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Anagalids are an extinct group of primitive mammals from the Asian Palaeogene thought to be possible basal members of Glires. Anagalid material is rare, with only a handful of crania known. Here we describe the first virtual endocast of an anagalid, based on the holotype of Anagale gobiensis (AMNH 26079; late Eocene, China), which allows for comparison with published endocasts from fossil members of modern euarchontogliran lineages (i.e. primates, rodents, lagomorphs). The endocast displays traits often observed in fossorial mammals, such as relatively small petrosal lobules and a low neocortical ratio, which would be consistent with previous inferences about use of subterranean food sources based on heavy dental wear. In fact, Anagale gobiensis has the lowest neocortical ratio yet recorded for a euarchontogliran. This species was olfaction‐driven, based on the relatively large olfactory bulbs and laterally expansive palaeocortex. The endocast supports previous inferences that relatively large olfactory bulbs, partial midbrain exposure and low encephalization quotient are ancestral for Euarchontoglires, although the likely fossorial adaptations of Anagale gobiensis may also partly explain these traits. While Anagale gobiensis is a primitive mammal in many aspects, some of its derived endocranial traits point towards a new, different trajectory of brain evolution within Euarchontoglires. [ABSTRACT FROM AUTHOR]

A proper understanding of the palaeoceanographic evolution of the Drake Passage during the Palaeogene is hampered by the lack of precise tools to date and correlate the sedimentary units of areas adjacent to the region. In this work, considering recently published radiometric U–Pb dates, we revised the age of a previous dinoflagellate zones for the middle to upper Eocene units of the Austral–Magallanes Basin. The quantitative analysis of middle to late Eocene dinoflagellate cyst assemblages from different localities close to the Drake Passage allowed us to reconstruct the palaeoenvironmental conditions and the possible surface ocean currents during this time in the area. Assemblages dated between 41.3 and 38.1 Ma represent relatively warm waters in inner shelf settings, while those ranged between 36 and 35 Ma reflect coastal areas with cool, nutrient‐rich surface waters. The proposed surface ocean circulation pattern, based on dinoflagellate cysts distribution between 41.3 and 38.1 Ma, agrees with the results of a palaeoclimatic numerical model simulation performed with a Drake Passage shallow opening of 100 m depth. At c. 36 Ma, several Antarctic gonyaulacacean taxa tolerant to relatively warmer waters were replaced by some Antarctic peridinacean species better adapted to colder conditions. This change could be linked to a progressive deepening of the Drake Passage that is estimated to have reached 1000 m depth promoting a cooling in the South Atlantic. Such passage depth would have enabled stronger flows from the Pacific to the Atlantic Ocean, which is reflected by the increase of cosmopolitan species. [ABSTRACT FROM AUTHOR]

Collagens are the most abundant proteins in the animal kingdom. They form the structural framework of connective tissues such as bones, tendons and skin, and play important biomechanical role in supporting tissue functions. The preservation of collagen in deep time is a topic of intense debate. Here we provide indisputable evidence for the presence of collagen in early Eocene fish vertebrae using online pyrolysis comprehensive two dimensional gas chromatography time‐of‐flight mass spectrometry (py‐GC×GC‐TOFMS) and immunofluorescence analysis. The presence of cyclic dipeptides such as diketodipyrrole, 2,5‐diketopiperazine of proline‐proline and 2,5‐diketopiperazine of proline‐glycine along with other nitrogen‐bearing molecules in the pyrolysis products of the studied fossils unequivocally demonstrate that collagen can withstand degradation and diagenetic alteration. Immunofluorescence study also confirms the presence of collagen‐I in the fossilized fish vertebrae. Contrary to common opinion, the present findings suggest that the preservation of collagen in fossilized soft tissues is not rare. We propose that one of the essential factors controlling preservation of collagen is the establishment of a suitable microenvironment within the fossil, inhibiting diagenetic alteration including microbial decay. [ABSTRACT FROM AUTHOR]

Cetaceans constitute a textbook example of the secondary adaptation of tetrapods to aquatic life. This major event in the evolutionary history of mammals is often linked in the literature to the limb‐to‐fin transition. Paradoxically, limb bones are scarce in the fossil record of early cetaceans, and the transition from a limb‐adapted morphology for an amphibious life in shallow water to a fin‐adapted morphology for a pelagic lifestyle remains poorly documented. Here, we describe new protocetid remains from the upper Lutetian of Senegal, including a nearly complete articulated forelimb. A cladistic analysis including 24 taxa and 137 morphological characters recovers the new African specimen close to Carolinacetus. It also confirms that cetacean dispersal to the New World was not the result of a single colonization event. A 3D model of the forelimb was reconstructed. Anatomical comparisons suggest that it is unlikely that the Senegalese forelimb was used as a rigid pectoral flipper for steering as in basilosaurids and modern cetaceans. Instead, we suggest that the hand was actively used during swimming. This challenges previous reconstructions of protocetids as mainly foot‐powered swimmers, and suggests that swimming specializations of early cetaceans were probably more diverse than previously considered. [ABSTRACT FROM AUTHOR]

