Early Cretaceous

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Zhonghe Zhou - One of the best experts on this subject based on the ideXlab platform.

  • spatiotemporal evolution of the jehol biota responses to the north china craton destruction in the Early Cretaceous
    Proceedings of the National Academy of Sciences of the United States of America, 2021
    Co-Authors: Zhonghe Zhou, Rixiang Zhu, Qingren Meng, Min Wang
    Abstract:

    The Early Cretaceous Jehol Biota is a terrestrial lagerstatte that contains exceptionally well-preserved fossils indicating the origin and Early evolution of Mesozoic life, such as birds, dinosaurs, pterosaurs, mammals, insects, and flowering plants. New geochronologic studies have further constrained the ages of the fossil-bearing beds, and recent investigations on Early Cretaceous tectonic settings have provided much new information for understanding the spatiotemporal distribution of the biota and dispersal pattern of its members. Notably, the occurrence of the Jehol Biota coincides with the initial and peak stages of the North China craton destruction in the Early Cretaceous, and thus the biotic evolution is related to the North China craton destruction. However, it remains largely unknown how the tectonic activities impacted the development of the Jehol Biota in northeast China and other contemporaneous biotas in neighboring areas in East and Central Asia. It is proposed that the Early Cretaceous rift basins migrated eastward in the northern margin of the North China craton and the Great Xing'an Range, and the migration is regarded to have resulted from eastward retreat of the subducting paleo-Pacific plate. The diachronous development of the rift basins led to the lateral variations of stratigraphic sequences and depositional environments, which in turn influenced the spatiotemporal evolution of the Jehol Biota. This study represents an effort to explore the linkage between terrestrial biota evolution and regional tectonics and how plate tectonics constrained the evolution of a terrestrial biota through various surface geological processes.

  • A bizarre Early Cretaceous enantiornithine bird with unique crural feathers and an ornithuromorph plough-shaped pygostyle.
    Nature communications, 2017
    Co-Authors: Min Wang, Jingmai K. O’connor, Yanhong Pan, Zhonghe Zhou
    Abstract:

    Enantiornithes are the most successful clade of Mesozoic birds. Here, we describe a new enantiornithine bird, Cruralispennia multidonta gen. et sp. nov., from the Protopteryx-horizon of the Early Cretaceous Huajiying Formation of China. Despite being among the oldest known enantiornithines, Cruralispennia displays derived morphologies that are unexpected at such an Early stage in the evolution of this clade. A plough-shaped pygostyle, like that of the Ornithuromorpha, evolved convergently in the Cruralispennia lineage, highlighting the homoplastic nature of Early avian evolution. The extremely slender coracoid morphology was previously unknown among Early Cretaceous enantiornithines but is common in Late Cretaceous taxa, indicating that by 131 million years ago this clade had already experienced considerable morphological differentiation. Cruralispennia preserves unusual crural feathers that are proximally wire-like with filamentous distal tips, a new morphotype previously unknown among fossil or modern feathers, further increasing the known diversity of primitive feather morphologies. Although now extinct, Enantiornithes was the most diverse group of birds in the Mesozoic. Here, Wang and colleagues describe a new species of enantiornithine bird from 131 million years ago with features that suggest extensive diversification had occurred in the enantiornithines by this time.

  • molecular evidence of keratin and melanosomes in feathers of the Early Cretaceous bird eoconfuciusornis
    Proceedings of the National Academy of Sciences of the United States of America, 2016
    Co-Authors: Yanhong Pan, Zhonghe Zhou, Min Wang, Wenxia Zheng, Alison E Moyer, Jingmai K Oconnor, Xiaoting Zheng, Xiaoli Wang, Elena R Schroeter, Mary H Schweitzer
    Abstract:

    Abstract Microbodies associated with feathers of both nonavian dinosaurs and Early birds were first identified as bacteria but have been reinterpreted as melanosomes. Whereas melanosomes in modern feathers are always surrounded by and embedded in keratin, melanosomes embedded in keratin in fossils has not been demonstrated. Here we provide multiple independent molecular analyses of both microbodies and the associated matrix recovered from feathers of a new specimen of the basal bird Eoconfuciusornis from the Early Cretaceous Jehol Biota of China. Our work represents the oldest ultrastructural and immunological recognition of avian beta-keratin from an Early Cretaceous (∼130-Ma) bird. We apply immunogold to identify protein epitopes at high resolution, by localizing antibody–antigen complexes to specific fossil ultrastructures. Retention of original keratinous proteins in the matrix surrounding electron-opaque microbodies supports their assignment as melanosomes and adds to the criteria employable to distinguish melanosomes from microbial bodies. Our work sheds new light on molecular preservation within normally labile tissues preserved in fossils.

