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Peggy Vincent Nathalie Bardet Xabier Pereda Suberbiola Badi Bouya Mbarek Amaghzaz Saïd Meslouh 《Gondwana Research》2011,19(4):1062-1073
Though the Maastrichtian Phosphates of Morocco have yielded very rich marine vertebrate assemblages, plesiosaurs remain very scarce in these strata. The only hitherto recognized taxon was Plesiosaurus mauritanicus Arambourg, 1952, regarded here as a nomem dubium. Here we describe a new genus and species of elasmosaurid plesiosaur, Zarafasaura oceanis, which represents the first valid elasmosaurid plesiosaur described from the latest Cretaceous of Africa, and the second one from this continent. A phylogenetic analysis of plesiosauroids indicates that Zarafasaura oceanis has close affinities with elasmosaurids from the Late Cretaceous of North America and Japan. Among its distinctive suite of characters, the general shape and organisation of its squamosal and palate are unique among elasmosaurids. This new taxon completes our understanding of Late Cretaceous plesiosaur palaeobiodiversity and palaeobiogeography, and shows that Maastrichtian plesiosaurs were characterized by a quite high degree of endemism. They were also highly diversified and distributed worldwide, which supports the hypothesis of a catastrophic extinction of plesiosaurs at the K/T boundary. 相似文献
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Yabeinosaurus was the first lizard genus described from the Early Cretaceous Jehol Biota of China. The holotype of the type species, Y. tenuis, is an immature skeleton but it has been lost for decades. A second species, Y. youngi, was erected based on another immature skeleton and is distinguished by its longer, more gracile limbs. In 2001, a juvenile skeleton from the Jingangshan locality of Liaoning was designated as the neotype for Y. tenuis. Subsequently, several further specimens from other localities, juvenile and adult, have been attributed to this species. Here we describe a second lizard specimen from the neotype locality. In anterior tooth shape, finger-like mandibular angular process, cranial sculpture, maxilla shape, and short, robust humerus, the new specimen resembles adult and subadult material currently attributed to Y. tenuis, but it differs in having bicuspid posterior teeth and a straight rather than a hooked angular process of the mandible. We propose a new species (Y. bicuspidens sp. nov.) for this specimen which represents the first occurrence of bicuspid teeth in an Early Cretaceous lizard from China. However, the recognition of a second species at the neotype locality raises a taxonomic problem. Due to the immaturity of the designated holotype and neotype of Y. tenuis, they cannot be coded for the jaw and dental characters that distinguish the two robust-limbed species. This renders Yabeinosaurus tenuis a nomen dubium. Here we propose that Yabeinosaurus tenuis should be treated as a historic taxon, permitting retention of the generic name under ICZN rules, and erect a second new species (Y. robustus sp. nov.) for the principal robust-limbed morphotype in the Jehol Biota with monocuspid posterior teeth and a hooked angular process. 相似文献
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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
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Recent work in the Tropic Shale by the Museum of Northern Arizona reveals a high biodiversity for plesiosaurs along the western margin of the Cretaceous Western Interior Seaway during the Cenomanian and the Turonian. This paper describes a new species of polycotylid plesiosaur from the Tropic Shale, Dolichorhynchops tropicensis, which adds to the known biodiversity from this time period. The identification is based on two specimens, a well-preserved, nearly complete skeleton including the skull and an additional specimen with only fragmentary skeletal elements. The material shares several synapomorphic characters with Dolichorhynchops, including the shape of the temporal fenestrae, the shape of the sagittal crest, the trend of the ectopterygoids, the morphology of the teeth, and the number of teeth within the mandibular symphysis. D. tropicensis differs from other species of Dolichorhynchops in a greater size range of the teeth, moderately constricted dorsal vertebrae, angled anterior processes on the coracoids, and the presence of well-defined facets on the propodials. The specimens are of Early Turonian age (based primarily on ammonite biostratigraphy and bentonite marker beds), and their discovery extends the known stratigraphic range for Dolichorhynchops back by approximately seven million years. This suggests that Dolichorhynchops tropicensis and Trinacromerum bentonianum, a closely related polycotylid, co-existed in the Western Interior Seaway. 相似文献