We describe the first endocast reconstruction of a hyaenodont mammal based on X‐ray microtomography. The endocast belongs to the type material of the European hyaenodont Proviverra typica. We performed phylogenetic analysis to contextualize the evolution of endocranial size and complexity in Hyaenodonta. We added several European hyaenodonts and modified several codings of the most recent character–taxon matrix established to question the relationships within Hyaenodonta. Including these new species in a phylogenetic analysis reveals a new clade: Hyaenodontoidea. Comparisons with several previously described endocasts show that there was an increase in complexity in the convolutions of the encephalon within Hyaenodontidae history. Moreover, the analysis of the encephalization quotient reveals that the endocranium of the Hyaenodonta is not smaller than those of fossil Carnivora or some extant Carnivora. Therefore, the extinction of Hyaenodonta may not be linked to the relative size of hyaenodont brains. [ABSTRACT FROM AUTHOR]

A lower jaw of the mesonychian Hapalodectes is reported from Nongshanian sediments (Upper Doumu Formation; middle Paleocene) of the Qianshan Basin (Anhui Province, China). The fragmentary mandible is only the third specimen of Hapalodectidae discovered in Paleocene deposits, and the first in south east China; it is moreover the oldest, the two other specimens having been found in Gashatan (late Paleocene) localities. The premolars and molars of the new fossil are morphologically similar to Hapalodectes dux (late Paleocene of Mongolia), which has been considered to be the most primitive hapalodectid, but their relative proportions recall H. paleocenus and the Eocene Hapalodectes species. As a result, the fossil described herein appears to be different from the other previously described species of Hapalodectes in being morphologically intermediate between H. dux and the other Hapalodectes species, notably the Bumbanian Hapalodectes hetangensis and H. huanghaiensis from China; it is thus identified as a new species, Hapalodectes lopatini (possibly a male individual). Its discovery is important because it sheds light on the initial radiation of hapalodectids. The presence of one primitive hapalodectid in Mongolia previously suggested the Mongolian Plateau as the centre of origination of this carnivorous family, but the discovery of H. lopatini in older sediments from south-east China challenges this hypothesis. In the earliest Eocene, Hapalodectes dispersed from Asia to North America; this event being part of the 'East of Eden' dispersals. This event resulted in the geographical separation of two distinct Hapalodectes groups, in North America and south-eastern China respectively. [ABSTRACT FROM AUTHOR]

The Eocene (Ypresian) fauna of Bolca, Italy yields a famous assemblage of marine tropical teleosts. One of the most anatomically distinctive teleosts from Bolca is the enigmatic † Bajaichthys elegans, generally interpreted as a member of Lampridiformes (oarfishes and their allies). Re-examination of the type and only specimen of † Bajaichthys contradicts this attribution, and we propose that its original description as a member of Zeiformes (dories) was in fact correct. † Bajaichthys bears numerous derived features of zeiforms not found in lampridiforms, including: a pelvic spine, a first vertebra closely associated with the neurocranium, and a reduced metapterygoid not contacting the quadrate. Lampridiform-like attributes, including a greatly elongated ascending process of the premaxilla, are known to be convergent between this group and Zeiformes. Using a combination of morphological and molecular data, we confirm this revised interpretation and resolve the position of † Bajaichthys within zeiform phylogeny. In terms of overall shape, the very elongate † Bajaichthys contrasts with deep-bodied Zeiformes and probably had distinctive ecological habits. Our inferred placement of † Bajaichthys and other fossil taxa with extended caudal peduncles (e.g. † Archaeozeus) suggests that the elongate morphotype is ancestral for Zeiformes as a whole, and that the deep-bodied geometry typical of extant taxa probably appeared several times independently. However, these inferences must be considered preliminary due to low support for patterns of relationships within Zeiformes. The systematic reattribution of † Bajaichthys expands the taxonomic diversity of the Bolca fauna as well as the morphological and ecological diversity of the zeiform clade. [ABSTRACT FROM AUTHOR]