  • a new basal ornithuromorph bird aves ornithothoraces from the Early Cretaceous of china with implication for morphology of Early ornithuromorpha
    Zoological Journal of the Linnean Society, 2016
    Co-Authors: Min Wang, Zhonghe Zhou, Shuang Zhou
    Abstract:

    Ornithuromorpha is the most derived avian group in the Early Cretaceous, advanced members of which encompass all living birds (Neornithes). Here we report on a new basal ornithuromorph bird, Bellulia rectusunguis gen. et sp. nov., represented by a nEarly complete skeleton from the Early Cretaceous Jehol Biota in northeastern China. A comprehensive phylogenetic analysis resolved the new taxon in a basal position that is only more derived than Archaeorhynchus and Jianchangornis among ornithuromorphs, increasing the morphological diversity of basal ornithuromorphs. The new specimen has a V-shaped furcula with a short hypocleidium, a feature otherwise known only in Schizooura among Cretaceous ornithuromorphs. We discuss the implications of the new taxon on the evolution of morphology of primitive ornithuromorphs, particularly of pectoral girdle, sternum and limb proportion pertaining to powered flight. The preserved gastroliths and pedal morphology indicate herbivory and lakeshore adaption for this new species. © 2015 The Linnean Society of London

  • fossil evidence of avian crops from the Early Cretaceous of china
    Proceedings of the National Academy of Sciences of the United States of America, 2011
    Co-Authors: Xiaoting Zheng, Zhonghe Zhou, Fucheng Zhang, Larry D Martin, David A Burnham, Desui Miao
    Abstract:

    The crop is characteristic of seed-eating birds today, yet little is known about its Early history despite remarkable discoveries of many Mesozoic seed-eating birds in the past decade. Here we report the discovery of some Early fossil evidence for the presence of a crop in birds. Two Early Cretaceous birds, the basal ornithurine Hongshanornis and a basal avian Sapeornis, demonstrate that an essentially modern avian digestive system formed Early in avian evolution. The discovery of a crop in two phylogenetically remote lineages of Early Cretaceous birds and its absence in most intervening forms indicates that it was independently acquired as a specialized seed-eating adaptation. Finally, the reduction or loss of teeth in the forms showing seed-filled crops suggests that granivory was possibly one of the factors that resulted in the reduction of teeth in Early birds.

Sunlin Chung - One of the best experts on this subject based on the ideXlab platform.

  • tectonic significance and geodynamic processes of large scale Early Cretaceous granitoid magmatic events in the southern great xing an range north china
    Tectonics, 2017
    Co-Authors: Simon A Wilde, Sunlin Chung, Tao Wang, Mei Fei Chu, Qianqian Guo
    Abstract:

    The origin and geodynamic evolution of peak Early Cretaceous magmatism in the southern Great Xing'an Range, North China, have long been controversial. Here we report new U-Pb zircon ages (141–129 Ma) of a suite of dioritic-granitic rocks from central Inner Mongolia, far from the sutures or plate boundaries of the Paleo-Pacific and Mongol-Okhotsk oceans, thus delineating an Early Cretaceous intracontinental magmatic province, which had a peak activity at 130–120 Ma. Dioritic suite including diorite, tonalite, and granodiorite shows variable zircon eHf(t) of +1.4 to + 11.8 and δ18O values of +5.7 to +6.9‰, while granitic suite consisting of monzogranite, syenogranite, and granite porphyry also records variable zircon eHf(t) of −0.9 to +15.0 and δ18O values of +6.3 to +8.1‰, suggesting crustal melting by preexisting crustal source with important recycled supracrustal components including fluids. Furthermore, these rocks show variable whole-rock δ7Li values (−0.6 to +12.1‰), indicating fluids played an important role in magma source. We propose a deep-sourced water-fluxed melting scenario by ancient hydrous slabs inherited from the Paleo-Asian Ocean that were trapped in the deep interior, thus releasing aqueous fluids to melt the lithospheric mantle and produce water-rich mafic magmas. These mafic magmas were underplated into crust where they promoted water-fluxed partial melting to generate the large-scale Early Cretaceous magmatism in the southern Great Xing'an Range. Such melting due to fluxing of aqueous fluids was probably operating as a widespread process responsible for the Early Cretaceous dramatically tectonomagmatic events and evolution of continental crust in NE Asia.

