A new elasmosaurid specimen from the upper Maastrichtian of Antarctica: new evidence of a monophyletic group of Weddellian elasmosaurids

O’Gorman, J.P. & Coria, R.A. September 2016. A new elasmosaurid specimen from the upper Maastrichtian of Antarctica: new evidence of a monophyletic group of Weddellian elasmosaurids. Alcheringa 41, xxx–xxx. ISSN 0311-5518

A new fossil elasmosaurid specimen, MLP 15-I-7-48, from the upper Maastrichtian Sandwich Bluff Member of the López de Bertodano Formation, Vega Island, Archipelago James Ross, Antarctica, is described. The fossil is a well-preserved anterior limb, which shares with Vegasaurus molyi from the upper Maastrichtian of Antarctica, a concave to flat anterior margin of the humeral shaft, and with Vegasaurus molyi and Aphrosaurus furlongi from the upper Maastrichtian of California, a well-defined depression on the anterior margin of the ventral surface of the humeral shaft. A phylogenetic analysis recovered MLP 15-I-7–48 as sister group of the lower Maastrichtian Vegasaurus molyi within a new clade nominated as Weddellonectia: Kawanectes lafquenianum ((Vegasaurus molyi; MLP 15-I-7–48) (Morenosaurus stocki (Aristonectinae))). This indicates that the previously proposed faunal turnover between the early and late Maastrichtian Weddellian marine reptile fauna, did not severely affect the non-aristonectine elasmosaurids. Additionally, other taxa previously considered evidence of a faunal turnover are re-evaluated.

José P. O’Gorman. [joseogorman@fcnym.unlp.edu.ar]. División Paleontología Vertebrados, Museo de La Plata, Universidad Nacional de La Plata, Paseo del Bosque s/n., B1900FWA, La Plata, Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina. Rodolfo A. Coria. [rcoria@unrn.edu.ar]. Instituto de Investigación en Paleobiología y Geología, Universidad Nacional de Río Negro—Subsecretaría de Cultura de Neuquén—Museo Carmen Funes, Av. CVórdoba 55 (8318), Plaza Huincul, Neuquén, Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina.     

Late quaternary Palorchestes azael (Mammalia,Diprotodontidae) from northwestern Tasmania

A fossil mandible and incisor of the diprotodontid marsupial Palorchestes azeal Owen is reported from a new locality at Pulbeena, near Smithon, in northwestern Tasmania. The fossils occurred with a piece of wood which has a ¹⁴C age of 54,200_-4,500 ^+11,000 B.P. Both fossils and wood were deposited contemporaneously in shallow-lake shell marls and swamp peat deposits of late Quaternary age. Pollen analysis indicates that this P. azael inhabited a Eucalyptus woodland.     

A new giant python from the Pliocene Bluff Downs Local Fauna of northeastern Queensland

Liasis dubudingala n. sp., described on the basis of isolated vertebrae from the Early Pliocene Bluff Downs Local Fauna, is the largest snake known from Australia. Dependance of vertebral proportions on intracolumnar position indicates that the fossil taxon can be excluded from the Morelia/Python clade. High neural spines suggest possible affinity with Liasis olivacea, whereas a posterior dentary fragment with small teeth is unlike L. olivacea and more similar to Liasis mackloti or species of Bothrochilus and Leiopython. As these extant species have all recently been treated as members of Liasis, the new species is assigned to that genus.     

Late Triassic megaspores from the Amery Group,Prince Charles Mountains,East Antarctica

Cantrill, D. J., & Drinnan, A. N., 1994:03:28. Late Triassic megaspores from the Amery Group, Prince Charles Mountains, East Antarctica. Alcheringa 18, 71–78. ISSN 0311-5518.

Megaspores referable to the genera Cabochonicus Batten & Ferguson 1987 and Minerisporites Potonié 1956 are a common component of the palaeoflora recovered from the Jetty Member within the Flagstone Bench Formation of the Amery Group. The known ranges of these two genera, in conjunction with the macrofloral remains, suggest a Late Triassic age. Two new species, Cabochonicus sinuosus and Minerisporites triangulatus, are described. Scanning electron microscopic examination of the spores indicates that standard palynological treatment of megaspores can result in sculptural degradation, possibly leading to incorrect generic assignment.     