An isolated, yet virtually intact contour feather ( FUM-1980) from the lower Eocene Fur Formation of Denmark was analysed using multiple imaging and molecular techniques, including field emission gun scanning electron microscopy ( FEG- SEM), X-ray absorption spectroscopy and time-of-flight secondary ion mass spectrometry (ToF- SIMS). Additionally, synchrotron radiation X-ray tomographic microscopy ( SRXTM) was employed in order to produce a digital reconstruction of the fossil. Under FEG- SEM, the proximal, plumulaceous part of the feather revealed masses of ovoid microstructures, about 1.7 μm long and 0.5 μm wide. Microbodies in the distal, pennaceous portion were substantially smaller (averaging 0.9 × 0.2 μm), highly elongate, and more densely packed. Generally, the microbodies in both the plumulaceous and pennaceous segments were aligned along the barbs and located within shallow depressions on the exposed surfaces. Biomarkers consistent with animal eumelanins were co-localized with the microstructures, to suggest that they represent remnant eumelanosomes (i.e. eumelanin-housing cellular organelles). Additionally, ToF- SIMS analysis revealed the presence of sulfur-containing organics - potentially indicative of pheomelanins - associated with eumelanin-like compounds. However, since there was no correlation between melanosome morphology and sulfur content, we conclude these molecular structures derive from diagenetically incorporated sulfur rather than pheomelanin. Melanosomes corresponding roughly in both size and morphology with those in the proximal part of FUM-1980 are known from contour feathers of extant parrots (Psittaciformes), an avian clade that has previously been reported from the Fur Formation. [ABSTRACT FROM AUTHOR]

Tetraodontiformes (pufferfishes and kin) is a taxonomically and structurally diverse, widely-distributed clade of acanthomorphs, whose members often serve as models for genomics and, increasingly, macroevolutionary studies. Morphologically disparate Palaeogene fossils suggest considerable early experimentation, but these flattened specimens often preserve limited information. We present a three-dimensionally preserved beaked tetraodontiform from the early Eocene ( c. 53 Ma) London Clay Formation, UK. Approximately coeval with the oldest crown tetraodontiforms, † Ctenoplectus williamsi gen. et sp. nov. presents an unprecedented combination of characters, pairing a fused beak-like dentition with prominent dorsal-fin spines that insert atop transversely-expanded pterygiophores roofing the skull. Bayesian total-evidence tip-dating analysis indicates that † Ctenoplectus represents the sister lineage of Triodontidae and highlights considerable levels of homoplasy in early tetraodontiform evolution. According to our dataset, rates of morphological character evolution were elevated at the origin of crown Tetraodontiformes, especially within gymnodonts, but declined after the principal body plans were established. Such 'early burst' patterns are regarded as a hallmark of adaptive radiations, but are typically associated with diversification at smaller spatiotemporal scales. However, denser sampling of Neogene and Recent taxa is needed to confirm this pattern. [ABSTRACT FROM AUTHOR]

The oldest talpid, Eotalpa, was previously known only from isolated cheek teeth from the European late Middle Eocene to earliest Oligocene. Screenwashing of Late Eocene sediments of the Hampshire Basin, UK, has yielded cranial and postcranial elements: maxilla, dentary, ulna, metacarpals, distal tibia, astragalus, calcaneum, metatarsals and phalanges. In addition to M1-2 myotodonty, typical talpid features are as follows: ulna with long medially curved olecranon and deep abductor fossa and astragalar body with lateral process. However, Eotalpa retains certain soricid-like primitive states ( M1 preparacrista, P4 with prominent mesiolingual protocone lobe, strongly angled astragalar neck and calcaneum with no space for a cuboid medial process) not found in modern talpids. Eotalpa is more derived than the most primitive living talpid Uropsilus in having lost the M1-2 talon shelf, developed a convex radial facet on the ulna, an incipient proximal olecranon crest, relatively shorter metapodials and depressed manual unguals. Its astragalus with medial trochlear ridge taller than the lateral one and massive medial plantar process is typical of the Lipotyphla. Eotalpa lacks synostosis of tibia and fibula, found in other Talpidae, Soricidae and Erinaceidae, suggesting that synostosis in these groups has been independently acquired. Cladistic analysis places Eotalpa as stem member of the Talpidae and shows that much homoplasy arose during the early evolution of the family. Ground dwelling in Eotalpa is indicated by the following: astragalus with a medially dipping head, curved in a single plane; calcaneum with distal peroneal process and strongly overlapping ectal and sustentacular facets; and matching sized ectal and sustentacular facets on calcaneum and astragalus. These features would have restricted ankle mobility. Ungual and metatarsal shape and ulnar structure suggest a primitive stage in fossorial evolution and argue against a semiaquatic precursor stage in talpid fossoriality. Shrew-moles may represent a reversal to surface foraging rather than an intermediate stage in fossoriality. [ABSTRACT FROM AUTHOR]

