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1.
Abstract: The edrioasteroid, Aragocystites belli gen. nov. sp. nov. from the middle Cambrian Murero Formation of Spain, is described based on a small number of very well‐preserved specimens. Important anatomical characteristics include star‐shaped and pseudoclavate theca, rare or absent epispires, well‐developed interradially positioned oral plates and several unorganized cover plates associated with each widely exposed flooring plate. A phylogenetic analysis including several Cambro–Ordovician species shows it is more derived than Stromatocystites and Totiglobus but is a sister group to a clade comprising Cambraster and Edriodiscus. Ontogenetic observations based on juveniles of 5 mm in diameter suggest that this species changed thecal shape markedly during growth. A. belli gen. nov. sp. nov. probably lived in quiet environments where it attached directly to the sea floor on stabilized substrates.  相似文献   

2.
Abstract: A new family, Pronemouridae fam. nov., with a new genus, Pronemoura gen. nov., and five new species of fossil stoneflies are described from Daohugou village (Middle Jurassic), Inner Mongolia, China: Pshii sp. nov., P. angustithorax sp. nov., P. longialata sp. nov., Pminuta sp. nov. and P. peculiaris sp. nov. Wing venation of pronemourinids presents some or considerable variety in the fore and hind wings of the same or different individuals. Pronemourinidae, retaining plesiomorphic characters (short, multisegmented cerci and CuA with forks), should be treated as the stem group of Nemouridae and Notonemouridae. Based on fossil data, we propose a model in which the extant plecopterid distribution began in the Early Cretaceous. Nemouridae and Notonemouridae must have occurred in Asia and begun to migrate from here by at least the Early Cretaceous.  相似文献   

3.
Discosorid and oncocerid cephalopods of the Kunda and Aseri Regional Stage (Darriwilian, Middle Ordovician) from Öland Island, Sweden and North Estonia are described for the first time. We demonstrate that a high generic and specific diversity of Oncocerida was already established in the earliest Darriwilian. The new oncocerid species Neumatoceras borense nov. sp., N. breviborense nov. sp., Paramiamoceras breviventrum nov. sp., Richardsonoceras gastroscopium nov. sp., R. gerhardi nov. sp., R. goldmanni nov. sp., R. haelluddenense nov. sp., Richardsonoceroides kingi nov. sp., R. oelandense nov. sp., and R. rhytium nov. sp. are erected; Richardsonoceroides schiefferdeckeri (Dewitz) is revised. The new graciloceratid Kundoceras evansi nov. gen., nov. sp. is erected. A review of records of early oncocerids from China shows that Richardsonoceras Foerste is probably the most primitive oncocerid and supports the hypothesis that oncocerids evolved in the early Floian or latest Tremadocian from a Bassleroceras Ulrich and Foerste-like ancestor. The new discosorid genus Paldoceras nov. gen. and species Paldoceras paldiskense nov. sp. and Pneptunsakerense nov. sp. are erected. These discosorids record the morphological link between the late Darriwilian Ruedemannoceras Flower and the early Floian Apocrinoceras Teichert and Glenister, which is considered to be the earliest discosorid.  相似文献   

4.
Abstract: Markuelia is a vermiform, annulated introvertan animal known as embryonic fossils from the Lower Cambrian to Lower Ordovician. Analysis of an expanded and revised dataset for Introverta shows that the precise position of Markuelia within this clade is dependent on the taxa included. As a result, Markuelia is assigned to the scalidophoran total group to reflect uncertainty as to whether it is a stem‐scalidophoran or a stem‐priapulid. The taxonomy of the genus is revised to provide an improved taxonomic framework for material assigned to Markuelia. Five species are recognized: M. secunda Val’kov, M. hunanensis Dong and Donoghue, M. lauriei Haug et al., M. spinulifera sp. nov. and M. waloszeki sp. nov. Finally, the preservation of Markuelia is evaluated in the light of both the taphonomy of the fossil embryos themselves and the experimental taphonomy of the priapulid Priapulus caudatus, which has been proposed as both a close relative and an anatomical analogue of Markuelia.  相似文献   

