On the Middle Cambrian agnostoid species Agnostus fallax Linnarsson 1869

The types and other specimens of Agnostus fallax Linnarsson 1869 are examined and reinterpreted. It is shown that the application of this specific name to many specimens from around the world is largely in error. The species is considered sufficiently different from the type species of Peronopsis, P. integra (Beyrich, 1845) to warrant erection of a new genus Axagnostus with A. fallax as the type species.     

Nothofagus macrofossils from the Tertiary of Tasmania

Leaves assignable to Nothofagus from two fossil deposits in Tasmania represent the first macrofossils of this genus from the Tertiary in southeastern Australia. One fossil species, N. johnstonii, is closely related to the extant Australian species N. cunninghamii while the other fossil species, N. tasmanica, has very close affinites with the extant Australian species N. moorei. All four of these species are closely interrelated. The pollen type produced by the fossil species is unknown, since all three types are present in the microfloras. However, both N. cunninghamii and N. moorei produce N. menziesii-type pollen. The macrofossils confirm the conclusion from pollen studies that evolution in Nothofagus has occurred very slowly.     

The Late Cambrian trilobite Hamashania from Korea

The Late Cambrian trilobite genus Hamashania Kobayashi, 1942a has hitherto been poorly understood and is herein revised based on well-preserved specimens from Korea. Platysaukia Kobayashi, 1960 and Goumenzia Guo & Duan, 1978 are treated as junior synonyms of Hamashania. Hamashania comprises only two species, H. pulchera Kobayashi, 1942a and Pterocephalus busiris Walcott, 1905, and is restricted to North Chinaand Korea. The new genus Pacootasaukia is proposed to accommodate the Australian species Platysaukia jokliki Shergold, 1991 as type species, and Platysaukia tomichi Shergold, 1991, which are so distinct that they cannot be included within Hamashania. The generic concept of Mareda Kobayashi, 1942b, which was often confused with Hamashania, is confined to the type material.     

Biostratigraphic potential of Middle Cambrian hyoliths from the eastern Georgina Basin

Fourteen hyolith taxa are documented from the Middle Cambrian (Templetonian to Floran) of the eastern (Queensland) portion of the Georgina Basin, Australia, as a contribution toward a prospective Australian Cambrian hyolith biozonation. The described fauna is from the Beetle Creek Formation (including Monastery Creek Phosphorite Member) and Gowers Formation. Additionally, the enigmatic Cupittheca and some indeterminate hyoliths are figured to illustrate aspects of hyolith morphology. Guduguwan hardmani, widespread in Ordian-early Templetonian strata of northern Australia, is here recorded from the early Templetonian of the eastern Georgina Basin. A new family Gakidae is established for sulcavitide hyolithomorphs with a conch of pentagonally tabernacular transverse section, to include Gaka, Kalkatungu gen. nov. and possibly Dorsolinevitus. New genera are the hyolithid Yalarrnga mara gen. et sp. nov., sulcavitid Kulangarra kutjurru gen. et sp. nov., gakid Kalkatungu murlu gen. et sp. nov. and angusticornid Yuku tjurtu gen. et sp. nov.; new species are Loculitheca kunka sp. nov., Carinolithes tjikilirri sp. nov., ?Sololites kankari sp. nov., ?Shandongolithes thakal sp. nov., ?Gerkella thuka sp. nov. and ?Yacutolituus rakatju sp. nov. Taxa in open nomenclature are Foersteotheca cf. dubecensis, ?Holmitheca sp. and ?Dorsojugatus sp. On present knowledge, the potential for an Australian Cambrian hyolith biozonation is limited in the Early Cambrian, but for the Middle Cambrian, G. hardmani is a widespread Ordian-early Templetonian indicator, while hyolith distribution in the Monastery Creek Phosphorite Member suggests a faunal turnover at or about the incoming of Acidusus atavus which may provide a basis for biozonation in the Floran stage.     

Late Middle Cambrian trilobites from St Valentines Peak and Native Track Tier,northwestern Tasmania

Late Middle Cambrian trilobites are described from two localities in northwestern Tasmania. Twenty-four trilobite taxa are documented. The 15 agnostoid species include Paraclavagnostus longus sp. nov. which is placed in the Utagnostinae, a new subfamily of the Clavagnostidae. The nine polymeroid species include a new member of the Rhyssometopidae, Tasmana truncata gen. et sp. nov. Three other new species of polymeroids are erected: Fuchouia tasmaniensis, Nepea delicata and Nepea hellyeri. Both faunas correlate with the Lejopyge laevigata Zone on the northern Australia biostratigraphic scale, possibly with the L. laevigata II Zone. When compared with Hunan, China, correlation is with the upper part of the Lejopyge laevigata Zone, and particularly with the lower part of the Proagnostus bulbus Zone.     

