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1.
The Kholokhovchan Flora comes from tuffaceous – terrigenous deposits of the Vetvinskaya Member (Chalbugchan Group) in the Penzhina and Oklan rivers interfluve, Northeastern Russia. The depositional environment of the plant-bearing deposits is interpreted to have been a freshwater lake. The Kholokhovchan Flora hosts 42 fossil plant species belonging to Marchantiopsida, Polypodiopsida, Ginkgoales, Leptostrobales, Bennettitales, Pinales and Magnoliopsida. It is characterised by diverse angiosperms, less diverse conifers and ferns, by the presence of relatively ancient Sphenobaiera, Phoenicopsis and Pterophyllum together with advanced Late Cretaceous Taxodium, Glyptostrobus and angiosperms, among which platanoids are quite diverse. The Kholokhovchan Flora is most similar to Penzhina and Kaivayam floras of the Anadyr-Koryak Subregion and Arman Flora of the Okhotsk-Chukotka volcanogenic belt (Northeastern Russia) and should be dated as Turonian–Coniacian. The Kholokhovchan Flora, that populated volcanic plateaus and intermontane valleys, are characterised by a mixture of ancient “Mesophytic” plants with typical Late Cretaceous “Cenophytic” taxa. This peculiar composition probably reflects a gradual penetration of new angiosperm-dominated plant assemblages into older floras: during the Late Cretaceous, “Cenophytic” assemblages migrated along river valleys and other disturbed habitats into the interior of Asia, eventually occupying volcanogenic uplands, and in places replacing the “Mesophytic” fern-gymnospermous communities that existed there. Two new angiosperm species, as well as four the most characteristic conifers of the Kholokhovchan Flora, are described: Cupressaceae gen. et sp. indet. cf. Widdringtonites sp., Taxodium cf. olrikii, Taxodium sp., Glyptostrobus sp., Ettingshausenia vetviensis sp. nov. and Parvileguminophyllum penzhinense sp. nov.  相似文献   

2.
Fossil snakes are relatively well represented in the Upper Cretaceous of northern Africa, with material known from Morocco, Sudan, Egypt, Libya, Algeria, and Niger. The Moroccan Kem Kem beds have yielded a particularly diverse snake assemblage, with Simoliophiidae, Madtsoiidae, ?Nigerophiidae and several unnamed taxa co-occurring. These fossils are important for our understanding of the early evolutionary history of snakes, and may shed light on the ecology and initial diversification of basal snakes. We describe a new taxon, Norisophis begaa gen. et sp. nov., from the Kem Kem beds of Begaa, in southeast Morocco. It is characterised by a marked interzygapophyseal constriction, parazygantral foramina, an incipient prezygapophyseal process, and an anterio-posteriorly short centrum. Several characteristics shared with Najash, Seismophis, Madtsoiidae, and Coniophis suggest that Norisophis is a stem ophidian. N. begaa further increases the diversity and disparity of snakes within the Kem Kem beds, supporting the hypothesis that Africa was a mid-Cretaceous hotspot for snake diversity.  相似文献   

3.
Diversity of palmately lobed leaves of angiosperms of the early–middle Albian floras of the Kolyma River Basin, the Omsukchan Coal Basin, Khabarovsk and Primorye Regions was studied. Leaf fossils, previously compared with those of genera Aralia, Sassafras and Lindera, now reassigned to the fossil genus Araliaephyllum. Four new combinations and one new species are published: A. kolymense (Kryshtofovich) Golovneva, comb. nov., A. luciferum (Kryshtofovich) Golovneva, comb. nov., A. ussuriense (Krassilov) Golovneva, comb. nov., A. ievlevii (Samylina) Golovneva, comb. nov., and A. popovii Golovneva, sp. nov. The type material has been restudied in detail, and lectotypes have been selected to all newly typified species. These species share many lauralean morphological and venation features. They represent the most likely early members of this group. This relationship is based on detailed study of the leaf architecture and comparison with other fossils with studied epidermal features. This study expands our knowledge of radiation and biogeography patterns of early angiosperms in northeastern Asia.  相似文献   

