Late Cretaceous radiolarians of the genera Cuboctostylus Bragina and Hexacromyum Haeckel: Their stratigraphic and paleobiogeographical distribution

Recently, representatives of the genus Cuboctostylus Bragina (order Entactinaria) were included in the Upper Cretaceous radiolarian regional stratigraphic scale of Sakhalin. The Late Cretaceous species Hexacromyum pergamenti Bragina (order Spumellaria) has morphological similarity to representatives of the genus Cuboctostylus. Peculiar features of H. pergamenti internal structure are considered. Collections of Upper Cretaceous radiolarians from southern Cyprus, Serbia, northern Turkey, Crimean Mountains, East European Platform, northwestern Kamchatka, eastern slope of the Sredinnyi Range in Kamchatka, and Shikotan Island (Lesser Kurile Range) were used for the analysis of the taxonomic composition of Late Cretaceous representatives of the genera Cuboctostylus Bragina and Hexacromyum Haeckel as well as their stratigraphic and paleobiogeographic distribution. It is established that Cuboctostylus is distributed from tropical to south boreal realms. This genus is shown to exist through almost the entire Late Cretaceous: from the middle Cenomanian to initial Maastrichtian. Hexacromyum Haeckel populated both the south boreal realm and marginal areas of the Tethys Ocean in the Late Cretaceous. The new data presented may be used for distant interregional correlations. Cuboctostylus stellatus sp. nov. and several other Cuboctostylus taxa identified in open nomenclature are described; some morphological features of Hexacromyum pergamenti are specified.     

Osteoderms of Montealtosuchus arrudacamposi (Crocodyliformes,Peirosauridae) from the Turonian-Santonian (Upper Cretaceous) of Bauru Basin,Brazil

The skin of Crocodyliformes is characterized by osteoderms of various sizes and shapes. It plays roles in defence, thermoregulation, sexual attraction, calcium reserves, and locomotion. This study presents the morphometric characteristics of osteoderms preserved in the nuchal, dorsal, ventral and appendicular shield of Montealtosuchus arrudacamposi, a Peirosauridae crocodyliform from the Turonian-Santonian (Upper Cretaceous) of Adamantina Formation, Bauru Basin, Brazil. The results of the analysis show that its dermal shield had protective and thermoregulatory functions and a well-defined mechanical function allowing terrestrial locomotion and enabling good agility and capacity for movement.     

A new genus and species of soldier beetle from Upper Cretaceous Burmese amber (Coleoptera,Cantharidae, Malthininae)

A new Upper Cretaceous genus and species of soldier beetles, Archaeomalthodes rosetta gen. et sp. nov., is described and illustrated from an individual preserved in Upper Cretaceous (Cenomanian, ca. 99 Ma) amber from northern Myanmar. It is undoubtedly placed in extant subfamily Malthininae based on its small-sized body, somewhat abbreviated elytra and fusiform terminal maxillary palpomere, representing the oldest documented occurrence of Malthininae. It suggests that this subfamily is an ancient group, which originated at least in the earliest Late Cretaceous. Our discovery sheds light on the palaeodiversity of Cantharidae in the Late Mesozoic. Together with other previously reported fossil cantharids, it is likely that Malthininae has been fairly diverse during the early evolution of Cantharidae. On the other hand, a morphological similarity between Archaeomalthodes and Recent malthinines and the occurrence of flowering plants in the Burmese amber implies a potential flower-visiting behaviour of this fossil species.     

Frullania pinnata spec. nov. (Frullaniaceae,Porellales), a new leafy liverwort in mid-Cretaceous Burmese amber from Myanmar

An inclusion in Cretaceous amber from Myanmar is described as a new fossil species in the extant liverwort genus Frullania. The name Frullania pinnata is proposed for the taxon that is characterized by entire underleaves paired with a conspicuous pinnate branching pattern, two distinctive and stable morphological features. Entire underleaves are known in several extant Frullania species but had not previously been documented in Frullania in amber. The combination of morphological characters in this new fossil species is unknown in any crown group lineage of Frullania, and may very well represent a stem lineage element of the genus. This discovery is important because it expands our understanding of the diversity of Frullaniaceae in the Burmese amber forest as well as important ramifications for the phylogenetic reconstruction of extant Frullania lineages.     