A humerus and a coracoid from the Early Eocene Wasatch Formation in the Washakie Basin of south-western Wyoming are the oldest materials (by ~2 million years) of the pelecaniform Limnofregata (Aves) and represent a new large species, Limnofregata hutchisoni sp. nov. This fossil is the oldest known member of the frigatebird lineage. Other than its large size relative to Limnofregata azygosternon and L. hasegawai, the new material is very similar morphologically to other known Limnofregata specimens. The size of this new species is comparable to the largest living species (e.g. Fregata minor and Fregata magnifiscens) and much larger than the two described species of Limnofregata. This fossil indicates that the hard minimum date previously advocated for molecular calibration of the split between Fregatidae and Suloidea is an underestimate by approximately two million years. The presence of early pelecaniform bird lineages (represented by Limnofregata and Masillastega) in limnic ecosystems prior to their known occurrences in marine deposits/habitats appears to indicate that some clades of pelecaniform birds may have undergone an evolutionary transition from freshwater to marine habitats in a pattern reminiscent of what has been suggested during the evolution of pinnipeds or that their palaeoecology included broader niches ranging across a variety of aquatic habitats. That transition in habitat occupation and the origin of many of the characteristic biological aspects present in the crown frigatebird clade likely occurred during a significant temporal gap (> 45 million years) in the fossil record of the frigatebird lineage after these earliest occurrences in the Early Eocene and before the oldest records of the extant Fregata species in the Pleistocene. [ABSTRACT FROM AUTHOR]

Hantkenina is a distinctive planktonic foraminiferal genus characterized by the presence of tubulospines (robust hollow projections) on each adult chamber, from Middle and Upper Eocene marine sediments worldwide. Here we illustrate its evolutionary origin using c. 150 specimens from 30 stratigraphic intervals in two sediment cores from Tanzania. The specimens, which span an estimated time interval of 300 ka, show four intermediate steps in the evolution of the tubulospines that amount to a complete intergradation from Clavigerinella caucasica, which does not possess them, to Hantkenina mexicana, which does. Stable isotope analyses indicate that the transitional forms evolved in a deep planktonic habitat not occupied at that time by other species of planktonic foraminifera. We discuss the morphogenetic constraints involved in the evolutionary transition and propose an ecological/adaptive model for the selective pressures that resulted in the evolution of tubulospines. We compare our record with similar, recently described assemblages from Austria and Italy, and we update the biostratigraphy and systematic taxonomy of the key morphospecies involved in the transition. [ABSTRACT FROM AUTHOR]

The first Sinopa species, S. jilinia sp. nov., from outside of North America is described. It comes from the Huadian Formation, locality Gonglangtou, Jilin Province, north-east China. The new species represents the northernmost and one of the latest and most complete Asian Prototomus-like hyaenodontidans known. It also represents one of the youngest specimens of Sinopa, because the age of the Huadian Formation is correlated to the later Uintan and only one doubtful citation of North American Sinopa younger than the early Uintan exists. S. jilinia sp. nov. is characterized by having m3 clearly smaller than m1, very strong and extended labial molar cingulids, backward leaning protoconids in all molars and its m3 cristid obliquum joining the postvallid very labially. With S. jilina, Sinopa is the first hyaenodontidan genus known to be present on two continents during the time interval between the earliest Eocene ( c. 55.0 Ma) and latest middle Eocene (40 Ma). Its occurrence in the Huadian Formation supports the idea of a faunal exchange between North America and Asia in the early middle Eocene, a hypothesis formerly based mainly on the presence of the omomyid primate Asiomomys in the Huadian Formation, on a small radiation of East Asian trogosine tillodonts and on a couple of perissodactyl genera shared between the middle Eocene of North America and the Irdinmanhan of East Asia. As with the new Sinopa species, these Asian taxa had their closest relatives in North America. [ABSTRACT FROM AUTHOR]

Two new species of pseudorhyncocyonid, Fordonia lawsoni sp. nov. and Leptictidium prouti sp. nov. from the UK earliest Eocene, described here, are older than any previously recorded member of the family. They are represented by teeth from numerous loci, which allow a better understanding of the sparsely known dentitions of currently known pseudorhyncocyonids. This facilitates the recognition of two further species of Leptictidium, L. listeri sp. nov. from the Middle Eocene of Germany and L. storchi sp. nov. from the Late Eocene of France. Study of occlusal relationships also helps to fill gaps in our knowledge of missing tooth loci. Cladistic analysis of pseudorhyncocyonids with their previously judged closest relatives, the Leptictidae, Pantolesta and Palaeanodonta, shows that two European species, Diaphyodectes prolatus and Palaeictops? levei, formerly thought to be leptictids, are instead primitive pseudorhyncocyonids, extending the range of the family further back in time to the Middle Paleocene. P? levei is placed in the new genus Phakodon gen. nov. The analysis also shows that the Pseudorhyncocyonidae are sister group to the other three groups combined and that family-level differentiation in this probable clade took place as early as the earliest Paleocene. [ABSTRACT FROM AUTHOR]

