clade diversity is pantropical. The relicts of both groups are known from the Paleocene onwards around the world. Comparing the fossil record and the fossils here studied, it is possible to confirm the presence of Fabaceae in Mexican territory since the Cretaceous and to suggest that the family was one of the most important components of the earliest forests in Mexico through the Cenozoic. Additionally, in this work describes the oldest record of the genera fossil for Kingiodendron and Enterolobium worldwide, which contributes towards the understanding the paleo-dispersal pathways of both groups within the early branching Fabaceae. • Fabaceae is one of the most important groups of plants in the extant vegetation in Mexico. • We describe the oldest records of the genera Kingiodendron and Enterolobium worldwide. • These fossil woods reflect the floristic legume diversity seen in the Mexican Eocene. • Fabaceae was one of the most important components of the earliest forests in Mexico through the Cenozoic. [ABSTRACT FROM AUTHOR]

Micrometer-sized spherical and rod-shaped forms have been reported in many phosphorites and often interpreted as microbes fossilized by apatite, based on their morphologic resemblance with modern bacteria inferred by scanning electron microscopy ( SEM) observations. This interpretation supports models involving bacteria in the formation of phosphorites. Here, we studied a phosphatic coprolite of Paleocene age originating from the Ouled Abdoun phosphate basin ( Morocco) down to the nanometer-scale using focused ion beam milling, transmission electron microscopy ( TEM), and scanning transmission x-ray microscopy ( STXM) coupled with x-ray absorption near-edge structure spectroscopy ( XANES). The coprolite, exclusively composed of francolite (a carbonate-fluroapatite), is formed by the accumulation of spherical objects, delimited by a thin envelope, and whose apparent diameters are between 0.5 and 3 μm. The envelope of the spheres is composed of a continuous crown dense to electrons, which measures 20-40 nm in thickness. It is surrounded by two thinner layers that are more porous and transparent to electrons and enriched in organic carbon. The observed spherical objects are very similar with bacteria encrusting in hydroxyapatite as observed in laboratory experiments. We suggest that they are Gram-negative bacteria fossilized by francolite, the precipitation of which started within the periplasm of the cells. We discuss the role of bacteria in the fossilization mechanism and propose that they could have played an active role in the formation of francolite. This study shows that ancient phosphorites can contain fossil biological subcellular structures as fine as a bacterial periplasm. Moreover, we demonstrate that while morphological information provided by SEM analyses is valuable, the use of additional nanoscale analyses is a powerful approach to help inferring the biogenicity of biomorphs found in phosphorites. A more systematic use of this approach could considerably improve our knowledge and understanding of the microfossils present in the geological record. [ABSTRACT FROM AUTHOR]

Abstract: Boxfishes (superfamily Ostracioidea, order Tetraodontiformes) are comprised of 37 species within the families Aracanidae (13 sp.) and Ostracidae (24 sp.). These species are characterized by several dramatic reductive trends in their axial and appendicular skeleton, and by the presence of a carapace formed by enlarged and thickened scale plates. While strong support exists for the monophyly of both families, interspecific relationships remain unclear as no species-level molecular phylogeny currently exists for either of these two clades, and the only hypotheses of relationships are based on morphological studies that were mostly restricted to generic-level relationships. Here we present the results of a new phylogenetic study of a dataset composed of 9 loci for 26 species of boxfishes using both likelihood and Bayesian methods. Our topology strongly supports the monophyly of both groups, and additionally provides strongly supported resolution for the vast majority of species-level interrelationships. Based on this new phylogeny, we suggest changing the taxonomic status of the species Lactoria fornasini to Tetrasomus fornasini, and Rhynchostracion nasus to Ostracion nasus. Using a Bayesian approach to divergence time estimation we inferred a Paleocene origin of the Ostracioidea, with an estimated origin of the reef-associated ostraciids spanning the Eocene and Oligocene, and a Miocene/Pliocene origin of the aracanids. [Copyright &y& Elsevier]

Abstract: Environmental fluctuations are a driving force in vertebrate evolution, but cryptobranchids (giant salamanders) show little morphologic change since the Jurassic. Here we analyze their fossil distribution in the Cenozoic of Eurasia and show that morphologic stasis is also maintained by stable environments, making giant salamanders an ideal proxy-group for environmental and palaeoclimatic studies. The climate space of recent and fossil cryptobranchids is best characterized by high humidity with mean annual precipitation values over 900mm. The recorded patchiness of their fossil record can be explained by habitat tracking and/or range expansion from higher altitudes into lowland settings during humid periods with increased basinal relief. In Central Asia cryptobranchids are recorded from five intervals, four of them are global warm periods: Paleocene–Eocene Thermal Maximum, Late Oligocene warming, Miocene Climate Optimum, and Mio-Pliocene transition. This distribution suggests that during global warmth the Asian cold high pressure zone during winter months may be weak or absent, thus moist westerly winds penetrate far into the continent. The presence of cryptobranchids also indicates that the aridification across the Eocene–Oligocene boundary as reported from Mongolia and northwestern China, does not occur in the Zaysan Basin, probably due to increased upslope precipitation in the rising Altai Mountains. [Copyright &y& Elsevier]

