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Tyrannosaurids were the most derived group of Tyrannosauroidea and are characterized by having two body plans: gracile, long-snouted and robust, deep-snouted skulls. Both groups lived sympatrically in central Asia. Here, we report a new deep-snouted tyrannosaurid, Asiatyrannus xui gen. et sp. nov., from the Upper Cretaceous of Ganzhou City, southeastern China, which has produced the large-bodied and long-snouted Qianzhousaurus. Based on histological analysis, the holotype of Asiatyrannus xui is not a somatically mature adult, but it already passed through the most rapid growth stages. Asiatyrannus is a small to medium-sized tyrannosaurine, with a skull length of 47.5 cm and an estimated total body length of 3.5-4 m; or around half the size of Qianzhousaurus and other large-bodied tyrannosaurines in similar growth stages. Asiatyrannus and Qianzhousaurus are sympatric tyrannosaurid genera in the Maastrichtian of southeastern China. Asiatyrannus differs from Qianzhousaurus in that it has a proportionally deeper snout, longer premaxilla, deeper maxilla, and deeper dentary, and the cornual process of the lacrimal is inflated without developing a discrete horn. The different skull proportions and body sizes suggest that Asiatyrannus and Qianzhousaurus likely had different feeding strategies and occupied different ecological niches., (© 2024. The Author(s).)

An unpublished turtle shell from the middle Cenomanian of Vale de Figueira, near Belas (Lisbon District, Portugal), is recognized by us as collected in 1880 under the direction of Carlos Ribeiro. No turtle remains from that region had so far been figured, described or discussed from a systematic point of view. The specimen corresponds to a partial but articulated shell. It is attributed to Pleurodira and, more specifically, to Bothremydidae. Only one pre-Campanian turtle specimen was previously identified at the infrafamilial level in the Cretaceous record of Portugal. It was a partial shell from the middle Cenomanian of Nazaré (Leiria District) attributed to the bothremydid Algorachelus peregrina, a species defined in a Spanish synchronous locality (Algora, in Central Spain). Several anatomical regions in the specimen from Vale de Figueira were not preserved in the partial carapace from Nazaré, and differences in the morphology of some elements are recognized between both shells. However, the individual studied here is also ascribed to Algorachelus peregrina, these differences being justified by intraspecific variability. Therefore, the specimen represents the second evidence on the species in Portugal, being the only one recognized for the Lisbon District., (© 2024 The Authors. The Anatomical Record published by Wiley Periodicals LLC on behalf of American Association for Anatomy.)

Nanhsiungchelyidae are a group of large turtles that lived in Asia and North America during the Cretaceous. Here we report a new species of nanhsiungchelyid, Nanhsiungchelys yangi sp. nov., from the Upper Cretaceous of Nanxiong Basin, China. The specimen consists of a well-preserved skull and lower jaw, as well as the anterior parts of the carapace and plastron. The diagnostic features of Nanhsiungchelys include a large entire carapace length (∼55.5 cm), a network of sculptures consisting of pits and ridges on the surface of the skull and shell, shallow cheek emargination and temporal emargination, deep nuchal emargination, and a pair of anterolateral processes on the carapace. However, Nanhsiungchelys yangi differs from the other species of Nanhsiungchelys mainly in having a triangular-shaped snout (in dorsal view) and wide anterolateral processes on the carapace. Additionally, some other characteristics ( e.g. , the premaxilla is higher than wide, the maxilla is unseen in dorsal views, a small portion of the maxilla extends posterior and ventral of the orbit, and the parietal is bigger than the frontal) are strong evidence to distinguish Nanhsiungchelys yangi from Nanhsiungchelys wuchingensis . A phylogenetic analysis of nanhsiungchelyids places Nanhsiungchelys yangi and Nanhsiungchelys wuchingensis as sister taxa. Nanhsiungchelys yangi and some other nanhsiungchelyids bear distinct anterolateral processes on the carapace, which have not been reported in any extant turtles and may have played a role in protecting the head. The Nanxiong Basin was extremely hot during the Late Cretaceous, and so we suggest that nanhsiungchelyids might have immersed themselves in mud or water to avoid the heat, similar to some extant tortoises. If they were capable of swimming, our computer simulations of fluid flow suggest the anterolateral processes could have reduced drag during locomotion., Competing Interests: The authors declare there are no competing interests., (©2023 Ke et al.)

