Lacustrine sediments of the Lower Cretaceous (lower Aptian) Xiagou Formation exposed near the village of Changma in the Changma Basin of northwestern Gansu Province, China have yielded more than 100 avian partial skeletons, many of which also preserve remnants of soft tissues such as feathers and skin. Collectively, these fossils characterize a rich avifauna dominated by the crownward ornithuromorph Gansus yumenensis Hou and Liu, 1984. Despite this wealth of Early Cretaceous bird material, no skeletal remains of other dinosaurs have been described from Changma to date. Here we report the first non-avian dinosaur body fossil from the Xiagou Formation of the Changma Basin. Consisting of an articulated left pectoral girdle and forelimb lacking the carpus and manus, the specimen pertains to a new dromaeosaurid theropod taxon, Jian changmaensis, gen. et sp. nov. Phylogenetic analysis recovers Jian within Microraptorinae, expanding the definitive fossil record of this clade to include northwestern China. The new Changma microraptorine constitutes an additional similarity between the theropod faunas of the Xiagou Formation of the Changma Basin and penecontemporaneous strata of the Jehol Group of northeastern China. In particular, the Changma theropod assemblage closely resembles that of the Sihedang locality of the Jehol Group in that both include representatives of Microraptorinae and are overwhelmingly dominated by single ornithuromorph taxa that phylogenetic analyses have repeatedly resolved as close relatives. This raises the possibility that the two sites were deposited under comparable paleoenvironmental settings that are otherwise poorly represented at known Jehol localities.

The Early Cretaceous avian ichnofauna of Laurasia, particularly in East Asia, is remarkably abundant. The northwestern region of China is the most productive area for bird tracks. Recently, four avian-dominated track sites have been discovered in the Cretaceous Lanzhou-Minhe Basin of Gansu, where the shorebird track Koreanaornis, , the ankylopollexian track Caririchinium and the turtle track Chelonipus occur. The Kongjiasi site yields a new type of the fluvio-lacustrine Chelonipus ichnocoenosis related to birds, which was previously defined to include only non-avian theropods and turtles. The site is associated with a waterfront foraging site of a Cretaceous shorebird which might be due to the invertebrate-rich substrate. The sole association of both bird and other theropod tracks with Chelonipus ichnocoenosis may indicate a difference in the appetite of avian and non-avian theropods for littoral foraging sites. And a review of the global turtle track-related ichnofauna and ichnocoenosis may offer new insights into the qualitative speculation of palaeobathymetry in riparian environments. (c) 2024 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

A variety of avemetatarsalian and non-archosaurian reptile tracks have been discovered in the lower Cretaceous Hekou Group in western China, where they occur alongside a herbivorous dinosaur skeletal fauna. A new track assemblage has recently been identified in the upper Hekou Group in Matan Natural Village, Jingyuan County, situated to the east of the primary track assemblage. The track-bearing bed is composed of sandstone-dominated, gypsum-included mottled clastic deposits, which indicate an arid braided river environment. All of the tracks in this site are classified as Cretaceous ichnospecies of Grallator, G. ssatoi, which are distributed in northern China. Additionally, the specimens exhibit members exceeding the original definition of Grallator (<= 15 cm). These well-preserved tracks not only demonstrate the widespread distribution of this ichnospecies in the Lower Cretaceous of China, but also provide insight into the relationship between the metatarsophalangeal pad traces of G. ssatoi and preservation. The sliding traces among them can indicate the ability of trackmakers to maintain balance while walking. Furthermore, the closely associated parallel trackways suggest that the trackmakers may have exhibited gregarious behaviour, and that such aggregation during marching may have been related to their self-preserving strategy.

