A possible succineid land snail from the Lower Cretaceous non-marine deposits of the Griman Creek Formation at Lightning Ridge,New South Wales

A diverse non-marine molluscan fauna has been recorded from the Lower Cretaceous (middle–upper Albian), low-energy, fluvial sediments of the Griman Creek Formation at Lightning Ridge in northern New South Wales. We describe a novel addition to this assemblage—a probable pulmonate gastropod that manifests features (including shell with an inflated body whorl, expansive aperture, and reduced spire/whorl count) consistent with Succineidae, an extant cosmopolitan family of terrestrial snails. The fossils are assigned to a new genus and species (Suratia marilynae), distinguishable from existing taxa by a combination of traits: shell with sculpturing limited to fine growth lines only, lunate body whorl with a rounded periphery, markedly flattened spire (comprising up to two whorls), which is almost flush with the apical surface and delineated by a deeply impressed sutural ‘gutter,’ and presence of both a broad columellar plait and distinct columellar fold. The new taxon apparently constitutes the oldest pulmonate remains recorded from Australasia, and extends the known stratigraphical range of succineids back to the Lower Cretaceous in the Southern Hemisphere.     

Microdictyon plates from the lower Cambrian Ajax Limestone of South Australia: Implications for species taxonomy and diversity

A small assemblage of isolated Microdictyon plates is described from the lower Cambrian Ajax Limestone, Mt Scott Range (Flinders Ranges), South Australia. Microdictyon plates are primarily known from single, isolated, perforated phosphatic sclerites; only one species (M. sinicum) from the Chengjiang Lagerstätte is known from soft-bodied preservation of the complete organism. The isolated plates from South Australia display a wide range of morphologies potentially reflecting: 1, considerable diversification within the group at this time; 2, extensive intraspecific morphological variation; 3, different plate morphotypes along the trunk of the animal; or 4, significant ontogenetic variation in successive growth stages. The South Australian specimens are similar to several individual sclerites described from other Cambrian palaeocontinents, but appear closest to faunas described from South China. Problems associated with the taxonomy of isolated Microdictyon plates are discussed, including the lack of knowledge associated with intraspecific and/or ontogenetic variability and how individual plate morphology may relate to size or relative position along the length of the complete organism.     

Middle Ordovician brachiopods from the Stairway Sandstone,Amadeus Basin,central Australia

Jakobsen, K.G., Brock, G.A, Nielsen, A.T., Topper, T.P. & Harper, D.A.T., 2013. Middle Ordovician brachiopods from the Stairway Sandstone, Amadeus Basin, central Australia. Alcheringa. ISSN 0311–5518.

Middle Ordovician brachiopod faunas from the Amadeus Basin, central Australia are poorly known. The Darriwilian Stairway Sandstone was sampled stratigraphically for macrofossils in order to provide new information on marine benthic diversity in this clastic-dominated, shallow-water palaeoenvironment along the margin of northeastern Gondwana. The brachiopods from the Stairway Sandstone are of low diversity and represent ca 9% of the entire shelly fauna. Five brachiopod taxa are described from the Stairway Sandstone; all are endemic to the Amadeus Basin at species level. Two new species, Amadeuphyla joanae gen. et sp. nov. and Paralenorthis luritjaorum sp. nov., are described. Unweighted cladistic analysis based on 20 characters places the new genus Amadeuphyla within the Taffinae.

Kristian G. Jakobsen [kgjakobsen@snm.ku.dk] Geological Museum, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5–7, DK-1350 Copenhagen, Denmark & Department of Biological Sciences, Macquarie University, New South Wales 2109, Australia. Glenn A. Brock [glenn.brock@mq.edu.au] Department of Biological Sciences, Macquarie University, New South Wales 2109, Australia. Arne T. Nielsen [arnet@snm.ku.dk] Geological Museum, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5–7, DK-1350 Copenhagen, Denmark. Timothy P. Topper [timothy.topper@snm.ku.dk] Geological Museum, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5–7, DK-1350 Copenhagen, Denmark. David A. T. Harper [david.harper@durham.ac.uk] Geological Museum, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5–7, DK-1350 Copenhagen, Denmark & Department of Earth Sciences, Durham University, Durham, UK. Received 14.6.2013; revised 25.9.2013; accepted 8.10.2013.     