Gondwanasuchus scabrosus gen. et sp. nov., a new terrestrial predatory crocodyliform (Mesoeucrocodylia: Baurusuchidae) from the Late Cretaceous Bauru Basin of Brazil

Baurusuchids are among the most common and diverse crocodyliform fossils from the Late Cretaceous Bauru Basin of Brazil. This inland continental basin was the habitat of a rich crocodyliform fauna containing five mesoeucrocodylian families, of which the Baurusuchidae represents highly specialized predatory crocodyliforms of terrestrial habits as indicated by their dental, cranial, and postcranial features. The large size they achieved, together with likely predatory adaptations, would suggest they competed and occupied theropod ecological niches in the Bauru Basin. Here we describe Gondwanasuchus scabrosus gen. et sp. nov., a medium-sized baurusuchid with a strongly laterally compressed skull, bearing unique dentition with deep apicobasal sulci and probably well-developed binocular vision. The cranial and dental features in Gondwanasuchus suggest that this active predator would have fed on small vertebrates and took the role of small theropods in terrestrial guild. Gondwanasuchus is the most distinctive baurusuchid known to date and enriches the knowledge on these important Gondwanan terrestrial predatory crocodyliforms.     

A new ornithopod (Dinosauria,Ornithischia) from the Upper Cretaceous of Antarctica and its palaeobiogeographical implications

A new ornithopod dinosaur from the Upper Cretaceous (Maastrichtian) Snow Hill Island Formation, at James Ross Island, Antarctica is here described. This new taxon, named as Morrosaurus antarcticus gen. et sp. nov., is represented by a fragmentary right hind limb belonging to a medium-sized individual. Our phylogenetic analysis nests the new taxon in a monophyletic clade of Southern Hemisphere ornithopods that includes most Patagonian and Antarctic ornithopods. Several members of this group share a slender and bunched foot with narrow metatarsal IV, expanded chevrons, and bowed humerus without deltopectoral crest. Several features indicate that these ornithopods exhibit adaptations for a specialized cursorial mode of life. The recognition of Patagonian and Antarctic Ornithopoda belonging to a monophyletic clade reinforces palaeobiogeographical signals indicating that Patagonia, Antarctica and Australia shared a common Late Cretaceous terrestrial fauna.     

A new genus and species of polypore fungus beetle in Upper Cretaceous Burmese amber (Coleoptera,Tetratomidae, Eustrophinae)

A new polypore fungus beetle is described and figured from an individual preserved in Upper Cretaceous (Cenomanian, ca. 99 Ma) amber from northern Myanmar. Cretosynstrophus archaicus gen. et sp. nov. is confidently placed in the extant subfamily Eustrophinae based on its elongate oval body and pronotum with two basal, sublinear impressions. It shares several characters belonging to two Recent tribes (Eustrophini and Holostrophini), but it cannot be attributed to either of them. Together with other tetratomid genera from the Cretaceous, the new discovery implies that the Recent small family Tetratomidae is much more diverse and more widespread than previously documented. In addition, a morphological similarity between Cretosynstrophus and extant Synstrophus suggests a similar fungi feeding habit for Cretosynstrophus, highlighting an ancient association between tetratomid beetles and fungi in the Mesozoic.     

