Spore assemblages from the Lower Devonian Xujiachong Formation from Qujing,Yunnan, China

Abstract: The Lower Devonian Xujiachong Formation from the vicinity of Qujing City, Yunnan, China is interpreted as a terrestrial‐fluviatile‐lacustrine sequence. It contains important nonmarine biotas including plants, fish and invertebrates. The plants are particularly interesting as they include many endemic taxa. Dispersed spore assemblages have been recovered from the upper part of this formation. The spores are well preserved and of moderate thermal maturity. They are systematically described and four new species erected: Aneurospora xujiachongensis sp. nov., Chelinospora ouyangii sp. nov., Camptozonotriletes? luii sp. nov. and Leiozonospora xichongensis sp. nov. One new combination is proposed: Aneurospora conica (Ouyang and Lu) comb. nov. This is a rare report of a Lower Devonian dispersed spore assemblage from the South China Plate. Indeed, few dispersed spore assemblages of this age are known outside of Euramerica and Northern Gondwana. It is suggested that the Xujiachong Formation spore assemblages can all be equated to the polygonalis‐emsiensis Spore Assemblages Biozone (PE SAB) of Richardson and McGregor (1986) indicating an early (but not earliest) Pragian to ?earliest Emsian age. However, caution is urged, because biostratigraphical interpretation is difficult owing to distinct differences between dispersed spore assemblages from South China and Euramerica/Northern Gondwana. This almost certainly reflects palaeophytogeographical variation and regional endemism among early land plant floras on widely separated land masses. Palynofacies analysis supports a nonmarine origin for the deposits of the Xujiachong Formation, with the very rare marine palynomorphs that were encountered interpreted as reworked.     

澳大利亚泥盆纪皱纹珊瑚生物地层及生物地理研究展望

通过对澳大利亚泥盆纪皱纹珊瑚属级分布的分析,认为泥盆纪珊瑚在该区经历了两大繁盛期,尤以Ｌｏｃｈｋｏｖｉａｎ－Ｅｍｓｉａｎ最盛,有大量新属产生,内板珊瑚和菲力甫珊瑚科分子要Ｐｒａｇｉａｎ期开始出现,绳珊瑚科的分子也在Ｅｍｓｉａｎ大量出现,这些分子继而通过洋流逐渐扩散到华南及老世界域其他省区。     

On the origin of bactritoids (Cephalopoda)

There is a high probability that bactritoids represent a paraphylum or polyphylum. The initial chambers or protoconchs of the Early-Middle DevonianBactrites Sandberger,Devonobactrites Shimansky, andLobobactrites Schindewolf are elongated spheres with a diameter of 0.3–1.0 mm. The initial chambers are larger in diameter than the slender, smooth shaft located adorally to the initial chamber. Similar apices occur in a number of Late Silurian sphaerorthoceridans with central siphuncles. Sphaerorthoceridans with a bactritoid-like apex and an eccentric siphuncle are known from the Early Devonian. The earliest questionableBactrites occurs in the Pragian (middle Early Devonian). By Emsian time bactritoids are common elements of cephalopod faunas.Bactrites-like orthocones of the Middle Ordovician and Late Silurian are homeomorphs with clearly different early growth stages. Thus, the time interval between the first appearance ofBactrites and the origin of ammonoids can be narrowed down to the Pragian to Early Emsian. The placement of the siphuncle in a ventral marginal position has been used as one of the critical morphologic features in defining the bactritoids. However, the displacement of the siphuncle from subcentral or eccentric positions toward the conch margin occurred at least three times during the Ordovician — Early Devonian evolution of the Orthocerida. Thus, there is a high probability that a marginal shift of the orthocerid siphuncle occurred in post-Emsian times, too.     