Revision of two phragmodontid species (Conodonta) from the Darriwilian (Ordovician) of the Canning Basin in Western Australia and phylogeny of the Cyrtoniodontidae

Zhen, Y.Y. 9 July 2019. Revision of two phragmodontid species (Conodonta) from the Darriwilian (Ordovician) of the Canning Basin in Western Australia and phylogeny of the Cyrtoniodontidae. Alcheringa XX, xxx–xxx. ISSN 0311-5518

Based on re-examination of the material used in the original study from the subsurface Goldwyer and Nita Formations (middle Darriwilian, Middle Ordovician) of the Canning Basin, Western Australia, two phragmodontid species (Phragmodus polystrophos Watson and Ph. spicatus Watson) are revised as having a septimembrate apparatus including geniculate (Ph. polystrophos) or nongeniculate (Ph. spicatus) M, triform alate Sa, modified tertiopedate (Ph. polystrophos) or tripennate (Ph. spicatus) Sb, modified bipennate Sc, modified quadriramate Sd, carminate Pa and pastinate Pb elements. Characterized by a carminate Pa element in their respective species apparatuses, these two species demonstrate a close phylogenetic relationship with Phragmodus cognitus Stauffer from the Late Ordovician (Sandbian) of North America. These distinctive shared characters have allowed their accommodation within a new genus, Protophragmodus gen. nov., which represents an evolutionary lineage separated from species of Phragmodus Branson & Mehl (sensu stricto). In addition, it is postulated that the Cyrtoniodontidae might have originated in the early–middle Darriwilian from ‘Plectodina’ in shallow-water settings, with Phragmodus (sensu stricto), the most derived part of the family, perhaps directly evolving from Protophragmodus gen. nov. in the late Darriwilian and then becoming cosmopolitan, deeper-water dwellers in the Late Ordovician.

Y.Y. Zhen [yong-yi.zhen@planning.nsw.gov.au], Geological Survey of New South Wales, W.B. Clarke Geoscience Centre, 947–953 Londonderry Road, Londonderry, NSW 2753, Australia.     

Review of the Cambrian acrotretid brachiopod Neotreta

The Cambrian acrotretid brachiopod Neotreta Sobolev 1976 is reviewed and re-illustrated, based on new material of the type species, N. tumida Sobolev 1976, from the lower Upper Cambrian of Siberia; Neotreta orbiculata Koneva 1990, originally described from the Middle Cambrian of Kazakhstan, has been obtained from roughly coeval beds in Shropshire, England; Neotreta pusilla Koneva 1986 was unavailable for study. Two new species, N. davidi and N. karagailensis, are described from Queensland, Australia, and Kirgizia, Central Asia respectively.     

A phosphatic stromatolite (Ilicta cf. composita Sidorov) from the Middle Cambrian,northern Australia

Phosphatic stromatolites from the early Middle Cambrian (Ordian) of the Georgina Basin are described and identified as Ilicta cf. composita Sidorov. Based on Öpik's interpretation of the early Middle Cambrian, the age of the Georgina Basin specimens is similar to that of the type specimens described from the late Early Cambrian of Eastern Siberia. Phosphatic stromatolites occur at the base of dolomitized and partially silicified bioherms up to 4 m thick. The phosphatic forms overlie impermeable, cemented pavement surfaces which were covered by stratiform stromatolites from which rose columnar forms up to 5 cm in height. The stromatolites were phosphatized by penecontemporaneous diagenetic reactions that took place just below the sediment water interface and above the impermeable substrates.     