Spinotoma ruicheni: A new Late Cretaceous genus and species of wedge-shaped beetle from Burmese amber (Coleoptera,Ripiphoridae, Pelecotominae)

A new genus and species of ripiphorid beetle is described based on a female specimen preserved in Upper Cretaceous (Cenomanian, ca. 99 Ma) amber from northern Myanmar, under the name of Spinotoma ruicheni gen. et sp. nov. It belongs to the extant Pelecotominae and represents the second documented occurrence of this subfamily in the Late Cretaceous. This new taxon is morphologically distinguishable in Pelecotominae by the combination of following characters: eyes oval, without incision; antennomeres V–X serrate, with XI fusiform; maxillary palpi unmodified; protarsi shorter than protibiae; tibiae sparsely provided with spines; tibial spurs formula 2-0-2. Together with other previously reported fossil ripiphorids, it highlights the species diversification of wedge-shaped beetles during their early evolution. On the other hand, a morphological similarity between Spinotoma and modern pelecotomines and the occurrence of xylophagous beetles in the Burmese amber suggest a similar host preference in wood-boring beetles for this species, shedding lights on an ancient host-parasitoid relationship in the late Mesozoic. This paper also provides a brief discussion on the taxonomy and evolution of Mesozoic wedge-shaped beetles. The wedged-shaped body form and fully-developed elytra in Recent Pelecotominae and Ptilophorinae are considered to be derived from their early ancestors rather than evolved with the onset of flowering plants during the Cretaceous as commonly thought.     

A stegosaur tooth (Dinosauria, Ornithischia) from the Early Cretaceous of southwestern France

The spotty nature of the terrestrial fossil record for the Mesozoic hinders a more complete understanding of dinosaur diversity. For stegosaurs (Ornithischia), the plated dinosaurs, only a few and fragmentary remains are reported from the Early Cretaceous of Europe. A recent revision concluded that only a partial vertebra of the nomen dubium Craterosaurus (?Aptian, England) could be considered as stegosaurian. Here we report on a stegosaur tooth from the Early Cretaceous (Berriasian) Purbeckian deposits of Cherves-de-Cognac (Charente), southwestern France. This tiny tooth was examined in detail using microtomography. Comparisons being limited by the rarity of stegosaur tooth rows material (e.g., from the skull of the holotype of Stegosaurus stenops) and dental material, notably from Europe, we observed new material of cf. Stegosaurus armatus and Hesperosaurus mjosi from the Upper Jurassic Morrison Formation of Wyoming (USA). The tooth shows the most similarities to the Late Jurassic genera Stegosaurus and Hesperosaurus, but differs in having a distinctive downwardly arched (V-shaped) cingulum on the ?lingual face (maxillary tooth hypothesis). It is referred to as Stegosauria indeterminate, a medium-sized quadrupedal herbivore that inhabited an emerged land between the Armorican Massif and the Massif Central. This finding is the first evidence of a stegosaur from the Early Cretaceous of France and a welcome addition to the meagre European record of that time. In addition, it is the second stegosaurian tooth crown reported from Europe. The assemblage of ornithischians of Cherves-de-Cognac shares some similarities with that of the Early Cretaceous (Berriasian) of the Purbeck Limestone Group, southern England. The relative rarity of ornithischian osteological remains in both Purbeckian environments suggests that most of these dinosaurs were mainly inhabitants of inland terrestrial palaeoenvironments.     

Taxonomic composition,paleoecology and biostratigraphy of Late Cretaceous diatoms from Devon Island,Nunavut, Canadian High Arctic