Wood Pseudomorphs From Level I at Abric Romani,Barcelona, Spain

Abstract

Hollow impressions with sharp boundaries reflecting the morphologies of a tree trunk, long sticks, and diverse small wood fragments appeared embedded in the 46–49,000-year-old travertine platform of Level I at the Romani Rockshelter. Biodegradation of the wood may have occurred after a rapid overlaying of the bark with calcite concretions, generated by biogeochemical agents influenced by the favorable environment of the site.     

A new temnospondyl amphibian from the Lower Triassic of South America

A new temnospondyl from the Early Triassic Buena Vista Formation (Paraná Basin) in Uruguay is described. The specimen is represented by a skull table fragment which includes the left orbit, and, although fairly incomplete, shows close affinities with the basal temnospondyl clade (Dvinosaurus + Tupilakosauridae). Previously, members of this clade were only known from Upper Permian and Lower Triassic deposits from the Northern Hemisphere. The new specimen described herein together with a recent record from the Lower Triassic of South Africa (Karoo Basin), support the hypothesis of an invasion of members of the basal (Dvinosaurus + Tupilakosauridae) clade into Gondwana as early as the Late Permian.     

Early Miocene bivalves from the Cape Melville Formation,King George Island,West Antarctica

Seven species of marine bivalves, including six new taxa, are described from the Cape early Miocene Melville Formation which crops out on the Melville Peninsula, King George Island, West Antarctica. The bivalve assemblage includes representatives of the families Nuculidae, Ennucula frigida sp. nov., E. musculosa sp. nov.; Malletidae, Neilo (Neilo) rongelii sp. nov.; Sareptidae, Yoldia peninsularis sp. nov.; Limopsidae, Limopsis psimolis sp. nov.; Hiatellidae, Panopea (Panopea) sp. cf. P. regularis; and Pholadomyoida (Periploma acuta sp. nov.). Species studied come from four sedimentary sections measured in the upper part of the unit. Detailed morphologic features of nucloid and arcoid species are exceptionally well preserved and allow for the first time reconstruction of muscle insertions as well as dentition patterns of Cenozoic taxa. Known geological distribution of the species is in agreement with the early Miocene age assigned to the Cape Melville Formation. The bivalve fauna from Cape Melville Formation is the best known from Antarctic Miocene rocks, a time of complex geologic, paleogeographic and paleoclimatic changes in the continent. The new fauna introduces new taxonomic and palaeogeographic data that bear on the question of opening of sea gateways and distribution of Cenozoic biota around Antarctica.     

A palynological investigation of plesiosaur-bearing rocks from the Upper Cretaceous Tahora Formation,Mangahouanga, New Zealand

High-palaeolatitude plesiosaur, mosasaur and, more rarely, dinosaur fossils are well known from the Maungataniwha Sandstone Member of the Tahora Formation in Mangahouanga Stream, Hawkes Bay, New Zealand. A palynological investigation of strata exposed along Mangahouanga Stream and of transported boulders hosting vertebrate fossils reveals well-preserved assemblages dominated by terrestrial pollen and spores but also including marine dinoflagellate cysts in some samples. The palynofacies are strongly dominated by wood fragments including charcoal; one outcrop sample and the sample taken from a boulder hosting plesiosaur vertebrae contain entirely terrestrially derived palynoassemblages, suggesting a freshwater habitat for at least some of the plesiosaurs. The host unit spans the Santonian to lowermost Maastrichtian, while the key pollen taxa Nothofagidites senectus and Tricolpites lilliei, together with the dinocyst Isabelidinium pellucidum and the megaspore Grapnelispora evansii, indicate a late Campanian to early Maastrichtian age for the fossiliferous boulders. The palynoflora indicates a mixed local vegetation dominated by podocarp conifers and angiosperms with a significant tree-fern subcanopy. The presence of taxa with modern temperate distributions, such as Nothofagus (southern beech), Proteaceae and Cyatheaceae (tree-ferns), indicates a mild-temperate climate and lack of severe winter freezing during the latest Cretaceous, providing an ecosystem that most probably made it possible for polar dinosaurs to overwinter in this part of the world.     