4.
The Albian Alexander Island macrofossil flora from the Antarctic Peninsula preserves a diverse community of liverworts (Marchantiophyta), ferns (Polypodiopsida), Lycopodiales, Equisetales, Cycadales, Ginkgoales, seed-ferns (Bennettitales and Pentoxylales), Coniferales, and the first representatives of angiospermous leaves in Antarctica. Despite the presence of angiosperms in this assemblage, ferns are the most diverse element of the flora and are also ecologically dominant, while angiosperms contribute a smaller component to floristic diversity and have low abundance. Here we describe 11 fern taxa from this assemblage. The fossils are assigned to Cladophlebis, Sphenopteris and two newly created genera. The new genera and species are described under Adiantitophyllum serratum gen. et. sp. nov. and Nunatakia alexanderensis gen. et. sp. nov., and the new species are recognized as Cladophlebis dissecta sp. nov., Cladophlebis drinnanii sp. nov., Cladophlebis macloughlinii sp. nov. and Sphenopteris sinuosa sp. nov. In total, there are 24 fern species known from Alexander Island. In comparison to older floras (Jurassic) there is a greater diversity of ferns, while latest Cretaceous floras preserve significantly fewer fern species and more angiosperms. Possible factors that might account for such high fern diversity are high rainfall or generally humid conditions, regular disturbances by flooding and occasionally fire, and the preservation of a diverse range of fern communities that represent several palaeoenvironments.  相似文献   

5.
A new species, Shoushida infera sp. nov. and a new genus with a new species, Stelepelecinus longus gen. et sp. nov., both in Pelecinidae, are described and illustrated. All specimens were collected from the Lower Cretaceous of Yixian Formation, Jehol Biota at Huangbanjigou, Beipiao City, western Liaoning Province, China. The forewing of Shoushida infera sp. nov. has a rudimentary “X” pattern, formed by veins of Rs, Rs1, Rs2 and 2r-rs, which is similar to but slightly different from that of Shoushida regilla Liu, Shih et Ren, 2009. Consistent with the phylogeny of Pelecinidae reported by Shih et al., 2010, this new species and S. regilla represent a transition between basal and crown pelecinids and the rudimentary “X” pattern evolved later to a more developed and robust “X” pattern in more derived pelecinids. In addition, the long petiole of the basalmost segment of metasoma, present in the male Stelepelecinus longus gen. et sp. nov., is documented for the first time, suggesting a likely Early Cretaceous origination of metasomal evolution leading to the thin and long petiole structure in the extant male Pelecinus thoracicus. We proposed two probable pathways of the transformation of the pelecinid male metasoma from the most plesiomorphic state to the more apomorphic states.  相似文献   

6.
A relatively diverse microbiota, preserved in-situ, has been discovered in cherty stratiform stromatolites of the middle Proterozoic Wumishan Formation (c. 1200–1300 Maold), Jixian Group, in the Ming Tombs area of Beijing. This microfossil assemblage consists of two parts: (1) the mat-building and mat-dwelling benthos which mostly belong to “long-lasting” taxa and are mostly common with those of other Proterozoic microbiotas; and (2) allochthonous elements including some plankton and peculiar structures which are either new forms first described here or taxa shared with some contemporaneous or penecontemporaneous microbiotas elsewhere. The latter may have more stratigraphic significance.Bivariate analysis on two characters measured (length and width) has been used in the classification of the elongate microfossils, and the results demonstrate that biometrical methods are effective in the taxonomy of some Precambrian microfossils.The following new taxa are described:Archaeoellipsoides obesus sp. nov., Archaeoellipsoides conjunctivus sp. nov., Bactrophycus oblongum gen. et sp. nov., Bactrophycus dolichum gen. et sp. nov., Callosicoccus crauros gen. et sp. nov.  相似文献   

7.
The byrrhid subfamily Lidryopinae subfam. nov. is proposed for Lidryops occultus gen. et sp. nov. described from Lower Cretaceous “opaque” amber originated from Archingeay-Les Nouillers, Charente-Maritime, southwest France which was studied using propagation phase contrast X-ray synchrotron microtomography at the European Synchrotron Radiation Facility (Grenoble). This byrrhid subfamily differs from members of the closely related groups (Chelonariidae, Limnichidae, Dryopidae, Elmidae, Lutrochidae) in the set of characters including the moderately convex dorsum, the subpectinate antennae, the five-segmented tarsi with strongly lobed tarsomeres 1–4, subsecuriform ultimate maxillary and labial palpomeres. An assumption on probable lifestyle of Lidryops occultus gen. et sp. nov. is proposed on the basis of structural peculiarities. A short review of the byrrhid fossil record and its analysis are made.  相似文献   