Background: Dinosaur eggs containing embryos are rare, limiting our understanding of dinosaur development. Recently, a clutch of subspherical dinosaur eggs was discovered while blasting for a construction project in the Upper Cretaceous red beds (Hekou Formation) of the Ganzhou Basin, Jiangxi Province, China. At least two of the eggs contain identifiable hadrosauroid embryos, described here for the first time., Results: The eggs, attributable to Spheroolithidae indet., are thin-walled and small (~ 660 mL) compared to those of Lambeosaurinae. The shape of the embryonic squamosal is reminiscent of that seen in the Late Cretaceous hadrosauroids Levnesovia transoxiana, Tanius sinensis, and Nanningosaurus dashiensis, suggestive of possible affinities., Conclusion: The small size of the eggs and embryos, similar to those of Hadrosaurinae, indicates that the larger eggs and hatchlings typical of Lambeosaurinae are evolutionarily derived., (© 2022. The Author(s).)

The predaceous beetle family Thanerocleridae is one of the smallest families of Cleroidea. It comprises only 36 extant species widespread on all continents. Three more species have been described from Cretaceous ambers of Myanmar and France. The fourth fossil representative of Thanerocleridae is described herein. Thanerosus antiquus gen. and sp. nov. is based on one fossil specimen preserved in an amber piece from Upper Cretaceous Kachin amber. The holotype was imaged using an X-ray micro-CT system to obtain high-quality 3D images. A phylogenetic analysis based on 33 morphological characters supports the placement of the new genus at the basal position in a tree of Thanerocleridae, in the vicinity of extant Zenodosus Wolcott and three extinct Mesozoic genera with which the new fossil shares open procoxal and mesocoxal cavities and transverse procoxae. We offer here a key to all extant and extinct genera in the family together with a complete list of all valid thaneroclerid taxa.

Here we report a new articulated skeleton of Yamaceratops dorngobiensis (MPC-D 100/553) from the Khugenetjavkhlant locality at the Shine Us Khudag (Javkhlant Formation, ?Santonian-Campanian) of the eastern Gobi Desert, Mongolia, which represents the first substantially complete skeleton and the first juvenile individual of this taxon. The specimen includes a nearly complete cranium and large portions of the vertebral column and appendicular skeleton. Its skull is about 2/3 the size of the holotype specimen, based on mandibular length. Its juvenile ontogenetic stage is confirmed by multiple indicators of skeletal and morphological immaturity known in ceratopsians, such as the long-grained surface texture on the long bones, the smooth external surface on the postorbital, open neurocentral sutures of all caudal vertebrae, a large orbit relative to the postorbital and jugal, the low angle of the lacrimal ventral ramus relative to the maxillary teeth row, narrow frontal, and straight ventral edge of the dentary. Osteohistological analysis of MPC-D 100/553 recovered three lines of arrested growth, implying around 3 years of age when it died, and verified this specimen's immature ontogenetic stage. The specimen adds a new autapomorphy of Yamaceratops , the anteroventral margin of the fungiform dorsal end of the lacrimal being excluded from the antorbital fossa. Furthermore, it shows a unique combination of diagnostic features of some other basal neoceratopsians: the ventrally hooked rostral bone as in Aquilops americanus and very tall middle caudal neural spines about or more than four times as high as the centrum as in Koreaceratops hwaseongensis , Montanoceratops cerorhynchus , and Protoceratops andrewsi . The jugal with the subtemporal ramus deeper than the suborbital ramus as in the holotype specimen is also shared with A. americanus , Liaoceratops yanzigouensis , and juvenile P. andrewsi . Adding 38 new scorings into the recent comprehensive data matrix of basal Neoceratopsia and taking into account the ontogenetically variable characters recovered Y. dorngobiensis as the sister taxon to Euceratopsia (Leptoceratopsidae plus Coronosauria). A second phylogenetic analysis with another matrix for Ceratopsia also supported this position. The new phylogenetic position of Y. dorngobiensis is important in ceratopsian evolution, as this taxon represents one of the basalmost neoceratopsians with a broad, thin frill and hyper-elongated middle caudal neural spines while still being bipedal., Competing Interests: The authors declare that they have no competing interests., (© 2022 Son et al.)

