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1.
Complete, articulated starfish fossils are rare. However, more frequently encountered dissociated skeletal elements (ossicles) permit reliable taxonomic identification, making them a valuable data source for diversity estimates. Nearly 300 asteroid ossicles, collected from the middle Toarcian marls in western France can be assigned to five species. Four species and two genera are described: Comptoniaster vrinensis nov. sp. (Goniasteridae), Poncetaster crateri nov. gen. nov. sp. (Stauranderasteridae), Galbaster recurrans nov. gen. nov. sp. (Goniasteridae) and Pentasteria? liasica nov. sp. (Astropectinidae). The known diversity of Early Jurassic asteroids is increased from 12 to 16 species. These taxa illustrate the diversification of crown-group asteroids early in the Jurassic, following the Permo-Triassic crisis. They also reflect bias of the fossil record, and imply the existence of numerous ghost lineages in the evolutionary trees of extant groups. Variation in asteroid diversity across the “Seuil du Poitou” was driven by ecological constraints. The relative frequency (abundance of ossicles and diversity) of goniasterids and stauranderasterids increases in shallower environments. The Benthopectinidae, represented by Plesiastropecten hallovensis, occurred primarily from deep-shelf sediments. Similar ecological patterns are observed for more recent fossil and extant relatives, which further supports the idea of conservative evolution in post-Palaeozoic starfishes since the Early Jurassic.  相似文献   

2.
We describe the oldest Kalligrammatidae, two distantly related species of different subfamilies from the Lower Jurassic (lower Toarcian) of Germany: Liassopsychops curvatus Bode, 1953, sit. nov. (Liassopsychopinae n. subfam.) and Ophtalmogramma klopschari n. gen. n. sp. (Kallihemerobiinae). They lived in warm and relatively dry conditions. Subfamily Liassopsychopinae includes the Jurassic genera Liassopsychops and Huiyingogramma, sit. nov., which bear forewings characterized by Sc and RA not fused distally; MP, CuA, CuP, and A1 dichotomously branched; and a well-developed central eye-spot. The forewing of Ophtalmogramma n. gen. is most similar to that of Apochrysogramma Yang et al., 2011. The diversity of early Toarcian kalligrammatids indicates a late Triassic–earliest Jurassic origin of the family. A modified classification of the central eye-spots is proposed based on the presence/absence of four main components, i.e., the central pigmented disc (A), swellings (B), ocules (C), and outer rings (D). The function of the swellings is unclear, but they may have served as pheromone containers.  相似文献   

3.
A new glypheid lobster (Crustacea, Glypheidae), Glyphea pisuergae sp. nov. is described from the Early Jurassic (late Pliensbachian–early Toarcian) of Salinas de Pisuerga, Palencia, Spain. This species represents the second record for the genus in the Early Jurassic.  相似文献   

4.
A low-diversity Early Jurassic flora preserved in floodbasin siltstones of the Marburg Subgroup at Inverleigh Quarry in the Clarence-Moreton Basin, eastern Australia, is dominated by Allocladus helgei Jansson sp. nov., a conifer with denticulate leaves tentatively attributed to Araucariaceae. The assemblage also includes Rintoulia variabilis and Caytoniales, (Caytonia cucullata McLoughlin sp. nov. and cf. Sagenopteris nilssoniana), reinforcing the wide distribution of this order in Early to Middle Jurassic floras of Gondwana. Ferns (Cladophlebis and Sphenopteris species) and isoetalean lycophytes (Isoetites sp.) constitute the herbaceous elements of the flora. The palynoflora is dominated by cheirolepidiacean (Classopollis) pollen and is attributable to the upper part of the Corollina (= Classopollis) torosa Zone of late Pliensbachian–early Toarcian age (180–185 Ma). The Inverleigh flora represents one of the few Australian assemblages dated between the major phases of floristic turnover at the end of the Triassic and the Toarcian. Sedimentological characteristics, cuticular features of the conifer leaves and the abundance of free-sporing plants indicate a relatively humid palaeoclimate for the Clarence-Moreton Basin Early Jurassic.  相似文献   

