Late Jurassic Mammals from Tendaguru, Tanzania, East Africa

Records of Mesozoic mammals are extremely rare in Africa. The only previous record from the Upper Jurassic of Africa is a fragmentary mandible without teeth of Brancatherulum tendagurense. Here I report the discovery of two new mammals from the Upper Jurassic of Tendaguru, Tanzania. The fossils were recovered from the Middle Saurian Bed of the Tendaguru Series. A lower molar of a triconodontid mammal is described as Tendagurodon janenschi gen. et sp. nov., and a fragmentary dentary of a eupantothere as Tendagurutherium dietrichi gen. et sp. nov. The eupantothere in particular contributes to documenting the evolution of mammals during the Mesozoic. The posterior portion of the mandible of Tendagurutherium dietrichi gen. et sp. nov. shows that the angular (tympanic) bone was not yet completely separated from the dentary, a previously undocumented stage of eupantotherian middle ear evolution.     

A SECOND GONDWANAN DIPLODOCID DINOSAUR FROM THE UPPER JURASSIC TENDAGURU BEDS OF TANZANIA, EAST AFRICA

Abstract:  A new genus and species of diplodocid sauropod (Sauropoda, Diplodocoidea), Australodocus bohetii , is described. The type material from the Upper Jurassic (Tithonian) Tendaguru Beds of Tanzania, East Africa, consists of two successive mid-cervical vertebrae. These vertebrae do not show the extreme elongation of the cervical vertebrae that is diagnostic for Tornieria , and, apart from proportional differences, exhibit four autapomorphic characters not seen in other diplodocids: (1) pleurocoel weakly developed; (2) ridge posterolateral to the anterior condyle strongly posteroventrally orientated; (3) triangular pneumatic cavity ventral to the prezygapophysis, enclosed by the lateral ramus of the centroprezygapophyseal lamina and an anteriorly extended prezygodiapophyseal lamina; and (4) prominent prezygapophyseal process pointed, laterally keeled and surpassing the prezygapophysis anteriorly. Australodocus bohetii is the second diplodocid known from Tendaguru, and thereby the second diplodocid known from Gondwana. This impedes the customary reference of isolated East African diplodocid material to Tornieria , which can now only be assigned to Diplodocidae indet. The find supports previously proposed vicariance models of diplodocid palaeobiogeography.     

Elaphrosaurus,an ornithomimid dinosaur from the upper jurassic of north America and Africa

A humerus from the Morrison Formation (Upper Jurassic) of western North America is referred toElaphrosaurus which is represented by a skeleton from the Tendaguru Beds of Tanzania, East Africa. The referral ofCoelurus agilis Marsh (Morrison Formation, western U.S.A.) andTeinurosaurus sauvagei (Huene) (Kimmeridgian, France) toElaphrosaurus is incorrect. The recognition ofElaphrosaurus from North America provides additional evidence for a Morrison-Tendaguru land connection sometime during the Late Jurassic.Elaphrosaurus is referred to the family Ornithomimidae because the form of the humerus, slender and straight with a low deltopectoral crest, is diagnostic of this family.Deinocheirus from the Upper Cretaceous of Mongolia is a giant ornithomimid.     

湖北秭归盆地中侏罗世泄滩组孢粉组合

本文记录了鄂西秭归盆地东缘泄滩组上部21个属36个种的孢粉植物群,其中包括3个新种,讨论了主要属种组合特征和地层延限,根据中侏罗世孢粉植物群组合在国内外的对比,提出泄滩组上部Cyathidites minor-Classopollis-Callialasporites组合的时代属于中侏罗世,这个组合以桫椤科,掌鳞杉科植物的繁盛,和出现大量Cal-lialasporites母体植物为特点,暗示泄滩组上部形成于炎热而干旱的气候环境。     

AN ORIBATID MITE (ARACHNIDA: ACARI) FROM THE OXFORD CLAY (JURASSIC: UPPER CALLOVIAN) OF SOUTH CAVE STATION QUARRY, YORKSHIRE, UK

Abstract:  A single specimen of a new species of oribatid mite belonging to the genus Jureremus Krivolutsky, in Krivolutsky and Krassilov 1977 , previously described from the Upper Jurassic of the Russian Far East, is described as J. phippsi sp. nov. The mite is preserved by iron pyrite replacement, and was recovered by sieving from the Oxford Clay Formation (Jurassic: Upper Callovian) of South Cave, Yorkshire. It is the first record of a pre-Pleistocene mite, and the second species record of the family Cymbaeremaeidae, from the British Isles; also, it is only the third record of Acari from the Jurassic Period. The presence of a terrestrial mite in a sedimentary sequence of open marine origin is noteworthy, and suggestions for its mode of transport to the site of deposition are discussed.     