Borogovia gracilicrus is a small-bodied theropod dinosaur from the Maastrichtian (Upper Cretaceous) Nemegt Formation of southern Mongolia. The taxon is based on a single fragmentary specimen preserving only the distal part of the hindlimbs. The morphology of Borogovia shows a peculiar combination of features, some of which are traditionally considered troodontid synapomorphies and others which are unusual for Troodontidae but are shared with other maniraptoran clades. In particular, the second toe of B. gracilicrus differs from other troodontids in lacking some of the features which contribute to the specialized 'sickle-clawed' second toe, here termed the 'falciphoran condition', shared with dromaeosaurids and some other paravians, such as the strongly compressed and falciform ungual. Phylogeny reconstructions intended to explore the affinities of Borogovia consistently support its referral within a subclade of troodontids including all Late Cretaceous taxa. The placement of Borogovia is not significantly affected by its unusual combinations of hindlimb features or by the homoplasy of the elements forming the falciphoran condition. Borogovia is supported as a valid taxon and is distinct from the other Nemegt troodontids, Tochisaurus and Zanabazar . The lack of a falciform ungual, and the distinctive morphology of the second toe in B. gracilicrus are interpreted as a derived specialization among Troodontidae and not as retention of the plesiomorphic condition of non-paravian theropods., Competing Interests: The authors declare there are no competing interests., (©2021 Cau and Madzia.)

Turtle eggs containing embryos are exceedingly rare in the fossil record. Here, we provide the first description and taxonomic identification, to our knowledge, of a fossilized embryonic turtle preserved in an egg, a fossil recovered from the Upper Cretaceous Xiaguan Formation of Henan Province, China. The specimen is attributed to the Nanhsiungchelyidae (Pan-Trionychia), an extinct group of large terrestrial turtles (possibly the species Yuchelys nanyangensis ). The egg is rigid, spherical, and is one of the largest and thickest shelled Mesozoic turtle eggs known. Importantly, this specimen allowed identification of other nanhsiungchelyid egg clutches and comparison to those of Adocidae, as Nanhsiungchelyidae and Adocidae form the basal extinct clade Adocusia of the Pan-Trionychia (includes living soft-shelled turtles). Despite the differences in habitat adaptations, nanhsiungchelyids (terrestrial) and adocids (aquatic) shared several reproductive traits, including relatively thick eggshells, medium size clutches and relatively large eggs, which may be primitive for trionychoids (including Adocusia and Carrettochelyidae). The unusually thick calcareous eggshell of nanhsiungchelyids compared to those of all other turtles (including adocids) may be related to a nesting style adaptation to an extremely harsh environment.

The Upper Cretaceous (upper Cenomanian-middle Turonian) Akrabou Formation of Asfla, southeast Morocco is renowned for exceptionally preserved, often three-dimensional bony and cartilaginous fish fossils. Teleosts, rare holosteans and chondrichthyans are well known from the so-called 'Goulmima ichthyological assemblage', however pycnodonts (Actinopterygii, Pycnodontiformes) have received scant attention and remain undescribed until now. Five nominal species are recognised in the assemblage, including two new forms: Neomesturus asflaensis gen. et sp. nov. and Paranursallia cavini sp. nov. The Italian genus Polazzodus is reported in Morocco for the first time. Specimen taphonomy is examined in the context of substrate consistency and oxygenation of an outer shelf carbonate platform setting. Diversity and ecological disparity of the Goulmima assemblage is revised in regard to trophic partitioning with durophagy seemingly more diverse than previously recognised. Comparisons with other pycnodont-bearing horizons of similar age demonstrate strong faunal affinities between the Asfla pycnodonts and those in the western Tethys and South Atlantic., (© 2020 Elsevier Ltd. All rights reserved.)