A partial quadrate (essentially the otic part) from the nonmarine, earliest Eocene (54.6 Ma) Tingamarra Local Fauna in Queensland, Australia, has been identified as the oldest Australian anseriform fossil. The Tingamarra quadrate shows a combination of plesiomorphic anseriform characters with a unique synapomorphic character complex of the Anhimidae (screamers), which today are endemic to South America. In concert with the basal position of the Anhimidae among the crown-group anseriforms, this set of characters suggests a stem group of the Anhimidae, raising a possibility of the Transantarctic migration of stem anhimids to South America. The quadrate morphology supports palaeognathous rather than recently claimed anhimid relationships of the Dromornithidae and identifies Sylviornis as an anseriform rather than a galliform. [ABSTRACT FROM AUTHOR]

A new genus and species of basal non-Viverravidae Carnivoramorpha, Dawsonicyon isami, is named and described. This new taxon is based upon DMNH 19585, an almost complete skeleton, which was collected from the Black’s Fork Member (informal ‘Bridger B’ subunit) of the Bridger Formation in southwestern Wyoming, USA. The specimen is incorporated into an existing craniodental data matrix, and the associated phylogenetic analyses support the identification of this species as a new basal carnivoramorphan. This new taxon is dentally compared to all known genera of non-viverravid basal carnivoramorphans, as well as with all known species of the problematic genus Miacis. Postcrania are compared in detail with other described specimens of non-viverravid basal carnivoramorphans and more generally with known postcrania of viverravids. Preliminary functional interpretations of a scansorial locomotor mode are offered for this new taxon. Its implications for the diversity of middle Eocene basal carnivoramorphans is briefly discussed, including expansion of the already high diversity in the Black’s Fork Member of the Bridger Formation (at least 11 species in 8 genera). [ABSTRACT FROM AUTHOR]

We describe a new, exceptionally well-preserved fossil bird recovered from marine deposits of the Early Eocene Fur Formation of Denmark. Morsoravis sedilis gen. et sp. nov. is known by a single specimen that consists of a three-dimensional skull, vertebral column, ribs, pelvis, and left hindlimb and associated parts of the right hindlimb. Comparisons based on overall morphology and particularly characters of the skull, vertebrae and pelvis indicate that the new specimen is morphologically similar to charadriiform birds (the shorebirds and relatives). This similarity is also expressed by a phylogenetic analysis of higher neornithine (modern birds) taxa, which supports a close relationship between the new fossil and modern charadriiforms. The morphology of the hindlimbs, in particular, shows that the new fossil corresponds to a new taxon that is distinguishable from modern charadriiform clades. One interesting aspect of its morphology is the presence of hindlimb specializations that are most commonly found among perching birds – these suggest that ecologically the new Danish fossil bird may have differed from the wading habits typical of most charadriiforms. [ABSTRACT FROM AUTHOR]

The controversial taxon Colombitherium tolimense (Mammalia) (probably Late Eocene in age) from Colombia, although known for nearly 40 years, still bears much mystery. Aside from the problematic ordinal attribution of the holotype and only specimen, its determination as an upper or lower jaw remains a highly debated issue. New observations include the presence of a contact facet on the distal face of the most posterior tooth, which indicates that the fragmentary jaw preserves three premolars and two molars; the M3, unpreserved but present, being most probably reduced. This new interpretation completely fits the morphology of the teeth. Furthermore, the shape of these latter and the deeper wear encompassed by their lingual part relative to the labial one is typical of upper dentition. This is in agreement with the internal curving of the roots of the anterior premolars and with several other arguments that lead interpreting the holotype of C. tolimense as a maxillary bearing P2-M2. This new interpretation deepens the morphological gap between Colombitherium and other pyrotherians (except Proticia) and challenges further its referral to Pyrotheria. The peculiar morphology of Colombitherium relative to other pyrotherians is indeed striking. In fact, Colombitherium has nothing in common with pyrotherians but bilophodont cheek teeth, a feature largely widespread in placental mammals. It is here referred to ?Pyrotheria until additional evidence of its relationships is known. Associated with the putative removal of Proticia from Pyrotheria as argued by some authors, the hypothetical removal of Colombitherium from the order would adjust the widely accepted assumption that the pyrotherian bilophodont cheek teeth originated from bunodont cheek teeth. It would also make an origin from lophodont forms plausible. This in turn would have critical relevance, especially to the hypothesis that pyrotherians are notoungulates. [ABSTRACT FROM AUTHOR]