Peter R Crane - One of the best experts on this subject based on the ideXlab platform.

  • Early Cretaceous abietoid pinaceae from mongolia and the history of seed scale shedding
    American Journal of Botany, 2021
    Co-Authors: Fabiany Herrera, Peter R Crane, Gongle Shi, Niiden Ichinnorov, Andrew B Leslie, Maya A Bickner, Patrick S Herendeen
    Abstract:

    PREMISE Seed cones of extant Pinaceae exhibit two mechanisms of seed release. In "flexers" the cone scales remain attached to the central axis, while flexing and separating from each other to release the seeds. In "shedders" scales are shed from the axis, with the seeds either remaining attached to the scale or becoming detached. The Early fossil history of Pinaceae from the Jurassic to Early Cretaceous is dominated by flexing seed cones, while the systematic information provided by shedding fossil cones has been overlooked and rarely integrated with data based on compression and permineralized specimens. We describe the earliest and best-documented evidence of a "shedder" seed cone from the Aptian-Albian of Mongolia. METHODS Lignite samples from Tevshiin Govi locality were disaggregated in water, washed, and dried in air. Fossils were compared to material of extant Pinaceae using LM and CT scans. RESULTS Lepidocasus mellonae gen. et sp. nov. is characterized by a seed cone that disarticulated at maturity and shed obovate bract-scale complexes that have a distinctive ribbed surface and an abaxial surface covered with abundant trichomes. The ovuliferous scale has ca. 30-40 resin canals, but only scarce xylem near the attachment to the cone axis. Resin vesicles are present in the seed integument. Phylogenetic analysis places Lepidocasus as sister to extant Cedrus within the abietoid grade. CONCLUSIONS The exquisite preservation of the trichomes in L. mellonae raises questions about their potential ecological function in the cones of fossil and living Pinaceae. Lepidocasus mellonae also shows that a shedding dispersal syndrome, a feature that has often been overlooked, evolved Early in the history of Pinaceae during the Early Cretaceous.

  • geminispermum an Early Cretaceous Early middle albian cupulate unit from the angiosperm dominated puddledock flora of eastern north america
    Acta Palaeobotanica, 2019
    Co-Authors: Else Marie Friis, Peter R Crane, Kaj Raunsgaard Pedersen
    Abstract:

    A new genus and species, Geminispermum virginiense, is described based on a well-preserved coalified cupulate reproductive unit recovered from the Early Cretaceous (Early–middle Albian) Puddledock locality, Virginia, U.S.A. The reproductive unit is bisymmetrical and consists of an axis that bifurcates into two cupule-bearing stalks, each in the axil of a bract. Each cupule stalk bears a single non-valvate cupule recurved towards the center of the reproductive unit. The cupule opens distally by a short transverse slit with a distinct upper margin. Each cupule almost completely encloses a single orthotropous seed that is free from the cupule except at the base. The nucellus is also free from the integument except at the basal point of attachment. Geminispermum combines features of the ovulate structures of Caytoniales, Umkomasiales (= Corystospermales, including Doyleales) and Petriellales, but cannot be included in any of these existing orders as they are currently understood. The recurved, closed, non-valvate cupules are particularly similar to those of Caytonia, Petriellaea and Reymanownaea in external morphology, but differ in being one-seeded. The cupules of Geminispermum differ from the one-seeded cupules of Umkomasiales in being non-valvate and in having only a single cupule per bract. Geminispermum is perhaps most similar to the one- or two-seeded non-valvate cupules of Ktalenia from the Early Cretaceous of Argentina, but Ktalenia is poorly preserved, details of cupule architecture are uncertain, and the cupules appear to be associated with a single strongly dissected bract. Geminispermum is currently the only unequivocal seed plant cupule recovered from the Early Cretaceous Potomac Group and is distinct from all previously described cupulate reproductive structures.

  • diversity and homologies of corystosperm seed bearing structures from the Early Cretaceous of mongolia
    Journal of Systematic Palaeontology, 2019
    Co-Authors: Gongle Shi, Peter R Crane, Niiden Ichinnorov, Masamichi Takahashi, Patrick S Herendeen, Fabiany Herrera
    Abstract:

    New discoveries of corystosperm seed-bearing structures from the Tevshiin Govi locality, Mongolia, which is of Early Cretaceous (Aptian–Albian) age, show that the individual seed-bearing units of U...