Associated and isolated teeth of the extinct elasmobranch Ptychodus latissimus Agassiz, 1835 from the Upper Cretaceous Scaglia Rossa pelagic limestone of northern Italy are described and discussed here in detail for the first time. The dentition of this widely distributed species consists of low-crowned molariform teeth that exhibit marked and strong occlusal ornamentations suitable for crushing hard-shelled prey. The associated tooth sets and isolated teeth analyzed here are heterogeneous in size and crown outline, but unambiguously belong to a single species. Re-examination of this Italian material consisting of ca. 30 specimens mostly coming from historical collections allows for a rigorous assessment of the intraspecific variability of P. latissimus , including the identification of three different tooth "morphotypes" based on their positions within the jaws. The relatively flat crowns and occlusal sharp and thick ridges indicate a high adaptation for crushing hard-shelled prey in P. latissimus indicating that the durophagous adaptations of this species were certainly more pronounced than in all other species of Ptychodus . We hypothesize that P. latissimus was a third-level predator occupying habitats with abundant thick-shelled prey, such as inoceramid bivalves and ammonites., Competing Interests: The authors declare that they have no competing interests., (© 2020 Amadori et al.)

The first dinosaur embryos found inside megaloolithid eggs from Auca Mahuevo, Patagonia, were assigned to sauropod dinosaurs that lived approximately 80 million years ago. Discovered some 25 years ago, these considerably flattened specimens still remain the only unquestionable embryonic remains of a sauropod dinosaur providing an initial glimpse into titanosaurian in ovo ontogeny. Here we describe an almost intact embryonic skull, which indicates the early development of stereoscopic vision, and an unusual monocerotic face for a sauropod. The new fossil also reveals a neurovascular sensory system in the premaxilla and a partly calcified braincase, which potentially refines estimates of its prenatal stage. The embryo was found in an egg with thicker eggshell and a partly different geochemical signature than those from the egg-bearing layers described in Auca Mahuevo. The cranial bones are comparably ossified as in previously described specimens but differ in facial anatomy and size. The new specimen reveals significant heterochrony in cranial ossifications when compared with non-sauropod sauropodomorph embryos, and demonstrates that the specialized craniofacial morphology preceded the postnatal transformation of the skull anatomy in adults of related titanosaurians., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The fossil record of basal paravians in Gondwana is still poorly known, being limited to the Cretaceous unenlagiids from South America and the problematic Rahonavis from Madagascar. Here we report on a new paravian from the Cenomanian-Turonian (Late Cretaceous) of Río Negro province, NW Patagonia, Argentina. The new taxon exhibits a derived bird-like morphology of the forelimbs (e.g., robust ulna with prominent, anteriorly oriented, and proximally saddle-shaped radial cotyle and wide medial flange on metacarpal I) and a plesiomorphic foot with a raptorial pedal digit II. Phylogenetic analysis recovers the new taxon in a monophyletic clade with Rahonavis, being the sister group of the remaining Avialae and more derived than other non-avian dinosaurs. Both exhibit derived forelimb traits in opposition with their plesiomorphic hind limbs. The position of the new taxon and Rahonavis as stem avialans indicates that Gondwanan basal paravians are represented by two different clades, at least. The new taxon probably constitutes a previously unknown grade in the avian-line theropods in which some flight-related adaptations of the forelimbs are present in cursorial taxa. The present discovery sheds light on the acquisition of flight-related traits in non-avian dinosaurs and on the still poorly known paravian radiation in Gondwana.

