Revision of the type species of Phoidagnostus Whitehouse, 1936 (Middle Cambrian,Agnostida)

The type species of Phoidagnostus, P. limbatus Whitehouse, 1936, is redescribed on the basis of further excavation of the holotype which has revealed an associated pygidium. This also demonstrates that the species Hypagnostus varicosus Öpik, 1961 is a junior subjective synonym of P. limbatus. Phoidagnostus is closely related to Toragnostus and Cotalagnostus.     

On the integration of Ordovician conodont and graptolite biostratigraphy: new examples from Gansu and Inner Mongolia in China

Wang, Z.H., Bergström, S.M., Zhen, Y.Y., Chen, X. & Zhang, Y.D., 2013. On the integration of Ordovician conodont and graptolite biostratigraphy: New examples from Gansu and Inner Mongolia in China. Alcheringa 37, 510–528. ISSN 0311-5518.

Few Ordovician successions in the world contain both biostratigraphically highly diagnostic conodonts and graptolites permitting an integration between standard biozones based on these fossil groups. The Sandbian Guanzhuang section in the vicinity of Pingliang in the Gansu Province has an outstanding graptolite record through most of the Nemagraptus gracilis and Climacograptus bicornis graptolite biozones. Calcareous interbeds in the succession yield biostratigraphically important conodonts, including some species used for biozonations in Baltoscandia and the North American Midcontinent. Likewise, the middle–upper Darriwilian Dashimen section in the Wuhai region of Inner Mongolia hosts both diverse graptolites of the Pterograptus elegans, Didymograptus murchisoni and lowermost Nemagraptus gracilis biozones, and conodonts of Midcontinent and Baltoscandic types. The distribution patterns of these index fossil groups provide an unusual opportunity to closely correlate conodont and graptolite biozones in the middle to upper Darriwilian to Sandbian interval. For instance, the base of the C. bicornis Biozone is approximately coeval with the base of the Baltoscandic B. gerdae Subbiozone and a level near the middle of the North American P. aculeata Biozone.

Zhi-hao Wang [zhwang@nigpas.ac.cn] Xu Chen [xu1936@gmail.com], and Yuan-dong Zhang [ydzhang@nigpas.ac.cn], Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; Stig M. Bergström [stig@geology.ohio-state.edu], School of Earth Sciences, Division of Earth History, The Ohio State University, Columbus, OH 43210, USA; Yong Yi Zhen [yongyi.zhen@austmus.gov.au], Australian Museum, 6 College Street, Sydney NSW 2010, Australia.     

Early Ordovician conodonts from Zhejiang Province,southeast China and their biostratigraphic and palaeobiogeographic implications

Forty-two conodont species are documented from the Liuxia, Shijiatou and Jingshan formations in Zhejiang Province of southeast China, located palaeogeographically on the Jiangnan Slope offshore to the Yangtze Platform. From these faunas, eight successive conodont biozones of Tremadocian to middle Floian (Early Ordovician) age are recognized, including the Cordylodus lindstromi Biozone, Cordylodus angulatus Biozone, Chosonodina herfurthi Biozone, Paltodus deltifer Biozone, Paroistodus proteus Biozone, Triangulodus bifidus Biozone, Serratognathus diversus Biozone and Prioniodus elegans Biozone. Several zonal index species of the Baltoscandian succession—Paltodus deltifer, Paroistodus proteus and Prioniodus elegans—are described and illustrated in detail for the first time from South China. Co-occurrence of P. proteus and Serratognathus bilobatus in several samples below the appearance of P. elegans also confirms correlation of the S. diversus Biozone (basal Floian) with the upper P. proteus Zone of the Baltoscandian succession. These Zhejiang faunas are dominated by pandemic forms, and are similar to those of the Open-Sea Realm elsewhere, inhabiting deep, offshore environments.     