  • extinct taxa of exotestal seeds close to austrobaileyales and nymphaeales from the Early Cretaceous of portugal
    Fossil Imprint, 2018
    Co-Authors: Else Marie Friis, Peter R Crane, Kaj Raunsgaard Pedersen
    Abstract:

    Early Cretaceous mesofossil floras from Portugal and North America include a surprising diversity of small, bitegmic angiosperm seeds with a hard exotestal seed coat. This study describes six diffe ...

  • new fossil pinaceae from the Early Cretaceous of mongolia1
    Botany, 2016
    Co-Authors: Fabiany Herrera, Peter R Crane, Gongle Shi, Niiden Ichinnorov, Masamichi Takahashi, Andrew B Leslie, Patrick Knopf, Patrick S Herendeen
    Abstract:

    Exceptionally well-preserved pinaceous leaves and seed cones are abundant in unconsolidated Early Cretaceous lignites in central Mongolia. These fossils include two seed cones, both of which have h...

Qianqian Guo - One of the best experts on this subject based on the ideXlab platform.

  • tectonic significance and geodynamic processes of large scale Early Cretaceous granitoid magmatic events in the southern great xing an range north china
    Tectonics, 2017
    Co-Authors: Simon A Wilde, Sunlin Chung, Tao Wang, Mei Fei Chu, Qianqian Guo
    Abstract:

    The origin and geodynamic evolution of peak Early Cretaceous magmatism in the southern Great Xing'an Range, North China, have long been controversial. Here we report new U-Pb zircon ages (141–129 Ma) of a suite of dioritic-granitic rocks from central Inner Mongolia, far from the sutures or plate boundaries of the Paleo-Pacific and Mongol-Okhotsk oceans, thus delineating an Early Cretaceous intracontinental magmatic province, which had a peak activity at 130–120 Ma. Dioritic suite including diorite, tonalite, and granodiorite shows variable zircon eHf(t) of +1.4 to + 11.8 and δ18O values of +5.7 to +6.9‰, while granitic suite consisting of monzogranite, syenogranite, and granite porphyry also records variable zircon eHf(t) of −0.9 to +15.0 and δ18O values of +6.3 to +8.1‰, suggesting crustal melting by preexisting crustal source with important recycled supracrustal components including fluids. Furthermore, these rocks show variable whole-rock δ7Li values (−0.6 to +12.1‰), indicating fluids played an important role in magma source. We propose a deep-sourced water-fluxed melting scenario by ancient hydrous slabs inherited from the Paleo-Asian Ocean that were trapped in the deep interior, thus releasing aqueous fluids to melt the lithospheric mantle and produce water-rich mafic magmas. These mafic magmas were underplated into crust where they promoted water-fluxed partial melting to generate the large-scale Early Cretaceous magmatism in the southern Great Xing'an Range. Such melting due to fluxing of aqueous fluids was probably operating as a widespread process responsible for the Early Cretaceous dramatically tectonomagmatic events and evolution of continental crust in NE Asia.

Michael S. Engel - One of the best experts on this subject based on the ideXlab platform.

  • morphologically specialized termite castes and advanced sociality in the Early Cretaceous
    Current Biology, 2016
    Co-Authors: Michael S. Engel, Phillip Barden, Mark L Riccio, David A Grimaldi
    Abstract:

    A hallmark of animals that are eusocial, or those with advanced sociality, is reproductive specialization into worker and queen castes. In the most derived societies, these divisions are essentially fixed and in some arthropods, include further specialization--a tripartite system with a soldier caste that defends the colony. Eusociality has originated numerous times among insects but is believed to have appeared first in the termites (Isoptera), in the Early Cretaceous. However, all termites known from the Cretaceous have, until now, only been winged reproductives (alates and dealates); the earliest soldiers and definitive workers were known from just the Miocene (ca. 17-20 million years ago [mya]). Here, we report six termite species preserved in Early Cretaceous (ca. 100 mya) amber from Myanmar, one described as Krishnatermes yoddha gen. et sp. nov., comprising the worker/pseudergate, winged reproductive, and soldier, and a second species, Gigantotermes rex gen. et sp. nov., based on one of the largest soldier termites yet known. Phylogenetic analysis indicates that Krishnatermes are in the basal "Meiatermes-grade" of Cretaceous termites. Workers/pseudergates of another four species are briefly described, but not named. One of these workers/pseudergates reveals that ants--the most serious enemies of modern termites--lived in close proximity to termites in the Burmese paleofauna. These discoveries demonstrate the Mesozoic antiquity of specialized termite caste systems and corroborate that among all social species, termites probably had the original societies.