New species and biostratigraphic significance of middle Palaeozoic brachiopod genus Linguopugnoides Havliček

Linguopugnoides Havli?ek 1960, originally based on 3 Early Devonian (Lochkovian‐Pragian) species from the Czech Republic, is now construed as embracing at least 25 species distributed over all northern hemisphere continents as well as Australia, and extending from late Llandovery to early Emsian. Species‐diversity peaked during the Lochkovian when the genus was widespread, with 15 species having been reported. Four species are described as new. L. praecarens sp.nov. from the latest Silurian (Pridoli) of the Turkestan Range (South Tien Shan) is considered to be ancestral to the numerous, mainly late Lochkovian‐Pragian forms that appeared during the great diversification of the genus during the early Devonian. Three new species are described from the Lochkovian of the Zeravshan Range, Uzbekistan: L. rectiplicatus, L. diversiplicatus as well as the previously figured but not described L. kimi Rzhonsnitskaya. Species of Linguopugnoides have biostratigraphic and biogeographic significance and have obvious value for inter‐regional correlation.     

Thelodont Scales from the Lower Devonian Red Bay Group, Spitsbergen

Scales of nine thelodont taxa are described from the Red Bay Group of Spitsbergen, also characterized by its assemblage of other typical Early Devonian vertebrates. The four thelodont–bearing horizons of the lower Fraenkelryggen Formation yield typical Lochkovian thelodont assemblages, containing Boreania minima , Canonia grossi , Nikolivia depressa sp. nov., Nikolivia elongata , Nikolivia gutta and Turinia pagei . One horizon from the younger Ben Nevis Formation has a similar thelodont assemblage, except for two new taxa; Apalolepis angelica sp. nov. and Turinia barentsia sp. nov. The appearance of Turinia polita and the disappearance of Boreania minima is also characteristic for this assemblage. Comparison with similar faunas from the Northern Hemisphere supports this faunal change and allows further elaboration of Early Devonian thelodont biostratigraphy.     

Evolution of Devonian biodiversity of radiolarians with two porous spheres and one main spine

Features and major distinctions in the appearance and distribution of radiolarians with two porous spheres and one main spine in the Devonian basins are considered. Four solitary population waves and expansion scenario of radiolarians of this morphotype have been recognized in the Devonian. A new species, Radiobisphaera rozanovi sp. nov., from the Upper Emsian, Upper Eifelian, and Middle Frasnian of the southern Ural Mountains, from the Upper Eifelian of the Prague Basin (Barrandian), from the Middle-Upper Frasnian of the Rudnyi Altai, and from the Lower Famennian of the Timan-Pechora Basin and the Polar Ural Mountains is described.     

Devonian conodont biogeography: Quantitative analysis of provinciality

Cluster analysis of conodont faunas from each of 17 Lower‐lower Upper Devonian zones and subzones (data as reported by Klapper and Johnson, 1980) reveal changing patterns of provinciality.

Provinciality, expressed by a differentiation into western Laurussian and proto‐Tethyan biogeographic regions, is moderate in the lower Lochkovian but is low or absent in the upper Lochkovian‐lower Pragian. Provincialism returns in the Pragian and reaches its maximum development during the Emsian. Most Australian faunas are distinct from those of western Laurussia and the proto‐Tethys. Conodont faunas from suspect terranes of western North America display no unusual biogeographic affinities. Provincialism declines during the Eifelian and is only weakly developed in Givetian‐lower Frasnian faunas.

Changing global sea level during the Devonian may explain the development of Devonian conodont provinciality. As proposed by Klapper and Johnson (1980), low provinciality is associated with low stands of sea level. Endemic faunas develop in isolated epeiric seas during intermediate stages of sea level rise. High stands of sea level ultimately drown barriers to faunal exchange and prompt a return to low provinciality conditions.     