A new assemblage of graptolites,rhabdopleuran hemichordates and chitinous hydroids from the late Arenig (Ordovician) of the Banestan area,east-central Iran

A rich benthic and planktonic graptolite fauna is associated with encrusting rhabdopleuran hemichordates and chitinous hydrozoans in the late Arenig (Ordovician) part of the Katkoyeh Formation at Banestan, east-central Iran.

New taxa described here are the dendroid graptolites Callograptus huckriedei sp. nov. and Dictyonema bitubulata sp. nov. Other dendroid graptolites Dendrograptus sp. cf. D. flexuosus J. Hall, 1865; Acanthograptus divergens Skevington, 1963; and Thallograptus ?succulentus Ruedemann, 1904 are described. The tuboid graptolite Galeograptus sp., the rhabdopleuran hemichordates Rhabdopleura sp. aff. R. primaevus (Kozlowski, 1967) and Kystodendron sp., and the chitinous hydroid Palaeotuba sp. are also described. Graptoloid graptolites described here are Aulograptus? sp., Didymograptus incertus Perner, 1895, Undulograptus formosus (Mu & Lee, 1958), and Yutagraptus sp. cf. Y. mantuanus Riva, 1994. All but two species-level taxa are described from Iran for the first time.

The fauna is confirmed as being late Arenig or, less likely, early Llanvirn and thus probably correlates with the early part of the Darriwilian stage. It resembles the Atlantic cold water faunas in lacking isograptids and sinograptids.     

Conodont fauna and biostratigraphy of the Honghuayuan Formation (Early Ordovician) of Guizhou,South China

Serratognathus diversus An, Cornuodus longibasis (Lindström), Drepanodus arcuatus Pander, and eleven other less common conodonts, including Cornuodus? sp., Oistodus lanceolatus, Protopanderodus gradatus, Protoprioniodus simplicissimus, Juanognathus variabilis, Nasusgnathus dolonus, Paltodus? sp., Scolopodus houlianzhaiensis, Semiacontiodus apterus, Semiacontiodus sp. cf. S. cornuformis and Serratognathoides? sp., are described and illustrated from the Honghuayuan Formation in Guizhou, South China, concluding revision of the conodont fauna from this unit, which comprises 24 species in total. The most distinctive species in the fauna, S. diversus, consists of a trimembrate apparatus, including symmetrical Sa, asymmetrical Sb and strongly asymmetrical Sc elements. This species concept is supported by the absence of any other element types in a large collection represented by nearly 500 specimens of this species. The fauna indicates a late Tremadocian to mid-Floian age (Early Ordovician) for the Honghuayuan Formation, which was widely distributed on the Yangtze Platform in shallow water environments. Previously published biostratigraphic zonations for the Honghuayuan Formation are reviewed, and revised on the basis of our knowledge of the entire conodont fauna, supporting the establishment of three biozones, Triangulodus bifidus, Serratognathus diversus, and Prioniodus honghuayanensis biozones in ascending order. Species of Serratognathus enable correlation between Ordovician successions of South China, North China (North China Platform and Ordos Basin), Tarim Basin, and further afield into Malaysia and northwestern Australia.     

Conodonts and tabulate corals from the Upper Ordovician Angullong Formation of central New South Wales,Australia

Zhen, Y.Y., Wang, G.X. &; Percival, I.G., August 2016. Conodonts and tabulate corals from the Upper Ordovician Angullong Formation of central New South Wales, Australia. Alcheringa 41, xxx–xxx. ISSN 0311-5518.