Upper Cretaceous sediments of the Kanguk Formation exposed in Eidsbotn and Viks Fiord grabens on Devon Island, Nunavut, Canadian High Arctic, yielded 91 fossil marine diatom species and varieties (including indeterminate taxa), representing 41 genera. Excellent preservation of the assemblages was aided by shallow burial, protection in downfaulted linear grabens, and the presence of abundant volcanic material. Planktonic species and resting spores comprise nearly 70% of the diatom assemblage, and provided abundant food resources for the Late Cretaceous Arctic ecosystem. Deposition of the approximately 225 m-thick stratigraphic sequence was predominantly in a shallow marine neritic setting, with an upward progression to interbedded terrestrial deposits of the Expedition Fiord Formation, reflecting a regression and eventual persistence of terrestrial facies into the Early Cenozoic. The Kanguk Formation is widespread across the Canadian Arctic, and diatom biostratigraphy indicates a Santonian–Campanian age for the sequences reported herein, based on the presence of Gladius antiquus in the lowermost strata and occurrence of Costopyxis antiqua throughout the succession. However, Amblypyrgus sp. A and Archepyrgus sp. aff. A. melosiroides, encountered in the lower part of the succession, are known exclusively from the Lower Cretaceous. This may suggest a slightly older age. New information on shallow shelf diatom assemblages from this study is compared to reports on two other Late Cretacous Arctic diatom assemblages. These three sites represent an environmental transect from shallow to distal shelf settings and into the oceanic realm.     

First record of Procyon cancrivorus (G. Cuvier, 1798) (Carnivora,Procyonidae) in stratigraphic context in the Late Pleistocene of Brazil

Although five genera of procyonids are currently present in South America, only two of the extant genera, Procyon and Nasua are represented in the South American fossil record. A recent discovery of a procyonid lower second molar in Late Pleistocene deposits of Aurora do Tocantins, northern Brazil, offers potential to further our understanding of the stratigraphic and temporal range of South American fossil procyonids. We use geometric morphometric analysis of two-dimensional landmarks and semilandmarks to explore morphological variation in the lower second molars of extant Procyon lotor and Procyon cancrivorus and multivariate methods to support the identification of the Pleistocene specimen as P. cancrivorus. This material represents the second fossil record of P. cancrivorus in South America Procyonids entered South America in two phases: the first comprising by Cyonasua and Chapadmalania during the Late Miocene, and the other recent genera, beginning in the Late Pleistocene. These Late Miocene procyonids were more carnivorous than Late Pleistocene-Recent omnivorous taxa and possible went extinct due to competition with other placental carnivorans that entered South America and diversified during the latest Pliocene-Early Pleistocene.     

First Lower Cretaceous record of Podocarpaceae wood associated with dinosaur remains from Patagonia,Neuquén Province,Argentina

The first Podocarpaceae wood record is described from the Mulichinco Formation (Valanginian, Lower Cretaceous), Neuquén Basin, Argentina. The specimen was directly associated with a middle caudal vertebra of a diplodocid sauropod dinosaur. A new species – Podocarpoxylon prumnopityoides – is proposed based on features that include the presence of abietinean wood type (tracheid radial pitting), plus podocarpoid (cupressoid type) and some dacrydioid (taxodioid type) cross-field pits, diffuse axial parenchyma and low rays. This combination of anatomical characters is comparable to both Prumnopitys and Podocarpus, whereas the type of pits in the cross-fields resembles some members of the extant Prumnopitys. This is the first unequivocal record of the Family Podocarpaceae in the Valanginian of South America and confirms the hypothesis that the divergence between the “Podocarpoid-Dacrydioid” and “Prumnopityoid” clades occurred earlier than the Early Cretaceous.     

The first Mesozoic palmetto beetle (Coleoptera: Smicripidae) in Upper Cretaceous Burmese amber

Fossil smicripid beetles are very rare. Here we describe and figure the first Mesozoic representative of Smicripidae. Smicrips cretacea sp. nov., a new species belonging to the extant Smicrips LeConte is preserved in the Upper Cretaceous amber from northern Myanmar. Our discovery suggests that Smicrips is an ancient group, originating at least in the earliest Late Cretaceous. Together with other two fossil Smicrips species from the Eocene of Europe, it reinforces the hypothesis that the Recent distribution of Smicripidae is relict, and the family was more widespread in the Mesozoic and early Cenozoic than it is in the Recent.     