Teruelia diezii gen. et sp. nov.: an early polysporangiophyte from the Lower Devonian of the Iberian Peninsula

A new basal land plant, Teruelia diezii gen. et sp. nov., is described from the shallow‐water marine deposits of the Lower Devonian (Lochkovian–Pragian) Nogueras Formation of the Iberian Peninsula (north Gondwana palaeocontinent). Teruelia is preserved as a compression fossil and consists of isotomously branched, robust stems terminated in large, fusiform, twisted sporangia. This morphology suggests that Teruelia is very probably equivalent to Aglaophyton, a permineralized early polysporangiophyte known up to now only from the Lower Devonian (early Pragian to ?earliest Emsian) Rhynie Chert in Scotland (Laurussia palaeocontinent), which represents an early terrestrial hot‐spring ecosystem. Accepted phylogenies identify Aglaophyton as sister to vascular plants. Our phylogeny‐based results identify the Aglaophyton/Teruelia biological entity (i.e. Aglaophyton anatomical characters plus Teruelia external morphology) as the most direct vascular plant precursor. It shows that at least one Rhynie Chert type plant had a much wider distribution than previously known and suggests that Aglaophyton was not restricted to hydrothermal environments, unlike other Rhynie Chert plants.     

Early to Middle Devonian miospores from northern Saudi Arabia

Well-preserved palynomorph assemblages are recovered from the Devonian Jauf and Jubah formations in five shallow boreholes in the northern part of Saudi Arabia. These fully cored boreholes overlap stratigraphically to form a 1640 ft composite sequence. Miospores dominate the palynological assemblages of most samples. The assemblages are mainly composed of trilete spores but also contain cryptospores and monolete spores. One new genus, sixteen new species and two new varieties of miospores are described from the studied assemblages: Artemopyrainconspicua nov. sp., Artemopyrarecticosta nov. sp., Camarozonotriletesfilatoffii nov. sp., Camarozonotriletesrugulosus nov. sp., Cymbohilatesbaqaensis nov. sp., Cymbohilatescomptulus nov. sp., Cymbohilatesheteroverrucosus nov. sp., Cymbosporitesasymmetricus nov. sp., Dibolisporitespilatus nov. sp., Dictyotriletesbiornatus nov. sp., Gneudnasporadivellomedia (Chibrikova) Balme, 1988 var. divellomedia, Gneudnasporadivellomedia (Chibrikova) Balme, 1988 var. minor nov. var., Latosporitesovalis nov. sp., Scylasporacostulosa nov. sp., Squamisporaarabica nov. gen. and sp., Stellatisporamulticostata nov. sp., Zonotriletesarmillatus nov. sp. and Zonotriletessimplicissimus nov. sp. Their stratigraphic distribution is compared to the well-established Devonian West European zonation of Streel et al. (1987) (Streel, M., Higgs, K.T., Loboziak, S., Riegel, W., Steemans, P., 1987. Spore stratigraphy and correlation with faunas and floras in the type marine Devonian of the Ardenne-Rhenish region. Review of Palaeobotany and Palynology 50, 211-219). A late Pragian-Givetian age is suggested for this sequence. No characteristic Eifelian taxa are recorded, but this could be explained by a gap in palyniferous samples.     

Early Ordovician bivalves from Dali, West Yunnan, China

A bivalve fauna of Early Ordovician (late Arenig) age is described from the Hsiangyang Formation of the eastern part of West Yunnan, China. The fauna contains elements in common with Early Ordovician faunas of southern Gondwanan areas such as the Montagne Noire and Morocco and with those of Avalonia, together with several previously undescribed taxa. The following taxa are new: Biseriodonta simplex gen. et sp. nov.; Glyptarca sinensis sp. nov.; Trigonoglyptarca magna gen. et sp. nov.; Erhaiconcha xiangyangensis gen. et sp. nov.; Fasciculodonta impressa gen. et sp. nov.; Yunnanoredonia laevis gen. et sp. nov.; Daliella gen. nov.; Goniophorina ( Goniophorina ) contracta sp. nov.; Haidongoconcha radialis gen. et sp. nov.; Eopterinea aequiconcha gen. et sp. nov. The bivalve fauna includes the most diverse glyptarcid fauna and the earliest nuculanid and paracyclid known hitherto.   Eastern West Yunnan belonged to the Indochina terrane and it is concluded that the bivalve fauna represents a high-latitude assemblage and that the Indochina terrane should be considered a component part of the Peri-Gondwanan continent in the Ordovician; its bivalve faunas contrast with those of neighbouring terranes which have affinities with those of lower latitudes.     

