Ordovician stromatoporoids from Tasmania

The Hunter Siltstone near Grenfell, New South Wales, contains a rich Upper Devonian fish fauna including the sinolepid Grenfellaspis and the new antiarchs Bothriolepis grenfellensis sp. nov. and Remigolepis redcliffensis sp. nov. Bothriolepis grenfellensis sp. nov. is the first bothriolepid species described from N.S.W., and R. redcliffensis sp. nov. is the first species of Remigolepis described from Australia. Traditionally, the Hunter Siltstone was considered to be uppermost Famennian or earliest Carboniferous in age based on the presence of Grenfellaspis, and the related taxon Sinolepis, which is known from the Wutung and Sanmentan formations of southeastern China. However, available data indicates the Hunter Siltstone may be early Famennian in age. Ongoing work suggests that all Famennian Bothriolepis from N.S.W., including B. grenfellensis, possess a trifid preorbital recess, but differ in other aspects of headshield morphology. In North China, the Famennian Zhongning Formation contains six species of Remigolepis and a species of Sinolepis. However, R. redcliffensis does not show any similarity to these species beyond those of Remigolepis as a whole.     

Acanthodian,onychodontid and osteolepidid fish from the middle-upper Taemas Limestone (Early Devonian), Lake Burrinjuck,New South Wales

A meagre ischnacanthid acanthodian fauna, known from fragmentary dentigerous jawbones from Lake Burrinjuck, Yass district, New South Wales, consists of three taxa: Taemasacanthus narrengullenensis, Taemasacanthus cooradigbeensis and an indeterminate ischnacanthid. The fossils are from three Early Devonian (Emsian) units at Taemas: the Bloomfield Limestone Member, the Currajong Limestone Member and the Warroo Limestone Member, which constitute the middle-upper parts of the Taemas Limestone (Murrumbidgee Group); and from Unit 6 of the ‘Upper Reef formation’ at Wee Jasper. Whereas ischnacanthid acanthodian remains are increasingly rarer in the higher levels of the Taemas Limestone, remains of onychodontid and osteolepidid fishes are relatively abundant; Onychodus yassensis sp. nov., Onychodus sp. and isolated osteolepidid teeth are locally common.     

Fixation of the type species of the genus Protoretepora de Koninck, 1878 (Bryozoa,Fenestrata)

Wyse Jackson, P.N., Reid, C.M. & McKinney, F.K., iFirst article, 2011. Fixation of the type species of the genus Protoretepora de Koninck, 1878 (Bryozoa, Fenestrata). Alcheringa, 1–2. ISSN 0311-5518.

The type species of the Palaeozoic bryozoan genus Protoretepora de Koninck, 1878 was originally fixed as Fenestella ampla Lonsdale in Darwin, 1844, but this taxon has been shown to belong to the bryozoan genus Parapolypora Morozova & Lisitsyn, 1996 Morozova, I. P. and Lisitsyn, D. V. 1996. Revision of the genus Polypora. Paleontologicheskii Zhurnal, 1996(4): 38–47. [English translation: Paleontological Journal30(5), 530–541] [Google Scholar]. The original type species designation for Protoretepora de Koninck, 1878 is set aside, and in accordance with Article 70.3 of the International Code of Zoological Nomenclature (4th edition, 1999) the nominal species Protoretepora crockfordae Wyse Jackson, Reid & McKinney, 2011 from the Permian of Tasmania, Australia is herein fixed as the type species.     

Acaste (Trilobita: Phacopina) from the Early Devonian of Tasmania

Edgecombe, G.D. March 2007. Acaste (Trilobita: Phacopina) from the Early Devonian of Tasmania. Alcheringa 31, 59-66. ISSN 0311-5518.

The widespread Siluro-Devonian acastid trilobites Acaste and Acastella are known from few occurrences in Australasia, these being confined to Lochkovian strata in Victoria and New Zealand. A new species, Acaste andersoni, is described from a correlative of the Bell Shale near St Valentines Peak in north-western Tasmania. Acaste supplements the biogeographic links between the Early Devonian faunas of New Zealand, Victoria and Tasmania.

Gregory D. Edgecombe [greged@austmus.gov.au], Australian Museum, 6 College Street, Sydney, NSW 2010, Australia; received 2.3.2005, revised 6.4.2005.     

A new Llanvirnian Isograptus from the D. murchisoni Shales of Abereiddy Bay,Wales

Isograptus ovatus davidensis subsp. nov. is described from the D. murchisoni Shales of Abereiddy Bay, Wales. This discovery gives further support to the correlation of the murchisoni Zone with the upper part of the Darriwil Stage of Victoria.     

Utilizing U–Pb CA-TIMS dating to calibrate the Middle to Late Jurassic spore-pollen zonation of the Surat Basin,Australia to the geological time-scale

Wainman, C.C., Hannaford, C., Mantle, D. & McCabe, P.J., April.2018. Utilizing U–Pb CA-TIMS dating to calibrate the Middle to Late Jurassic spore-pollen zonation of the Surat Basin, Australia to the geological time-scale. Alcheringa XX, xx-xx.