Spondylodendron pranabii—the dominant lycopsid of the late Mississippian vegetation of the Kashmir Himalaya

Cleal, C.J., Bhat, G.M., Singh, K.J., Dar, A.M., Saxena, A. & Chandra, S., February 2016. Spondylodendron pranabii—the dominant lycopsid of the late Mississippian vegetation of the Kashmir Himalaya. Alcheringa 40, xxx–xxx. ISSN 0311-5518.

The Sepukhovian fossil floras of the northern margins of Gondwana, on the shores of the Palaeotethys, are dominated by remains of an eligulate, mainly monopodial lycopsid with persistent leaves. The stems show considerable morphological and preservational variation that has historically resulted in the fossils having been assigned to many fossil-species and -genera. However, there is now clear evidence that this simply reflects variation within a single fossil-species, reflecting biological variation and the effects of variable taphonomy, for which the correct taxonomic name is Spondylodendron pranabii (Pal) comb. nov. Part of this morphological variation might have been due to variations in growth rate during the life of the individual plants, which in turn might reflect stressed growing conditions in a wetland habitat. The systematic position of Spondylodendron remains uncertain, owing to the lack of unequivocal evidence of reproductive structures, but it might have affinities with the Sublepidodendraceae.

Christopher J. Cleal [chris.cleal@museumwales.ac.uk], Department of Natural Sciences, National Museum Wales, Cathays Park, Cardiff CF10 3NP, UK; G.M. Bhat [bhatgm@jugaa.com] and A.M. Dar, Department of Geology, University of Jammu, Jammu, India; Kamal Jeet Singh, [kamaljeet31@hotmail.com] and Anju Saxena [anju_saxena2002@yahoo.co.in], Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, (U.P.) India; Shaila Chandra, Flat Number 105, Beverly Park Apartment 422, New Hyderabad, Lucknow-226007, (U.P.) India.     

Oldest meiolaniid turtle remains from Australia: evidence from the Eocene Kerosene Creek Member of the Rundle Formation,Queensland

Poropat, S.F., Kool, L., Vickers-Rich, P. &; Rich, T.H., September 2016. Oldest meiolaniid turtle remains from Australia: evidence from the Eocene Kerosene Creek Member of the Rundle Formation, Queensland. Alcheringa 41, XX–XX. ISSN 0311-5518.

Fossil meiolaniid turtles are known only from South America and Australasia. The South American record is restricted to the Eocene, and comprises two genera: Niolamia and Gaffneylania. The Australasian meiolaniid record is more diverse, with three genera known (Ninjemys, Warkalania and Meiolania); however, the oldest known specimens from this continent are significantly younger than those from South America, deriving from upper Oligocene sediments in South Australia and Queensland. Herein, we describe the oldest meiolaniid remains found in Australasia to date. The specimens comprise a posterior peripheral, a caudal ring, and an osteoderm, all of which derive from the middle–upper Eocene Rundle Formation of The Narrows Graben, Gladstone, eastern Queensland. Despite their fragmentary nature, each of these specimens can be assigned to Meiolaniidae with a high level of confidence. This is particularly true of the partial caudal ring, which is strongly similar to those of Niolamia, Ninjemys and Meiolania. The extension of the Australasian meiolaniid record to the Eocene lends strong support to the hypothesis that these turtles arose before South America and Australia detached from Antarctica, and that they were consequently able to spread across all three continents.

Stephen F. Poropat*^? [stephenfporopat@gmail.com], Australian Age of Dinosaurs Natural History Museum, The Jump-Up, Winton, Queensland 4735, Australia; Lesley Kool*^? [koollesley@gmail.com] and Thomas H. Rich [trich@museum.vic.gov.au], Melbourne Museum, 11 Nicholson St, Carlton, Victoria 3053, Australia; Patricia Vickers-Rich [pat.rich@monash.edu], Monash University, Wellington Rd, Clayton, Victoria 3800, Australia. *These authors contributed equally to this work. ^?Also affiliated with Monash University, Wellington Rd, Clayton, Victoria 3800, Australia.     

Triassic palynostratigraphy and palynofloral provinces: evidence from southern Xizang (Tibet), China

Peng, J., Li, J., Slater, S.M., Li, W., Zhu, H. & Vajda, V. October 2017. Triassic palynostratigraphy and palynofloral provinces: evidence from southern Xizang (Tibet), China. Alcheringa 42, 67–86. ISSN 0311-5518.