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A new larger benthic foraminifer is described as Braciana jelaskai n. gen., n. sp. from lower Campanian shallow-water foraminiferal wackestones to packstones of the island of Brač, Croatia. The Late Cretaceous Braciana is roughly homeomorphic to the Liassic taxa Lituolipora (type-species L. polymorpha Gušić & Velić) and Paleomayncina Septfontaine (type-species Mayncina termieri Hottinger). The generic differences to these taxa and other allied forms are discussed. Braciana jelaskai was confused with Pseudocyclammina sphaeroidea Gendrot in the literature with occurrences in the Santonian(?) of Slovenia and Greece. 相似文献
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Although the Cretaceous is characterized by a rich fish diversity, Cretaceous continental fishes from Gondwana are poorly known and comparatively scarce. Among these fishes, the family Pleuropholidae is only known by a few species relatively poorly preserved, from the Middle Jurassic to Lower Cretaceous of Europe, Africa, North America, and South America. In this paper, two new species of the pleuropholid new genus Zurupleuropholis are described, Z. quijadensis gen. et sp. nov. and Z. decollavi gen. et sp. nov. The new fishes were recovered in the Lower Cretaceous lacustrine Lagarcito Formation of central-west Argentina. This taxon constitutes a relevant finding considering that the representation of the family Pleuropholidae is rare worldwide. Zurupleuropholis gen. nov. appears to be the youngest known member of Pleuropholidae, and it represents the second record of the family in South America and the first record in the Cretaceous of the continent. 相似文献
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A charophyte flora from the Upper Berriasian is described from the Lakota (Black Hills, South Dakota) and Cedar Mountain formations (San Rafael Swell, Utah) of the Western Interior Basin, United States of America. Whereas the latter is dominated by monotonous assemblages of the clavatoracean Nodosoclavator bradleyi (Harris, 1939), found in temporary lakes within palustrine facies, the flora of the Lakota Formation consists of more varied assemblages of the clavatoraceans N. bradleyi (Harris, 1939), Clavator grovesii grovesii Harris 1939, C. bilateralis Peck 1957 and early characeans (Mesochara sp. or Tolypella sp.). This flora was found in deposits related to permanent lakes in fluvial floodplains, i.e. lacustrine marls and limestones that do not show any evidence of subaerial exposure. To date, little is known about C. bilateralis, we provide a new definition on the basis of its particular structure, which shows lateral bract-cell units with a pinnate arrangement. This species appears to be endemic to North America and stratigraphically limited to the earliest Cretaceous. C. grovesii grovesii is part of a long-lasting charophyte lineage, which until now was considered to have originated in the Central Tethyan Archipelago (Europe) during the Early Berriasian, about 145 Ma, and limited to Eurasia until most of the Early Cretaceous. The new data presented here suggest that during the Berriasian this species was very broadly distributed, comprising North America, Europe and China. 相似文献
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Catfish bones from Tortonian (Miocene) freshwater beds of central Argentina are here identified as pertaining to a new species of the tropical pimelodid genus Phractocephalus. The new species differs from the other recent and fossil species of the genus in skull, pectoral girdle and spine characters. The material was found in different localities near the city of Paraná, Entre Ríos Province. The bearing horizon is the so-called “Conglomerado osífero” which constitutes the lowermost beds of the fluvial Ituzaingó Formation. The aquatic vertebrate fauna occurring in the bearing bed shows a similar generic composition to several northern South American Miocene units where Phractocephalus remains were found. This report extends the range of Phractocephalus more than 2000 km to the South. The record is in agreement with higher global temperatures and putative ample hydrographic connections of the river basins in the Paraná area with the Amazon basin until at least the early late Miocene. 相似文献