8.
Eight new genera and thirteen new species of lacewings (Neuroptera) are described from the Lower Cretaceous Wealden Supergroup, Weald Sub-basin: Principiala rudgwickensis sp. nov. (Ithonidae), Stenomylina medialis gen. et sp. nov., Protosmylina bifasciata gen. et sp. nov. (Osmylidae), Cretapsychops corami gen. et sp. nov., Micropsychops parallelus gen. et sp. nov., Valdipsychops logunovi gen. et sp. nov., V. brigidae gen. et sp. nov., V. maculosus gen. et sp. nov., V. proudlovei gen. et sp. nov., V. minimus gen. et sp. nov., Psychopsites rolandi gen. et sp. nov. (Psychopsidae), Actinophlebioides valdensis gen. et sp. nov. and Protohemerobius perexiguus gen. et sp. nov. (Neuroptera familia incertae sedis). Psychopsidae are shown to dominate the neuropteran fauna, while the presence of Brongniartiellidae has not been confirmed in the Wealden, due to previously thought representatives of this family being in fact psychopsids. This is the first fossil record of Ithonidae and Osmylidae in Britain. The range of Kalligrammatidae has been extended in the Cretaceous of Britain from the mid-Valanginian to early Barremian.  相似文献   

9.
On the basis of nine lithostratigraphical profiles, 23 cephalopods taxa (nautilus and ammonites) are described from the Preafrican Trough and the Kem Kem region. Among them, a new species is proposed: Spathites (Jeanrogericeras) asflaensis nov. sp. This fauna is placed in its biostratigraphical framework and correlated with the standard zonation of the late Cenomanian–early Turonian. Moreover, stratigraphic correlations are proposed for the whole Maghreb from the Tarfaya Basin in the west to central Tunisia in the east. Selected taxa reveal the paleogeographical context of the western Tethys; a complex distribution of emerged areas and epicontinental seas impacted by an important marine trangression that constantly modified the costaline.  相似文献   

10.
Eight new genera and 12 new species are described from the Lower Cretaceous Purbeck Limestone Group, southern England. Sophogramma wimbledoni sp. nov. (Kalligrammatidae) is described from the Purbeck of Wiltshire. Pterinoblattina peverilensis sp. nov., Pterinoblattina fasciata sp. nov., Purbepsychopsis parallela gen. et sp. nov. (Psychopsidae), Ovalorobius edmondsi gen. et sp. nov. (Prohemerobiidae), Mesosmylidus vulgaris gen. et sp. nov., Osmylochrysa anomala gen. et sp. nov., Osmylochrysa fragilis gen. et sp. nov., Stenochrysa gradata gen. et sp. nov. (Osmylidae), Mesypochrysa minuta sp. nov. (Chrysopidae), Purbemerobius medialis gen. et sp. nov. (?Hemerobiidae), Epimesoberotha parva gen. et sp. nov. (Berothidae) and Pseudocorydasialis alleni (Neuroptera familia incertae sedis) are described from Durlston Bay, Dorset. The species Pterinoblattina penna Scudder, Pterinoblattina pluma (Giebel) (Psychopsidae) Sialium sipylus (Nymphidae) and Osmylopsis duplicata (Osmylidae) are re-examined, described and figured. The genus Valdipsychops Jepson et al. has been synonymized with Pterinoblattina.  相似文献   

11.
The laminated marine mudstones of the Late Jurassic of Kimmeridge, southern England, yield two exceptionally well-preserved partial skeletons of a previously unrecognised species of early batoid. These are described as a new genus and species, Kimmerobatis etchesi gen. et sp. nov. which has a general “guitarfish” bauplan as in all other batoids known from the Jurassic. This species possesses a combination of primitive characters such as centra present within the majority of the synarcual and antorbital cartilages that fail to reach the pectoral skeleton along with more derived characters, such as the lack of fin spines. Until now, little study has been carried out on the affinities of Jurassic batoids, despite their key role in understanding batoid evolution. Results from parsimony and likelihood phylogenetic reconstruction indicates that the whole-bodied Jurassic batoids Spathobatis, Belemnobatis, and Kimmerobatis gen. nov. form their own clade, Spathobatidae, and do not lend support to a monophyletic “Rhinobatidae”. Among Jurassic batoids, Kimmerobatis gen. nov. is most derived, but with derived characters being independently acquired compared to modern batoids (e.g. presence of a postpelvic process). The inclusion of whole bodied Jurassic fossils have generated a more resolved hypothesis of batoid evolution throughout the Cretaceous and into the Cenozoic.  相似文献   