Abstract: Distinct magnetic properties of marine sediments that record the Palaeocene–Eocene thermal maximum (PETM) have been suggested to be due to a bacterial magnetofossil signal that is linked to enhanced weathering conditions during the PETM. We document the dominance of bacterial magnetite in deep-sea sediments from southern Kerguelen Plateau (Ocean Drilling Program Hole 738C, southern Ocean) not only during the PETM, but also before and after the thermal event. This occurrence of magnetofossils throughout the PETM indicates that the occurrence of bacterial magnetosomes is not due to a preservation effect. Instead, we suggest that it is due to sustained mild iron-reducing conditions that dissolved the most labile aeolian-derived iron, which favoured continued magnetotactic bacterial activity without being strong enough to dissolve the less reactive magnetite and haematite. Enhanced aeolian haematite abundances at the beginning of the PETM indicate drier conditions on the neighbouring Antarctic continent at those times. Our results provide evidence that iron fertilisation by aeolian dust was the main limiting factor that conditioned proliferation of magnetotactic bacteria in the deep sea at the southern Kerguelen Plateau, with the exception of two short periods of rapidly changing palaeoenvironmental conditions at the onset and termination of the PETM. Increased iron supply from aeolian dust, that enhanced oceanic primary productivity and subsequent delivery of organic carbon to the seafloor, along with mild iron-reducing diagenetic conditions, seem to have been necessary to provide the iron needed for magnetite biomineralization by magnetotactic bacteria to drive their marked increase in abundance in the studied PETM record from southern Kerguelen Plateau. Our analyses of a deep-sea PETM record from Hole 1051B at Blake Nose (Atlantic Ocean) failed to identify magnetofossils despite evidence for the occurrence of magnetite and haematite of probable aeolian origin. Contrasting magnetic properties at these PETM sections indicate that further work is needed to understand the palaeoenvironmental and diagenetic factors whose interactions lead to production and preservation of magnetofossils in deep-sea sediments. [Copyright &y& Elsevier]

This paper provides a synthesis of the long- and short-term response of various marine ecosystems (deep oceans, pelagic, pelitic shelves and carbonate platforms) to the Paleocene-Eocene thermal maximum (PETM) and its broader paleoclimatic and paleoceanographic context. Despite the severity and sudden onset of global warming the PETM is not marked by a mass extinction event. The only major extinction is among bathyal to abyssal calcareous benthic foraminifera, including some calcareous agglutinated taxa. Coexisting non-calcareous deep water agglutinated foraminifera, ostracodes and trace fossils show prominent changes in composition, population structure and biodiversity, but there is no clear evidence of global extinctions. Except for the deep-sea calcareous benthic foraminiferal record, the PETM is best classified as a migration and origination event and was instrumental in kick-starting various short- and long-term evolutionary innovations in marine microfossil lineages. In pelagic and shallow shelf ecosystems, migration and origination during and after the PETM appears to precede extinction in the aftermath of the PETM. The response of most marine invertebrates (mollusks, echinoderms, brachiopods) to paleoclimatic and associated environmental changes (e.g., acidification, deoxygenation) during the PETM is virtually unknown as continuous high-resolution data of these groups spanning the PETM are unexplored and possibly not or hardly preserved. Yet information on these groups is required in order to improve assessments of the value of biotic records to deep-time global warming in the context of current climate change. In contrast, the relatively well-established response of Tethyan reef systems to late Paleocene-early Eocene global warming may provide a potential analog to a - possibly bleak - future of present-day coral reefs. [ABSTRACT FROM AUTHOR]

* Premise of the study: Fossil leaves of Menispermaceae were previously described from the Paleocene of Colombia. Because of strong homoplasy of leaf characters, the fossils could not be placed more specifically within recognized clades, and additional data were needed to specify intrafamilial and paleogeographic relationships during the Paleocene. * Methods: Fossil endocarps of Menispermaceae were collected from the Cerrejó n Formation, the recently discovered Bogotá flora, and Wyoming (~60 Ma). We surveyed the endocarp morphology of almost all extant genera, conducted character optimization, a molecular scaffold analysis, and critically reviewed the related fossil genera. * Key results: Parallel syndromes of fruit characters have appeared in unrelated clades of the family according to current phylo-genetic reconstructions. However, mapping selected endocarp characters across those clades that contain horseshoe-shaped endocarps facilitates identification and phylogenetic assessment of the fossils. Three fossil species are recognized. One of them belongs to the extant genus Stephania, which today grows only in Africa and Australasia. Palaeoluna gen. nov. is placed within the pantropical clade composed of extant Stephania, Cissampelos, and Cyclea; this morphogenus is also recognized from the Paleocene of Wyoming. Menispina gen. nov. shows similarity with several unrelated clades. * Conclusions: The new fossils from Colombia reveal a complex paleobiogeographic history of the recognized clades within Menispermaceae, suggesting a more active exchange among neotropical, paleotropical, North American, and European paleo-forests than previously recognized. In addition, the new fossils indicate that neotropical forests were an important biome for the radiation and dispersal of derived lineages in Menispermaceae after the Cretaceous--Paleogene boundary. [ABSTRACT FROM AUTHOR]