西北地区潮水盆地侏罗系青土井群轮藻化石

潮水盆地青土井群为一套含煤碎屑岩,在盆地东部潮参l井青土井群三段发育大量以Aclistochara占优势的轮藻化石群,其组合特征显示浓厚的晚侏罗世色彩。青土井群一、二段轮藻化石稀少,结合地层层序,推测其地质时代为早侏罗世。围岩沉积特征表明本井轮藻化石群为浅水生物群。     

吐鲁番盆地鄯善地区中、晚侏罗世介形类

报道吐鲁番盆地连木沁剖面七克以组及齐古组的介形类化石３属１０种,其中２新种１未定种;Ｔｈｅｒｉｏｓｙｎｏｅｃｕｍ？ｑｉｋｔｉｍｅｎｓｉｓ ｓｐ．ｎｏ。,Ｔｈ．ｈｕｏｙａｎｓｈａｎｅｎｉｓ ｓｐ．ｎｏｖ．,Ｄａｒｗｉｎｕｌａ ｓｐ．,根据化石组合面貌,自上而下可建立两个组合,即Ｄａｒｗｉｎｕｌａ－Ｍｅｔａｃｙｐｒｉｓ组合和Ｔｈｅｒｉｏｓｙｎｏｅｃｕｍ？－Ｄａｒｗｉｎｕｌａ组合,其时代分别为晚侏罗世和     

Storm deposits in the Jurassic of the Moroccan High Atlas

Certain carbonate deposits in the Upper Jurassic succession of the western High Atlas mountains of Morocco are interpreted as having resulted from periodic storms operating on very shallow marine or supratidal sediments. Such storm deposits or “tempestites” are thought to be much more common than is usually recognized, and in certain climatic situations they are likely to be the rule rather than the exception.     

Middle Jurassic fossils of the genus Sharasargus from Inner Mongolia, China (Diptera: Archisargidae)

To date, only two species of the genus Sharasargus are known. These Upper Jurassic species were found in Mongolia and Kazakhstan, respectively. We herein describe two new species from the Middle Jurassic, which were found in Inner Mongolia, China. They are the oldest known fossils of this genus. A key to Sharasargus species is given.     

Dinoturbation in Upper Jurassic siliciclastic levels at Cabo Mondego (Lusitanian Basin,Portugal): evidences in a fluvial-dominated deltaic succession

At Cabo Mondego (western central Portugal), the Upper Jurassic marine to coastal succession contains several stratigraphic levels preserving dinosaur footprints on the surface bedding plane, as well as convolute bedding and soft sediment injection structures interpreted as dinoturbation structures. At least nineteen new three-dimensional structures observed in cross-sections are interpreted as produced by dinosaur trampling. The identification of three-dimensional structures of dinosaur footprints provides an important complement to the information obtained from footprints preserved on single bedding surfaces, such as the substrate consistency, potential trackmaker identification, and the possibility to enhance the distinction of sauropods and tridactyl dinosaurs, and paleoenvironmental interpretations. In the lower part of the Arenitos da Boa Viagem Formation, eight levels of probable lowermost Kimmeridgian age (ca. 157–156 Ma), displaying the above-mentioned deformational structures, were analyzed in detail. They support interpretations concerning the relationship between the footprints and the substrate consistency at the time of their formation. Three distinct cohesiveness patterns, defined by the penetration of the feet from the paleosurface, are the result of different degrees of substrate cohesiveness. Identifying the trackmakers of levels belonging to the middle Oxfordian–lower Kimmeridgian has important implications for Late Jurassic ecosystem reconstructions, as the footprints observed in Cabo Mondego indicate a change in the morphotypes throughout the Upper Jurassic succession.     