The Lanzhou-Minhe Basin is a representative Early Cretaceous inland sedimentary basin in western China. Numerous Jurassic sauropod body fossils were collected in the Haishiwan area of Yongdeng, located along the northern margin of the basin. This study reports new theropod tracks from the Hongmensi tracksite in Yongdeng County, preserved on a fallen block of the Hekou Group. The assemblage comprises three trackways and at least 18 isolated tridactyl tracks, grouped into two morphotypes (similar to 12 and similar to 20 cm). Despite minor morphological variation, all tracks are most appropriately referred to Grallator cf. ssatoi. Track preservation varies across the ichnosurface, with flattened, shallow, and normally preserved examples reflecting differences in substrate consistency and mud layer thickness. These conditions produced marked morphological variation within a small area, highlighting the importance of preservation in ichnotaxonomic interpretation. The Hongmensi assemblage represents a composite grallatorid ichnoassociation comparable to those of the Tuchengzi Formation and other Hekou Group sites, underscoring both the consistency and size-structured nature of Early Cretaceous small theropod ichnofaunas in northern China.

Sauropod dinosaurs were gigantic quadrupedal herbivores. They range from Early Jurassic to Late Cretaceous and have been found on all continents. The rich sauropod faunas in the Middle and Late Jurassic of China are mainly from southern or western China. Here, we describe a non-neosauropod eusauropod from the Middle Jurassic Xinhe Formation of Gansu Province, northwestern China, based on an associated partial skeleton that includes a nearly complete skull with mandible, the five anteriormost cervical vertebrae appressed with the skull and the posterior 29 articulated caudal vertebrae. It can be diagnosed as a new taxon Jinchuanloong niedu gen. et sp. nov. based on several cranial and postcranial autapomorphies. In Jinchuanloong, the posterior margin of the external naris lies in front of the posterior margin of the antorbital fenestra, similar to that in basal eusauropods, and the base of the maxillary ascending process presents a foramen, similar to that in neosauropods. The finding of Jinchuanloong adds diversity and helps elucidate the evolution of the sauropods in East Asia.

Stegosaurs are a minor but iconic clade of ornithischian dinosaurs, yet due to a poor fossil record, their early evolution is poorly understood. Here, we describe a new stegosaur, Baiyinosaurus baojiensis, gen. et sp. nov. from the Middle Jurassic Wangjiashan Formation of the Pingchuan District, Baiyin City, Gansu Province, China. The frontal of Baiyinosaurus possesses a unique characteristic among Stegosauria: it is wider than long and contributes to both the medial and anterior margins of the supratemporal fenestra. The character combinations of dorsal vertebrae of Baiyinosaurus are also different to other stegosaurs: its neural arches are not greatly elongated, its parapophyses are well developed, and its neural spines are axially expanded in lateral. The features of the frontal and vertebrae of Baiyinosaurus are reminiscent of basally branching thyreophorans, indicating that Baiyinosaurus is transitional in morphology between early thyreophorans and early-diverging stegosaurs. Systematic analysis shows that Baiyinosaurus is an early-diverging stegosaur.

Stegosaurs are a minor but iconic clade of ornithischian dinosaurs, and along with their sister taxon ankylosaurs form the clade Eurypoda, the major radiation of Thyreophora (armoured dinosaurs). We here report some stegosaurian materials from the Lower Cretaceous Hekou Group of the Zhongpu area, Lanzhou-Minhe Basin, Gansu Province, China. Most of the morphology of the specimen is similar to Stegosaurus stenops and Stegosaurus homheni. However, its dorsal vertebrae have a higher neural arch and smaller neural canal than Stegosaurus stenops. The neural arches of the dorsal vertebrae of Stegosaurus homheni are deeply excavated dorsal to the neural canal in anterior view, which is not present in GSAU 201201. Because the material is fragmentary, we consider the new specimen as Stegosaurus sp. In phylogenetic analysis, it is also recovered as the sister taxon of Stegosaurus stenops. This is the first stegosaurian dinosaur from Gansu Province, which extends the geographical range of Stegosauria and enriches the Cretaceous stegosaurian record. The Ankylosaur Taohelong jinchengensis is also from the same area and same layer as this stegosaur, which is new evidence that they lived in the same ecosystems alongside each other. (c) 2024 Elsevier Ltd. All rights reserved.