The Angullong Formation is the youngest Ordovician unit exposed in the Cliefden Caves area of central New South Wales. Its maximum age is constrained by a Styracograptus uncinatus graptolite Biozone fauna at the very top of the underlying Malongulli Formation, but the few fossils previously reported from higher in the Angullong Formation are either long-ranging or poorly known. From allochthonous limestone clasts in the middle part of the formation, we document a conodont fauna comprising Aphelognathus grandis, A. solidum, Aphelognathus sp., Aphelognathus? sp., Belodina confluens, Drepanoistodus suberectus, Panderodus gracilis, Panderodus sp., Phragmodus undatus, Pseudobelodina inclinata and Pseudobelodina? sp. aff. P. obtusa, which supports correlation with the Aphelognathus grandis Biozone (late Katian) of the North American Midcontinent succession. The species concepts of Aphelognathus and Pseudobelodina are reviewed in detail. Associated corals are exclusively tabulates, dominated by agetolitids, including Agetolites angullongensis sp. nov., Heliolites orientalis, Hemiagetolites breviseptatus, Hemiagetolites sp. cf. H. spinimarginatus, Navoites sp. cf. N. circumflexa, Plasmoporella bacilliforma, P. marginata, Quepora sp. cf. Q. calamus and Sarcinula sp. Affinities of the coral fauna from the Angullong Formation are closer to faunas from northern NSW and northern Queensland than to the locally recognized Fauna III of late Eastonian age in central NSW. We propose a subdivision of Fauna III to account for this difference, with the late Katian Fauna IIIB characterized by the incoming of agetolitid corals. The currently known distribution of representatives of this group with adequate age constraints suggests that agetolitids possibly originated in North China, subsequently migrating to Tarim, South China and adjacent peri-Gondwanan terranes while also spreading eastward to northern Gondwana, where they progressively moved through eastern Australia to reach the central NSW region by the early Bolindian.

Yong Yi Zhen* (yong-yi.zhen@industry.nsw.gov.au) and Ian G. Percival (ian.percival@industry.nsw.gov.au), Geological Survey of New South Wales, W.B. Clarke Geoscience Centre, 947–953 Londonderry Road, Londonderry, NSW 2753, Australia; Guangxu Wang (gxwang@nigpas.ac.cn), State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, 39 East Beijing Road Nanjing 210008 PR China.     

Miocene scleractinian corals from a mixed siliciclastic–carbonate system: Bakhtiari succession,Zagros Basin (central-western Iran)

Colonial scleractinian corals were sampled from three levels within a Miocene marine unit of the Bakhtiari succession, Zagros Basin, central-western Iran. The first two coral-bearing intervals, A and B, contain small-scale scattered colonies and show a poor coral diversity, whereas the third, consisting of a strongly lithified limestone package, reflects a well-developed biostromal framework with higher coral skeletal volume within the Bakhtiari succession. The Bakhtiari succession coral assemblages are characterized by Porites sp. cf. P. maigensis, Porites sp. cf. P. mancietensis, Porites sp. cf. P. collegniana, Tarbellastraea reussiana, Favia sp., Montastrea sp. cf. P. tchihatcheffi, Favites sp. cf. P. neugeboreni, Favites sp. cf. P. neuvillei, Agathiphyllia sp. and Acropora sp. Sedimentological and palaeontological data indicate that the depositional environment is consistent with a mixed carbonate–siliciclastic ramp that was gently deepening basinwards from the shoreline. The hemispherical and massive growth forms of colonies and sparse branching forms dominated the well-illuminated euphotic zone. Abundant domestone and dense pillarstone coral growth fabrics interdigitating with coarse-grained terrigenous sediments developed in the shallow inner ramp environment. Branching forms and meandroid branching colonies together with some massive forms mostly inhabited the low-energy conditions of the lower euphotic to oligophotic zones of the middle ramp. In the middle parts of the mixed carbonate–siliciclastic ramp, sparse pillarstone together with domestone comprises a mixstone coral growth fabric. Fluctuations in nutrient and clastic sediment input, salinity and the growth of red algae likely terminated coral growth.     