12.
The mid-Cenomanian fish beds of Nammoura, Mont-Liban district, Lebanon contain a diverse fauna of aquatic and terrestrial vertebrates, a few crustaceans and moderately well-preserved plant remains of which a single species,Sapindopsis anhouryi , was previously described by Dilcher & Basson (1990). We add 11 species of ferns, gymnosperms and angiosperms of which Nammouria cretacea gen. et sp. nov, Nupharanthus cretacea gen. et sp. nov., Sapindopsis libanensis sp. nov. and Nammourophyllum altingioides gen. et sp. nov. are new taxa. The florule differs markedly from both Early Cretaceous and Turonian plant assemblages of the Middle East, thereby representing a distinct stage of the regional floristic evolution. Its phytogeographic affinities are with contemporaneous floras of North America, Central Europe and the Crimea. A combination of such features as xeromorphism, the prevalence of compound leaves, and the presence of deciduous angiosperm components and gymnosperms may indicate climatic conditions similar to those of the present day Mediterranean.  相似文献   

13.
Four new genera and five new species of Archegocimicidae are described from the Lower Cretaceous of England: namely Mortalia martini gen. et sp. nov., Tyrion lannister gen. et sp. nov., T. cersei sp. nov., Stannis baratheon gen et sp. nov., Daenerys khaleesi gen. et sp. nov. A transitional position of the complex between Asian Late Jurassic and Early Cretaceous entomofaunas is indicated by this new material.  相似文献   

14.
Two new genera and three new species of the Mesozoic family Aeotheogrammatidae are described from the Lower Cretaceous of Yixian Formation (Liaoning Province, China): Cyclicogramma rotundum gen. et sp. nov. and Aetheogramma bistriatum sp. nov. from Huangbanjigou, and Curtogramma ovatum gen. et sp. nov. from Dawangzhangzi. The hind wing of Cyclicogramma rotundum gen. et sp. nov. differs from that of other species by its smaller size, its overall shape, RP bearing only two oblique radial branches, and its configurations of CuP, AA1, and AA2. Aetheogramma bistriatum sp. nov. is closely related to A. speciosum Ren and Engel, 2008, but distinguished from the latter by its distinctive configuration of RP1, and the narrower and longer AA2 space in the hind wing. Curtogramma ovatum gen. et sp. nov. is distinguished from all other species of the family by the forewing with M forking very far from the wing base.  相似文献   

15.
New plant macrofossil localities are found in the middle-upper part of the Albian Upper Hatira Formation of Makhtesh Qatan, an erosion crater in the northern Negev. These are so far the only outcrop localities in the Negev containing plant compressions and well-preserved sporomorphs. Their age assignments are controlled by the ammonite Knemiceras records below and above the plant-bearing sequence in the adjacent Makhtesh Hatira. The macrofossil assemblages are strikingly different in the sandy fluvial and shaly lacustrine facies, the former being dominated by Araucaria, Athrotaxopsis, Brachyphyllum and pinnatifid Sapindopsis, comparable at the plant assemblage and leaf morphological levels to the early to early late Albian assemblage of the North American Potomac flora. The lacustrine shale macrofossil assemblages appear archaic on account of their diverse pteridophyte component and sparse angiosperm remains. A new supposedly gnetophytic genus and species Qataniaria noae Krassilov, gen. et sp. nov. is dominant in the shale horizon. The sporomorph assemblages are strongly dominated by psilate trilete spores (87-93%). In the absence of elaterate forms, the angiosperm pollen Afropollis jardinus, Pennipollis, Tricolpites spp. and Walkeripollis sp. is consistent with the early Albian age. The abundance and diversity of conifers and the prominence of the fern bog assemblage suggest a relatively humid phase of the regional Albian climates.  相似文献   

16.
Our results present a taxonomic and palaeoecological study on non-marine gastropods from the latest Cretaceous to Paleocene deposits of the Pingyi Basin, Shandong Province, eastern China. These gastropods are systematically described: three species belonging to three genera including Physa dongtaiensis Gu, 1989, Hydrobia datangensis Yü, 1977, and the newly established species Cyathopoma pingyiensis sp. nov.; two indeterminata genera and species including Truncatelloidea gen. et sp. indet., and Pomatiopsidae gen. et sp. indet. Among them, Truncatelloidea gen. et sp. indet. and Cyathopoma pingyiensis sp. nov. are the dominant species with the longest record. Cyathopoma pingyiensis, sp. nov. is the earliest representative of this widely distributed Asian extant genus. Sedimentological facies analysis of the gastropod-bearing beds suggested that Truncatelloidea gen. et sp. indet. lived in a small pond with a river inlet and a shallow lake, while Ph. dongtaiensis, ?Pomatiopsidae gen. et sp. indet, and ?H. datangensis only thrived in the shallow lake. Cyathopoma pingyiensis sp. nov. inhabited the land area around the shallow lake. Our results showed that no significant species change of the gastropod fauna across the K/Pg (Cretaceous/Paleogene) boundary was observed in the Pingyi Basin.  相似文献   