The Istiodactylidae is one of three ornithocheiroid pterosaur lineages, characterised by a large nasoantorbital fenestrae and labiolingually compressed teeth. Their remains have been reported from Early Cretaceous rocks of northeastern China and Western Europe. A new istiodactylid pterosaur from the upper part of the Yixian Formation (Jingangshan Member) of the Jehol Group, distributed in western Liaoning Province and neighbouring areas, is described on the basis of an incomplete specimen including the partial skull, forelimb and hindlimb bones, and pelvis. This individual, here designated as a referred specimen of Nurhachius (Nurhachius sp.) is a skeletally almost mature pterosaur with an estimated wingspan of 1.6 m. This specimen is not only the geologically oldest known occurrence of Nurhachius, but also a new component of the pterosaur assemblage of the Jingangshan Member, and provides new information on the pelvis and hindlimb of istiodactylids and the palaeobiology of this clade. Considering previous reports of the istiodactylid remains and the geological ages of the strata that yielded them, it is suggested that different istiodactylids existed in Europe and China during the late Barremian.

Protorhyssalinae is an extinct, Cretaceous-only subfamily of braconid wasps hitherto comprising 7 genera and 7 species in its widest acceptance. A new genus Burmabracon gen. nov. with two new species, B. gracilens sp. nov. and B. grossus sp. nov. from the mid-Cretaceous Myanmar (Burmese) amber, are described and assigned to Protorhyssalinae, based on the following characters: head orthognathous and almost certainly cyclostome, antenna with more than 20 antennomeres, notauli complete, forewing with 2m-cu absent and hind wing with 1r-m and Cu present. The Mesozoic fossil record of the Braconidae suggests that the family originated in or before the Early Cretaceous.& nbsp; (c) 2021 Elsevier Ltd. All rights reserved.

The Early Cretaceous is characterized by warm background temperatures (i.e., greenhouse climate) and carbon cycle perturbations that are often marked by ocean anoxic events (OAEs) and associated shifts in the hydrologic cycle. Higher-resolution records of terrestrial and marine δ13C and δ18O (both carbonates and organics) suggest climate shifts during the Aptian–Albian, including a warm period associated with OAE 1a in the early Aptian and a subsequent “cold snap” near the Aptian–Albian boundary prior to the Kilian and OAE 1b. Understanding the continental system is an important factor in determining the triggers and feedbacks to these events. Here, we present new paleosol carbonate stable isotopic (δ13C, δ18O and Δ47) and CALMAG weathering parameter results from the Xiagou and Zhonggou formations (part of the Xinminpu Group in the Yujingzi Basin of NW China) spanning the Aptian–Albian. Published mean annual air temperature (MAAT) records of the Barremian–Albian from Asia are relatively cool with respect to the Early Cretaceous. However, these records are largely based on coupled δ18O measurements of dinosaur apatite phosphate (δ18Op) and carbonate (δ18Ocarb) and therefore rely on estimates of meteoric water δ18O (δ18Omw) from δ18Op. Significant shifts in the hydrologic cycle likely influenced δ18Omw in the region, complicating these MAAT estimates. Thus, temperature records independent of δ18Omw (e.g., clumped isotopes or Δ47) are desirable and required to confirm temperatures estimated with δ18Op and δ18Oc and to reliably determine regional shifts in δ18Omw. Primary carbonate material was identified using traditional petrography, cathodoluminescence inspection, and δ13C and δ18O subsampling. Our preliminary Δ47-based temperature reconstructions (record mean of 14.9 ∘C), which we interpret as likely being representative of MAAT, match prior estimates from similar paleolatitudes of Asian MAAT (average ∼ 15 ∘C) across the Aptian–Albian. This, supported by our estimated mean atmospheric paleo-pCO2 concentration of 396 ppmv, indicates relatively cooler midlatitude terrestrial climate. Additionally, our coupled δ18O and Δ47 records suggest shifts in the regional hydrologic cycle (i.e., ΔMAP, mean annual precipitation, and Δδ18Omw) that may track Aptian–Albian climate perturbations (i.e., a drying of Asian continental climate associated with the cool interval).