Middle Ordovician (Darriwilian) conodonts from the Goldwyer Formation of the Canning Basin,Western Australia

Zhen, Y.Y., Normore, L.S., Dent, L.M. & Percival, I.G., 11 July 2019. Middle Ordovician (Darriwilian) conodonts from the Goldwyer Formation of the Canning Basin, Western Australia. Alcheringa 44, 25–55. ISSN 0311-5518

Middle Ordovician conodonts attributed to 46 species were recovered from a stratigraphic interval spanning the Willara, Goldwyer and Nita formations in core sections from the Sally May-2 and Theia-1 petroleum exploration wells in the Canning Basin, Western Australia. The Histiodella serrata, Histiodella holodentata and Eoplacognathus pseudoplanus biozones are recognized in the lower and middle part of the Goldwyer Formation, indicative of an early–middle Darriwilian age. This revised conodont biostratigraphy enables more precise correlation with North America and North and South China. Several biogeographically distinctive conodont species, most likely of North Chinese origin, are recorded from the Goldwyer Formation. Their presence signals a strong palaeobiogeographic connection between the Sino-Korean Craton and the Canning Basin on the western margin of eastern Gondwana during the late Middle Ordovician.

Y.Y. Zhen* [yong-yi.zhen@planning.nsw.gov.au], W.B. Clarke Geoscience Centre, Geological Survey of New South Wales, 947–953 Londonderry Road, Londonderry NSW 2753, Australia; L.S. Normore [leon.normore@dmirs.wa.gov.au]; L.M. Dent [louisa.dent@dmirs.wa.gov.au], Department of Mines, Industry Regulation and Safety, Mineral House, Geological Survey of Western Australia, 100 Plain Street, East Perth, WA 6004, Australia; I.G. Percival [ian.percival@planning.nsw.gov.au], W.B. Clarke Geoscience Centre, Geological Survey of New South Wales, 947–953 Londonderry Road, Londonderry NSW 2753, Australia;     

First record of the trace fossil Protovirgularia from the Middle Permian of southeastern Gondwana (southern Sydney Basin,Australia)

LUO, M. &; SHI G.R., February 2017. First record of the trace fossil Protovirgularia from the Middle Permian of southeastern Gondwana (southern Sydney Basin, Australia). Alcheringa 0, 000–000. ISSN 0311-5518.

This study reports the first examples of well-preserved chevronate trails referable to Protovirgularia longespicata De Stefani, 1885 Stefani, DE.C., 1885. Studi paleozoologici sulle creta superiore e media dell' Apennino settentionale. Atti della Reale Accademia dea Lincei, Memorie 22, 101?134. [Google Scholar] from the early Middle Permian (Roadian) upper Wandrawandian Siltstone of the southern Sydney Basin, southeastern Australia. The highly meandering trace with closely spaced, papillate chevrons is interpreted to have been produced by the locomotion-feeding behaviour of certain protobranch bivalves in an offshore environment. The dense trails occurring on the upper bedding planes of pebbly siltstone may represent a gregarious lifestyle, where junior and senior individuals of the trace-maker bivalves coexisted while moving within sediments. The Wandrawandian Protovirgularia also represents the first known occurrence of this ichnotaxon from a glaciomarine environment in the Permian eastern Gondwana. The global record of Protovirgularia occurrences suggests that these trails had a wide environmental distribution since the Cambrian, and there is no obvious difference in the environmental distribution of Protovirgularia after the Permian?Triassic transition.

Mao Luo [m.luo@deakin.edu.au] and G.R. Shi [guang.shi@deakin.edu.au], Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood Campus, 221 Burwood Highway, VIC 3125, Australia.     

Palaeobiogeography of the Ordovician trilobite Prosopiscus,with a new species from western New South Wales

Prosopiscus is particularly important in Ordovician palaeobiogeography because of its wide geographic distribution in Gondwana and peri-Gondwanan regions. It appears to have been confined to low palaeolatitudes, representing a characteristic member of the warm water eastern Gondwanan shelf faunas. Trends in the distribution of the Ordovician genus can be observed due to its long stratigraphic range. Prosopiscus was restricted to, and may have originated in, Australia during the late Early Ordovician (Bendigonian-Chewtonian). By the Middle Ordovician (Darriwilian), Prosopiscus had dispersed to other parts of Gondwana and peri-Gondwana, including the North and South China blocks, Tarim, central Himalayas, and the Argentine Precordillera (South America). Possible explanations for the distribution of Prosopiscus are that: (1) there were no oceanic barriers preventing dispersal of trilobites between different regions of Gondwana, thus permitting uninhibited migration over vast distances; (2) Prosopiscus was not restricted to a specific biofacies; (3) a major eustatic transgression during the early Darriwilian may have facilitated the dispersal of Prosopiscus in allowing further development and expansion of marine environments; and (4) a prolonged planktonic larval stage may have permitted wide dispersal.