The Palaeoenvironmental Implications of the Distribution of Intertidal Foraminifera in a Tropical Australian Estuary: a Reconnaissance Study

Modern intertidal foraminifera were investigated in a mangrove‐lined microtidal distributary channel of the Barron River Delta (Cairns, Queensland, Australia). A monospecific assemblage of Trochammina inflata characterises saltmarsh environments (Biozone 1), whilst the more regularly inundated tidal flat is dominated (≥55%) by Ammonia beccarii (Biozone 2). Within the tidal flat environment, two foraminiferal subdivisions can be recognised; a high tidal flat assemblage (Biozone 2a) characterised by ≥70% Ammonia beccarii and low diversity, and a low tidal flat assemblage (Biozone 2b) with 55–65% Ammonia beccarii and high diversity (due to the settling out of small allochthonous species transported into the estuary from shelf environments). Foraminiferal distributions are also compared with tide levels estimated in the field. It appears approximately that Biozone 1 occurs between High Water and Mean High Water (MHW), Biozone 2a between MHW and Mean Tide Level (MTL), and Biozone 2b between MTL and Low Water. From this preliminary study, it is concluded that foraminifera possess significant potential in palaeoenvironmental studies of tropical Australian estuaries as indicators of intertidal environments, and also tidal levels.     

Didymograptellus kremastus n. sp., a new name for the Chewtonian (mid-Floian,Lower Ordovician) graptolite D. protobifidus sensu Benson & Keble, 1935, non Elles, 1933

Vandenberg, A.H.M., December 2017. Didymograptellus kremastus n. sp., a new name for the Chewtonian (mid-Floian, Lower Ordovician) graptolite D. protobifidus sensu, non. Alcheringa 42, 259–268. ISSN 0311-5518.

The ‘tuning-fork’ didymograptid previously referred to as Didymograpt(ell)us protobifidus is common in Victoria where it is confined to the Chewtonian (mid-Floian). Biometric differences indicate that the mid-Floian form is not conspecific with the holotype of the Darriwilian Didymograptus protobifidus Elles, 1933 and the Floian form is thus renamed Didymograptellus kremastus n. sp. Study of the Valhallfonna Formation faunas on Spitsbergen indicated that the Floian form of D. ‘protobifidus’ differs from Didymograptellus bifidus (Hall) in both its morphology and stratigraphic distribution but a later study of the Cow Head Group on Newfoundland concluded that they are one species. My study, of more than 50 specimens of Didymograptellus from the Floian of Victoria, Australia, shows that the two are different and that similar differences exist in the Cow Head Group populations of Didymograptellus. The Chewtonian (Ch1) Didymograptellus protobifidus Biozone is renamed D. kremastus Biozone.

Alfons H.M. Vandenberg, [lanceolatus@hotmail.vic.gov.au], [avandenberg@museum.vic.gov.au] Museums Victoria, GPO Box 666, Melbourne 3001, Victoria, Australia.     

Palynology of glacial sediments from the Guandacol Formation (Middle Carboniferous) in the Cerro Bola area,Paganzo Basin,Argentina

The palynoflora of surface samples of glacial deposits from the Guandacol Formation in the Cerro Bola area of the Argentinian Paganzo Basin is documented. The existence of glacial related diamictites in this area has been previously ignored. The fossiliferous levels are located in section B of the formation, which corresponds to the earlier stages of deglaciation. The assemblage contains abundant monosaccate pollen grains whose global incoming is not older than early Namurian (Middle Carboniferous). Many species of this palynoflora are present in equivalent stratigraphic sequences of Argentina and can be referred to Sub-biozone A of the Raistrickia densa-Convolutispora muriornata Biozone (Namurian-Stephanian). New species described here are Cyclogranisporites rinconadensis and Tricidarisporites gutii.     