Three new species, Exilaulacus advenus sp. nov., Exilaulacus eximius sp. nov. and Electrofoenops exaltatus sp. nov. in two genera of Aulacidae, are described and figured based on three well-preserved specimens from the mid-Cretaceous Myanmar (Burmese) amber. Forewings of four described fossil species of Aulacidae and the three new species are studied by using the Geometric Morphometric Analyses (GMA) to further confirm their taxonomic classifications.

A total of 31 Lower Cretaceous tetrapod tracksites have been reported from four areas in Gansu Province, China: Yanguoshia, Guanshan, Zhongpu and Honggu. Here we report on the previously undescribed track types found at seven of these sites, five of which are sauropod dominated, with one site yielding ornithopod tracks and another one yielding theropod tracks. The Tianjiawan site is of particular significance for having produced the first lizard trackway from the Cretaceous of China and only the fourth global occurrence from this time period. The lizard trackway is tentatively assigned to ?Neosauroides ichnosp. indet., and compared with Neosauroides from the Cretaceous of Korea. As in Korea the Gansu lizard trackway occurs in lake margin sediments suitable for the preservation of the tracks of small tetrapods.

A new genus and species of Labenopimplinae (Ichneumonidae), Heteropimpla megista Li, Shih, Kopylov & Ren gen. et sp. nov., is erected based on a specimen in mid-Cretaceous Myanmar (Burmese) amber. A key to genera of Labenopimplinae is provided. In addition, a new species, Amplicella abbreviata Li, Shih, Kopylov & Ren (Tanychorinae) from the Lower Cretaceous Yixian Formation is described. Geometric morphometric analysis (GMA) was applied to study forewing venation of 24 Cretaceous species of Ichneumonidae and the results are presented for the first time. The GMA results not only confirm the taxonomic position of new taxa and relationships among these genera consistent with subfamily classifications, but also clarify the methodological differences between classical taxonomy and the GMA. http://zoobank.org/urn:lsid:zoobank.org:pub:DC98459D-45C1-4B78-B59E-F32787B787F1

The wasp family Panguidae Li, Rasnitsyn, Shih & Ren, 2019 was erected on the basis of the type species Pangu yuangu, which is a female preserved in mid-Cretaceous Burmese (Myanmar) amber. Herein, a new species, Pangu antiquum sp. nov., is described based on a male wasp. In addition, the wasp Prosphex anthophilos Grimaldi & Engel, 2019, described as Family Incertae sedis from Burmese amber, fits well with the diagnosis of Panguidae. We suggest to include Prosphex Grimaldi & Engel, 2019 as the second genus in the Panguidae. A key for genera and species of Panguidae is provided. Up to date, all taxa in Panguidae are known only from the mid-Cretaceous Burmese amber.

ABSTRACT Dinosaur and other tetrapod tracks are already known from multiple (~25) sites in the Early Cretaceous Hekou Group of Gansu Province. In addition to large sites (e.g. Yanguoxia) which have yielded more than 1500 tracks, small sites are important for verifying the distribution of morphotypes (ichnotaxa) over a wider region. Documentation of five newly-reported sites in the Honggu area supports previous studies which indicate a saurischian dominated (theropod and sauropod) ichnofauna with Asianopodus a common component of many assemblages. Ornithopod tracks also occur in several assemblages probably representing two morphotypes (Caririchium and Ornithopodichnus). One site reveals evidence of a small ornithopod progressing quadrupedally.