Cretaceous amber inclusions of Spain and Myanmar demonstrate early diversification and wide dispersal of Cephenniitae (Coleoptera: Staphylinidae: Scydmaeninae)

The taxonomic status of previously misplaced species of an ant-like stone beetle from Spanish amber (Albian) is clarified. Specimens of Kachinus magnificus (originally placed as incertae sedis within Scydmaenitae) were re-examined and their characters were found different from those of the type species of Kachinus from Myanmar amber. Consequently, Archeutheia gen. nov. is proposed to accommodate the Spanish species, resulting in Archeutheia magnifica comb. nov. Moreover, in a comprehensive phylogenetic analysis Archeutheia was placed as a sister group to extant Eutheia, within the tribe Eutheiini of Cephenniitae. A specimen of an undetermined genus from Myanmar amber clearly belonging in Cephenniini is also recorded. Both taxa represent the first definite Cretaceous Cephenniitae, a supertribe whose recent members are distributed on all continents but are especially diverse in the Oriental and East Palaearctic regions. This finding demonstrates a diversification of two presently most species-rich tribes of Cephenniitae already in Early Cretaceous. Archeutheia is strikingly similar to the extant species of Eutheia and Veraphis, showing male dimorphic characters (modified protrochanters) and antennal cavities characteristic of Palaearctic Eutheiini. This fact suggests a long morphological stability in the supertribe. A previously proposed hypothesis of an early presence of the Cephenniitae in the Northern Hemisphere is for the first time supported by the fossil record, and the palaeolocalities (western Europe and Southeast Asia) demonstrate a wide distribution of Cephenniitae in the Cretaceous and an early split of its ancestral lineage.     

A new ornithomimid dinosaur with North American affinities from the Late Cretaceous Qiupa Formation in Henan Province of China

A partial skeleton of the ornithomimid dinosaur, discovered from the Late Cretaceous Qiupa Formation of Luanchuan County, Tantou Basin, Henan Province, China, is described here and assigned to a new genus and species, Qiupalong henanensis, with unique features (a notch on the lateral surface of the lateral posterior process of the proximal end of tibia and a small pit at the contact between astragalus and calcaneum). A phylogenetic analysis in this study suggests that it is a derived ornithomimid and form a monophyly with North American ornithomimids (Struthiomimus altus and Ornithomimus edmontonicus), sharing two characters (straight pubic shaft and large acute angle between pubic shaft and boot). Some characters (small anterior process of the pubic boot and curved pedal unguals) are seen in basal ornithomimosaurs as well, but these features in Q. henanensis are reversal. Qiupalong is the first definitive ornithomimid from outside of the Gobi Desert and is the southern-most occurrence of Late Cretaceous ornithomimid from eastern Asia, demonstrating southern extension of ornithomimid distribution in Asia.     

A new polyglyphanodontine lizard (Squamata: Borioteiioidea) from the Late Cretaceous Iharkút locality (Santonian,Hungary)

In recent years the Late Cretaceous (Santonian) terrestrial vertebrate locality at Iharkút (western Hungary) has yielded well-preserved remains of lizard taxa besides the remains of fishes, amphibians, turtles, crocodiles, pterosaurs and dinosaurs. Previously the polyglyphanodontine lizard Bicuspidon aff. hatzegiensis has been reported from Iharkút. However, recent excavations at this site produced more lacertilian remains including new polyglyphanodontine material, namely a maxilla and two dentaries which suggest the presence of a new genus in the Iharkút fauna. This previously unknown lizard (described here as Distortodon rhomboideus n. g. n. sp.) is distinct from other polyglyphanodontines such as Bicuspidon, Paraglyphanodon, Polyglyphanodon, Dicothodon and Peneteius. It differs from these genera mainly in having the lingual cusp situated more distally compared to the labial one on its bicuspid teeth located in the distal part of the tooth row, thus the crowns having a unique rhomboidal shape in occlusal view. Distortodon rhomboideus further strengthens the dominance of borioteiioid lizards in the Iharkút fauna. The growing presence of borioteiioids in European localities supports previous theories which suggest some paleobiogeographic connections between the western Tethyan archipelago and North America in the Late Cretaceous.