Palynological analysis was carried out on Middle to Upper Triassic strata from Tulong, Nyalam County, southern Xizang (Tibet), China. Well-preserved miospore (pollen and spore) assemblages and sparse acritarch occurrences were identified. We recognized four formal and one informal biozones based on stratigraphically important taxa and compositional changes through the succession, in ascending order: the Triplexisporites Interval Zone (Anisian), the Staurosaccites quadrifidus Taxon-range Zone (upper Anisian to lower Norian), the Striatella Interval Zone (lower Norian), the Craterisporites rotundus Taxon-range Zone (middle to upper Norian) and the informal ‘Dictyophyllidites harrisii zone’ (Rhaetian). The zonation was supported by marine fossils (e.g., ammonoids and conodonts), and compositional similarity between the zones was examined using non-metric multidimensional scaling (NMDS). Correlation with other representative palynological sequences across Gondwana was also conducted. The presence of miospore taxa not previously recovered from the Late Triassic North and South China palynofloral provinces (e.g., Ashmoripollis reducta, Craterisporites rotundus, Enzonalasporites vigens, Minutosaccus crenulatus, Samaropollenites speciosus and Staurosaccites quadrifidus) calls for a new province in southwestern China, i.e., the Southern Xizang Province. It is proposed here that the modern expression of the northern boundary runs along the Yarlung Zangbo Suture, the remnant of the Tethys that separated the Indian Plate (southern Xizang) and the Lhasa Block during the Late Triassic. This new palynofloral province comprises typical elements of the Onslow Microflora, indicating the need for an extension of this microflora in southern Xizang, China.

Jungang Peng [jgpeng@nigpas.ac.cn], Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China, University of Chinese Academy of Sciences, Beijing 100049, China, Department of Palaeobiology, Swedish Museum of Natural History, Stockholm 104 05, Sweden; Jianguo Li* [jgli@nigpas.ac.cn], Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; Wenben Li [wenbenli@126.com], Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; Sam M. Slater [sam.slater@nrm.se], Vivi Vajda [vivi.vajda@nrm.se], Department of Palaeobiology, Swedish Museum of Natural History, Stockholm 104 05, Sweden; Huaicheng Zhu [hczhu@nigpas.ac.cn], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China.     

Morphology,palaeoecology and taphonomy of the Devonian mitrate Placocystella langei from Paraná Basin,Brazil

Sandro Marcelo Scheffler, Rodrigo Scalise, Horodyski & Elvio Pinto, Bosetti, 2018. Morphology, palaeoecology and taphonomy of the Devonian mitrate Placocystella langei from Paraná Basin, Brazil. Alcheringa 43, 228–240. ISSN 0311-5518.

The original holotype and paratypes of the stylophoran mitrate Placocystella langei (Echinodermata) are definitively lost. A neotype is designated here, based on new material collected in the marine Devonian strata of the Apucarana Sub-basin, Paraná, Brazil. Placocystella langei was the first species of Stylophora to be identified in Devonian basins from Brazil. Its range extends from the late Emsian to early Givetian. Taphonomic data indicate that P. langei specimens were preserved in a storm-influenced, transitional offshore environment, and that skeletal remains were few exposed at the water–sediment surface. Considering that the specimens do not exhibit evidence of reworking, it is possible that their final burial was rapid and definitive, which facilitated their almost complete preservation. Finally, taphonomic, diagenetic and sedimentologic data all suggest a shallow infaunal habit for Placocystella langei.

Sandro Marcelo Scheffler [schefflersm@mn.ufrj.br] Departamento de Geologia e Paleontologia, Laborat orio de Paleoinvertebrados (LAPIN), Museu Nacional—UFRJ, Parque Quinta da Boa Vista, s/n, São Cristóvão 20940040, Rio de Janeiro, RJ, Brasil; Rodrigo Scalise Horodyski* [rhorodyski@unisinos.br] Graduate Program in Geology, Vale do Rio dos Sinos University, Av. Unisinos, 950, Cristo Rei, 93022-000 São Leopoldo, RS, Brasil; Elvio Pinto Bosetti [elviobosetti@gmail.com] Departamento de Geociências, Universidade Estadual de Ponta Grossa, Av. Carlos Cavalcanti 9.500, Uvaranas, 84010-919, Ponta Grossa, Paran a, Brazil.     

