Ladinian radiolarian fauna from West Sichuan, China

A poorly preserved, but diversified radiolarian fauna was recovered from thin-bedded cherts occurring in the southeast of Daofu, Sichuan Province, southwestern China. Twenty-two radiolarian species belonging to 10 genera are identified and three new species (Paroertlispongus daofuensis n. sp., Falcispongus heinzi n. sp., Falcispongus pauliani n. sp.) are described. Falcispongus heinzi represents a transitional species between genera Oertlispongus inaequispinosus Dumitrica, Kozur and Mostler and Falcispongus Dumitrica. The fauna is divided into two assemblages, namely Muelleritortis cochleata and Oertlispongus inaequispinosus assemblages, which can be well correlated with the Ladinian radiolarian zones from Europe. The fauna indicates that basaltic rocks occurring in the Xianshuihe Belt were formed mainly during the Middle Triassic. Our results thus extend the previously known geological age of the Xianshuihe Belt to the Middle and Late Triassic interval.     

Latest Permian Spumellaria and Entactinaria (Radiolaria) from South China

A diverse and well-preserved latest Permian radiolarian fauna was obtained from bedded siliceous rocks and siliceous mudstones of the Dongpan Section, southwest Guangxi, China. All encountered specimens of the order Spumellaria and a few specimens of the order Entactinaria were selected for the taxonomic study of this paper. Thirty-three species, 15 of which are new species, were identified. They belong to 15 genera, three of which (Paracopicyntra, Copiconulus, and Yujingella) are new. The most interesting result of our study is that eight typical Middle Triassic spumellarian genera (Paroertlispongus Kozur and Mostler, Tetrapaurinella Kozur and Mostler, Paurinella Kozur and Mostler, Lithelius Haeckel, Archaeospongoprunum Pessagno, Tamonella Dumitrica, Kozur and Mostler, Bistarkum Yeh, and Tetraspongodiscus Kozur and Mostler) were discovered in the upper Changhsingian strata studied herein. Therefore, the most important and characteristic spumellarian families of the Middle Triassic were already present in the Late Permian of South China.     

Pleuromeia discovered from the Middle Triassic Linjia Formation of Benxi,Northeast China

A new species Pleuromeia shaolinii Zhang et Wang n. sp. was established under the family Pleuromeiaceae, based on eight specimens of stems and leaves, cones, rhizophores, and adventitious roots that were recently collected from the Middle Triassic Linjia Formation in Benxi, Northeast China. P. shaolinii n. sp. is similar to the type species P. sternbergii, in the morphology of the stem and rhizophore, but differs from it by the transversely rounded sporophylls organized in a heterosporous cone, and the two conspicuous triangular scars present on both sides of the vascular bundle scar. The Linjia flora, an only reliable Middle Triassic flora in Northeast China, was discovered 40 years ago. Although the Linjia Formation can be compared with the Middle Triassic Ermaying Formation from another area of the North China plate, its age was questionable due to the absence of the Early to Middle Triassic index fossil Pleuromeia. Based on the flora similarity, the zircon dating, lithologic characteristics, presence of a disconformity, and the occurrence of the Middle Triassic–Early Cretaceous insect fossil Sogdoblatta, the age of the Linjia Formation can be confirmed as Middle Triassic. The new species not only supplements our knowledge in biology and taxonomy of Pleuromeia, but also supports the Middle Triassic age assignment of the Linjia flora.     

On the miocene centracanthidae (Teleostei, Perciformes) from the eastern Paratethys

A new genus, Naslavcea, is erected for the Middle Miocene species Spicara fundata Bannikov, 1990 (Centracanthidae) from the Lower Sarmatian of northern Moldova. This genus is characterized by the relatively small number of rays in the dorsal and anal fins. At the same time, Pelates islamdagicus Prokofiev, 2001 from the Lower Miocene of the Apsheron Peninsula (Azerbaijan) is transferred from the family Terapontidae to Centracanthidae and referred to the genus Spicara.     