5.
Abstract: Palaeoscolecidan worms are rare, Early Palaeozoic fossils with uncertain affinities within the Ecdysozoa. They are locally abundant in the Cambrian and scattered in the Early Ordovician, but very sparse thereafter. Forty‐four specimens have been collected from the Middle Ordovician of the Builth‐Llandrindod Inlier of Mid Wales and include well‐preserved material assigned to seven new genera, with four additional species in open nomenclature. An additional specimen from the Arenig Pontyfenni Formation of South Wales is also described in open nomenclature. The total demonstrates much greater palaeoscolecid diversity than hitherto suspected for this time. The specimens are preserved as cuticle fragments in shales and siltstones, often of submillimetre size but in many cases with excellent preservation. The level of detail preserved in some is equal to that found in Cambrian phosphatized faunas. The new approach to collecting, and the recognition that this material can yield taxonomically useful information, opens new avenues for palaeoscolecidan research in siliciclastic environments. The new taxa are the following: Radnorscolex bwlchi gen. et sp. nov., Aggerscolex murchisoni gen. et sp. nov., Bullascolex inserere gen. et sp. nov., Wernia eximia gen. et sp. nov., Ulexiscolex ormrodi gen. et sp. nov., Pluoscolex linearis gen. et sp. nov. and Loriciscolex cuspidus gen. et sp. nov. The high diversity, and the taxonomic separation from known groups described primarily from Cambrian carbonates, implies that palaeoscolecidans either diversified significantly during the Ordovician or were taxonomically segregated between carbonate and siliciclastic settings. Palaeobiological findings also include confirmation that some palaeoscolecid basal cuticles were solid and others reticulate, plates (and platelets) could form by lateral accretion, plates were in part primarily phosphatic and in part organic and that in at least some groups, platelet secretion occurred external to plate secretion.  相似文献   

6.
Based upon COI‐5P, LSU rDNA, and rbcL sequence data and morphological characteristics, six new members of the noncalcified crustose genus of red algae Ethelia are described in a new family, Etheliaceae (Gigartinales), sister to the recently described Ptilocladiopsidaceae. The novel species are described from subtropical to tropical Atlantic and Indo‐Pacific Ocean basins; E. mucronata sp. nov. and E. denizotii sp. nov. from southern and northern Western Australia respectively, E. wilcei sp. nov. from the Cocos (Keeling) Islands of Australia, E. suluensis sp. nov. from the Philippines, E. umbricola sp. nov. from Bermuda and E. kraftii sp. nov. from Lord Howe Island, Australia. The generitype, Ethelia biradiata, originally reported from the Seychelles, Indian Ocean, is added to the Western Australian flora.  相似文献   

7.
Four new brachiopod species from the order Acrotretida (class Lingulata): Picnotreta saryarkensis sp. nov., Stilpnotreta propria sp. nov., Anabolotreta firma sp. nov., and Batenevotreta variabilis sp. nov. are described from the Agyrek Mountains, northeastern Central Kazakhstan from two olistoliths of limestones, which contain the uppermost Middle and lowermost Upper Cambrian fauna and are located in the Upper Ordovician olistostrome. These new species supplement the described earlier brachiopod assemblage from this region (Koneva and Ushatinskaya, 2008). Strong age and intraspecific variability of some Kazakh acrotretids is shown.  相似文献   

8.
Two new rhombiferan species Echinosphaerites mongolicus sp. nov. and Stichocystis altaicus sp. nov., described from a recently discovered Upper Ordovician locality in the Mongolian Altai, on the Chegertei River, suggest possible biogeographic links between this region and Gondwana and Baltica in the Ordovician. In the Upper Ordovician beds in the East Gobi Depression near Saishand Well, we identified the crinoid Ristnacrinus, previously recorded from the Ordovician of Estonia and Central Asia.  相似文献   

9.
Two new mammalian carnivoraform species, Uintacyon hookeri sp. nov. and Quercygale smithi sp. nov., are described from the early Eocene of Europe. U. hookeri sp. nov. is recorded in Mutigny (MP8 + 9, PE IV), Avenay (MP8 + 9, PE V), Brasles, Condé‐en‐Brie (MP8 + 9) and Cuis (MP 10), while Q. smithi sp. nov. comes from Mutigny and Mancy (MP10). Because the two species are not recorded in earliest Eocene localities such as Dormaal and Le Quesnoy (MP7, PE I), it is proposed that they dispersed after the main phase of the Mammal Dispersal Event. U. hookeri sp. nov. supports the existence of terrestrial connections with North America, while Q. smithi sp. nov. implies possible faunal exchange with Asia. This evidence for the evolution of the Carnivoraformes supports: (1) a rapid decrease in their diversity after the Mammal Dispersal Event; and (2) the existence of a mammal turnover event in Europe during the early Eocene. The discovery of a new species of Quercygale, which is generally considered as the closest carnivoraform to the crown‐group Carnivora, shows that the genus had already lost the M3 by the early Eocene and supports an important, but very poorly known, radiation of the carnivoraforms at least during the earliest early Eocene.  相似文献   