Eophryne  barbutii gen. et sp. nov., a new frogfish from the Ypresian of Monte Bolca (Italy), is described. This taxon is the oldest member of the family Antennariidae known to date based on articulated skeletal remains. Eophryne  barbutii gen. et sp. nov. possesses a unique combination of features that supports its recognition as a new genus of the family Antennariidae. It is characterized by the presence of tiny bifurcated dermal spinules on the skin between and on the surface of the second and third dorsal-fin spines, a naked illicium, outermost caudal-fin rays simple, caudal peduncle present, 11 dorsal-fin rays, and seven anal-fin rays. Eophryne gen. nov. shows a certain degree of phenetic resemblance to the extant genera Antennarius, Histrio and Nudiantennarius. Palaeoecological and evolutionary implications are also discussed. [ABSTRACT FROM AUTHOR]

The giant bivalve Lucina megameris Dall, 1901 , from the late Eocene White Limestone Group of Jamaica and by far the largest known species of the family Lucinidae, is placed in a new genus Superlucina. Apart from its large size, with a shell height exceeding 310 mm, it is distinguished from other genera, such as Pseudomiltha and Eomiltha by external shell characters and the extremely long and narrow, anterior adductor muscle scar. Features preserved on internal moulds suggest that, in common with living Lucinidae, S. megameris was chemosymbiotic with sulphide – oxidizing bacteria housed in the gills. Palaeoenvironmental evidence suggests a habitat in oligotrophic, shallow waters, probably in seagrass beds, with an associated molluscan fauna including large cardiids that may have been photosymbiotic. Superlucina is considerably larger than any living lucinid that range in size from 3 to 150 mm with most encompassed within 5–30 mm. From the Jurassic onwards, a few other large lucinids are known from cold seep sites, with several other records from possible shallow water seagrass beds. [ABSTRACT FROM AUTHOR]

The first substantial skull of a very large Paleogene bony-toothed bird (Pelagornithidae) is described from the Lower Eocene London Clay of the Isle of Sheppey in England. The specimen is assigned to Dasornis emuinus (Bowerbank), based on a taxonomic revision of the large London Clay Pelagornithidae. Very large bony-toothed birds from the London Clay were known previously from fragmentary remains of non-comparable skeletal elements only, and Dasornis londinensis Owen, Argillornis emuinus (Bowerbank), A. longipennis Owen, and Neptuniavis miranda Harrison and Walker are considered junior synonyms of D. emuinus. The new specimen allows a definitive assignment of Dasornis to the Pelagornithidae and documents that this taxon closely resembles other bony-toothed birds in cranial morphology. It is hypothesized that giant size (i.e. a wingspan above 4 m) evolved only once within Pelagornithidae and that Dasornis emuinus is the sister taxon of the giant Neogene bony-toothed birds, which share a derived wing morphology. [ABSTRACT FROM AUTHOR]

Two new fossil psittaciform birds from the Lower Eocene ‘Mo Clay’ (Fur Formation) of Denmark ( c. 54 Ma) are described. An unnamed specimen is assigned to the extinct avian family of stem-group parrots, Pseudasturidae (genus and species incertae sedis), while a second ( Mopsitta tanta gen. et sp. nov.) is the largest fossil parrot yet known. Both specimens are the first fossil records of these birds from Denmark. Although the phylogenetic position of Mopsitta is unclear (it is classified as family incertae sedis), this form is phylogenetically closer to Recent Pstittacidae than to other known Palaeogene psittaciforms and may, therefore, represent the oldest known crown-group parrot. [ABSTRACT FROM AUTHOR]

New specimens of Peratherium africanum from Early Oligocene deposits of the Fayum, Egypt, provide key information on the relationships of the species. These include the first maxilla to be found and two additional dentaries. The maxilla can be demonstrated to belong to the same species as the holotype dentary by study of the occlusal relationships of upper and lower molars. It can be shown by several synapomorphies that P. africanum is the sister species to European Bartonian–Rupelian Peratherium lavergnense. P. africanum therefore belongs to the ‘didelphimorph’ family Herpetotheriidae, not to the peradectimorph family Peradectidae. The genus Qatranitherium, previously erected for this species alone, is here synonymized with Peratherium. Comparison with ‘didelphimorphian’ taxa from early Paleogene deposits of South America suggests more remote relationships, indicating an origin for P. africanum by dispersal from Europe as originally envisaged. The more precise relationships deduced here help to constrain the time interval for dispersal to Afro-Arabia, probably during the earliest Oligocene sea-level low. [ABSTRACT FROM AUTHOR]