Tabulate Corals after the Frasnian/Famennian Crisis: A Unique Fauna from the Holy Cross Mountains,Poland

Famennian tabulate corals were very rare worldwide, and their biodiversity was relatively low. Here we report a unique tabulate fauna from the mid- and late Famennian of the western part of the Holy Cross Mountains (Kowala and Ostrówka), Poland. We describe eight species (four of them new, namely ?Michelinia vinni sp. nov., Thamnoptychia mistiaeni sp. nov., Syringopora kowalensis sp. nov. and Syringopora hilarowiczi sp. nov.); the whole fauna consists of ten species (two others described in previous papers). These corals form two assemblages—the lower, mid-Famennian with Thamnoptychia and the upper, late Famennian with representatives of genera ?Michelinia, Favosites, Syringopora and ?Yavorskia. The Famennian tabulates from Kowala represent the richest Famennian assemblage appearing after the F/F crisis (these faunas appear some 10 Ma after the extinction event). Corals described here most probably inhabited deeper water settings, near the limit between euphotic and disphotic zones or slightly above. At generic level, these faunas show similarities to other Devonian and Carboniferous faunas, which might suggest their ancestry to at least several Carboniferous lineages. Tabulate faunas described here represent new recruits (the basin of the Holy Cross mountains was not a refuge during the F/F crisis) and have no direct evolutionary linkage to Frasnian faunas from Kowala. The colonization of the seafloor took place in two separate steps: first was monospecific assemblage of Thamnoptychia, and later came the diversified Favosites-Syringopora-Michelinia fauna.     

Patterns of evolution and extinction in proetid trilobites during the late Devonian mass extinction event,Canning Basin,Western Australia

Abstract: In the early Late Devonian, terminal Frasnian proetid trilobites have previously only been known from Europe and North Africa. For the first time, a rich fauna of late Frasnian proetids is described from the Virgin Hills Formation, Canning Basin, Western Australia. Seventeen species in six genera are described, of which three are new: Rudybole gen. nov., Palpebralina gen. nov. and Canningbole gen. nov. A new subgenus, Chlupaciparia (Australoparia) subgen. nov. is also described. Fourteen of the species are new: Palpebralia initialis sp. nov., P. pustulata sp. nov., ?P. sp. nov. A, Rudybole depressa sp. nov., Palpebralina pseudopalpebralis sp. nov. (comprising the subspecies P. pseudopalpebralis pseudopalpebralis subsp. nov. and P. pseudopalpebralis ultima subsp. nov.), P. minor sp. nov., P. ocellifer sp. nov., Canningbole latimargo sp. nov., C. henwoodorum sp. nov., C. macromma sp. nov., Pteroparia extrema sp. nov., Chlupaciparia (Chlupaciparia) planiops sp. nov., Chlupaciparia (Australoparia) australis sp. nov. and C. (Australoparia) lata sp. nov. The subspecies Rudybole adorfensis angusta subsp. nov. is also described. The proetids range through conodont Zones 11–13b and terminate at the Upper Kellwasser Event, which marks the terminal Frasnian mass extinction event. Three of the six proetid lineages, Palpebralia, Canningbole and Pteroparia, show evolutionary trends of eye reduction. Two of the remaining lineages, Rudybole and Palpebralina, consist exclusively of blind taxa. The last, Chlupaciparia, also comprises forms with reduced eyes. The proetids show a stepped pattern of extinction during the late Frasnian, which correlate with two Kellwasser biocrises documented in European/North African Frasnian sections. The highest diversity preceded the Lower Kellwasser event that occurred at the end of conodont Zone 12 and saw the extinction of all species present in that zone. However, only one genus, Pteroparia, locally became extinct. A major higher‐level taxonomic mass extinction at the top of Zone 13b initiated the Upper Kellwasser extinction event. This included extinction at the generic level, with all five remaining genera becoming extinct, and at the family level, with the loss of the Tropidocoryphidae.     