10.
Abstract: A diverse brachiopod fauna from a relatively deep water carbonate facies of the Upper Ordovician Beiguoshan Formation (uppermost Caradoc – lower Ashgill, middle Katian) is characterized by small shells and contains the oldest known Dicoelosia and Epitomyonia, two diagnostic taxa of deep water brachiopod palaeocommunities during the Late Ordovician and Silurian. Three new species are recognized: Dicoelosia cordiformis sp. nov., Dicoelosia perbrevis sp. nov. and Epitomyonia fui sp. nov. These pioneer forms of the family Dicoelosiidae show a relatively high degree of morphological plasticity. The shells of Dicoelosia from the Beiguoshan Formation range from the typical slender‐lobed form with a concavoconvex profile to the strongly equibiconvex, fat‐lobed morphotype that was not known previously until the late Silurian. The Beiguoshan dicoelosiids point to an important attribute of the deep water brachiopods: small generalists with high morphological plasticity, which make them ideal candidates as progenitors for the evolution of shallow water brachiopod faunas in shelf and platform depositional environments.  相似文献   

11.
Abstract: Several new taxa of snakeflies (Raphidioptera) are described from the Lower Cretaceous deposits of the Wealden, UK (Barremian), Montsec, Spain (Barremian) and the Crato Formation, Brazil (Aptian). Mesoraphidia ednae sp. nov. and M. hilli sp. nov. are described from the Wealden; Nanoraphidia lithographica sp. nov. and Iberoraphidia dividua gen. et sp. nov. are described from Montsec, and Baissoptera lisae sp. nov. is described from the Crato Formation. The geographical range of Nanoraphidia has potentially been extended.  相似文献   

12.
Erotini is a small tribe of net‐winged beetles known from the northern temperate zone. We investigated relationships and limits of tribes and genera using a molecular phylogeny inferred from rrnL, cox1 and nad5 mtDNA fragments. Lopheros Leconte, 1881 and Pseudaplatopterus Kleine, 1940 were inferred in current molecular analyses as terminal lineages within Erotini. Therefore, we consider Lopherotini Kazantsev, 2012 and Pseudaplatopterina Kazantsev, 2012 as junior synonyms of Erotini Leconte, 1881. The Platycis genus group comprises 19 species representing several genus‐group taxa previously placed in Platycis s. l. Konoplatycis Nakane, 1969 was recovered as a deeply rooted lineage of Erotini and we inferred another independent lineage for which we propose a new genus Sinoplatycis gen. nov. Additionally, we studied the diversity of Platycis s. l. in Asia, found their highest diversity in the temperate forest habitats of Eastern Asia and inferred the paraphyletic character of the subgenus Erotides s. str. Five new species are described from China: Sinoplatycis cardinalis sp. nov. , S. zhani sp. nov. (type species of Sinoplatycis gen. nov. ), Erotides brunnescens sp. nov. , E. pusillus sp. nov. and E. slipinskii sp. nov. The molecular phylogeny shows deep splits of Japanese species with respect to the continental Eurasian fauna and the role of shallow seas and mountain systems in the diversification of the Platycis genus group.  相似文献   

13.
Abstract: Groenlandibelus rosenkrantzi from the Maastrichtian of Greenland has long been thought to constitute an early representative of spirulid coleoids. This study shows that this view must be reassessed, at least in part. A re‐investigation of the types and of material recorded subsequently has revealed that none of these specimens is conspecific with the holotype of G. rosenkrantzi. Cyrtobelus birkelundae gen. nov, sp. nov. differs from the type of G. rosenkrantzi in having lower chambers and in lacking an apically elongated sheath. The longiconic phragmocone of G. rosenkrantzi has more features in common with the presumed spirulid genus Naefia. A specimen described in detail by J. A. Jeletzky in the mid 1960s as ‘G. rosenkrantzi’ is designated holotype of C. birkelundae sp. nov., which means that internal phragmocone features are still unknown in G. rosenkrantzi. Cyrtobelus hornbyense gen. nov, sp. nov. from the Campanian of western Canada constitutes the first record of early spirulids from the northeast Pacific, being based on seventeen extraordinarily well‐preserved phragmocones. This species differs from C. birkelundae sp. nov. only in the width of the siphuncular tube. The presence of a caecum, a nacre‐less conotheca that represents the continuation of the protoconch conotheca, conothecal flaps that anchor the mural parts of the septa, and a thin investment‐like sheath are characters shared only with Recent Spirula. In particular, the unusual protoconch architecture of Cyrtobelus gen. nov. challenges a phylogenetic origin within bactritoid‐like coleoids.  相似文献   