An Early Permian brachiopod fauna of Gondwanan affinity from the Baoshan block,western Yunnan,China

The present paper describes and illustrates an Early Permian brachiopod fauna collected from two localities from the upper part of the type Dingjiazhai Formation near Youwang, 30 km south of Baoshan in the Baoshan block, western Yunnan, China. The brachiopod fauna is dominated by Stenoscisma sp. and Elivina yunnanensis sp. nov. and exhibits strong generic and some specific links with faunas from the Bisnain assemblage of Timor and the Callytharra Formation of Western Australia and, to a lesser extent, faunas from the Jilong Formation of southern Tibet, the Tashkazyk Formation of southeastern Pamir, the lower Toinlungkongba Formation of northwestern Tibet, the upper Pondo Group of central Tibet, and the Jimba Jimba Calcarenite of the Carnarvon Basin, Western Australia. Based on these correlations, a Late Sakmarian (Sterlitamakian) age is preferred for the Dingjiazhai brachiopod fauna. Two new species are proposed: Globiella youwangensis sp. nov. and Elivina yunnanensis sp. nov.     

Triassic plant fossils from Pollock Road,Southland, New Zealand

Pole. M. S., & Raine. J. I., 1994:03:28. Triassic plant fossils from Pollock Road, Southland. New Zealand. Alcheringa 18, 147–159. ISSN 0311-5518.

Sedimentary rocks of the Murihiku Supergroup considered to be latest Triassic (Rhaetian), crop out about 10 m below the Glenham Porphyry, near Glenham, New Zealand. They contain the vegetative macrofossils Marchantites sp. (Hepaticae), Pachydermophyllum praecordillerae (Frenguelli) Retallack and Pachydermophyllum benmorensis Anderson & Anderson (Peltaspermaceae), cf. Dicroidium dubium var. dubium Anderson & Anderson (Corystospermaceae), Desmiophyllum sp. cf. D. indicum Sahni (possible conifer), and Gingkophytopsis sp. (possible progymnosperm).

Reproductive material includes ovulate structures (Peltaspermum cournanei sp. nov.), pollenbearing structures (Antevsia sp.) and probably seeds of the Peltaspermaceae, ? Umkomasia (Corystospermaceae), and a possible progymnosperm microsporophyll.

The palynoflora is dominated by bisaccate gymnospermous pollen, mainly Alisporites spp., consistent with the presence of corystosperm macrofossils. Moderately common pollen of Cycadopites spp. may be of peltasperm origin.     

Australian Cenozoic Bryozoa, 2: Free-living Cheilostomata of the Eocene St. Vincent Basin,S.A., including Bonellina gen. nov

Schmidt, R., March 2007. Australian Cenozoic Bryozoa, 2: Free-living Cheilostomata of the Eocene St. Vincent Basin, S.A., including Bonellina gen. nov. Alcheringa 31, 67-84. ISSN 0311-5518.

Free-living bryozoans are diverse in the Eocene sediments of the St. Vincent Basin, South Australia. They include Bonellina pentagonalis gen. et sp. nov., Otionellina sp. cf. O. exigua (Tenison Woods), Otionellina sp. cf. O. cupola (Tenison Woods), Tubiporella magna (Tenison Woods), Celleporaria nummularia (Tenison Woods), and an indeterminate species only found as moulds. This diversity and abundance is highest in the sediments representing the initial transgressive marine facies, where they occur in ‘sand fauna’ bryozoan assemblages (e.g. with Melicerita and Siphonicytara). Free-living bryozoans decrease up-section and are absent from latest Eocene sediments, indicating a significant environmental shift.

Rolf Schmidt [rschmid@museum.vic.gov.au], Museum Victoria, Melbourne, Vic 3001, Australia; received 18.3.2005, revised 14.12.2005.     

Tertiary frogs from South Australia

Four species of hylid and leptodactylid frogs are reported from the Tertiary (mid-Miocene) Ngapakaldi fauna of the Etadunna Formation at Lake Palankarinna, South Australia. The species comprise Limnodynastes archeri sp. nov., Litoria sp. cf. caerulea (White), Litoria sp. indet. and Australobatrachus ilius Tyler. Previously the extant genera Limnodynastes and Litoria have been known only from Quaternary deposits.     