Early endosymbiotic interactions are recorded only from a Cretaceous termite and a cockroach. Mesoblatta maxi Hinkelman, gen. et sp. nov. is the second representative of the dominant, cosmopolitan Mesozoic family Mesoblattinidae known from Cenomanian northern Myanmar amber, and the fourteenth from both amber and sedimentary rocks. Unique characters are rare (n = 19), symplesiomorphies are frequent (n = 140), and foremost is a standard maxillary palp, an irregular area between forewing veins radius and media, central ocellus, and multisegmented styli, suggesting an ancestral position with respect to Blattidae. Autapomorphies of this otherwise conservative taxon are only its large size and a short probasitarsus. Two nymphs with fecal pellets protruding from their body, Blattocoprolites mesoblattamaxi Hinkelman, ichogen. et ichnosp. nov., represent the first cockroaches with formalized coprolites (along with Blattocoprolites blattulidae Hinkelman, ichnosp. nov. established herein from Lebanese amber) and provide evidence of burial defecation. Subhomogenic consistency of coprolites with mucous components, "pseudoinclusions," leaf, trichia, wood debris, cycad pollen, endosymbiotic protists, and epibiotic bacteria directly document pollen transfer through the digestive tract and the earliest coevolution with protists and bacteria. Other post-burial fecal bacteria at the surface are documented for the first time in the Mesozoic, directly indicating structured dung processing. Reference samples (as well as almost all Myanmar amber samples) contain numerous "pseudoinclusions," probably representing damaged or dead cysts of Chlamydomonas hanublikanus Vršanská et Hinkelman, sp. nov. established on the basis of its reproductive stages (with an origin within the resin inside the tree). These are documented together with green algae, including Spirogyra Nees, 1820; flagellates; and flagellate amoebae, promoting massive future microbiota studies.

Two new genera and species of Coniopterygidae (Neuroptera) are described and illustrated from mid Cretaceous (Cenomanian) amber of Myanmar. Mulleroconishyalina gen. n. et sp. n. , attributed to the Coniopteryginae, bears a unique combination of venation characters and an abdomen without plicatures. The second new genus, attributed to the Aleuropteryginae, i.e. Palaeoconisazari gen. n. et sp. n. , displays a unique pattern of crossveins 1m-cua and 2mp2-cua, with the latter crossing the pigmented spot. A check-list of all fossil genera and species of Coniopterygidae is provided.

The vertebrate fauna of the Late Cretaceous Mussentuchit Member of the Cedar Mountain Formation has been studied for nearly three decades, yet the fossil-rich unit continues to produce new information about life in western North America approximately 97 million years ago. Here we report on the composition of the Cliffs of Insanity (COI) microvertebrate locality, a newly sampled site containing perhaps one of the densest concentrations of microvertebrate fossils yet discovered in the Mussentuchit Member. The COI locality preserves osteichthyan, lissamphibian, testudinatan, mesoeucrocodylian, dinosaurian, metatherian, and trace fossil remains and is among the most taxonomically rich microvertebrate localities in the Mussentuchit Member. To better refine taxonomic identifications of isolated theropod dinosaur teeth, we used quantitative analyses of taxonomically comprehensive databases of theropod tooth measurements, adding new data on theropod tooth morphodiversity in this poorly understood interval. We further provide the first descriptions of tyrannosauroid premaxillary teeth and document the earliest North American record of adocid remains, extending the appearance of this ancestrally Asian clade by 5 million years in western North America and supporting studies of pre-Cenomaninan Laurasian faunal exchange across Beringia. The overabundance of mesoeucrocodylian remains at the COI locality produces a comparatively low measure of relative biodiversity when compared to other microvertebrate sites in the Mussentuchit Member using both raw and subsampling methods. Much more microvertebrate research is necessary to understand the roles of changing ecology and taphonomy that may be linked to transgression of the Western Interior Seaway or microhabitat variation., Competing Interests: The authors declare that they have no competing interests.

