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1.
Pentanogmius Taverne (Actinopterygii: Tselfatiiformes) is a Late Cretaceous bony fish. Here, the diagnosis for the genus is emended and a new species, P. fritschi sp. nov., described. The new species is based on a nearly complete skeleton from the Britton Formation (upper Cenomanian–lower Turonian) of the Eagle Ford Shale in Dallas County, Texas, USA. The skeleton measures about 1.7 m in total length and represents the sole Cenomanian–Turonian example of Pentanogmius in North America. The most peculiar aspect of this new species is the morphology of the dorsal fin in which its anterior one-third is elongate to form a ‘hook-shaped sail.’ Pentanogmius fritschi sp. nov. was likely an active swimmer in open ocean environments that possibly fed opportunistically on a variety of relatively small pelagic fishes and invertebrates. The present stratigraphic record and anatomical evidence indicate the following phylogenetic hypothesis among the three North American Pentanogmius species: [P. fritschi sp. nov. [P. evolutus + P. crieleyi]].  相似文献   

2.
Two new peculiar mid-Cretaceous braconid genera, Megalyrhyssalus gen. nov. (type species Megalyrhyssalus clavicornis sp. nov.) and Stephanorhyssalus gen. nov. (type species Stephanorhyssalus longiscapus sp. nov.), are described and illustrated from Burmese amber. According to the particular morphology and wing venation of Megalyrhyssalus gen. nov. a new subfamily Megalyrhyssalinae subfam. nov. is created. The subfamily Seneciobraconinae is synonymised under Protorhyssalinae (syn. nov.). Additionally, a key to the genera of Braconidae having second recurrent vein (2m-cu) in forewing is provided.  相似文献   

3.
The age of the marine Nodular Limestone Formation of the Bagh Group is refined at Substage level through ammonoid and inoceramid index taxa. The study is based on the fresh collections from three well-defined successive intervals (Lower Karondia, Upper Karondia and Chirakhan members) of this formation having excellent exposures in different localities of the Narmada Basin, central India. The first record of the widely distributed Turonian ammonoid genera Spathites Kummel and Decker and Collignoniceras Breistroffer from the Nodular Limestone Formation constrained its age exclusively to Turonian. The Early Turonian species Spathites (Jeanrogericeras) aff. revelieranus (Courtiller) and Mytiloides labiatus (Sclotheim) occur in the lower part, while the Middle Turonian marker Collignoniceras cf. carolinum (d’Obrbigny) and Inoceramus hobetsensis (Nagao and Matsumoto) occurs in the upper part of the Karondia Member. The record of the index species Inoceramus teshioensis (Nagao and Matsumoto) in association with Placenticeras mintoi Vredenburg from Chirakhan Member allows a definite Late Turonian age. The present contribution is an attempt to resolve the controversies in the age of the Nodular Limestone Formation and also demarcation of the three divisions (Early, Middle and Late) of the Turonian Stage in the Narmada Basin, central India.  相似文献   

4.
The Late Cretaceous (Turonian–Campanian) turritellid gastropod Roemerella Akopyan in Akopyan et al., 1990, is a junior homonym of the Devonian inarticulate brachiopod Roemerella Hall and Clarke, 1890. The generic name Roamerella nom. nov. is proposed for the homonymous gastropod.  相似文献   

5.
The Upper Cretaceous shallow-water carbonates of the Pyrenean Basin (NE Spain) host rich and diverse larger foraminiferal associations which witness the recovery of this group of protozoans after the dramatic extinction of the Cenomanian–Turonian boundary interval. In this paper a new, large discoidal porcelaneous foraminifer, Broeckina gassoensis sp. nov., is described from the middle Coniacian shallow-water deposits of the Collada Gassó Formation, in the Bóixols Thrust Sheet. This is the first complex porcelaneous larger foraminifer of the Late Cretaceous global community maturation cycle recorded in the Pyrenean bioprovince. It differs from the late Santonian–early Campanian B. dufrenoyi for its smaller size in A and B generations and the less developed endoskeleton, which shows short septula. Broeckina gassoensis sp. nov. has been widely employed as a stratigraphic marker in the regional geological literature, under the name of “Broeckina”, but its age was so far controversial. Its middle Coniacian age (lowermost part of the Peroniceras tridorsatum ammonite zone), established in this paper by strontium isotope stratigraphy, indicates that it took about 5 My after the Cenomanian–Turonian boundary crisis to re-evolve the complex test architecture of larger foraminifera, which is functional to their relation with photosymbiotic algae and K-strategy.  相似文献   