14.
Lobophora is a common tropical to temperate genus of brown algae found in a plethora of habitats including shallow and deep‐water coral reefs, rocky shores, mangroves, seagrass beds, and rhodoliths beds. Recent molecular studies have revealed that Lobophora species diversity has been severely underestimated. Current estimates of the species numbers range from 100 to 140 species with a suggested center of diversity in the Central Indo‐Pacific. This study used three molecular markers (cox3, rbcL, psbA), different single‐marker species delimitation methods (GMYC, ABGD, PTP), and morphological evidence to evaluate Lobophora species diversity in the Western Atlantic and the Eastern Pacific oceans. Cox3 provided the greatest number of primary species hypotheses(PSH), followed by rbcL and then psbA. GMYC species delimitation analysis was the most conservative across all three markers, followed by PTP, and then ABGD. The most informative diagnostic morphological characters were thallus thickness and number of cell layers in both the medulla and the dorsal/ventral cortices. Following a consensus approach, 14 distinct Lobophora species were identified in the Western Atlantic and five in the Eastern Pacific. Eight new species from these two oceans were herein described: L. adpressa sp. nov., L. cocoensis sp. nov., L. colombiana sp. nov., L. crispata sp. nov., L. delicata sp. nov., L. dispersa sp. nov., L. panamensis sp. nov., and L. tortugensis sp. nov. This study showed that the best approach to confidently identify Lobophora species is to analyze DNA sequences (preferably cox3 and rbcL) followed by comparative morphological and geographical assessment.  相似文献   

15.
Abstract: The fauna of false fairy wasps (Proctotrupomorpha: Bipetiolarida: Mymarommatoidea) occurring in Early Cretaceous (Albian) amber from north and north‐eastern Spain (Moraza, San Just, and El Soplao outcrops) is described. In total, 12 specimens have been recovered and four species recognized, all new: Alavaromma orchamum gen. nov. and sp. nov. (Alavarommatidae fam. nov.), Archaeromma hispanicum sp. nov. (Mymarommatidae), Galloromma alavaensis sp. nov., and G. turolensis sp. nov. (Gallorommatidae). The study indicates the necessity of revision and maybe fusion of both superfamilies, Mymarommatoidea and Serphitoidea, as the boundaries between them are less and less defined. However, major classificatory rearrangements must await the completion of the cladistic studies presently underway.  相似文献   

16.
Abstract:  Three new genera and four new species of the extinct mantidfly subfamily Mesomantispinae (Insecta: Neuroptera: Mantispidae) are described from the Lower Cretaceous Yixian Formation of Liaoning and the Middle Jurassic Jiulongshan Formation of Inner Mongolia: Archaeodrepanicus nuddsi gen. et sp. nov., A. acutus gen. et sp. nov., Sinomesomantispa microdentata gen. et sp. nov., (Yixian Formation) and Clavifemora rotundata gen. et sp. nov. (Jiulongshan Formation). The specimens described herein represent the first Mesozoic mantidfly compression fossils to have body parts preserved, including the specialized raptorial forelegs articulated to the prothorax anteriorly, an autapomorphy of the family. These new taxa further confirm the placement of the subfamily Mesomantispinae within the family Mantispidae; however, the monophyly of Mesomantispinae has not been confirmed, and it is likely that it will prove to be paraphyletic.  相似文献   