OnStaurikosaums pricei,an early saurischian dinosaur from the Triassic of Brazil,with notes on the Herrerasauridae and Poposauridae

The anatomy of the saurischian dinosaurStaurikosaums pricei Colbert from the Santa Maria Formation (Middle or Upper Triassic) of Rio do Sul, Brazil is redescribed.Staurikosaurus has 9 (or possibly 10) short cervicals, 15 dorsals and 2 sacral vertebrae, a modified brachyiliac pelvic girdle and an elongate hindlimb with the tibia longer than the femur. The new family Staurikosauridae is erected, the Herrerasauridae is redefined, and both families are considered to be Saurischia incertae sedis. The distal part of the “femur” ofPoposaurus gracilis Mehl (Upper Triassic, North America) is the ventral part of the pubes with a footed distal end but, because some members of the Poposauridae have an imperforate acetabulum, this family is transferred from the Saurischia (Theropoda, Carnosauria) to the Thecodontia (Pseudosuchia).     

Long Bone Histology of Sauropterygia from the Lower Muschelkalk of the Germanic Basin Provides Unexpected Implications for Phylogeny

Background

Sauropterygia is an abundant and successful group of Triassic marine reptiles. Phylogenetic relationships of Triassic Sauropterygia have always been unstable and recently questioned. Although specimens occur in high numbers, the main problems are rareness of diagnostic material from the Germanic Basin and uniformity of postcranial morphology of eosauropterygians. In the current paper, morphotypes of humeri along with their corresponding bone histologies for Lower to Middle Muschelkalk sauropterygians are described and interpreted for the first time in a phylogenetic context.

Methodology/Principal Findings

Nothosaurus shows a typical plesiomorphic lamellar-zonal bone type, but varying growth patterns and the occurrence of a new humerus morphotype point to a higher taxonomic diversity than was known. In contrast to the enormous morphological variability of eosauropterygian humeri not assigned to Nothosaurus, their long bone histology is relatively uniform and can be divided into two histotypes. Unexpectedly, both of these histotypes reveal abundant fibrolamellar bone throughout the cortex. This pushes the origin of fibrolamellar bone in Sauropterygia back from the Cretaceous to the early Middle Triassic (early Anisian). Histotype A is assigned to Cymatosaurus, a basal member of the Pistosauroidea, which includes the plesiosaurs as derived members. Histotype B is related to the pachypleurosaur Anarosaurus. Contrary to these new finds, the stratigraphically younger pachypleurosaur Neusticosaurus shows the plesiomorphic lamellar-zonal bone type and an incomplete endochondral ossification, like Nothosaurus.

Conclusions/Significance

Histological results hypothetically discussed in a phylogenetical context have a large impact on the current phylogenetic hypothesis of Sauropterygia, leaving the pachypleurosaurs polyphyletic. On the basis of histological data, Neusticosaurus would be related to Nothosaurus, whereas Anarosaurus would follow the pistosaur clade. Furthermore, the presence of fibrolamellar bone, which is accompanied with increased growth rates and presumably even with increased metabolic rates, already in Anarosaurus and Cymatosaurus can explain the success of the Pistosauroidea, the only sauropterygian group to survive into the Jurassic and give rise to the pelagic plesiosaur radiation.     