Thelodont fish and conodonts from the Early Devonian of Reefton,New Zealand

Thelodont scales and associated fragments of conodont elements identified as Turinia sp. cf. Turinia australiensis and Ozarkodina sp. cf. Ozarkodina buchanensis respectively are described for the first time from the Early Devonian Murray Creek Formation of Reefton, New Zealand. The conodont and thelodont components of the fauna suggest a late Pragian to early Emsian age for the assemblage.     

A rare,late Paleocene molluscan faunule from the Kings Park Formation,Perth Basin,Western Australia

A shallow marine faunule of eight taxa from the Kings Park Formation of the Perth Basin is the first described Paleocene molluscan assemblage from Western Australia. These species are part of a depauperate suite of macroinvertebrates (molluscs, echinoids and corals) derived from deep, onshore caissons in Perth and are inferred to be late Paleocene in age, based on planktonic foraminiferal biostratigraphy and associated age ranges of the molluscan fauna. Bivalves are Sarepta austranaxa sp. nov. (Sareptidae), Solemya kingsparki sp. nov. (Solemyidae), Periploma vivarirex sp. nov. (Periplomatidae), Parvamussium sp. nov.? (Propeamussiidae), Serripecten? sp. (Pectinidae) and Venericardia (Rotundicardia) petraea Darragh (Carditidae). Gastropods are Levifusus? sp. cf. L.? quadrifunifer Darragh (Buccinidae), and Columbarium rumatoides Darragh (Turbinellidae). Bivalves dominate the fauna in dark, glauconitic siltstone and sandstone facies; gastropods are of relatively poor preservation and low diversity.     

Early Devonian Pacificocoelia sinica (Brachiopoda) from Northeastern Inner Mongolia

Leptocoeliid brachiopods from the Early Devonian Baruntehua Formation of Dong Ujimqin Qi, northeastern Inner Mongolia were assigned to Leptocoelia by Su (1976) and Zhang(1983), and subsequently to Pacificocoelia by Hou & Boucot (1990). Transverse serial sections of Pacificocoelia sinica are illustrated hère, for the first time, based on topotype specimens. The known geographic range o Pacificocoelia is from northern China, North America, South America and Kazakhstan (Eastern Americas Realm and also occurs in east-central Asia). Atlanticocoelia is regarded hère as a junior synonym of Pacificocoelia.     

Trilobite faunas and palaeoenvironmental setting of the Silurian (early Ludlow) Melbourne Formation,central Victoria

Trilobites are common faunal elements in the Melbourne Formation, a unit of early Ludlow (upper nilssoni Biozone) age, which crops out extensively in the Darraweit Guim Province of the Melbourne Zone, central Victoria. New diagnoses are given for species previously described, including Maurotarion euryceps (McCoy, 1876; = Cyphaspis spryi Gregory, 1901), Raphiophorus jikaensis (Chapman, 1912; = Ampyx yarraensis Chapman, 1912), Cromus simpliciculus (Talent, 1964), Cromus spryi (Chapman, 1912), Sthenarocalymene kilmorensis (Gill, 1945; = Gravicalymene hetera Gill, 1945) and Trimerus harrisoni (McCoy, 1876). A new phacopid genus, Orygmatos is described, represented by the species O. yanyeani gen. et sp. nov. Other species newly described include Cromus melbournensis sp. nov., Arcticalymene australis sp. nov., “Ananaspis” woiwurrungi sp. nov. and Kettneraspis hollowayi sp. nov.