5.
One new genus and five new species of dragonflies (Odonata) are described and figured from the Yixian Formation of northeastern China, viz. two gomphaeschnids Sinojoria magna nov. sp. and S. cancellosa nov. sp., plus three progobiaeshnids Mongoliaeshna hadrens nov. sp., M. exiguusens nov. sp., and Decoraeshna preciosus nov. gen., nov. sp. These new discoveries confirm the apparently sudden great diversification in China of the clade Aeshnoptera during the Middle-Upper Jurassic, together with the Upper Mesozoic to modern lineages of dragonflies. At the same time, some ‘ancient’ groups of Odonata became extinct.  相似文献   

6.
Abstract: We describe an almost complete ichthyosaur skeleton from the middle Toarcian (Lower Jurassic) of the Beaujolais foothills near Lyon, France, and assign it to Temnodontosaurus azerguensis sp. nov. This new species exhibits cranial peculiarities such as a thin, elongated and possibly edentulous rostrum, as well as a reduced quadrate. These characters indicate dietary preferences that markedly differ from other species referred to Temnodontosaurus, a genus previously considered as the top predator of the Early Jurassic seas. Despite a conservative postcranial skeleton, we propose that Temnodontosaurus is one of the most ecologically disparate genera of ichthyosaurs, including apex predators and now a soft prey longirostrine hunter. Ammonites collected from the same stratigraphic level as the described specimen indicate that the new species is somewhat younger (bifrons ammonite zone) than the most known Toarcian ichthyosaurs and therefore slightly postdates the interval of severe environmental changes and marine invertebrate extinctions known as the Toarcian Oceanic Anoxic Event. The present study therefore raises the question of whether postcrisis recovery of vertebrate faunas, including the radiation of Temnodontosaurus into a new ecological niche, may have been a consequence of marine ecosystem reorganization across this event.  相似文献   

7.
Three new genera and five new species of osmylid lacewings are described from the locality Karatau (Kazakhstan, Upper Jurassic): Jurosmylus parvulus sp. nov. (Protosmylinae), Ensiosmylus acutus gen. et sp. nov. (Spilosmylinae), Kolbasinella elongata gen. et sp. nov. (Gumillinae), Arbusella bella gen. et sp. nov. and Jurakempynus arcanus sp. nov. (Kempyninae). Another new osmylid species (Jurakempynus sublimis sp. nov.) is described from the Upper Jurassic of Mongolia (Shar-Teg locality). The quantitative compositions of the osmylid faunas of Karatau and Shar-Teg are discussed.  相似文献   

8.
Three new species of Tettigarctidae from the Middle Jurassic of Daohugou, China are described: Shuraboprosbole daohugouensis nov. sp., S. minuta nov. sp., and S. media nov. sp. The revised diagnostic characters of Shuraboprosbole Becker-Migdisova are provided based on well-preserved whole-bodied fossil tettigarctids. So far, only four definitive species of Tettigarctidae are recorded from the Mesozoic of China. The pronotum concealing major of mesonotum seems to be an autapomorphy of Tettigarctinae. The “cicadellid-like tarsi” found in Cicadellidae and Brazilian Tettigarctidae are probably a parallel evolution.  相似文献   

9.
The new species Protorhyphus rohdendorfi sp. nov. (Protorhyphidae), Mesorhyphus handlirschi sp. nov., and M. hennigi sp. nov. (Anisopodidae), Procramptonomyia ponomarenkoi sp. nov. and P. kovalevi sp. nov. (Procramptonomyiidae) are described from the Upper Jurassic deposits of Mongolia (Shar Teg); some features of Archirhyphus asiaticus Rohdendorf, 1964 are revealed. The latter two species are also known from the locality of Karatau (Kazakhstan, J2/3). The genus Tega Blagoderov, Krzemi??ska, and Krzemi??ski, 1993 is transferred from the family Cramptonomyiidae into Anisopodidae (Teginae subfam. nov.).  相似文献   

10.
Four new species of mayfly nymphs, Furvoneta relicta sp. nov., Clavineta eximia sp. nov. (originally Mesoneta antiqua), Mesobaetis latifilamentacea sp. nov., and Stackelbergisca cylindrata sp. nov. are described from the Jurassic of China. All these species may have inhabited lakes rather than flowing water. The geological age and stratigraphical correlation of the nymph-bearing strata are briefly reviewed.  相似文献   