Spore-pollen palynostratigraphy is commonly used to subdivide and correlate Jurassic continental successions in eastern Australia and thus aid the construction of geological models for the petroleum and coal industries. However, the current spore-pollen framework has only been tenuously calibrated to the geological time-scale. Age determinations are reliant on indirect correlations of ammonite and dinoflagellate assemblages from New Zealand, the North West Shelf of Australia and Southeast Asia to the standard European stages. New uranium-lead chemical abrasion thermal ionization mass spectrometry (U–Pb CA-TIMS) dates from 19 tuff beds in the Middle–Upper Jurassic Injune Creek Group of the Surat Basin enables regional spore-pollen palynostratigraphic zones to be precisely dated for the first time. These results show the base of the APJ4.2 and APJ4.3 subzones are similar in age to previous estimates (Middle Jurassic, Bathonian) from indirect palynostratigraphic correlation. However, the base of the APJ5 Zone and the APJ6.1 Subzone may be somewhat younger than previously estimated, possibly by as much as 2.5 and 4.2 Myrs, respectively. The continued utilization of U–Pb CA-TIMS dates will further refine the absolute ages of these zones, improve the inter- and intra-basinal correlation of Middle–Upper Jurassic strata in eastern Australian basins and greatly enhance intercontinental correlations.

Carmine Christopher Wainman [carmine.wainman@adelaide.edu.au] and Peter James McCabe [peter.mccabe@adelaide,edu.au] Australian School of Petroleum, University of Adelaide, SA, 5005, Australia; Carey Hannaford [carey.hannaford@mgpalaeo.com.au] and Daniel Mantle [dan.mantle@mgpalaeo.com.au] MGPalaeo Pty Ltd, 5 Arvida Street, Malaga, WA, 6090, WA, Australia.     

Stromatolite recognition in ancient rocks: an appraisal of irregularly laminated structures in an Early Archaean chert-barite unit from North Pole,Western Australia

The word ‘stromatolite’ should only be applied to organosedimentary structures predominantly accreted by sediment trapping, binding and/or in situ precipitation as a result of the growth and metabolic activities of benthic, principally prokaryotic, micro-organisms. Structures of uncertain origin that resemble stromatolites should be called ‘stromatoloids’. This cautious approach would eliminate the currently common assumption that structures with mesoscopic morphological similarities to microbially accreted sedimentary structures must be biogenic, a misconception that hampers investigations into the antiquity of life.

A hierarchical series of meso- and microstructural attributes of stromatolites can be used to assign gradually increasing probabilities of biogenicity to stromatoloids. This method is particularly useful for interpreting ancient noncolumnar stromatoloids with poor microstructural preservation. In a range of Early Archaean pseudocolumnar, nodular and stratiform stromatoloids from North Pole studied using this method, none could be proved to be stromatolites and only a few are probable or possible stromatolites. As these stromatoloids closely resemble previously reported structures from North Pole interpreted as stromatolites, we consider that the evidence for the existence of life c. 3500 my ago at North Pole is less definitive than previously supposed.     

Marcusodictyon Bassler from the Lower Ordovician of Estonia: not the earliest bryozoan but a phosphatic problematicum

Marcusodictyon priscum (Bassler 1911) from the Tremadocian Ungulite Sandstone (A2) of Jegelecht Falls, Estonia, is redescribed following SEM study of type and other specimens. The fossil consists of a polygonal network of low ridges known to exist only on the exterior surfaces of valves of the inarticulate brachiopod Obolus. Electron microprobe analysis demonstrates that, like its host substratum, Marcusodictyon is composed of calcium phosphate. This, together with the detailed morphology and dimensions of the ridge system, is used to negate Bassler's assignment of the genus to the ctenostome Bryozoa. Instead Marcusodictyon resembles the Silurian problematicum Gochtia Eisenack. The inferred growth pattern of Marcusodictyon suggests that it may have been a symbiont of a living brachiopod.     

Migration,Geographies of Marginality and Informality—Impacts on Upper and Lower Ends of Urban Systems in the North and South

Since the onset of post-industrialism, the research focus in the developed world has increasingly shifted to the role of the information and communication technology, knowledge workers and the creative sector in the global economy. It has led to what could be described as an iceberg approach to economic research. In this approach, the focus is primarily on what happens in the part of the global economic iceberg above the waterline—the “clean”, “fast-moving”, “technologically advanced” elements of the global economy. However another element of the global economy, the informal sector, is growing at an alarming rate in cities in both the developed and developing worlds. These activities are unobtrusively operating in a part of the iceberg below the waterline that receives relatively little attention from the research community. The purposes of this paper are to demonstrate how the information networks created in the iceberg above the waterline are being used by a growing section of the society in the developing world in order to reach first-world destinations. It shows how informality is changing the urban landscape in first-world cities where large concentrations of non-Western populations occur. The paper then shifts its attention to the overwhelmingly informally driven economies of African cities and outlines the inappropriateness of standard economic measures to accurately portray conditions there.