  • an earwig insecta dermaptera in Early Cretaceous amber from spain
    Insect Systematics & Evolution, 2015
    Co-Authors: Michael S. Engel, David Peris, Stylianos Chatzimanolis, Xavier Delclòs
    Abstract:

    The order Dermaptera (earwigs) is recorded for the first time from the Early Cretaceous ambers of Spain. Autrigonoforceps ibericaEngel et Peris gen. et sp. n. is described and figured from a single, putative ♀ preserved in Albian amber from Penacerrada I. Due to its trimerous tarsi and the absence of ocelli, the placement of the new fossil within the Neodermaptera is clear. Although it seems close to Labiduridae, its confident placement in any family is impossible given the limited visibility of several critical characters. The species is compared with the labidurid Myrrholabiafrom mid-Cretaceous amber of Myanmar.

  • blood feeding true bugs in the Early Cretaceous
    Current Biology, 2014
    Co-Authors: Yunzhi Yao, Michael S. Engel, Xiaoting Zheng, Wanzhi Cai, Chungkun Shih, Yunyun Zhao, Dong Ren
    Abstract:

    Summary Blood-feeding insects, as vectors of disease for humans and livestock alike, have garnered significant interest [1, 2], but our understanding of their Early evolution is hindered by the scarcity of available material and the difficulty in distinguishing Early hematophages from non-blood-feeding relatives. Here, we report a new family of true bugs including two new genera and species from the Early Cretaceous Yixian Formation in Northeastern China. By utilizing geochemical methods for determining their diets and combining morphological and taphonomic data, we demonstrate that these new species represent the earliest evidence of blood feeding among true bugs, extending the geological record of such lineages by approximately 30 million years. Remarkably, one of the bugs appears to have perished immediately following a blood meal, which may have been from coexisting mammals, birds, or avian-related dinosaurs. These records expand the phylogenetic and ecological diversity of blood-feeding insects in the Early Cretaceous, enriching our knowledge of paleoecological associations in these ancient environments.

  • Bethylidae from Early Cretaceous Spanish Amber (Hymenoptera: Chrysidoidea)
    Journal of the Kansas Entomological Society, 2013
    Co-Authors: Jaime Ortega-blanco, Michael S. Engel
    Abstract:

    Abstract The diversity of bethylid wasps from Early Cretaceous (Albian) amber from Moraza (Alava amber, Spain) is presented. A total of eight specimens have been recorded from this outcrop and are assigned to the following taxa: Lancepyris alavaensis, new species; Liztor pilosus, new genus and species; and Cretepyris martini, new genus and species. Together this brings the total known fossil species of Bethylidae to 48. Unsurprisingly, given the antiquity of the taxa involved, placement in a living subfamily is difficult, especially for Cretepyris. The initial decision for its placement was doubtful between Bethylinae, for its more complete venation, and Epyrinae for the lack of clypeal mid-longitudinal carina or insertion, lack of propodeal anterior constriction, and lack of posterolateral spines (highlighting the doubts about the validity of Epyrinae as currently defined). However, the fossil subfamily Lancepyrinae was recently described from Lebanese amber, and the specimens from Spanish amber match al...

  • Early Cretaceous snakefly larvae in amber from lebanon myanmar and france raphidioptera
    American Museum Novitates, 2007
    Co-Authors: Vincent Perrichot, Michael S. Engel
    Abstract:

    Snakefly (Raphidioptera) larvae are newly documented from the Early Cretaceous ambers of Lebanon, Myanmar (Burma), and France. Previously only two Cretaceous larvae had been documented, one in Late Cretaceous (Turonian) amber from New Jersey and another in Early Cretaceous (Albian) amber from Myanmar. The specimens discussed herein are likely representative of the extinct family Mesoraphidiidae, but definitive familial assignment is currently not possible. The new fossil material is described and placed into context with the known larval morphology of modern and fossil species, as well as with the geological history of the order as documented by the remains of adults.