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The Early Cretaceous lizard Yabeinosaurus was one of the first taxa described from the now famous Jehol Biota of northeast China. Misinterpreted for more than 60 years and misclassified as a gekkotan based on juvenile specimens, it is now recognised to be a large, well-ossified lizard with an extended period of skeletal maturation. Here we describe two additional complete specimens of Yabeinosaurus that provide new information on skeletal morphology, most notably of the skull, pectoral girdle, and tail. Both specimens also preserve gut contents, showing that large individuals took vertebrate prey, including fish. A more complete understanding of Yabeinosaurus permits a review of the type specimen of Yabeinosaurus youngi. Skull traits used to distinguish Y. youngi from Yabeinosaurus tenuis are invalid but, as noted by Hoffstetter, the two species differ markedly in limb proportions. Attribution of Young’s specimen to Yabeinosaurus is equivocal, but could potentially extend the temporal range of the lineage into the Jurassic. A new phylogenetic analysis based on a morphological data set places Yabeinosaurus on the stem of Scleroglossa, as the sister taxon of the contemporaneous Japanese lizard Sakurasaurus. 相似文献
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A gastrolith set, comprising 197 elements, associated with an indeterminate elasmosaurid plesiosaur collected from the Campanian–Maastrichtian La Colonia Formation, Chubut, Argentina, is described. Most of the gastroliths are discoidal (41.9%) or spheroidal (34.8%), with a mean Maximum Projection Sphericity Index value of 0.69 and a mean OP Index value of −0.74. The values of these indices are compared with those recorded for gastroliths associated with other Upper Cretaceous elasmosaurids to see if patterns with palaeobiological relevance are evident. The mean values of the Maximum Projection Sphericity Index and the Oblate-Prolate Index allow us to infer a fluvial or estuarine origin for all the elasmosaurid gastroliths for which these indices have been calculated. This inference is palaeobiologically informative because it indicates that at least some Upper Cretaceous elasmosaurs entered into estuarine (or fluvial) environments. It also helps explain the interesting vertebrate assemblage of the Allen and La Colonia formations where a rich continental fauna is recorded but elasmosaurids and polycotylids are the only well represented vertebrates with marine affinities. 相似文献
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A new tree fern stem,Tempskya zhangii sp. nov. (Tempskyaceae) from the Cretaceous of Northeast China
A new Cretaceous tree fern species from the family Tempskyaceae, Tempskya zhangii sp. nov., from Keshan County, Heilongjiang Province, Northeast China, is described based on silicified fragments. The species is characterized by dichotomizing stems embedded in a matrix of adventitious roots, together forming a solid and compact false trunk. The dorsiventral stems are composed of solenosteles, and their internodes are short with 2–3 (rarely 4) leaf traces. A three-layered cortex includes a sclerenchymatous outer zone, parenchymatous middle zone, and an inner zone composed of sclerenchyma band and parenchyma cells. The pith consists of a parenchymatous outer zone and sclerenchymatous inner zone. The petiole has a single C- or U-shaped vascular strand. The adventitious root has diarch xylem surrounded by an inner sclerenchymatous and an outer parenchymatous cortex. In possessing these characters, T. zhangii is more similar to T. wyomingensis from the Cretaceous of North America than to other species of Tempskya. However, the Chinese species distinctly differs from T. wyomingensis in having a sclerenchymatous outer cortex, parenchymatous middle cortex, and sparse parenchyma in the xylem. It is the first record of Tempskya from China and the fourth from Asia. This species, together with Cyatheaceae, Osmundaceae, Cycadeoidaceae, and conifers found in the same region constituted the plant community at the time. 相似文献
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A new genus and species of small (3.5 mm excluding ovipositor) parisitoid wasp is described from the Lower Cretaceous (Aptian) Crato Formation Lagerstätte of Brazil. Parviformosus wohlrabeae gen. et sp. nov. is known from a single female imago and is assigned to Pteromalidae. It is diagnosed by the robustness of the scutellum, the structure, size and positioning of the mesopleuron, the complexity of the propodeum–petiole junction and a posteriorly curved dorsal ‘lip’ on metasomal segment 4. At only 3.5 mm in length, P. wohlrabeae is the smallest fossil wasp from the Cretaceous of South America and the first Mesozoic representative of Pteromalidae. 相似文献