Late Triassic radiolarians of southern Cyprus

Radiolarians from the Upper Triassic of the allochthonous Mamonia Assemblage of southern Cyprus are considered. The Phasoula Formation, composed of basic volcanics, with lenses and interbeds of micritic limestones and cherts, contains (1) a Lower Norian assemblage with Capnodoce crystallina-Trialatus robustus, which also includes Capnodoce anapetes De Wever, Capnuchosphaera deweveri Kozur et Mostler, C. theloides De Wever, Deflandrecyrtium curvatum Kozur et Mostler, Icrioma cruciformis Tekin, Kahlerosphaera norica Kozur et Mock, Kinyrosphaera helicata Bragin, Mostlericyrtium sitepesiformis Tekin, Palaeosaturnalis latiannulatus Kozur et Mostler, Spongostylus tortilis Kozur et Mostler, Xiphotheca rugosa Bragin, and Zhamojdasphaera proceruspinosa Lahm; (2) a Middle Norian assemblage with Capnodoce sarisa accompanied by Loffa mulleri Pessagno, Nabolella trispinosa Bragin, and Praexehasaturnalis tenuispinosus (Donofrio et Mostler); and (3) an Upper Norian assemblage with Livarella densiporata-Lysemelas olbia accompanied by Pentactinocarpus sevaticus Kozur et Mostler, Praemesosaturnalis multidentatus (Kozur et Mostler), and others. This assemblage also occurs in clastic turbidites of the Vlambouros Formation. In the sections of southern Cyprus, radiolarian zones are recognized that correspond to the zones previously established in the Far East of Russia, which include Capnodoce crystallina (Lower and Middle Norian) and Lysemelas olbia (lower part of the Upper Norian). Radiolarians belonging to three orders, 24 families, 59 genera, and 101 species are described; of them 2 genera, 9 species, and 1 subspecies were previously described by the author; 14 new species and 1 new subspecies are established. The diagnoses of many genera and species are emended, the stratigraphic and geographical ranges of the majority of taxa are substantially expanded.     

Triassic nannoplankton limestones of deep basin origin in the central mediterranean region

Samples of Triassic pelagic limestones collected in several regions of the Central Mediterranean area were examined with the electron microscope. They show calcareous nannoplankton existing already from Middle Triassic time. The Middle Triassic nannofossils are contained in nodular limestones such as the “Ammonitico Rosso” of Epidaurus (Greece); the Upper Triassic ones are contained in nodular limestones like the Ammonitico Rosso of Hallstatt (Austria), as well as in Halobia cherty limestones of the Pindos basin in Italy, Yugoslavia and Greece. In the Halobia limestones it is possible, in spite of the recrystallization effects, to recognize such an abundance of organic forms — even if in fragments — that we can suppose the original sediment to be a kind of nannoplankton ooze.Because of the very low accumulation rate (few metres/m.y.) of the Middle Triassic Ammonitico Rosso limestones, the coccoliths cannot be considered a significant factor of carbonate pelagic sedimentation at this time; the very high accumulation rate (up to 25 metres/m.y.) of the Upper Triassic cherty limestones in the Pindos basin, on the contrary, allows the nannoplankton to be considered a very important agent of calcareous pelagic sedimentation. The authors hypothesize that the Dogger-Malm, mainly represented by radiolarites, was only a temporary interlude in the Mesozoic pelagic carbonate sedimentation.     

A new Neocalamites (Sphenophyta) with prickles and attached cones from the Upper Triassic of China

Remains of the extinct sphenophyte (horsetail) Neocalamites are most widespread in the Middle–Upper Triassic and are typically represented by stem and leaf fragments. Here we report on spectacular new finds of Neocalamites from the Late Triassic Yangcaogou Formation in Liaoning Province, China that include bedding surfaces dominated by nearly complete aerial stems with attached leaf whorls and rare bractless cones. They reveal a monopodial growth habit for the stems, which are covered with downward projecting prickles that probably provided protection against herbivores. These features provide the basis for a new proposed species, Neocalamites horridus. The nodes bear whorls of very long leaves mainly free to their bases, and one specimen bears an attached cone on a long peduncle. Identical dispersed cones have also been recovered. The leaves of adjacent monopodial stems most likely interlocked to support growth in large stands akin to the role now played by branches in large modern Equisetum species. The new Chinese Neocalamites is among the most confidently reconstructed species, and indicates a greater diversity of sphenophyte morphology during the Mesozoic than previously realized.     