Premise of the Study: Numerous fossils from the Upper Cretaceous have been confidently placed within modern crown groups. Many 95-75 Myr-old taxa, however, including the taxon described herein, do not fit well with known extant crown or stem groups. Understanding such fossils and their possible affinities would certainly enhance our understanding of the circumstances involved in a major eudicot radiation., Methods: Bulk samples from the Old Crossman Clay Pit were prepared using standard methodology, which includes several washing and sieving steps, and a treatment with hydrofluoric acid. The fossil taxon was coded into a matrix built from the combination of two previously published morphological matrices and was analyzed using the parsimony criterion with the computer program TNT., Key Results: The fossils have a unique combination of characters relative to living and fossil Ericales taxa, and therefore, a new genus, Teuschestanthes, is erected. Mosaic evolution and rapid parallel changes in such groups blur taxonomic distinctions, and these issues are exacerbated by limited numbers of characters available in fossils. Teuschestanthes flowers are slightly bilaterally symmetrical and somewhat variable with regard to petal disposition, suggesting an early stage in transition to bilaterality from radial symmetry early in eudicot history under pollinator selective pressure., Conclusions: While Teuschestanthes shares characters with modern Ericales and Sapindales, there are significant non-overlapping differences between Teuschestanthes and modern Sapindales (notably, among others, ovule number). Based on available evidence, however, the position of Teuschestanthes is likely as an early offshoot of the stem clade of core Ericales (Ericales sensu stricto). Its relatively unstable floral plan may presage subsequent bilaterality associated with growing selective pressure by advanced pollinators., (© 2018 Botanical Society of America.)

Premise of the Study: An inflorescence with three pistillate flowers in amber from the early Upper Cretaceous (Turonian, ~90-94 million years ago) of central New Jersey represents the oldest known flowers with features present in an early stem complex of the Fagales. The inflorescence has characteristics of Nothofagaceae, but also has strikingly distinct characters that suggest it is intermediate between Nothofagus and other Fagales. This intermediacy is consistent with its northern hemisphere distribution., Methods: We investigated this new fossil by comparing it with extant and fossil members of the Fagales using light microscopy and nano-computed tomography. In addition, for exploring its relationships, we mapped the morphological characters onto a widely accepted molecular-based tree of modern basal Fagales using standard methods of character optimization., Key Results: The phylogenetic position of the fossil inflorescence can be unequivocally determined by the presence of unique features, singly and in combination, that are found only in "basal" members of Fagales. The fossil adds critical information on the features of the early stem Fagales, evolution of the cupule in Nothofagaceae and Fagaceae, and a reasonable biogeographic hypothesis for the differentiation of southern (e.g., Nothofagaceae) and northern hemisphere Fagales., Conclusions: This new fossil provides insight into the early evolution of Fagales and suggests that early stem Fagales that had not yet differentiated into modern families were present in the Late Cretaceous of North America. Based on available evidence, the fossil is best interpreted as an early stem member of the Fagales, with features that suggest a transition from a more generalized Nothofagus-like fagalean ancestor with some unique presumably plesiomorphic features. The presence of an enlarged perianth and flexuous styles also suggests the possibility of insect pollination, which has been lost in all Fagales with the exception of some members of subfamily Castaneoideae in Fagaceae sensu stricto (which otherwise are very different from this fossil). The poorly developed, bract-like cupule valves of the fossil can be interpreted as primitive (i.e., incipient) or as reduced from more developed cupules that are found in most modern Fagaceae and Nothofagaceae., (© 2018 Botanical Society of America.)

We describe a new genus and species of Histeridae from Upper Cretaceous Burmese amber, Amplectister tenax Caterino & Maddison, gen. & sp. n. This species represents the third known Cretaceous histerid, which, like the others, is highly distinct and cannot easily be placed to subfamily. It exhibits prosternal characters in common with Saprininae, but other characters appear inconsistent with this possibility. The abdominal venter is strongly concave, and the hind legs are enlarged and modified for grasping. We hypothesize that this represents the earliest example in Histeridae of modifications for phoresy on social insects.