Loriolella,a key taxon for understanding the early evolution of irregular echinoids

Loriolella Fucini is an enigmatic and poorly understood Early Jurassic sea-urchin that has been interpreted both as a regular and an irregular echinoid. The discovery of new and well-preserved material of the type species L. ludovicii (Meneghini) from the Upper Pliensbachian (Lower Jurassic) of Lombardy, Italy, has clarified the morphology of this genus for the first time. Loriolella resembles regular echinoids in having a large (almost certainly monocyclic) apical disc enclosing the periproct, and large primary interambulacral tubercles and spines. However, its peristome is extremely small with only vestigial buccal notches and auricles, and the ambulacra expand adorally forming cassiduloid-like phyllodes. Cladistic analysis suggests that Loriolella is the earliest known microstomatid irregular echinoid. Its unique mixture of primitive and derived characters is important for interpreting the initial steps by which irregular echinoids arose from diadematoid-like regular ancestors.     

The Upper Jurassic selachian Palaeocarcharias de Beaumont (1960)

The teeth of Palaeocarcharias stromeri De Beaumont (Kimmeridgian, Upper Jurassic; southern Germany) show linear gradient monognathic heterodonty from high-cusped parasymphyseal teeth to low-crowned posterolaterals. The bifid root has holaulacorhize vascularization and is surmounted by mesial and distal extensions of the triple-layered coronal enameloid. The crowns lack lateral cusplets, but possess short vertical striations at the base of the central cusp labially and lingually. A collar is developed at the base of the central cusp lingually, and a small node in a similar position labially. It is concluded that Palaeocarcharias must represent the oldest known lamniform. The body form of Palaeocarcharias is most closely comparable to that of the orectolobiform sharks, but the teeth are lamnoid. Palaeocarcharias is best interpreted as a benthonic stem group lamniform. The lamniforms are visualized as arising from orectolobiform ancestors, probably in the middle Jurassic.     

The complex nature of progenetic species — examples from Mesozoic ammonites

Several examples of progenetic species among Mesozoic ammonites are investigated. The ammonites are Middle Jurassic kosmoceratids, Upper Jurassic oppeliids, and Upper Cretaceous scaphites. As assessed through outgroup comparison, the progenetic species in each of these examples is characterized by small size at maturity and the presence of morphological features typical of those of the juveniles of more primitive species. However, in none of these examples is the progenetic species a duplicate form of the juvenile stage of more primitive species. There are at least three kinds of features of progenetic species that differ from those of the juveniles of more primitive species: (1) symplesiomorphous features associated with maturation, (2) unique features whose presence is not clearly related to progenetic processes, and (3) unique features that may represent epigenetic outgrowths of juvenile morphology. This novel combination of juvenile. adult. and unique features may endow progenetic species with the evolutionary potential to play a role in the origin of higher taxa. □ Progenesis, heterochrony, Ammon-oidea. Jurassic, Cretaceous.     

The Sporo-Pollen Assemblage of the red Beds of Nandian in Lancang of Yunnan

The Red Beds of Nandian consists mainly of red mud stone, marlite, quartzitic sand- stanc, Sabulous psephyte and fine psephyte. Predecessor divided them into three formations referring to Upper Triassic-Jurassic. The marlite in Upper Formation of the Red Beds are rich in fossil Sporo-pollen. The fossil spores and pollen contain 17 genera and 15 species, including 3 new species and 2 new combinations. The Sporo-pollen assemblage is characterized by the absolut predominance of the pollen of gymnospcrms (84.8%) compared with the spores of pteridophyta (15.2%), The pollen are specially characterized by the abundance of Classeopollis Pfiug (75.3%) with a certain amount of Psophosphaera (4.5%), Monosulites (2.4%) and a minority of Pinuspollenites (0.6%). The spores grains are characterized by the abundance of Cyathidites (4.1%), and also by presence of Calamospora (2.1%), Reticulatisporitcs (2.4%), Indeterminable form (1.2%), and rare Schizaeisporites (0.3%). Based on the sporo-pollen assemblage of Upper Jurrassic of the Eurasia continent is characterized by the absolute abundance of Classpollis Pflug (>50% of the total number), the Upper Formation oi the Red Beds of Nandian may be referred to Upper Jurassic age. The climate of the Nandian region in the Late Jurassic period is supposed to be as arid as that of Africa at the present time. Bundary of the eastern termination of southern part of the Eurasia continent in- ferred by Vakhrameev (1970) should be complemented.     