Prosopiscus lauriei sp. nov. is described from the late Early Ordovician (Bendigonian-Chewtonian) Tabita Formation at Mount Arrowsmith, northwestern New South Wales, Australia. The new species is closely related to P. praecox, from the Nora Formation, Georgina Basin, central Australia, and to P. magicus from northwest China.     

Early Silurian (Llandovery) trilobites from the Cotton Formation,near Forbes,New South Wales,Australia

A trilobite fauna from the upper part of the Cotton Formation (late Llandovery, Spirograptus turriculatus Zone) in central west New South Wales includes the new species Raphiophorus sandfordi, Odontopleura (Sinespinaspis) markhami and Aulacopleura pogsoni. Species of Odontopleura and Aulacopleura have not previously been documented in Australasia. The association of these genera is observed in offshore biofacies in the Llandovery/Wenlock on several palaeocontinents. Affinities of the species are with congeners from Bohemia and northwestern Canada (Odontopleura, Aulacopleura) and Tarim and South China (Aulacopleura, Raphiophorus).     

Middle Cambrian to Lower Ordovician faunas from the Chingiz Mountain Range,central Kazakhstan

Tolmacheva, T.JU., Degtyarev, K.E., Samuelsson, J. & Holmer, L.E., December, 2008. Middle Cambrian to Lower Ordovician faunas from the Chingiz Mountain Range, central Kazakhstan. Alcheringa 32, 443–463. ISSN 0311-5518.

The middle Cambrian to Lower Ordovician back-arc sedimentary succession studied in the Kol'denen River and in the Zerbkyzyl Mountains of the central Chingiz Mountain Range is composed predominantly of siltstones, sandstones and volcaniclastic rocks with rare beds of micritic carbonates, black shales and cherts. Fossil assemblages including conodonts, lingulate brachiopods, arthropods, sponges and probable Tasmanites cysts were recorded both from the carbonate and chert beds showing that richly diverse marine environments existed directly adjacent to the volcanic arcs. The Kol'denen River localities contain a diverse upper Cambrian paraconodont assemblage of the open-sea affinity. The representatives of Rossodus, Cordylodus, Drepanodus and Variabiloconus, having an almost pandemic distribution and characteristic of basinal facies, dominate the Lower Ordovician conodont fauna. The Cambrian–Ordovician boundary transition is characterized by chert production that was more likely caused by a local productivity increase than by general changes in palaeooceanographic and palaeogeographical conditions.     

Late Cambrian (Iverian,Jiangshanian) fossils from the Professor Range area,Western Tasmania

Abstract

Late Cambrian (Iverian, Jiangshanian) agnostoids and trilobites are described from two localities in the Professor Range area of western Tasmania. The fossils occur within a thick folded flysch succession of siltstone, mudstone, quartzwacke sandstone and siliceous conglomerate that forms the lower part of the Owen Group correlatives in this area. The flysch succession has a conformable and probable gradational contact with the underlying Mt Read Volcanics and is abruptly overlain by the siliceous pebble-cobble conglomerate correlated with the Middle Owen Conglomerate of the West Coast Range. The stratigraphically lower southern locality contains the agnostoids Pseudagnostus sp. and Agnostinae gen. et sp. indet. plus the polymerid trilobites Parabolina sp., Hedinaspis sp. cf. H. regalis and Eugonocare sp. The northern locality contains the agnostoids Rhaptagnostus sp. and Pseudagnostus sp. plus the polymerid trilobites Hedinaspis sp. cf. H. regalis, Ketyna? sp. 1, Ketyna? sp. 2, and Cermatops sp. It is possible that most specimens of the cosmopolitan genus Hedinaspis belong in the type species, H. regalis.

Christopher J. Bentley [bigfossil@bigpond.com], 30 Albert Street, Clare SA 5453; James B. Jago [jim.jago@unisa.edu.au], University of South Australia, School of Natural and Built Environment, Mawson Lakes, SA 5095; Keith D. Corbett [keith.corbett@bigpond.com], 35 Pillinger Drive, Fern Tree Tas 7054, Australia.     

Poljanka strigosa,a new species of Protopsyllidiidae (Hemiptera,Sternorrhyncha) from the Middle Jurassic of China

Yang, G., Yao, Y.Z. & Ren, D., iFirst. Poljanka strigosa, a new species of Protopsyllidiidae (Hemiptera, Sternorrhyncha) from the Middle Jurassic of China. Alcheringa, 1–6. ISSN 0311-5518.

