Revised conodont and fusuline biostratigraphy of the Bamchi Formation (Pyongan Supergroup) at the Bamchi section,Yeongwol and the Carboniferous–Permian boundary in South Korea

Wang, Q., Wang, Y., Qi, Y., Wang, X., Choh, S.J., Lee, D.C. & Lee, D.J., November 2017. Yeongwol and the Carboniferous–Permian boundary in South Korea. Alcheringa 42, 245–258. ISSN 0311-5518

Six conodont and one fusuline zones are recognized on basis of a total of 25 conodont and 13 fusuline species (including seven unidentified species or species given with cf. or aff. in total) from the Bamchi Formation, Yeongwol, Korea. The conodont zones include the Streptognathodus bellus, S. isolatus, S. cristellaris, S. sigmoidalis, S. fusus and S. barskovi zones in ascending order, which can be correlated with the conodont zones spanning the uppermost Gzhelian to Asselian Age of the Permian globally. The fusuline zone is named the Rugosofusulina complicata–Pseudoschwagerina paraborealis zone. The co-occurrence of the conodont Streptognathodus isolatus (the Global Boundary Stratotype Section and Point index for the base of Permian) and Pseudoschwagerina (a Permian inflated fusuline) indicates that the Carboniferous–Permian boundary can be placed in the lower part of the Bamchi Formation in South Korea.

Qiulai Wang* [qlwang@nigpas.ac.cn] CAS Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Yue Wang* [yuewang@nigpas.ac.cn] LPS, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Yuping Qi* [ypqi@nigpas.ac.cn] Xiangdong Wang* [xdwang@nigpas.ac.cn] CAS Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Suk-Joo Choh [sjchoh@korea.ac.kr] Department of Earth and Environmental Sciences, Korea University, Seoul 02841, Republic of Korea; Dong-Chan Lee [dclee@chungbuk.ac.kr] Department of Earth Sciences Education, Chungbuk National University, Cheongju 28644, Republic of Korea; Dong-Jin Lee [djlee@andong.ac.kr] Department of Earth and Environmental Sciences, Andong National University, Andong 36729, Republic of Korea. *Also affiliated with: University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, PR China.     

Morphological analysis of Ozarkodina prolata Mawson and Ozarkodina midundenta (Wang & Ziegler) (Emsian conodonts) from South China

Lu, J.-F., November 2015. Morphological analysis of Ozarkodina prolata Mawson and Ozarkodina midundenta (Wang & Ziegler) (Emsian conodonts) from South China. Alcheringa 40, xxx–xxx. ISSN 0311-5518.

Investigations of conodonts from Emsian (Lower Devonian) strata at Bahe, Liujing and Daliantang in Guangxi and Yunnan, South China, provide new data on the morphological variability and phylogenetic affinity of Ozarkodina midundenta, a species initially assigned to Pandorinellina but transferred to Ozarkodina herein. Morphological analysis suggests that O. midundenta probably developed from O. prolata by progressive fusion of denticles in the middle third of the blade above the basal cavity in the Pa element.

Jian-feng Lu [lujfivan@sina.cn], Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, PR China. Also affiliated with University of Chinese Academy of Sciences, Beijing 100049, PR China.     

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.     

Early Carboniferous age for Arynshand Formation,Mongolian South Gobi,based on conodonts

Conodonts from the lowermost part of the Arynshand Formation at the Bayan-Khoshuu Ruins section in the Mushgai area, south Gobi, including Siphonodella cooperi, S. cf. crenulata and S. cf. isosticha, clearly indicate that the Arynshand Formation is Early Carboniferous rather than Devonian-Carboniferous. The formation rests unconformably on the volcanogenic Minjin Member of the Botuulkhudag Formation from which we have not recovered conodonts. The Arynshand Formation contains some presumably reworked Devonian conodonts which cannot be used to provide a reliable age.     

Middle Ordovician (early Dapingian) conodonts in the Central Andean Basin of NW Argentina

Carlorosi, J., Heredia, S. & Aceñolaza, G, 2013. Middle Ordovician (early Dapingian) conodonts in the Central Andean Basin of NW Argentina. Alcheringa 37, 1–13. ISSN 0311-5518.

This paper describes and analyzes the significance of a conodont fauna from the Alto del Cóndor Formation, exposed in the Los Colorados region of the Argentine Eastern Cordillera. Identified taxa are Baltoniodus triangularis, Baltoniodus sp. cf. B. triangularis, Drepanodus sp., Drepanoistodus basiovalis, Drepanoistodus sp. B., Erraticodon patu, Gothodus costulatus, Oistodus sp., Trapezognathus diprion, T. quadrangulum, Triangulodus sp. and Triangulodus? sp. The presence of Baltoniodus triangularis indicates the base of the Dapingian stage (Middle Ordovician). In addition, we report the coexistence of T. diprion and T. quadrangulum. The conodont association suggests a faunal affinity with Baltica and South China, both belonging to the Shallow-Sea Realm of the Temperate-Cold Domain.