Shelly fauna from the Cambrian (Miaolingian,Guzhangian) Shannon Formation and the SPICE event in the Amadeus Basin,Northern Territory

Smith, P.M., Brock, G.A. & Paterson J.R. 20 September 2019. Shelly fauna from the Cambrian (Miaolingian, Guzhangian) Shannon Formation and the SPICE event in the Amadeus Basin, Northern Territory. Alcheringa 44, 1–24. ISSN 0311-5518

A low-diversity assemblage of linguliformean brachiopods, hyoliths, molluscs, bradoriid arthropods and echinoderms (ten taxa in total) is documented from the upper Shannon Formation (Cambrian, Miaolingian, Guzhangian; Mindyallan) in the Ross River Syncline and Todd River Anticline area, NE Amadeus Basin, central Australia. Taxa described include: the linguliformean brachiopods Treptotreta jucunda Henderson & MacKinnon, 1981, Opisthotreta sp., Stittia? sp., an undetermined acrotretid and an undetermined linguloid; the molluscs Kobayashiella? heritagensis Webers, Pojeta & Yochelson, 1992 (a paragastropod), and Apoptopegma joyceae sp. nov. (a rostroconch); the bradoriid Mongolitubulus sp.; Hyolithida gen. et sp. indet.; and isolated echinoderm plates. All fauna (including previously documented trilobites) from the upper Shannon Formation disappear at the beginning of a ～5‰ positive shift in δ¹³C, identified as the Steptoean Positive Isotopic Carbon Excursion (SPICE). Despite previous links between SPICE and a global extinction, as well as the disappearance of all faunal elements in the uppermost Shannon Formation, certain taxa reported herein range through the event elsewhere in the world. The occurrence of Treptotreta jucunda and Kobayashiella? heritagensis in younger (Furongian) deposits indicates these species survived the SPICE extinction event. This study advocates for more systematic and comprehensive sampling through stratigraphic intervals where the SPICE event occurs, especially for range data of complete faunas (rather than individual taxonomic groups), to facilitate a more complete picture of diversity trends through this important phase.

P.M. Smith* [patrick.smith@austmus.gov.au], Palaeontology Department, Australian Museum Research Institute, Sydney, New South Wales, 2010, Australia; G.A. Brock [glenn.brock@mq.edu.au], Department of Biological Sciences, Macquarie University, Sydney, New South Wales, 2109, Australia. J.R. Paterson [jpater20@une.edu.au], Palaeoscience Research Centre, School of Environmental and Rural Science, University of New England, Armidale, New South Wales, 2351, Australia. *Also affiliated with: Department of Biological Sciences, Macquarie University, Sydney, New South Wales, 2109, Australia.     

First record of the ichthyodectiform fish Xiphactinus (Teleostei) from Patagonia,Argentina

Abstract

We report the first record of the genus Xiphactinus from southern South America. The recovered fossil material consists of an associated maxilla and abdominal vertebra, probably derived from latest Maastrichtian marine deposits of the Salamanca Formation in Chubut Province, Argentina. Xiphactinus has been widely reported from Late Cretaceous strata throughout the Northern Hemisphere, although to date, equivalent Southern Hemisphere occurrences include only a single specimen from Venezuela. Our new discovery thus indicates that Xiphactinus had a much more cosmopolitan distribution, encompassing the southern paleolatitudinal extremities of South America during the terminal Cretaceous.

Julieta J. De Pasqua [julietadepasqua@gmail.com], Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, Av. Ángel Gallardo, 470, C1405DJR, Buenos Aires, Argentina;

Federico L. Agnolin [fedeagnolin@yahoo.com.ar], Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, Av. Ángel Gallardo, 470, C1405DJR, Buenos Aires, Argentina. CONICET; Fundación de Historia Natural ‘Félix de Azara’, Departamento de Ciencias Naturales y Antropología, Universidad Maimónides; Hidalgo 775 piso 7, C1405BDB, Buenos Aires, Argentina;

Sergio Bogan [sergiobogan@yahoo.com.ar], Fundación de Historia Natural ‘Félix de Azara’, Departamento de Ciencias Naturales y Antropología, Universidad Maimónides; Hidalgo 775 piso 7, C1405BDB, Buenos Aires, Argentina.