Fossils of Auroraceratops are abundant and found in high concentrations within the Mazongshan area of northwestern China. As small basal Neoceratopsia discovered from the Lower Cretaceous, its general anatomy is well known; however, the endocranial morphology of this genus has never been formally described before. Here, we selected a well-preserved skull which belongs to Auroraceratops sp. and used a high-resolution CT scan to reconstruct its three-dimensional, virtual endocast in order to illustrate the endocranial structures in detail. Our study provides the first description of the endocranial anatomy of Auroraceratops and compares it with other relevant ceratopsian taxa. Our result shows that for a basal Neoceratopsia, the endocranial morphology of Auroraceratops is closer to that of non-neoceratopsian ceratopsian Psittacosaurus than the more derived neoceratopsians, such as Pachyrhinosaurus, which provides new insight into the endocranial characters of basal Neoceratopsia.

Evaniidae, commonly called 'ensign wasps' or 'hatchet wasps', comprise more than 21 described extant genera with over 449 species and an additional 17 extinct genera including 35 species from the Cretaceous and Paleogene deposits. Herein, Burmaevania gen. nov. with two new species B. brevis sp. nov and B. aequalis sp. nov, and a new species of Newjersevania rasnitsyni sp. nov. are described based on three well-preserved specimens from the mid-Cretaceous Myanmar (Burmese) amber. Besides morphological comparisons, forewings of nine described genera of Evaniidae and the three new species are studied by using the Geometric Morphometric Analyses (GMA) to confirm their state. urn:Isid :zoobank.org:pub:DBE8E565-5671-4B5A-93F2-8AEC6DA22A50. (C) 2019 Elsevier Ltd. All rights reserved.

A new superfamily Panguoidea superfam. nov. is erected based on one new family, Panguidae fam. nov., with one new genus and species, Pangu yuangu gen. et sp. nov. In addition, one new species, Burmusculus magnus sp. nov. of Burmusculidae, is also described. Both of these two type specimens are from midCretaceous Myanmar (Burmese) amber. A key to species of Burmusculidae is provided. The new family Panguidae displays a contradictory array of features to further supplement the taxonomic and morphological characters of Apocrita. (urn:Isid:zoobank.org: pub:42BB16DA-1F8E-40F1-ADA9-0ECF321 B8355) (C) 2019 Elsevier Ltd. All rights reserved.

Li, L., Shih, C.K., Li, D. & Ren, D. 12 June 2019. New fossil species of Ephialtitidae and Baissidae (Hymenoptera, Apocrita) from the mid-Mesozoic of northeastern China. Alcheringa XX, X–X. ISSN 0311-5518. One new species of Ephialtitidae—Stephanogaster integra sp. nov.—from the uppermost Middle Jurassic Jiulongshan Formation at Daohugou Village, Inner Mongolia, China, and four new species of Baissidae—Manlaya proba sp. nov., Manlaya magna sp. nov., Manlaya ultima sp. nov. and Mesepipolaea parva sp. nov.—from the Lower Cretaceous Yixian Formation at Huangbanjigou Village, Liaoning, China, are described and illustrated. In addition, all described fossils of the genera Manlaya Rasnitsyn, 1980b and Stephanogaster Rasnitsyn, 1975 are listed with their distributions, geological ages, and key forewing characters. This list allows the comparison of interspecific venational differences within the two genera, which in turn highlights high levels of species-level diversity among both the Cretaceous species of Manlaya and Jurassic species of Stephanogaster. Longfeng Li* [fenger4499@163.com], Institute of Vertebrate Paleontology, College of Life Science and Technology, Gansu Agricultural University, Lanzhou, 730070, Gansu Province, PR China; Chungkun Shih [chungkun.shih@gmail.com], College of Life Sciences, Capital Normal University, Beijing 100048, PR China; Daqing Li [daqingli@gsau.edu.cn], Institute of Vertebrate Paleontology, College of Life Science and Technology, Gansu Agricultural University, Lanzhou City, 730070, Gansu Province, PR China; Dong Ren [rendong@mail.cnu.edu.cn], College of Life Sciences, Capital Normal University, Beijing 100048, PR China.