A NEW EARLY DEVONIAN THELODONT FROM CELTIBERIA (SPAIN), WITH A REVISION OF SPANISH THELODONTS

Abstract:  A revision of thelodont scales from the Lower Devonian of the Iberian Chains enables their grouping into two taxa: Turinia pagei and T. nachoi sp. nov. These taxa are clearly distinguishable by morphological and histological features; they also have a different stratigraphic range ( T. pagei is restricted to Lochkovian strata, whereas T. nachoi sp. nov. occurs within lower–middle Pragian rocks). The new species is represented by head, transitional (cephalopectoral) and trunk scales.     

Albaillellaria from the New England orogen, Eastern NSW, Australia

Radiolarian data provide important age constraints on the development of terranes within the New England orogen and have implications for existing tectonic models. Most radiolarian assemblages recovered from the orogen are of Late Devonian to Early Carboniferous ages. Albaillellaria comprise a minor proportion of the faunas present but have major biostratigraphic significance.Holoeciscus Foreman,Helenifore Nazarov and Ormiston,Circulaforma Cheng,Ceratoikiscum Deflandre,Protoalbaillella Cheng, andAlbaillella Deflandre, two new genera and three new species are found at various stratigraphic levels. Eleven radiolarian assemblages are recognised. In stratigraphic order these are theHelenifore laticlavium-Ceratoikiscum planistellare, Protoholoeciscus hindea, Holoeciscus formanae, Paraholoeciscus bingaraensis,Ceratoikiscum umbraculum, Protoalbaillella anaiwanensis, Albaillella paradoxa, Albaillella undulata-Albaillella indensis,Albaillella indensis-Albaillella furcata, Albaillella cartalla-Albaillella thomasi andCirculaforma omicron assemblages. There is an apparent biostratigraphic succession amongst the Albaillellaria in the New England orogen in whichProtoholoeciscus hindea n. gen. n. sp. is transitional betweenCeratoikiscum Deflandre andHoloeciscus Foreman andParaholoeciscus bingaraensis n. gen. n. sp. is transitional betweenHoloeciscus Foreman and theAlbaillella paradoxa Deflandre group.     

Early Devonian (Lochkovian) trilobites and brachiopods from the west Balkhash Region,Kazakhstan and their significance for regional terrane dynamics

A moderately diverse Early Devonian (Lochkovian) trilobite and brachiopod association has been recovered from the lower part of the volcano-sedimentary Shakshagaily Formation, exposed on the western side of Lake Balkhash in central Kazakhstan. Its discovery demonstrates the presence of Lower Devonian marine deposits in the region. The trilobite assemblage includes representatives of six genera: the dalmanitid Kasachstania alperovichi nov. sp. is the dominant taxon, with other components being Ananaspis?, Leonaspis?, Maurotarion, Trimerus (Edgillia), and Warburgella. Associated brachiopods include species of Glossoleptaena, Leptaena, Protolepstostrophia, Pseudostrophochonetes, and Resserella. Whilst a significant proportion of these taxa show distinct links with the contemporaneous trilobite and brachiopod faunas of the north Balkhash Region, the occurrence of Trimerus (Edgillia) aff. kinglakensis Gill, 1949 suggests a possible link with the Lochkovian trilobite fauna of the Australasian sector of Gondwana. The west Balkhash Region preserves an extensive record of late Silurian to Early Devonian island arc volcanism, slope-rise sedimentation and olistostrome formation, which has invariably been ignored in models favouring early amalgamation of the Kazakhstanian terranes into a single continent by the end of the Ordovician.     