Palynological characterisation of the Lower Carnian of the KEA5 borehole (Koudiat El Halfa Dome; Central Atlas, Tunisia)

In Central Tunisia, the Triassic outcrops of the Koudiat El Halfa and Rheouis Domes are mainly composed of an evaporite-dominated succession. The scarce biostratigraphic data available to date assign a Ladinian-Carnian age for the outcropping strata. The present palynological study data demonstrate an Early Carnian (Julian) age for the Triassic sediments penetrated by the KEA5 borehole in the Koudiat El Halfa Dome, which were previously considered to represent Middle Triassic. The palynological record mainly consists of Enzonalasporites vigens, Patinasporites densus, Vallasporites ignacii, Brodispora striata, Samaropollenites speciosus, Ovalipollis pseudoalatus in association with Circumpolles species such as Praecirculina granifer, Camerosporites secatus and Duplicisporites granulatus. In addition, Lagenella martini and Aulisporites astigmosus occur in the upper part of the drilled succession and their first appearance could indicate a Julian-Early Tuvalian age. These new data allow a palynostratigraphic correlation with the Rheouis Formation cropping out along the structural “North-South Axis” of Central Tunisia, particularly in the Jebel Rheouis Dome. The drilled succession can be correlated with the Black Dolostones (Tr3) and the Middle Gypsum (Tr4) members of the Rheouis Formation.     

First 'Rauisuchian' archosaur (Pseudosuchia,Loricata) for the Middle Triassic Santacruzodon Assemblage Zone (Santa Maria Supersequence), Rio Grande do Sul State,Brazil

The ‘Rauisuchia’ are a group of Triassic pseudosuchian archosaurs that displayed a near worldwide distribution. In Brazil, their fossils are found only in the Santa Maria Formation (Paraná Basin) of the Rio Grande do Sul State, specifically in the Middle Triassic Dinodontosaurus assemblage zone (AZ) and the Late Triassic Hyperodapedon AZ (Rauisuchus tiradentes). Between these two cenozones is the Santacruzodon AZ (Middle Triassic), whose record was, until now, restricted to non-mammalian cynodonts and the proterochampsian Chanaresuchus bonapartei. Here we present the first occurrence of a rauisuchian archosaur for this cenozone, from the Schoenstatt outcrop, located near the city of Santa Cruz do Sul and propose a new species, based on biostratigraphical evidence and a comparative osteological analysis.     

New finds ofOmphalosaurus and a review of Triassic ichthyosaur paleobiogeography

Triassic ichthyosaurs are very widespread and diverse but most taxa are poorly known. New discoveries, such as described in this paper, underscore the first statement but only slowy invalidate the second. The first associated skeleton of the unusual durophagous ichthyosaurOmphalosaurus (O. wolfi) is reported from the Middle Triassic (earliest Ladinian) of the northern Alps. The vertebrae are of the ichthyosaurian type, firmly establishing the ichthyosaurian affinities of the genus. A round bone from the Muschelkalk of Franconia, Germany, is identified and described as a left humerus ofOmphalosaurus sp. These finds greatly extend the paleogeographic and temporal range ofOmphalosaurus which previously was only known from the western cratonic margin of North America and from Spitsbergen. The new records ofOmphalosaurus allow a revised differential diagnosis of the genus and a revision of its species. Valid species ofOmphalosaurus areO. nettarhynchus, O. nevadanus, andO. wolfi. In conjunction with such new insights into Triassic ichthyosaur distribution, it is necessary to address the validity of the poorly known genera such as the Middle TriassicPessosaurus. This taxon must be considered invalid because it lacks diagnostic characters. In assessing progress in research on Triassic ichthyosaurs and their paleobiogeography, it becomes apparent that supra-specific diversity appears largely known, at least for the pre-Norian record of North America, Europe, and East Asia.     