11.
Grammoceratinae (Hildoceratidae, Ammonitina) abound in the Toarcian strata of many western Tethyan localities, especially the Subbetic and Lusitanian basins (of southern Spain and central western Portugal, respectively). They decline through the Aalenian and disappear by the lowermost Bajocian. The genera Asthenoceras, Vacekia (subgenera Vacekia and Nadorites) and Fontannesia are traditionally considered as the last Grammoceratinae, with species of Osperleioceras occurring in the uppermost Toarcian. Grammoceratinae are common in the eastern Pacific, especially Oregon and Alaska where Asthenoceras is abundant. They also occur in the eastern Tethys (Thailand). Although studies of Toarcian to early Bajocian Subbetic and Lusitanian grammoceratins already exist, new material from these and other palaeogeographic areas (England, Portugal and Spain) is revised here. A new genus, Linaresites nov. gen. (for Fontannesia montillanensis Linares and Sandoval) and two new species (Vacekia striata Henriques, and Asthenoceras taverai Sandoval) are described. Another form, “Asthenoceras” sp. A is described and let in open nomenclature. Temporal analysis of Aalenian to early Bajocian Grammoceratinae demonstrates a progressively more evolute morphology through time, sometimes coupled with size reduction. Palaeogeographic evidence suggests that during the early Middle Jurassic, western Tethys and eastern Pacific were temporarily well connected, possibly through the Hispanic Corridor, as demonstrated by the similarity between Tethyan and eastern Pacific Grammoceratinae.  相似文献   

12.
A lacewing assemblage from the Middle Jurassic of the West Siberian Kubekovo locality, the only know Jurassic lacewing fauna of Russia, is discussed. One new genus and two new species of Osmylidae from Kubekovo, Kubekius multiramosus gen. et sp. nov. and Epiosmylus longus sp. nov. are described. Thaumatomerobius mirabilis Ponomarenko, 1985 is transferred to the family Saucrosmylidae, which has only been recorded in the Middle Jurassic of Daohugou.  相似文献   

13.
Three new species of the snipe fly genus Protorhagio, viz. P. karataviensis sp. nov., P. ponomarenkoi sp. nov., and P. ruptus sp. nov., are described from the Middle-Upper Jurassic Karabastau Formation in Kazakhstan. The type species of the genus, P. capitatus, is redescribed. A key is provided to all known species of Protorhagio.  相似文献   

14.
Three new species of fossil snipe flies (Insecta, Diptera, Rhagionidae) from the Daohugou Formation of Chifeng City in Nei Monggol Autonomous Region (= Inner Mongolia), northeastern China are described as Palaeobolbomyia sinica nov. sp., Ussatchovia robusta nov. sp. and Ussatchovia gracilenta nov. sp. They represent the first records of the genera Palaeobolbomyia Kovalev and Ussatchovia Kovalev in China and have implications for stratigraphic correlation of the formations in which they are found. Although the precise age of the Daohugou Formation is currently unresolved, it is most likely Callovian-Oxfordian (latest Middle Jurassic-earliest Late Jurassic) rather than early Middle Jurassic (late Aalenian-early Bajocian) or Early Cretaceous.  相似文献   

15.
Abstract

Teleosauroids were a clade of semi-marine crocodylomorphs that attained near-global distribution during the Jurassic Period. They were particularly common during the Toarcian (Early Jurassic) and are well documented throughout the UK and Germany. However, Toarcian teleosauroids discovered in Luxembourg have been little studied and rarely discussed in the scientific literature. Here we present a comprehensive catalogue of Luxembourg thalattosuchian specimens, including nine teleosauroids (all from the Toarcian) and five Thalattosuchia indeterminate (four from the Toarcian and one from the Bajocian), many of which are noted in the literature for the first time. We describe these specimens and identify two distinct genera (Steneosaurus and Platysuchus) as present in the sample as well as three, or possibly four, distinct species. This represents a high diversity of teleosauroid taxa (both common and rare forms) from the Toarcian rarely seen elsewhere in the world.  相似文献   