Miocene wood from the LaTrobe Valley coal measures,Victoria, Australia

An initial study of a collection of fossil conifer wood is reported from the late early Miocene Yallourn Clays, an interseam unit intergrading into the base of the early to middle Miocene Yallourn seam of the LaTrobe Valley, Victoria in southeastern Australia. The fossil wood shares characteristics with the modem genera Dacrycarpus and Dacrydium. On the basis of contiguous, uniseriate tracheid pitting and 1–2 podocarpoid cross field pits, it is placed in the form genus Podocarpoxylon, and the new species P. latrobensis. The wood is compared with extant Podocarpaceae and other Australian fossil woods. Its ring anatomy is consistent with low temperature or rainfall seasonality in the early Miocene.     

Facing Climate Change: Andrea Juan's Visual Play with Science and the Sublime

Andrea Juan has responded to climate change in her art since 2002, highlighting the potential enjoyment of uncertainty and the pleasure of discovering this ecological crisis. Through an examination of El bosque invisible: Serie Antártica [The Invisible Forest: The Antarctica Series], 2010, this article will examine how Juan represents environmental transformations through her process, aesthetic choices, and work in Antarctica. Antarctica—an emblem of environmental change and advancements in scientific research—serves as one of the main stages for Juan's placement of colorful fabrics and cloth figures that are meant to represent specific natural phenomena connected to climate change. Juan's documentation of these scenes in videos and digital stills quotes the Romantic tradition of the sublime in landscape painting, the artist-traveller, and a heroic notion of scientific fieldwork, which exposes a continued desire for control despite our increasing knowledge of our limitations, as well as two principal means through which we understand climate change: science and the sublime. Furthermore, the pleasing quality of Juan's art, in spite of the crisis to which she alludes, aligns with contemporary trends that favor participation, pleasure and hope. This tendency itself exposes the uncertainty of art's role in the face of such crises.     

A new Middle Jurassic Chinese fossil clarifies the systematic composition of the Heterophlebioptera (Odonata: Trigonoptera)

Juraheterophlebia sinica, a new species of damsel-dragonfly, is described from the Middle Jurassic of China. Its fore- and hind wings in connection to the body allows comparison of the type genera of the families Erichschmidtiidae and Juraheterophlebiidae, respectively based on a forewing and a hind wing. Juraheterophlebiidae is a junior synonym of the Erichschmidtiidae. The new fossil confirms the previous attributions of Erichschmidtia and Juraheterophlebia to the clade Heterophlebioptera.     

DETERIORATION ASSESSMENT OF WATERLOGGED ARCHAEOLOGICAL LIGNOCELLULOSIC MATERIAL VIA 13C CP/MAS NMR*

This study investigates the residual chemical composition of waterlogged archaeological lignocellulosic material found in Greece. Hazelnut pericarps and oak wood found in a 16th‐century wreck, along with endocarps of olives dated at 300 bc , were examined. ¹³C CP/MAS NMR was applied to compare fresh and waterlogged archaeological materials. Results show qualitative alterations in their composition. The virtual absence of peaks at ~21 ppm and ~173 ppm, corresponding to hemicelluloses in all archaeological materials, indicates that these constituents can be an important indicator in assessing the type and degree of deterioration.     

Viking age wood resources at Argisbrekka,Faroe Islands

A project is described concerning the examination of wood from two settlements on Eysturoy. Argisbrekka is a seasonally occupied inland settlement radiocarbon‐dated to the 9th–11th centuries, while Toftanes is a year‐round coastal settlement from the 9th–10th centuries. Preliminary investigations of wood from houses and refuse layers at Argisbrekka demonstrate the utilization of three resources: (a) local vegetation of Juniperus, tree Betula and heathland dwarf shrubs, (b) driftwood Picea and Larix, (c) imported wood Pinus and Quercus. The impact of man and husbandry on the vegetation probably resulted in the extinction of tree Betula and the almost total disappearance of Juniperus.     