6.
Sclerogibbid wasps are obligate parasitoids of webspinners (Embiodea). Both groups have a particularly scarce geological record and are known since the Cretaceous: there are only four species of webspinners known from Burmese amber, and only two sclerogibbids were described from Barremian Lebanese and Cenomanian Burmese ambers. Here we report transferred genus from Aptian Choshi (Japan) amber and new sclerogibbids from Cenomanian Burmese and Charentese (France) ambers. The taxa described from Burmese amber are: Burmasclerogibba aptera gen. et sp. nov., Cretosclerogibba gen. nov. (with C. antennalis sp. nov., C. contractocollis sp. nov., C. neli sp. nov. and C. rasnitsyni sp. nov.) and Edrossia vetusta gen. et sp. nov. The first European fossil sclerogibbid Gallosclerogibba alnensis gen. et sp. nov. is described from Charentese amber. The holotype of Chosia yamadai Fujiyama, from Choshi amber, is re-described; it appears to be the oldest Laurasian sclerogibbid. The significant abundance and variety of Burmese sclerogibbid wasps (60% of fossil species known worldwide), as proxy of their hosts, were probably caused by the protection granted to them by the silk webs and possibly by the limited predation from ornithuromorph birds or crown-group ants. While all three extant sclerogibbid genera have apterous females, genera with winged females (Cretosclerogibba and Edrossia) dominated in Burmese amber. Small silk galleries from hosts may have favored the preservation of wings in females of Cretaceous sclerogibbids. Most new species described in the present paper, in addition to C. yamadai, are characterized by a very slender neck and a very long frontal process concealing the antennal toruli. These characters disappeared in extant species. We suggest that this loss was caused by a change in the fauna of predators, penalizing species with long neck and rostrum.  相似文献   

7.
The fossil snakefly family Baissopteridae from the Lower Cretaceous (upper Barremian) of the Yixian Formation of Liaoning Province, China is reviewed. Two genera and five species of Baissopteridae are recorded, including a new genus, namely Microbaissoptera gen. nov., and three new species, i.e., Baissoptera bicolor sp. nov., Baissoptera sinica sp. nov., and Microbaissoptera monosticha sp. nov. Moreover, Baissoptera euneura Ren, 1997 is herein treated as a new junior synonymy of Baissoptera grandis Ren in Ren et al., 1995. Baissoptera minima Ponomarenko, 1993 is transferred to the presently described new genus Microbaissoptera gen. nov. based on the small body-size and the presence of a single gradate series of crossveins in radial and medial areas of posterior part of both fore- and hind wings. A key to genera of Baissopteridae is provided.  相似文献   

8.
The paper presented is the first comprehensive, fully quantitative, high resolution study of marine palynology from an OAE3 black-shale environment. It is based on 175 m core spanning the upper Turonian to lower Santonian at Tarfaya, Morocco, NW Africa, which has been sampled from centimetre to 3 m intervals. The results are integrated and discussed with lithology and geochemistry data to (1) distinguish between potential changes in production and preservation of total organic carbon (TOC) accumulation and (2) constrain the stratigraphic position of the Oceanic Anoxic Event 3 (OAE3).The succession is characterized by increased total organic carbon (TOC), varying between 1% and 19% (average about 6%). Distinct black-shale horizons of variable thickness appear episodically throughout the succession, with higher frequency in the late Turonian. Higher TOC contents do not strictly correlate to lithologic black-shales or peaks of a specific taxon of organic-walled algae. The palynomorph spectrum is strongly dominated by organic-walled algae, with the ratio of terrigenous sporomorphs to organic-walled algae (t/m index) varying between zero and 0.05 (average 0.01). The dominance of algal organic matter is corroborated by the prevalence of Type I kerogen identified using Rock-Eval pyrolysis. Dinocyst diversity is low, with the absolute taxa number varying from 7 to 27 between single samples. The peridinioid/gonyaulacoid ratio of dinocysts (p/g ratio) shows strong fluctuations, varying between 1 and 283 (average of about 100).The upper Turonian interval is dominated by Bosedinia spp., a dinocyst taxon formerly described as abundant only in lacustrine sediments from the Oligocene and Miocene of SE Asia. This dominance is episodically modified by the increase of the warm-temperate waters dinocysts fraction, here mainly represented by the genera Alterbidinium, Isabelidinium and Spinidinium. Within the Coniacian-Santonian, black-shale horizons are limited in number and are concentrated within the upper Coniacian to lower Santonian interval. The dinocysts show alternating, prominent peak abundances of Palaeohystrichophora spp. and the warm-temperate water dinocysts fraction, here mainly represented by the genera Trithyrodinium and Chatangiella. However, a final episode of increased proportions of Bosedinia spp. is confined to a 5 m thick black-shale horizon closely spanning the Coniacian-Santonian boundary.Changes in the ratio of total sulphur to total organic carbon (TS/TOC) reflect fluctuating oxygen contents of bottom waters throughout the late Turonian to Santonian. These are significantly parallelled by the alternation of dinocysts assemblages suggestive of enhanced upwelling and water column stratification respectively, probably reflecting changes in the mode of TOC accumulation. Accordingly, preservation largely prevails during the late Turonian interval and changes towards increased production within the Coniacian-Santonian. However, a final preservation-event is probably represented by the black-shale horizon closely spanning the Coniacian-Santonian boundary (top Dicarinella concavata foraminifera zone), which may reflect an episodic shutdown of a major upwelling cell. It is thus proposed, that the “culmination” of the OAE3 at Tarfaya may represent intermittent preservation of TOC within an otherwise high productivity environment related to a global cooling trend.  相似文献   