17.
This study documents previously unknown taxonomic and morphological diversity among early Palaeozoic crinoids. Based on highly complete, well preserved crown material, we describe two new genera from the Ordovician and Silurian of the Baltic region (Estonia) that provide insight into two major features of the geological history of crinoids: the early evolution of the flexible clade during the Great Ordovician Biodiversification Event (GOBE), and their diversification history surrounding the end‐Ordovician mass extinction. The unexpected occurrence of a highly derived sagenocrinid, Tintinnabulicrinus estoniensis gen. et. sp. nov., from Upper Ordovician (lower Katian) rocks of the Baltic palaeocontinent provides high‐resolution temporal, taxonomic and palaeobiogeographical constraints on the origin and early evolution of the Flexibilia. The Silurian (lower Rhuddanian, Llandovery) Paerticrinus arvosus gen. et sp. nov. is the oldest known Silurian crinoid from Baltica and thus provides the earliest Baltic record of crinoids following the aftermath of the end‐Ordovician mass extinction. A Bayesian ‘fossil tip‐dating’ analysis implementing the fossilized birth–death process and a relaxed morphological clock model suggests that flexibles evolved c. 3 million years prior to their oldest fossil record, potentially involving an ancestor–descendant relationship (via ‘budding’ cladogenesis or anagenesis) with the paraphyletic cladid Cupulocrinus. The sagenocrinid subclade rapidly diverged from ‘taxocrinid’ grade crinoids during the final stages of the GOBE, culminating in maximal diversity among Ordovician crinoid faunas on a global scale. Remarkably, diversification patterns indicate little taxonomic turnover among flexibles across the Late Ordovician mass extinction. However, the elimination of closely related clades may have helped pave the way for their subsequent Silurian diversification and increased ecological role in post‐Ordovician Palaeozoic marine communities. This study highlights the significance of studies reporting faunas from undersampled palaeogeographical regions for clade‐based phylogenetic studies and improving estimates of global biodiversity through geological time.  相似文献   

18.
Percolomonads (Heterolobosea) are aquatic heterotrophic flagellates frequently found in saline waters up to hypersaline environments. We isolated and cultivated seven strains of percolomonad flagellates from marine waters and sediments as well as from a hypersaline inland lake in the Atacama Desert. Morphological characterizations, comprising light and scanning electron microscopy, revealed only slight differences between the strains mainly limited to the cell shape, length of flagella, and length of the ventral feeding groove. Phylogenetic analyses of the 18S and 28S rDNA genes showed the formation of three fully supported clades within the Percolomonadida: the Percolomonadidae, the Barbeliidae fam. nov. and the Lulaidae fam. nov. We describe two new families (Barbeliidae fam. nov., Lulaidae fam. nov.), a new genus (Nonamonas gen. nov.), and five new species (Percolomonas adaptabilis sp. nov., Lula levis sp. nov., Barbelia pacifica sp. nov., Nonamonas montiensis gen. et sp. nov., Nonamonas santamariensis gen. et sp. nov.). Salinity experiments showed that P. adaptabilis sp. nov. from the Atlantic was better adapted to high salinities than all other investigated strains. Moreover, comparisons of our cultivation-based approach with environmental sequencing studies showed that P. adaptabilis sp. nov. seems to be globally distributed in marine surface waters while other species seem to be more locally restricted.  相似文献   

19.
简要记述了中国陕西省侧跗叶蜂属研究状况。描述了侧跗叶蜂属7新种:中原侧跗叶蜂 Siobla centralia Niu & Wei sp. nov.,弯毛侧跗叶蜂S.curvata Niu & Wei sp.nov.,S. listoni Niu & Wei sp. nov.,柔刃侧跗叶蜂S. pseudoplesia Niu & Wei sp. nov.,秦巴侧跗叶蜂S. qinba Niu & Wei sp. nov.,陕西侧跗叶蜂S.shaanxi Niu & Wei sp. nov.,狭颊侧跗叶蜂S. vulgaria Niu & Wei sp. nov.编制了陕西省26种侧跗叶蜂的分种检索表。  相似文献   

20.
Abstract: Four well‐preserved beetles, attributed to Eodromeinae within Trachypachidae, are described from the Mesozoic of Inner Mongolia, China. Eodromeus robustus sp. nov., E. daohugouensis sp. nov. and Unda chifengensis sp. nov. are from the Middle Jurassic of Daohugou. The diagnostic characters for the two genera are revised, and all species of these genera are keyed. A new genus and species, Sinodromeus liutiaogouensis gen. nov., sp. nov., is described from the Lower Cretaceous Yixian Formation of Liutiaogou. The current fossil records of Trachypachidae from China are reviewed, and only five species (four described here) can be convincingly attributed to this family. The morphological disparity of Mesozoic Eodromeinae suggests that they evolved a broad spectrum of locomotory lifestyles.  相似文献   

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