Eodysagrion mikkelseni gen. et sp. nov., type species of the new subfamily Eodysagrioninae, and the dysagrionine Primorilestes madseni sp. nov., the first thaumatoneurid damselflies from the lowermost Eocene of Denmark, are described. They confirm the presence of this American family in the Palaeogene of Western Europe. [ABSTRACT FROM AUTHOR]

The first fossil records of Holarctic representatives of the genus Comptosia Macquart, 1840 from the middle Eocene Messel Pit, Germany, and the upper Eocene of Florissant, USA, are reported. The fossil from Messel, Comptosia pria sp. nov., is represented by a well-preserved wing, displaying characteristic wing venation, remains of the second wing and elements of the thorax. The Florissant fossil, C. miranda comb. nov., is preserved almost completely with both wings and most parts of the body visible. Extant members of the genus Comptosia are currently found only in Australia, and close relatives are known from southern South America. Previously this group of genera has been thought to be of Gondwanan origin, but these Eocene fossil representatives of Comptosia from the Holarctic region argue against this interpretation, and suggest that Comptosia and its relatives were more widespread in both Northern and Southern hemispheres during the Palaeogene. The fossil record of bee flies suggests a major radiation of bombyliids in the late Cretaceous or early Cenozoic. This assumption is supported by the comparatively young geological age of many bombyliid host taxa. A key factor driving the specialization of many bombyliid larvae on ground-dwelling hosts may have been avoidance of competition with tachinid flies and parasitic hymenopterans. [ABSTRACT FROM AUTHOR]

The holotype of Dollosuchus dixoni (Owen) from the Early–Middle Eocene Bracklesham Beds of England is a set of mandibular fragments that cannot be distinguished from corresponding parts of other longirostrine crocodylians. An isolated humerus from the Bracklesham Beds is consistent with a gavialoid, but it cannot be referred to the holotype of D. dixoni. The name Dollosuchoides densmorei is established for the well-preserved skull and skeleton of a tomistomine from the Middle Eocene of Belgium that had been referred to D. dixoni. It can be clearly distinguished from the basal tomistomine ‘ Crocodilus’ spenceri Buckland from the Lower Eocene of England, which cannot be referred to Dollosuchoides and is provisionally referred to Kentisuchus Mook. Although basal within Tomistominae, Dollosuchoides is more closely related to Tomistoma than to Kentisuchus. [ABSTRACT FROM AUTHOR]

An ossified auditory bulla of a basal carnivoran is described for the first time. Although broken, the bulla of Viverravus acutus (Viverravidae, Carnivora) appears to have enclosed the middle ear and to have been composed exclusively of an ectotympanic bone. The structure of the bulla and other basicranial features support the hypothesis that viverravids lie phylogenetically outside crown-group Carnivora and that the last common ancestor of living carnivorans may have existed as recently as 42 million years ago, not 60–70 million years ago as suggested by some authors. [ABSTRACT FROM AUTHOR]

A new species of Moeritherium (Proboscidea, Mammalia), M. chehbeurameuri sp. nov., is described from remains discovered in the early late Eocene locality of Bir El Ater, Algeria. Although mainly represented by isolated teeth, it shows distinct synapomorphies which justify its attribution to the genus Moeritherium, together with exclusive features that led to the creation of the new species. The main characteristic of this new taxon is the almost complete lophodonty shown by its molars, while Moeritherium is commonly regarded as a bunolophodont to bunodont taxon. In addition to this lophodonty, this new taxon shows anatomical features as yet unknown for the genus, but often met within lophodont early proboscidean taxa such as Phosphatherium escuilliei and Numidotherium koholense. Although a revision of the whole genus Moeritherium is outside the scope of this paper, the main controversies and discussion about the definition of species within the genus Moeritherium are discussed. The surprising lophodonty of M. chehbeurameuri, together with its small size, its early late Eocene age and the weak molarization of its P3 support the hypothesis of a lophodont hypothetical ancestor for moeritheres, and therefore strengthen the growing hypothesis of a lophodont dental ancestral morphotype for proboscideans. [ABSTRACT FROM AUTHOR]

A new genus of cantacaderid lace bugs, Lutetiacader gen. et sp. nov., is described from the lower Middle Eocene of Messel Quarry, Germany. It clearly belongs to the cantacaderid lineage of Tingidae, and is the second known fossil genus of the tribe Cantacaderini (after Paleocader Froeschner). It appears to be most similar to extant species of the genera Nectocader Drake (Brazil) and Teratocader Drake (Malay Peninsula). Lutetiacader occupies a central position with respect to the geographical gap between the ranges of these two extant genera. Its biogeographical significance is discussed. [ABSTRACT FROM AUTHOR]