Species composition of the trilobite fauna varies spatially, and a number of distinct assemblages can be defined. Abundant trilobite moult configurations are conclusive for interpretation of the benthic fauna as autochthonous, inferring depth estimations based on benthic community distribution to be valid. A depth-related succession of communities is recognised and indicate the Melbourne Formation was deposited at relatively shallow depths on a broad, eastwardly deepening shelf, with deposition dominated by storm processes. The palaeoenvironment comprised a BA-1 community including the Arcticalymene australis trilobite assemblage, restricted to very shallow depths (～20 m) on the SW coastal margin of the shelf and preserved in proximal tempestite lithologies; and a BA-5 community group containing three distinct trilobite assemblages dominated by species of Cromus and a deeper water fauna, preserved in distal tempestite lithologies and ranging widely over the shelf at depths in the range of maximum storm wave base (～50 – 80 m).     

Early Carboniferous Siphonodella (Conodonta) faunas from eastern Australia

Early to Middle Tournaisian conodont faunas with Siphonodella from ten sections in eastern Australia, between Gloucester in New South Wales and Rockhampton in Queensland, may be referred to the following ‘standard’ zones; 1 sulcata, 2 upper duplicata, 3 sandbergi, 4 lower crenulata and 5 isosticha-upper crenulata, in ascending order. In eastern Australia the first occurrences of Gnathodus cuneiformis, G. delicatus, G. typicus and Protognathodus cordiformis, near the base of the lower crenulata zone, are significantly earlier than in Europe and North America. Consequently the base of the isosticha-upper crenulata zone in eastern Australia is defined by the first appearance of G. punctatus rather than that of G. delicatus. On the present evidence it is difficult to reconcile some brachiopod and conodont occurrences in the Early-Middle Tournaisian of eastern Australia.

Seventeen discrete conodont species are discussed, four of which are described informally: Dinodus sp. nov. A, Dinodus sp. nov. B, Pinacognathus sp. nov. A, and a species of Siphonodella transitional between S. cooperi and S. crenulata.     

Late Ordovician conodont biozonation of Australia—current status and regional biostratigraphic correlations

Zhen, Y.Y. & Percival, I.G. March 2017. Late Ordovician conodont biozonation of Australia—current status and regional biostratigraphic correlations. Alcheringa 41, xxx–xxx. ISSN 0311-5518.

Seven conodont biozones are recognized in the Upper Ordovician of Australia. The Pygodus anserinus, Belodina compressa and Phragmodus undatus–Tasmanognathus careyi biozones are successively represented in the Sandbian. Although the Erismodus quadridactylus Biozone of the late Sandbian North America Midcontinent succession was previously recognized in the Stokes Siltstone of the Amadeus Basin and the Mithaka Formation of the Georgina Basin in central-north Australia, we argue for a middle–late Darriwilian age for these two units. Four conodont biozones, from oldest to youngest the Taoqupognathus philipi, T. blandus, T. tumidus–Protopanderodus insculptus and Aphelognathus grandis biozones, are established in the Katian of eastern Australia. Taoqupognathus species are particularly useful in correlation of the lower–middle Katian successions of eastern Australia with contemporary rocks in other parts of eastern Gondwana and peri-Gondwana, such as with the three major terranes of North and South China and Tarim. These regions, together with Sibumasu and eastern Australia, were part of the Australasian Superprovince during the Late Ordovician, with a strong palaeobiogeographic identity signalled by domination of Taoqupognathus, Tasmanognathus and Yaoxianognathus. Longstanding difficulties for precise correlation with the well-established North American Midcontinent or Baltoscandian successions in the Late Ordovician, owing mainly to strong endemism of the Australian faunas particularly from shallow-water settings, have been resolved by integration of regional conodont biostratigraphic schemes. The conodont biozonation of the Australian Upper Ordovician reviewed herein also provides a crucial chronological reference for better constraining the temporal and spatial range of Late Ordovician tectonostratigraphic events across the intracratonic basins of northern and western Australia and orogenic belts of eastern Australia.

Yong Yi Zhen* [yong-yi.zhen@industry.nsw.gov.au] and Ian G. Percival [ian.percival@industry.nsw.gov.au], Geological Survey of New South Wales, W.B. Clarke Geoscience Centre, 947–953 Londonderry Road, Londonderry NSW 2753, Australia.