Umkomasia (megasporophyll): part 1 of a reassessment of Gondwana Triassic plant genera and a reclassification of some previously attributed

The genus Umkomasia, a megasporophyll, belonging to the pteridosperms (seed ferns) in the family Umkomasiaceae (Corystospermaceae), is reassessed comprehensively worldwide. All previous records are analysed. Certain fertile structures previously attributed are reclassified. Umkomasia is shown to be restricted to the Triassic of Gondwana where it is associated with the genus Pteruchus, a microsporophyll, and the genus Dicroidium, a vegetative leaf. It is well represented from Argentina, Australia and southern Africa where the Molteno Formation is by far the most comprehensively sampled with eight species described. Two specimens from the upper Permian of India attributed to Umkomasia are reclassified as cf. Arberiopsis sp. A whorled fertile structure from Antarctica, previously assigned to Umkomasia, is reclassified in a new genus as Axsmithia uniramia. Another compression fossil and the permineralized Umkomasia resinosa remain as valid records from Antarctica. The material described as Umkomasia from the Triassic of China is reclassified as Stenorachis asiatica. The Lower Jurassic record from Germany is placed in a new genus as Kirchmuellia franconica. The records of Umkomasia sp. from the Rhaetic of Germany are reclassified as cf. Kirchmuellia sp. and the single specimen from the Jurassic of Libya as genus et sp. indet. The Lower Cretaceous record from Mongolia has been reclassified by other researchers as Doylea mongolica. A pictorial key to Umkomasia species is provided, geographic and stratigraphic distributions are tabulated.     

Cainozoic euphorbiacean wood from the Canning Basin,Western Australia

A new species of fossil wood is described, Bridelioxylon canningense Bamford & McLoughlin, belonging to the Phyllanthoideae group of the Euphorbiaceae. The woods occur in indurated sandstones and conglomerates preserved in palaeochannels incised into the Upper Permian Condren Sandstone in the Landrigan Cliffs, northern Canning Basin, Western Australia. Based on the presence of the dicotyledonous woods and the geomorphological setting of the palaeochannel, a Palaeogene age is suggested for the host rocks. This is the first record of fossil euphorbiacean wood in Australia; pollen has been previously recorded. The fossil wood is most closely comparable to extant members of Bridelia that currently occupy the warmer and wetter parts of Australia.     

Who goes there? Science, fiction, and belonging in Antarctica

The implications of the ATS regime on Antarctica have been profound, both structuring the possibilities for states to engage Antarctica, while limiting those very engagements to those directly related to science. State-run science has in many ways solved the problem of Antarctica's resistance to capital development and provided a safe course for national rivalry. Yet science has not always been seen as the sole convener of Antarctic activity. Tracing three versions of a story of resistance to an alien invasion of the pole – John Campbell's ‘Who Goes There?’ (1935), and its two filmic remakes, Christian Nyby's The Thing From Another World (1951) and John Carpenter's The Thing (1981), in relation to Richard E. Byrd's Antarctic exploration career, this essay considers US strategies for incorporating Antarctic territory into national and global imaginaries.     

Millerocaulis tekelili sp. nov., a new species of osmundalean fern from the Aptian Cerro Negro Formation (Antarctica)

Vera, E.I. iFirstarticle. Millerocaulis tekelili sp. nov., a new species of osmundalean fern from the Aptian Cerro Negro Formation (Antarctica). Alcheringa, 1–10. ISSN 0311-5518.

Ezequiel Ignacio Vera [evera@macn.gov.ar] División Paleobotánica, Museo Argentino de Ciencias Naturales 'Bernardino Rivadavia', Av. Angel Gallardo 470, C1524DJR, Buenos Aires, Argentina. Also affiliated with Área de Paleontología, Departamento de Ciencias Geológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón II, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina. Received 29.10.2010, revised 14.3.2011; accepted 24.3.2011.