9.
A new genus with two new species, Orentalphila gravia gen. et sp. nov. and O. caloa sp. nov., and three new species in two known genera, Sinosciophila angustia sp. nov., Sinosciophila seboa sp. nov. and Similsciophila undulata sp. nov., are described from the Lower Cretaceous of Yixian Formation at Huangbanjigou, Beipiao City, western Liaoning, China. These new taxa, representing the first records of mesosciophilids from this locality, provide morphological information and diversity for Mesosciophilidae in the Early Cretaceous. An updated key to known genera of Mesosciophilidae is provided. In addition, according the generic diagnosis revised by Zhang, 2007, Mesoplecia antiqua Hao and Ren, 2009 should be transferred to Mesosciophila Rohdendorf, 1946.  相似文献   

10.
11.
Eighteen echinoid species (seven regular and eleven irregular) belonging to twelve genera have been described from the Turonian-Santonian succession of two sections located in the northern part of Wadi Qena, Eastern Desert. The diversity of the recorded species is low in the Turonian (six species), but comparatively high in the Coniacian-Santonian (twelve species). Of the recorded species, Most of these species (72%) are recorded for the first time from Wadi Qena area, one left in open nomenclature, Mecaster sp., represents a new species, and two, Phymosoma microtuberculatum and Thylechinus (T.) said, represent new records for Egypt. The taxonomic rank of Parapygus sudrensis has been changed. Phymosoma microtuberculatum which is known from the ‘Senonian’ of southwest Europe is recorded herein in the lower Turonian. Two echinoid assemblage zones are recognizable in each of the studied two sections. They are correlated with other fossil assemblage zones in Egypt. Faunal affinity and paleobiogeography of the species are discussed. A new arrangement of apical disc plating in spatangoids is described and discussed.  相似文献   

12.
13.
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   

14.
Four new, monotypic genera of Aleyrodidae from the Lower Cretaceous Lebanese amber are described: Shapashe aithiopa gen. sp. nov.; Milqartis azari gen. sp. nov.; Aretsaya therina gen. sp. nov.; and Yamis libanotos gen. sp. nov. All new taxa represent subfamily Aleurodicinae. The key for identification of genera of Aleurodicinae from the Lebanese amber is provided. The morphological features of newly established taxa are discussed. The importance of the fossils for phylogenetic, evolutionary and ecological studies is presented.  相似文献   

15.
Three new genera and two new species, namely Burmodipteromantispa jiaxiaoae gen. et sp. nov., Mantispidipterella longissima gen. et sp. nov., and Jersimantispa gen. nov., respectively from the Cretaceous amber of Myanmar and New Jersey, are herein described in the lacewing family Dipteromantispidae, which is an enigmatic group by the mantispid-like appearance combined with strongly reduced, haltere-like hind wings. The male genitalia of Dipteromantispidae is described for the first time and provides new insight for understanding the familial phylogenetic position. A key to the dipteromantispid genera is also given.  相似文献   

16.
We re-define the Cretaceous bony fish genus Rhinconichthys by re-describing the type species, R. taylori, and defining two new species; R. purgatorensis sp. nov. from the lowermost Carlile Shale (middle Turonian), southeastern Colorado, United States, and R. uyenoi sp. nov. from the Mikasa Formation (Cenomanian), Middle Yezo Group, Hokkaido, Japan. Rhinconichthys purgatoirensis sp. nov. is designated on a newly discovered specimen consisting of a nearly complete skull with pectoral elements. Only known previously by two Cenomanian age specimens from England and Japan, the North American specimen significantly extends the geographic and stratigraphic range of Rhinconichthys. The skull of Rhinconichthys is elongate, including an expansive gill basket, and estimated maximum body length ranges between 2.0 and 2.7 m. Rhinconichthys was likely an obligate suspension-feeder due to its derived cranial morphology, characterized by a remarkably large and elongate hyomandibula. The hyomandibula mechanically acts as a lever to thrust the jaw articulation and hyoid arch both ventrally and anterolaterally during protraction, thus creating a massive buccal space to maximize filtering of planktonic prey items. Cladistic analysis supports a monophyly of suspension-feeding pachycormids including Rhinconichthys, but further resolution within this clade will require more information through additional fossil specimens.  相似文献   

17.
Two new genera with two new species in Berothidae, Maculaberotha nervosa gen. et sp. nov. and Magniberotha recurrens gen. et sp. nov., are described from Upper Cretaceous Myanmar (Burmese) amber. Based on the new specimens of the same species, we propose some venational characters as intraspecific variations, e.g., the markings on the wings and crossveins in the radial sector. We also study and compare the female genital sclerites from three genera of Haploberotha, Dasyberotha, and Jersiberotha to highlight the importance of using these characters preserved in amber for taxonomic and phylogenetic studies. Furthermore, an updated key to the berothid genera of Myanmar amber is provided.  相似文献   

18.
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   

19.
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   

20.
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   

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