Parafurnishius,an Induan (Lower Triassic) conodont new genus from northeastern Sichuan Province,southwest China and its evolutionary implications

A fundamental aspect of taxonomy at the generic level, critical to understand Early Triassic conodont evolution, is the composition of the multielement apparatus. In this paper, we document a platform-bearing new conodont genus, Parafurnishius n. gen., as well as its multielement apparatus from the Griesbachian Feixianguan Formation (Lower Triassic) in Xuanhan County, northeastern Sichuan Province, southwest China. The new conodont genus is characterized by numerous robust and irregularly distributed conical denticles with variable platform morphology that has a possible affinity with the P₁ elements of Furnishius. These genera have apparatuses similar to those of Ellisonia and are classified with the family Ellisoniidae. The strong intraspecific variation of P₁ elements and the growth series within the entire sample population suggest that Parafurnishius may have evolved from the Griesbachian Isarcicella by developing random denticle positioning away from the platform centre, and then possibly evolved into younger Triassic Furnishius by developing a stable blade configuration. This preferred interpretation implies an ellisonid apparatus for Isarcicella. Alternatively, Parafurnishius may have evolved from Ellisonia and developed a homeomorphic P₁ element with Isarcicella. This new taxon has strong intraspecific variation of denticle growth orientation during the Early Triassic.     

The Ramonalinids: a new family of mound‐building bivalves of the Early Middle Triassic

Abstract: Ramonalina n. gen. is a large thick‐shelled bivalve abundant in mounds preserved in the Gevanim Formation (late Anisian, Middle Triassic) of southern Israel. This bivalve was an edgewise‐recliner with a flattened anteroventral (functionally basal) surface and partially fused valves. It is the basis of a new family, the Ramonalinidae, which is descended from the myalinids through adaptation to edgewise positioning. Ligamental attachment was inadequate to hold valves together on large adults, resulting in valve displacement followed by shell secretion in the apical area that fused valves together and caused irregular growth on abapical areas. The ramonalinids formed large, nearly monospecific mounds on firm mud substrates in shallow marine waters. These are the largest Middle Triassic bivalve mounds known.     

An early isocrinid sea lily from the middle to late Anisian boundary (Middle Triassic) of south‐west China – evidence for a far‐east Tethyan origin of the family Isocrinidae

Abstract: The isocrinid sea lily Tyrolecrinus wugangi sp. nov. from uppermost middle to lowermost upper Anisian (lower Middle Triassic) strata of Leidapo near Qingyan, Guizhou Province, south‐west China, provides new data on the early phylogeny of the order Isocrinida. The new species is the earliest unequivocal representative of the family Isocrinidae. It predates all other known species of the genus Tyrolecrinus that come from upper Ladinian to Rhaetian strata and also all other known taxa of the Isocrinidae. Nevertheless, its stem is of fully developed isocrinid type and is characteristic of the genus, with consistently synostosial, rarely cryptosymplectial, distal nodal articular facets. These findings indicate that the Isocrinidae evolved prior to the late middle Anisian in the far‐eastern part of the Palaeotethys ocean, perhaps in the region forming today’s south‐west China, and spread to various other regions later in the Middle and Late Triassic. The genus Tyrolecrinus is revised and the new genus Bakonycrinus gen. nov. is erected.     

Aboral nervous system in two Ordovician crinoids: Reconstruction and comparison of Baltic <Emphasis Type="Italic">Pentamerocrinus</Emphasis> Jaekel and <Emphasis Type="Italic">Grammocrinus</Emphasis> Eichwald

Two unusual Middle Ordovician crinoid genera from the St. Petersburg Region, Pentamerocrinus Jaekel, 1918 and Grammocrinus Eichwald, 1860, are redescribed. A new species, Pentamerocrinus kosovi sp. nov., is described based on new material and the cup structure in the type species Grammocrinus lineatus, which has previously been known only from stem fragments, is reconstructed. The system of ridges and canals on the internal surface of the cup plates in both genera is described, allowing the reconstruction of the aboral nervous system. It is in general similar to extant crinoids, but the two Ordovician genera differ considerably in structural details. In Pentamerocrinus, ten nerve cords diverge interradially from the ganglionated nerve ring at the cup base and soon are fused in pairs inside the rays. In Grammocrinus, a similar nerve ring also gives rise to ten cords, but they are inside the rays and become fused in the interrays. This distinction in morphology of the nervous systems is correlated with the interradial arrangement of the axial canal angles of the stem in the first case and radial in the second. Therefore, despite general similarity in the structure and arrangement of calyceal plates, the genus Grammocrinus is assigned to the disparid crinoid family Iocrinidae, while the monotypic family Pentamerocrinidae Jaekel, 1918 is regarded as a fam. inc. sed. of inadunate crinoids.     