Jurassic neptunian dikes at Mt Mangart (Julian Alps,NW Slovenia)

Jurassic neptunian dikes are common within Upper Triassic to Lower Jurassic platform limestone of the Julian Alps. At Mt Mangart, the following geometries were observed: irregular dissolution cavities, thin penetrative fractures, larger fractures with sharp sidewalls, and laterally confined breccia bodies. Inside a complex neptunian dike system two main generations of infillings were differentiated. The first generation is heterogeneous and consists of bioclastic limestones, representing uniquely preserved sediments subdivided into five different microfacies. The second generation is more common and typically consists of coarse-grained breccias with host-rock clasts and marly limestone matrix containing echinoderms. Fracture formation and void filling of the first generation of neptunian dikes is dated as Pliensbachian and is interpreted to be caused by the Julian carbonate platform dissection due to widely recognized Lower Jurassic Tethyan rifting. The timing of formation for the second generation is only broadly constrained, ranging from the Pliensbachian to the Late Cretaceous.     

Ammonite eggs and ammonitellae from the Kimmeridge Clay Formation (Upper Jurassic) of Dorset, England

Eight clusters of small spherical and subspherical objects, some isolated and some associated with shells of perisphinctid ammonites, have been recovered from the Lower and Upper Kimmeridge Clay (Upper Jurassic) of the Dorset coast, England. They have been interpreted as ammonite egg sacs and represent the freshest and best-preserved examples known so far. Their structures and the ecological framework in which they occur are discussed. The parents are thought to be members of the two eudemic genera Aulacostephanus and Pectinatites that dominate the biostratigraphy of the ammonites in the range of the Kimmeridge Clay in which they occur. Isolated nuclei of ammonitellae have also been recovered.     

Reworked carboniferous spores: An example from the lower jurassic of northeast Scotland

An association of contemporaneous Jurassic mega- and miospores with reworked Carboniferous mega- and miospores is described from the Lower Lias rocks of northeast Scotland. The assemblage is compared with other accounts of reworked spores in Jurassic sediments. It is suggested that such reworking was particularly common in the Lower Jurassic of northern Europe and that four situations exist in the literature concerning probable cases of reworking: (1) the spores are recognised as reworked; (2) the identity of the spores as Carboniferous species is recognised and the “range” of these species is extended into the Jurassic; (3) the reworked spores are not recognised as such, and are incorrectly assigned to Jurassic genera and species; (4) the spores are recognised as Carboniferous, but their origin is attributed to contamination rather than reworking. In conclusion, the contrasting preservational features exhibited by the reworking and contemporaneous megaspores are discussed and interpreted as the result of differing depositional and postdepositional histories.     

A NEW SPECIES OF THE SPHENODONTIAN REPTILE CLEVOSAURUS FROM THE LOWER JURASSIC OF SOUTH WALES

Abstract:  Small reptiles from the Early Jurassic Pant 4 fissure fill in Glamorgan, South Wales (St. Bride's Island, Pant Quarry), were formerly provisionally attributed to three species of sphenodontian lepidosaurs. A re-analysis, aided by new material, has found this herpeto-fauna to consist almost exclusively of a single new species, Clevosaurus convallis sp. nov . , with only one specimen referable to Sphenodontia incertae sedis . Clevosaurus is known from the Upper Triassic and Lower Jurassic in various parts of the world, but C. convallis represents the first occurrence of the genus in the Jurassic of Britain. The material is fragmentary but includes numerous premaxillae, maxillae, dentaries and palatines, and the new species is distinguished by the unique combination of six large additional dentary teeth and a very short nasal process of the premaxilla, along with the diagnostic Clevosaurus features.