Josefina Carlorosi [josefinacarlorosi77@gmail]com], INSUGEO—Universidad Nacional de Tucumán—CONICET, Miguel Lillo 205, (4000) Tucumán, Argentina; Guillermo F. Aceñolaza [acecha@webmail.unt.edu.ar], Universidad Nacional de Tucumán—CONICET, Miguel Lillo 205, (4000) Tucumán, Argentina; Susana Heredia [sheredia@unsj.edu.ar], CONICET–CIGEOBIO and Instituto de Investigaciones Mineras, Facultad de Ingeniería, Universidad Nacional de San Juan, Urquiza y Libertador, (5400) San Juan, Argentina. Received 22.8.2012; revised 18.10.2012; accepted 24.10.12.     

First records of Wuchiapingian (Late Permian) conodonts in the Xainza area,Lhasa Block,Tibet, and their palaeobiogeographic implications

Yuan, D.X., Zhang, Y.C., Zhang, Y.J., Zhu, T.X. & Shen, S.Z., 2014. First records of Wuchiapingian (Late Permian) conodonts in the Xainza area, Lhasa Block, Tibet, and their palaeobiogeographic implications. Alcheringa 38, 546–556. ISSN 0311-5518.

Conodonts are among the best fossil groups to provide high-resolution biostratigraphic correlation and resolve the palaeobiogeographic evolution of the Permian. However, they have been rarely reported from the Lhasa Block in Tibet. Here we report the first discovery of Wuchiapingian (early Lopingian) conodonts from the Xiala Formation in the Lhasa Block, Tibet. This conodont fauna includes two genera and three species (Clarkina liangshanensis, C. orientalis, Iranognathus sp.). The conodont fauna indicates that the Xiala Formation previously assigned to the Guadalupian actually ranges from late Kungurian to late Wuchiapingian. The existence of the late Wuchiapingian conodont species Clarkina orientalis and C. liangshanensis in the Lhasa Block provides additional data to support the viewpoint that this block probably had been in a warm-water regime during the Wuchiapingian (Lopingian).

Dong-Xun Yuan [yuanzi55@163.com], School of Earth Sciences and Engineering, Nanjing University, 22 Hankou Road, Nanjing, 210093, PR China and State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing, 210008, PR China; Yi-Chun Zhang [yczhang@nigpas.ac.cn] and Shu-Zhong Shen [szshen@nigpas.ac.cn] (corresponding author), State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing, 210008, PR China; Yu-Jie Zhang [zebiac@163.com] and Tong-Xing Zhu [ztongxing88@yahoo.com.cn], Chengdu Center, China Geological Survey, 2 Renming Road North, Chengdu, 610081, PR China. Received 9.1.2014; revised 1.4.2014; accepted 28.4.2014.     

Late Silurian and Early Devonian biostratigraphy in the Hill End Trough and the Limekilns area,New South Wales

Precordilleran Late Palaeozoic brachiopod genera considered for this palaeobiogeographical analysis belong to four faunal associations: the low diversity Early Carboniferous (Tournaisian) Protocanites scalabrinii-Azurduya chavelensis Zone; the Late Carboniferous (Bashkirian-Moscovian) Levipustula fauna, which appears in sequences associated with glacial intervals; the latest Carboniferous-earliest Permian (Gzhelian-Asselian) Rhipidomella-Micraphelia and Tuberculatella-Aseptella associations, and the Early Permian (mid to late Asselian) Tivertonia jachalensis-Streptorhynchus inaequiornatus Biozone. The brachiopod affinities of the Precordillera are compared with the biogeographical Late Palaeozoic regions previously suggested by other authors using cluster analysis. During the Bashkirian-Moscovian, the Precordilleran faunas show a high affinity with the Austral Realm because of the presence of the Levipustula faunal elements in Eastern Australia. At the same time the affinity with the central and North American Regions is very low. The Early Permian Precordilleran faunas demonstrate highest affinity with the Gondwanan Realm with several genera also linked to the Tethyan and Boreal Realms. After the Late Carboniferous glacial episodes that affected the southwestern Gondwanan margin, the Precordilleran region underwent climatic amelioration. Subsequently, the Early Permian Precordilleran brachiopod assemblages are characterized by typical cool to cold water genera widely developed in the core Gondwanan Realm, with fewer genera (such as Kochiproductus, Rhynchopora and Neochonetes) suggesting a warmer water influence. The Precordilleran faunas demonstrate an increase in brachiopod diversity from the Carboniferous to the Permian, related to water temperature changes and to the palaeogeographical evolution of the southwestern Gondwanan margin and the movement of Gondwana across the South Pole.     

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.     

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.     

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.