Mikadocephalus gracilirostris n. gen., n. sp., a new ichthyosaur from the Grenzbitumenzone (Anisian-Ladinian) of Monte San Giorgio (Switzerland)

An almost complete skull of a new ichthyosaur from the Middle Triassic Grenzbitumenzone Beds of Monte San Giorgio (Kanton Tessin, Switzerland) represents one of the most complete and best preserved finds of a large Triassic ichthyosaur cranium. Its affinites with other Triassic ichthyosaur taxa are discussed and it is demonstrated to represent a new genus and species,Mikadocephalus gracilirostris, which does not fit into any of the currently recognized families of Triassic ichthyosaurs. Remarkable similarities in cranial structure exit to postTriassic ichthyosaurs, with which a number of important apomorphies are shared.     

A New Species of Garjainia Ochev, 1958 (Diapsida: Archosauriformes: Erythrosuchidae) from the Early Triassic of South Africa

A new species of the erythrosuchid archosauriform reptile Garjainia Ochev, 1958 is described on the basis of disarticulated but abundant and well-preserved cranial and postcranial material from the late Early Triassic (late Olenekian) Subzone A of the Cynognathus Assemblage Zone of the Burgersdorp Formation (Beaufort Group) of the Karoo Basin of South Africa. The new species, G. madiba, differs from its unique congener, G. prima from the late Olenekian of European Russia, most notably in having large bony bosses on the lateral surfaces of the jugals and postorbitals. The new species also has more teeth and a proportionately longer postacetabular process of the ilium than G. prima. Analysis of G. madiba bone histology reveals thick compact cortices comprised of highly vascularized, rapidly forming fibro-lamellar bone tissue, similar to Erythrosuchus africanus from Subzone B of the Cynognathus Assemblage Zone. The most notable differences between the two taxa are the predominance of a radiating vascular network and presence of annuli in the limb bones of G. madiba. These features indicate rapid growth rates, consistent with data for many other Triassic archosauriforms, but also a high degree of developmental plasticity as growth remained flexible. The diagnoses of Garjainia and of Erythrosuchidae are addressed and revised. Garjainia madiba is the geologically oldest erythrosuchid known from the Southern Hemisphere, and demonstrates that erythrosuchids achieved a cosmopolitan biogeographical distribution by the end of the Early Triassic, within five million years of the end-Permian mass extinction event. It provides new insights into the diversity of the Subzone A vertebrate assemblage, which partially fills a major gap between classic ‘faunal’ assemblages from the older Lystrosaurus Assemblage Zone (earliest Triassic) and the younger Subzone B of the Cynognathus Assemblage Zone (early Middle Triassic).     

New fossil insects from the Anisian (Lower to Middle Muschelkalk) from the Central European Basin (Germany and The Netherlands)

The Palaeozoic–Mesozoic transition is characterized not only by the most massive Phanerozoic mass extinction at the end of the Permian period, but also its extensive aftermath and a prolonged period of major biotal recovery during the succeeding Middle to Late Triassic. Particularly, Anisian insect species from units of the Lower to Middle Muschelkalk from the Central European Basin are rare. The specimens described here originated from the Anisian Wellenkalk facies (Lower Muschelkalk), Vossenveld Formation of the Winterswijk quarry, The Netherlands, and from the orbicularis Member (lowermost Middle Muschelkalk, Anisian) of Esperstedt near Querfurt (Saxony-Anhalt). Thus, the described insect remains from Winterwijk and Esperstedt expand our knowledge about Middle Triassic terrestrial arthropod communities and their palaeodiversity. A new species of Chauliodites (C. esperstedti sp. nov) is introduced.