A new species of the osmundalean fossil morphogenus Millerocaulis Tidwell emend. Vera, Millerocaulis tekelili sp. nov. is defined, based on several permineralized stems recovered from exposures of the Lower Cretaceous Cerro Negro Formation on Livingston Island, South Shetland Islands, Antarctica. This new species is characterized by the presence of an ectophloic–dictyoxylic siphonostele, inner parenchymatic and outer sclerotic cortices, heterogeneous sclerotic ring in the petiole bases, absence of sclerenchyma associated with the petiolar xylem trace, petiolar inner cortex with sclerenchyma strands and stipular wings having a large sclerenchyma bundle and several smaller ones. The presence of non-homogeneous sclerotic rings in the petiole bases allows this new species to be clearly distinguished from other Antarctic Millerocaulis, and suggests that it may represent an intermediate form in the evolutionary lineage leading from Millerocaulis to subgenus Claytosmunda of Osmunda.     

Phylogenetic implications of macropodid (Marsupialia: Macropodoidea) posteranial remains from Miocene deposits of Riversleigh,northwestern Queensland

A new sthenurine taxon, Rhizosthenurus flanneryi gen. et sp. nov. from middle late Miocene deposits of Riversleigh, northwestern Queensland, is established on the basis of material previously assigned to Bulungamayinae. Postcranial remains belonging to an indeterminate basal macropodid are described. Cladistic analysis of 50 discrete postcranial characters coded for 16 ingroup and two outgroup taxa suggests that R. flanneryi is the most plesiomorphic member of a clade containing the late Miocene macropodid Hadronomas puckridgi and crown-group sthenurines. The indeterminate basal macropodid is placed as the immediate sister taxon to the bulungamayine Ganguroo bilamina and a monophyletic clade containing macropodines and sthenurines. This arrangement supports consideration of bulungamayines as ancestral to other macropodids and suggests that macropodines and sthenurines are monophyletic. However, the possibility of a diphyletic origin for Macropodinae and Sthenurinae from within Bulungamayinae cannot be dismissed.     

Cretaceous avian remains from Patagonia shed new light on the early radiation of birds

The anatomy of a new articulated enantiornithine bird skeleton from the Late Cretaceous of Patagonia clearly indicates a capacity for powered flight, approaching that of modern birds. Enantiornithines possess some of the synapomorphies of the Ornithurae, although they retain plesiomorphic states for many other characters, mainly in the hind limb. Such a mosaic character combination suggests a sister-group relationship between Enantiornithes and Ornithurae. Derived features of the pectoral girdle are here considered as diagnostic for a major avian clade, the Ornithopectae, comprising all known birds other than Archaeopteryx. The combination of derived and primitive traits in the fore and hind limbs and their girdles in early ornithopectines reflects mosaic evolution, with flight-related modifications of the fore limb and pectoral girdle preceding those in the hind limb and pelvic girdle.     

Archaeocyaths from Yorke Peninsula,South Australia and archaeocyathan Early Cambrian zonation

Zhuravlev, A. Yu., & Gravestock, D. I., 1994:03:28. Archaeayaths from Yorke Peninsula, South Australia and archaeocyathan Early Cambrian zonation. Alcheringa 18, 1–54. ISSN 0311-5518.

Two assemblages of archaeocyaths are documented from Lower Cambrian outcrops and drillholes on Yorke Peninsula. South Australia. The older assemblage (11 species) occurs in the uppermost Kulpara Formation and conformably overlying basal Parara Limestone, and is equivalent to Lower Faunal Assemblage II in the Flinders Ranges. The younger assemblage (28 species plus Acanthhcyathus and Rodiocyathus) occurs in the Koolywurtie Member near the top of the Parara Limestone. Equivalent taxa are widespread in the Flinders Ranges, western New South Wales and Antarctica. Archaeocyathan distribution is now sufficiently well known to propose three assemblage zones and two informal assemblages for regional correlation. No new taxa have been added, but Erugatocyathus scutatus (Hill) and Pycnoidocyathus latiloculatus (Hill), hitherto known only from Antarctica, are found in the upper assemblage on Yorke Peninsula. Irregular archaeocyathan systematics are discussed, the ontogeny of Archaeopharetra irregularis (Tylor) clarified, and Kruseicnema Debrenne. Gravestock & Zhuravlev, represented by K. gracilis (Gordon), is fully described.