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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
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《China Geology》2020,3(1):1-7
A new dsungaripterid pterosaur, Ordosipterus planignathus gen. et sp. nov., is established on the incomplete articulated lower jaws from the Lower Cretaceous Luohandong Formation in Otog Qi, Ordos Region, Inner Mongolia, China. It differs from other dsungaripterids mainly by having broad and low dentary at and just behind the mandibular symphysis, flat dentary dorsal plane forming the distinct lateral ridge with the curved dentary lateral side, and lower alveoli arranged along the dentary dorsolateral margin with wide spacing that increases from rostral to caudal. It represents the first diagnostic pterosaur from the Ordos Region in Inner Mongolia, and further enlarges the geographical distribution of the family Dsungaripteridae from northwestern China (together with western Mongolia) to central North China. 相似文献
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Cenomanian rocks of Egypt are rich in moderately to well-preserved echinoids. From the large Cretaceous echinoid collection at the Cairo Geological Museum, a total of 27 regular species, in 12 genera, eight families, six orders and two subclasses, are revised and systematically described from these strata as exposed at several localities in Egypt. One new family (Pedinopsidae), one new subfamily (Lorioliinae), one new genus (Alternocidaris) and two new species of Goniopygus, G. subaequalis (Gebel Ekma) and G. macrotuberculatus (Gebel El Minsherah), are erected. Additionally, two species of Diplopodia, D. micropyga Fourtau, 1921 and D. halperti Fourtau, 1921, are transferred to the genus Pedinopsis. 相似文献
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A new genus, Cretasyne gen. nov., in the family Lasiosynidae, with two species C. lata sp. nov. and C. longa sp. nov., is described from the Lower Cretaceous Yixian Formation of Inner Mongolia, China. These fossils are the first record of the family from the Yixian Formation and provide significant information on lasiosynid morphology and diversity. The fossil record of Lasiosynidae is also reviewed. 相似文献
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The Coccondontoidea is a distinctive superfamily of pycnodont fishes characterized by a series of derived characters, including thick and well-ossified cranial bones supporting horns and spines and a hypertrophied pectoral girdle sutured to the skull forming a sort of cephalo-torax. A new distinctive coccodontoid species, Gladiopycnodus byrnei n. sp., is described from the Cenomanian locality of Hjoûla, Lebanon. This new species exhibits a unique combination of features that clearly support its inclusion within the coccodontoid family Gladiopycnodontidae, including an extremely elongate snout forming a sword-shaped rostrum, thick dermal bones ornamented with rounded tubercles, large supracleithrum and cleithrum extensively sutured to the skull, and irregularly imbricated scales covering the entire body. The new taxon differs from type species G. karami by having different meristic counts and body proportions, dermal bones strongly ornamentated, skull roof with partially fused bones, scales ornamented with small tubercles, and rounded scales covering the caudal peduncle absent. The presence of pectoral fins in our exquisitely well-preserved specimen allowed us to redefine the morphology of the genus Gladiopycnodus, also modifying the diagnosis of the family. In order to interpret the patterns of morphospace occupation and quantify the morphological diversification of pycnodonts through time, the geometric morphometric approach was used. The morphospace analysis revealed that a significant increase in morphological disparity of pycnodonts during the Late Cretaceous was related, at least in part, to the appearance of the representatives of the superfamily Coccodontoidea. The rapid evolutionary radiation of these well-armored pycnodonts was interpreted as an adaptive solution in response to the large predatory-prey escalation in the context of the Mesozoic Marine Revolution. 相似文献