Teeth of iguanodontian ornithopods and ceratopsians could be remarkably similar, thus the referral of isolated dental material to particular neornithischian clades can be highly problematic. These groups are represented by the rhabdodontid Mochlodon vorosi and the basal coronosaurian Ajkaceratops kozmai in the Upper Cretaceous Csehbánya Formation at Iharkút (western Hungary). Whereas teeth of Mochlodon are common elements at the locality, no dental material belonging to Ajkaceratops was identified until now. Here we used mathematical statistical approaches, as well as tooth wear and dental microstructure analysis in order to decide whether the teeth previously referred to Mochlodon can be treated as a homogenous sample, or some remains belong rather to Ajkaceratops. According to our results, there was a striking morphological and structural convergence between the teeth of both taxa. However, the wear study revealed the existence of two different patterns within the sample. One is characterized by straight and parallel microstriations that suggest orthal movements during the jaw closure. This pattern was associated with Mochlodon. The other pattern appeared only on a few teeth, and it can be differentiated by its distinctive curved microstriations that indicate circumpalinal chewing. Because curved striations have never been described in ornithopods, but are found in several neoceratopsians, this pattern was associated here with Ajkaceratops. Here we present the first teeth that can provisionally be referred to the latter genus. We believe that the methodology discussed in this article will facilitate distinguishing ceratopsian and ornithopod teeth in other localities as well. Anat Rec, 300:1439-1463, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

A new parvicursorine alvarezsauroid theropod specimen IVPP V20341 from the Upper Cretaceous Wulansuhai Formation of Bayan Mandahu, Inner Mongolia, China is described. IVPP V20341 appears to be distinguishable amongst alvarezsauroids by possible cervical procoely and relatively larger semi-circular caudal neural canals, but these features are not proposed as autapomorphies because current knowledge of alvarezsauroid necks and tails remains sparse. IVPP V20341 is distinguishable from Linhenykus-the sole parvicursorine at Bayan Mandahu-by the location of the origination points of the anterior caudal transverse processes; in IVPP V20341 this is the anterodorsal corner of the centra, whereas in Linhenykus it is the posterior end of the prezygapophyses. A number of additional tentative differences between IVPP V20341 and Linhenykus are also identified, but cannot be confirmed until further details of anatomical variation along the neck and tail are revealed by future finds. Thus, following the study of IVPP V20341 there are still seven parvicursorine species from the Upper Cretaceous Gobi Basin, but future finds could increase this to eight species.

We report a new deltatheroidan mammal from the Upper Cretaceous of Henna, China. The new taxon, Lotheridium mengi, is based on a nearly complete skull and associated lower jaws with full adult dentition. Deltatheroidans are known mostly from fragmentary specimens from Asia and North America. Previous views on deltatheroidan relationships were diverse, but recent studies favored their metatherian affinity. The new specimen represents the most complete skull known for deltatheroidans and provides additional evidence that deltatheroidans already had the distinctive metatherian dental formula and replacement pattern and several other derived metatherian features, supporting the metatherian status for this clade. The new species also indicates that deltatheroidan mammals were more diverse and had broader geographical distributions than previously thought.

The trace fossil Lepidenteron lewesiensis (Mantell 1822) provides an exceptional taphonomic window to diversity of fishes as shown for the Upper Cretaceous of Poland, in the Middle Turonian-Lower Maastrichtian deposits of the Opole Trough, Miechów Trough, Mazury-Podlasie Homocline, and SE part of the Border Synclinorium. Lepidenteron lewesiensis is an unbranched burrow lined with small fish scales and bones, without a constructed wall. It contains scales, vertebrae, and bones of the head belonging to ten taxa of teleostean fishes: two undetermined teleosteans, six undetermined Clupeocephala, one Dercetidae, and one undetermined euteleostean. The preservation of fish remains suggests that fishes were pulled down into the burrow by an animal, probably by eunicid polychaetes.