16.
Abstract: Pleurotomaria species from lower Bajocian (Middle Jurassic) sediments of south‐western Luxembourg housed in the National Natural History Museum of Luxembourg are described. Seven species are recognized, one of which is new, Pleurotomaria faberi sp. nov. A more detailed definition of the diagnostic characters of the genus is proposed and the morphological continuity between Talantodiscus and Pleurotomaria is demonstrated, suggesting that the former cannot be considered as a distinct taxon. The palaeoecology, evolution and palaeobiogeographical history of Pleurotomaria are outlined. Pleurotomaria presumably first appeared in late Middle Triassic of New Zealand where it underwent a relative diversification up to the Hettangian (Early Jurassic). From early Hettangian, most of its evolutionary history took place in Europe and western Tethys. In the European epicontinental seas, Pleurotomaria experienced two important radiations. The first occurred in the Early Jurassic, with a peak in the late Pliensbachian, and was marked by an expansion of the distribution to the central part of western Tethys. After a collapse in species diversity, probably related to the early Toarcian anoxic event, a second radiation occurred. This culminated in the early Bajocian and was mainly confined in a region encompassing southern England, Paris Basin and southern Germany. Low‐spired species, formerly attributed to Talantodiscus, probably originated independently and iteratively during the history of Pleurotomaria. The facies and associated benthic faunas suggest that Pleurotomaria probably lived on shallow soft bottoms composed of mixed calcareous–siliciclastic sediments. The two main Early Jurassic and early Middle Jurassic radiations of the genus took place in these environments. Records of the genus in Jurassic carbonate platform deposits are very few and concern mainly post‐Bajocian species.  相似文献   

17.
18.
Detailed morphological study of the ring of the Jurassic saturnalid radiolarian species frequently cited in the literature as Hexasaturnalis suboblongus (Yao) has proven that it contains two well-defined species: H. suboblongus (Yao), practically ranging within the boundaries of the Bajocian, and Hexasaturnalis nakasekoi nov. sp., ranging within the Bathonian-Kimmeridgian interval. The two species seem to be important stratigraphically because the transition from the former to the latter took place at or around the Bajocian/Bathonian boundary. The phyletic lineage Hexasaturnalis hexagonus (Yao) → H. inuyamaensis (Yao) → H. suboblongus (Yao) → H. nakasekoi nov. sp. → H. minor (Baumgartner) → Dicerosaturnalis angustus (Baumgartner) → D. dicranacanthos (Squinabol) is proposed.  相似文献   

19.
Six new species of the genus Lasiosyne Tan et al., 2007, the type genus of the family Lasiosynidae Kirejtshuk et al., 2010, are described from Jurassic and Lower Cretaceous deposits of Mongolia and East Siberia: L. shartegiensis sp. nov., L. insculpta sp. nov., L. longitarsa sp. nov., L. cataphracta sp. nov., L. punctata sp. nov., and L. decora sp. nov. A modified diagnosis of the genus is proposed.  相似文献   

20.
L Rulleau  P Neige 《Geobios》2003,36(3):317-348
The genera usually considered into the Bouleiceratinae subfamily belong in fact to different lineages of the Hildoceratidae family. An approach using paleogeographical, stratigraphical and morphological arguments on one hand and a cladistic approach on the other hand have allowed to separate 3 clusters with different paleogeographical and stratigraphical localisations. These are:
the Bouleiceratinae s.s. (genera Bouleiceras, Nejdia and Kohaticeras) from lower Toarcian;
the Leukadiellinae (genera Leukadiella and Renziceras) from middle Toarcian;
and the Paroniceratinae (genera Frechiella, Paroniceras and Oxyparoniceras) from middle and upper Toarcian. These latters are mainly present and the Tethyan domain, but are also known in the NW of Europe and especially in France where new populations have been studied in the Causses, in the centre-ouest and in the Lyon area. New taxa have been erected here: Oxyparoniceras (Neoparoniceras) nov. sub. gen., O. (N.) brocardi nov. sp. and O. (N.) sciaui nov. sp.
  相似文献   

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