The fossiliferous site of Mahenge, Tanzania, interpreted as a small lake that formed in a kimberlite intrusion, has yielded a vertebrate assemblage that includes scarce frog remains. Radiometric dating of the pipe indicates that the volcanic activity took place at 45·83 ± 0·17 Ma, whereas infilling of the crater was completed in 0·2–1·0 myr after emplacement. The frogs, described herein, are preserved as partially articulated skeletons that represent a new pipine taxon, Singidella latecostata gen. et sp. nov. A parsimony analysis of fossil and extant pipoid frogs indicates that Singidella is more closely related to African Hymenochirus and Pseudhymenochirus than to South American Pipa. It also provides weak support for the sister-group relationship of Singidella and the bizarre Late Cretaceous Pachycentrata taqueti (replacement name for Pachybatrachus taqueti) from Niger, although the incomplete preservation of Pachycentrata precludes thorough comparisons. This record indicates that prior to the rifting in the Miocene the distribution of pipines extended into eastern Africa where they do not occur today. [ABSTRACT FROM AUTHOR]

The specimens previously described asLingula antarcticaBuckman from late Eocene strata on Seymour Island, Antarctic Peninsula, should be assigned to the genusGlottidia. The morphological features and taxonomic characters ofG. antarcticaare described and illustrated and compared with those of other known species ofGlottidia. A full description ofG. antarcticais provided and the diagnosis of the genus is emended. Variations in the disposition of the septa and in the shape of the pedicle groove are viewed as evolutionary features among theGlottidia.Glottidia antarcticaprobably lived in shallow, nearshore warm-temperate waters of normal salinity, perhaps in the intertidal zone. The presence ofGlottidiarather thanLingulain the Antarctic Peninsula is consistent with the known geographical distribution of fossil and livingGlottidia, i.e. restricted to the coasts of the American continent and Europe whereGlottidiahas been recorded in strata of Tertiary age. [ABSTRACT FROM AUTHOR]

Worm tubes, which exhibit the replaced tube-lining membrane, have been collected from the lowermost Lower Eocene Acantilados Allomember of the La Meseta Formation, Seymour Island, Antarctica. The discovery represents the oldest examples of preservation of the tube-lining membrane of tube-dwelling Polychaeta in the fossil record. A new genus and species,Caprascolex antarcticus, are described. The specimens are preserved as thin coatings of amorphous iron oxide on the inner surface of the moulds interpreted to be the replaced tube-lining membrane. Examination of the rarely described tube-lining mucosoid membrane in extant polychaetes shows that the fossils are nearly identical in morphology and scale to extant forms. These fossils record in remarkable detail the morphology of the tube-lining membrane, which appears to be composed of growth bands formed as the worm constructed the tube. The tube-lining is believed to have been originally preserved as pyrite, with subsequent oxidation to iron oxide. The tube-lining membrane of worm tubes possibly is known from only one other fossil occurrence. [ABSTRACT FROM AUTHOR]

Sediments at the Red Hot Truck Stop (RHTS), Mississippi, USA are important because they contain the lowest latitude record of both the earliest known Eocene plant and mammal fossils in North America. The RHTS contains the uppermost Tuscahoma Formation and the lowermost part of the basal Bashi and Hatchetigbee formations. The Tuscahoma Formation is composed of glauconitic sands and silts that represent estuarine to shallow marine sediments. Faunal remains indicate that the RHTS section belongs to the Wasatchian North American land mammal age and specifically to the lower Graybullian subdivision. Pollen and spore floras from the RHTS are moderately diverse (113 taxa) and contain families that today are associated with warm-adapted vegetation types such as Annonaceae, Bombacaceae, Burseraceae and palms. Eocene first occurrences are represented by Brosipollis sp., Celtispollenites sp., Interpollis microsupplingensis, cf. Nuxpollenites psilatus, Platycarya spp., Retistephanocolporites sp. and Symplocos? contracta and by one genus of pteridophyte spore (Granulatisporites sp.). The overall composition and within-sample diversity of the sporomorph flora is more similar to the Hatchetigbee Formation (early Eocene) than to the middle Tuscahoma Formation (late Palaeocene) but among-sample diversity remains unchanged across the Palaeocene/Eocene boundary. The distinct composition of the RHTS demonstrates that floral change across the Palaeocene/Eocene boundary is complex and composed of several phases of floral change. [ABSTRACT FROM AUTHOR]