Cystoporida (Bryozoa) from the Emsian Stage (Lower Devonian) of the Salair Ridge and Gorny and Rudny Altai

Eight bryozoan species of the order Cystoporida are described from the Emsian Stage of the Lower Devonian in the western Altai-Sayan Folded Area. Five of them are new species: Fistulipora salairiensis sp. nov., Fistuliramus fasciculus sp. nov., Fistuliphragma sibirica sp. nov., F. moniliformis sp. nov., and Fistulocladia cincinnata sp. nov. The others belong to the genera Ganiella, Physallidopora, and Fistuliporidra. Most of the cystoporid species studied from the Emsian Stage in the Altai-Sayan Folded Area are widespread laterally. Six cystoporid species have a narrow stratigraphic range and are, therefore, characteristic species of the bryozoan biostratigraphic zones of this region. The species of Physallidopora cantabrica Ernst et Buttler and Fistuliporidra hibera Ernst et Buttler, for the first time encountered in the Emsian of Gorny and Rudny Altai, were previously described from coeval deposits in northwestern Spain.     

New Emsian foraminifers from of the Karpinsky Horizon limestones Severouralsk Bauxite Mine

Four new foraminiferal species, Parathuramminites mutilatus sp. nov., P. stelliformis sp. nov., P. subrus sp. nov., and P. minutus sp. nov., and a new genus and species, Algaeformis porosus gen. et sp. nov. from clayey limestones and marls of the basal Karpinsky Horizon (Emsian Stage, Lower Devonian) of the Severouralsk Bauxite Mine are described.     

A new ammonoid fauna from the Carnian (Upper Triassic) Kasimlar Formation of the Taurus Mountains (Anatolia,Turkey)

We describe a new ammonoid fauna from the Taurus Mountains of southern Turkey. The Carnian ammonoid fauna from A?a?iyaylabel is presented for the first time. Ammonoids were obtained from limestone to marl beds of an approximately 35‐m‐thick section, which presents the rare opportunity to investigate ammonoid faunas across the Lower–Upper Carnian boundary. Intense sampling near the village of A?a?iyaylabel led to the recognition of a new Lower Carnian (Julian 2) to Upper Carnian (Tuvalian 1) ammonoid fauna from the Kasimlar Formation. The genus Kasimlarceltites gen. nov. is reported for the first time from the Taurus Mountains, which represents the main faunal element and occurs as huge mass occurrence (n ? 1 million). Kasimlarceltites krystyni gen. et sp. nov., Klipsteinia disciformis sp. nov. and Anasirenites crassicrenulatus sp. nov. occur within the Lower Carnian Carbonate member (Units A–B) of the Kasimlar Formation from the Taurus Platform Units. Ammonoids described from the marls of the Tuvalian Marlstone member were deposited during a major, Tethyan‐wide climate crisis – the so‐called Carnian crisis – characterized by a demise of carbonate platforms. Based on the biostratigraphic relevance of certain ammonoid taxa described herein, the age of the analysed parts of the Kasimlar Formation is Julian 2 to Tuvalian 1. The discovery of the new ammonoid assemblages from A?a?iyaylabel substantiates the significance of Upper Triassic faunas within the Taurus Mountains and facilitates the correlation with faunal assemblages from other regions in the Tethyan Realm. The ammonoid fauna and facies indicate a general deepening from open‐platform margins, over deeper shelf settings down to an open marine‐influenced basinal environment. The tentative habitat for Kasimlarceltites gen. nov. is a shallow platform environment to upper mid‐ramp.     

蒙古南戈壁泥盆纪(埃姆斯期-艾菲尔期)牙形刺

在蒙古南戈壁地区丘隆组(Chuluun Formation)和查干卡勒噶组(Tsagaankhaalga Formation)发现的牙形刺证明丘隆组的时代为晚埃姆斯期,查干卡勒噶组的时代为早艾菲尔期,与以前大化石所确定的时代一致。但艾菲尔阶的底界暂时还无法准确确定,蒙古南戈壁地区艾菲尔阶牙形刺动物群与同期北美的牙形刺动物群相似．但也包含一些地方性分子,蒙古海相艾菲尔期的沉积可能不完整。本文描述了2个命名新种．Caudicriodus delicatus sp. nov. , C. paraculicellus sp. nov. ,一个未命名新种,Caudicriodus sp. nov. A和一个新亚种,Cuadicriodus angustus cauda subsp, nov.。