A new fossil species, Poljanka strigosa sp. nov., of the extinct family Protopsyllidiidae is described from the Middle Jurassic Jiulongshan Formation of Daohugou Village, Inner Mongolia, China. The new species is characterized by wings bearing long, stiff setae that are evident as stained impressions in the fine sedimentary rock. Comparison between Protopsyllidiidae and extant psylloids suggests that Protopsyllidiidae is probably closely related to extant psylloids.     

Repairs to an injured early Middle Cambrian Trilobite,Elkedra area,Northern Territory

Wang, Y., Shih, C., Szwedo, J. &; Ren, D. iFirst article. New fossil palaeontinids (Hemiptera, Cicadomorpha, Palaeontinidae) from the Middle Jurassic of Daohugou, China. Alcheringa, 1–12. ISSN 0311-5518.

A new genus and species assigned to the extinct family Palaeontinidae, Synapocossus sciacchitanoae Wang, Shih &; Ren, is described from the Middle Jurassic of Daohugou in Inner Mongolia, China. This new genus is established based on well-preserved fossil specimens with body and complete forewings and hind wings. It differs from other described genera by the following characters: small body size, RP and M₁ coalescing for an interval on the forewings and M_3 + 4 without bifurcation on the hind wings. The RP coalescence with M₁ in Synapocossus Wang, Shih &; Ren previously reported only in Turgaiella Becker-Migdisova &; Wootton, seems to be associated with strengthening of the anterior wing margin. The intra-specific and individual variations of Synapocossus and numerous other insect fossils of northeastern China probably indicate long-lasting ecological stresses and a competitive environment in the Middle Jurassic to Early Cretaceous ecosystems.     

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.     

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.     

Terminal Cambrian and Early Ordovician (Tremadocian) conodonts from Eastern Alborz,north-central Iran

Hadi Jahangir, Mansoureh Ghobadi Pour, Alireza Ashuri & Arash Amini, December 2015. Terminal Cambrian and Early Ordovician (Tremadocian) conodonts from Eastern Alborz, north-central Iran. Alcheringa ##, ###-###. ISSN 0311-5518.

Uppermost Cambrian (Furongian) and Lower Ordovician (Tremadocian) deposits of eastern Alborz in northern Iran contain several successive low- to moderate-diversity conodont associations including 13 genera and 19 species of euconodonts, paraconodonts and protoconodonts, which define six biozones: 1, the Proconodontus muelleri; 2, Eoconodontus notchpeakensis; 3, Cordylodus andresi; 4, Cordylodus proavus; 5, Paltodus deltifer; and 6, Paroistodus proteus zones. With the exception of Cordylodus andresi, which is otherwise known from Baltoscandia and from the Oaxaquia terrane (Mexico), all index-taxa are geographically widespread, allowing long-range correlation within the Cold Domain or the North Atlantic Province, and in particular with Baltica. Invasion of euconodonts in the Alborz region, defined by the first occurrence of Proconodontus muelleri, coincides closely with a steady rise in sea level and termination of carbonate sedimentation, whereas the transition from the Proconodontus muelleri to Eoconodontus notchpeakensis zones occurs during a highstand interval unlike in Laurentian sequences. The interval corresponding to the Cordylodus andresi and Cordylodus proavus zones, and the transition from the Paltodus deltifer to Paroistodus proteus zones coincided with unstable sea levels and the formation of shoal complexes. The lower boundary of the Floian Stage can be provisionally placed slightly below the first documented occurrence of Acodus sp. cf. A. kechikaensis, somewhat below the second unit of andesitic lava flows in the Simeh-Kuh section.

Hadi Jahangir [jahangir.hadi@gmail.com] and Alireza Ashuri [ashouri2001@yahoo.com] Department of Geology, Faculty of Sciences, Ferdowsi University, Azadi Square, Mashhad 91775-1436, Iran; Mansoureh Ghobadi Pour* [mghobadipour@yahoo.co.uk; m.ghobadipour@gu.ac.ir] and Arash Amini [a.amini@gu.ac.ir], Department of Geology, Faculty of Sciences, Golestan University, Gorgan 49138-15739, Iran. *Also affiliated with Department of Geology, National Museum of Wales, Cathays Park, Cardiff CF10 3NP, UK.