17.
Four new Trichoptera species: Kliganigadukia taymyrensis gen. et sp. nov. (Hydrobiosidae), Archaeopolycentra yantardakh sp. nov. (Polycentropodidae), Taymyrodipseudon protopegasus gen. et sp. nov. (Dipseudopsidae), and Siberoclea parapolaria gen. et sp. nov. (Leptoceridae) from Late Cretaceous amber (Santonian, Kheta Formation, 85 Ma) of Taymyr (Siberia, Russian Federation) are described and illustrated. Data on the Cretaceous amber Trichoptera (13 families, 20 genera, 29 species) are summarized and discussed.  相似文献   

18.
Mesozoic leiodids are poorly known, and only one definitive leiodid is formally described from Burmese amber. Here we describe and illustrate the second definitive Mesozoic leiodid, Cretagyrtodes glabratus gen. et sp. nov., based on a single specimen from the Upper Cretaceous Burmese amber. The fossil is placed in Agyrtodini (subfamily Camiarinae) after maxillary palpomere 4 as wide as palpomere 3, and procoxal cavities closed behind. Cretagyrtodes is tentatively attributed to the extant “Eupelates group”. The discovery of Cretagyrtodes in Burmese amber suggests that the south hemisphere endemic tribe Agyrtodini is probably an ancient group, which has showed its first appearance before the breakup of Pangaea.  相似文献   

19.
In this study, we erect Sauroniops pachytholus gen. et sp. nov., a large-bodied theropod dinosaur from the Cenomanian (Upper Cretaceous) of Morocco, on the basis of an almost complete frontal showing a unique combination of features including a naso–frontal suture extended along 40% of the frontal length, a thick dome in the anterolateral corner of the dorsal surface, a trapezoidal prefrontal facet that is restricted to the anterodorsal margin of the lateral surface of the frontal with no participation in the orbital roof and separated from the lacrimal facet by a narrow vertical lamina, a hypertrophied ‘D-shaped’ lacrimal facet that is four times the anterior depth of the postorbital facet, and a raised posteromedial margin of the dorsal surface describing a saddle with the anterolateral dome and confluent with a series of anteromedial rugosities. Phylogenetic analysis found robust support for placing Sauroniops among the basal carcharodontosaurids and related to Eocarcharia, showed that some of the unusual features of the new theropod were convergently acquired by abelisaurids, and revealed a mosaic pattern in the evolution of the carcharodontosaurid skull table. The frontals of Sauroniops and Carcharodontosaurus, both from the ‘Kem Kem compound assemblage’ of Morocco, show comparable size but differ in the extent of the naso–frontal articulation, the shape and disposition of the prefrontal and lacrimal articulations, the development of dorsal ornamentation and the morphology of the supratemporal fossa. Among carcharodontosaurids, the skull table developed unique configurations among each lineage and appears diagnostic at the species-level. The dome-like frontal in Sauroniops may indicate head-butting behaviour in this taxon or evolved for visual display.  相似文献   

20.
The Huadu flora of Guangdong Province, South China contains the lepidodendrid Lepidodendron shanyangense Wu et He, its putative rhizophore Stigmaria cf. ficoides (Brongniart) Sternberg; sphenophyte s.l. Archaeocalamites scrobiculatus (Brongniart) Stur; bowmanitid Sphenophyllum tenerrimum (Ettingshausen) Stur; pteridophyll Sphenopteris sp. of uncertain taxonomic position; undetermined ferns gen. et sp. nov.; lyginopterid pteridosperm Rhodeopteridium hsianghsiangense (Sze) Zhang, Zhao et Wu, a trigonocarpoid pteridosperm represented by fronds and isolated pinnules of Paripteris gigantea (Sternberg) Gothan, male fructifications of Potoniea sp., and seeds of Trigonocarpus sp. Ecologically, the Early Carboniferous (Visean) Huadu vegetation was divided into two neighboring communities: (1) a near-shore hydrophilous "community A" with predominating Archaeocalamites and Rhodeopteridium; and (2) a wet forest "community B" with predominating shrubby trigonocarpalean pteridosperm Paripteris gigantea (Sternberg) Gothan and tall tree-like lepidodendrid Lepidodendron shanyangense Wu et He. The Huadu vegetation was physiognomically similar to present-day low-latitude mangrove forest.  相似文献   

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