New observations on the Lower Carboniferous pteridosperm Diplopteridium Walton and an associated synangiate organ

New material of Diplopteridium holdenii is described from the Drybook Sandstone assemblage of Upper Visean (Middle Mississippian) age at Puddlebrook, Gloucestershire. Vegetative leaves consist of bifurcate fronds which are pinnately divided and terminate in narrow pinnule segments. The fronds are arranged spirally in terminal crowns on a narrow, spindly axis. Fertile leaves consist of fronds which bear a median, dichotomous branchlet which gives rise to reflexed, bilaterally symmetrical cupules. One specimen demonstrates that a single fertile crown consisted of cupulate and vegetative fronds. The detailed morphology of the cupules is reconstructed from compression/impression and fusainized material from both attached and isolated units. An isotomously branched synangiate organ is also described from the locality. The synangiate organ is assigned to a new genus and species. A comparison of D. holdenii and this synangiate organ with Diplopteridium teilianum from north Wales and Sphenopteris bifida and Sphenopteris affine from northern England and Scotland, provides indirect evidence that the synangiate organ may have belonged to D. holdenii . Bifurcate and trifurcate fronds associated with dichotomous branchlets bearing either synangial or cupulate structures was a common association in the Visean compression assemblages of Great Britain.     

Microstructure de CladochonusMcCoy, 1847(Tabulata,Carbonifère)

The microstructure of two species of Cladochonusfrom Algerian Carboniferous, C. crassus (McCoy) and C. cf. tenuicollisMcCoy, has been studied by ultra-thin sections. Their walls consist of: 1. an external fibrous layer, 2. a median layer of undulating lamellae, 3. an internal zone of slender, elongated elements to which the name of «grundulae is given here. New data bring complements to the generic diagnosis of Cladochonus s. str. Some Permian cladochonid forms show different microstructures and should, therefore, be shifted to new generic units.     

藏北申扎地区下石炭统永珠组下部孢子组合的特征及意义

报道藏北申扎永珠区德日昂玛—下拉剖面的永珠组孢子组合,发现孢子43属,70余种(包括未定种)。组合特征如下:1)缺乏欧美植物地理区早石炭世典型的石松类植物的小孢子Lycospora属及早石炭世晚期(维宪期)重要孢子属;2)出现较多早石炭世早期(杜内期),甚至泥盆纪晚期分子。呈现出新老化石的混合现象;3)北半球和南半球孢子的混合组合,同时也是冷、暖微古植物群混合,既有相当于中国早石炭世晚期大塘期以及西欧维宪期典型属种,又有南半球澳大利亚(包括巴西和非洲大陆)的维宪期的典型种。从孢子化石混合现象看,永珠组应为近岸浅水或滨海条件下的沉积,下伏地层的孢子化石再沉积现象说明当时有一次很大的海平面下降,在邻近地区出现了大面积的剥蚀区。说明杜内期末期—维宪期初期,申扎地区出现一次由冈瓦纳大陆冰川发育造成海平面相对下降。形成区域上不整合界面———洛工组或“巴日阿朗寨段”底部的不整合界面。混合孢子组合中的寒冷气候条件下的孢子化石的发现,印证了杨式溥、范影年和林宝玉推断的冈瓦纳冰川自早石炭世维宪期(大塘期)开始就影响到西藏申扎的推论。     

Lower Carboniferous (middle Visean) foraminifers and algae from an interior sea,Southern Carnarvon Basin,Australia

A moderate diversity biota of foraminifers, algae and calcareous microproblematica is recorded from the Lower Carboniferous Yindagindy Formation within the intracratonic Southern Carnarvon Basin in Western Australia. Very shallow metahaline to hypersaline conditions are suggested. The palaeobotanical components are sporadic calcitarcha, tuberitinaceans, codiaceans Orthriosiphon? sp. 1, dasycladaleans? Koninckopora tenuiramosa, and algosponges Issinella devonica, Serrisinella cf. serrensis, Issinella? sp. 1, Kamaena cf. awirsi, Proninella? sp. and Stacheoides spp. The foraminiferal assemblage is dominated by a new koktjubinid taxon: Praekoktjubina yindagindyensis nov. gen., nov. sp. Subordinate associated foraminifers are more sporadic Salpingothurammina? sp. 1, Plectinopsis michelseni nov. gen., nov. sp., Rectopravina multifida nov. gen., nov. sp. (with 4 morphotypes), and scarce Endothyra spp. Despite many of these taxa being endemic, a middle Visean age is probable, based on: (1) the maximum global geographic extent of K. tenuiramosa reached during the middle Visean, (2) the disappearance of Plectinopsis nov. gen. in Palaeotethys and the Urals, and (3) the first occurrence of Praekoktjubina nov. gen. in Palaeotethys. An age no older than the middle Visean is supported by sparse conodonts from the Formation and comparison to episodes of carbonate deposition in the Bonaparte Basin, further north in the East Gondwana rift system. Absence of middle Visean archaediscoids may be due to high salinity. The following algal and foraminiferal families and superfamilies are emended: Scribroporellaceae (a lectotype is selected for Orthriosiphon saskatchewanense); Palaeospiroplectamminidae (due to the creation of Plectinopsis nov. gen.); Haplophragminoidea (due to the creation of Rectopravina nov. gen.); and Globivalvulinoidea and Koktjubinidae (due to the creation of Praekoktjubina nov. gen.).     

A new lycopod, Novgorodendron conophorum gen. et sp. nov., from the Lower Carboniferous of the Moscow Syneclise

A new lycopod, Novgorodendron conophorum gen. et sp. nov., is described from the Upper Visean deposits of the Kamenka River, near the town of Borovichi (Novgorod Region). The morphology of the leaf cushions of the new plant implies its intermediate position between the families Sublepidodendraceae Chaloner et Boureau and Lepidodendraceae Endlicher. The bases of the leaf cushions have peculiar conical appendages, a previously unknown morphological feature not recorded from other lycopods. We propose the term basal conical appendages for them. The interpretation of some epidermal elements in the leaf cushions of the Lepidodendraceae is revised. The structures of the leaf cushions that were previously treated as either stomata or cells with cystoliths are shown to be sunken multicellular trichomes.     

High-resolution biostratigraphy of the Tournaisian-Visean (Carboniferous) boundary interval, Mokrá quarry, Czech Republic

This paper summarizes the results of investigations carried out in the Mokrá quarry since 2006 on the biostratigraphy of the Tournaisian-Visean (T-V) boundary interval. It also integrates previous results obtained by J. Kalvoda and collaborators. The main focus is on the boundary itself, but stratigraphically lower and higher levels have been investigated as well to provide a biostratigraphical context spanning the late Tournaisian to early Visean. This stratigraphical level has been the focus of intense international research in the recent years under the auspices of the Subcommission on Carboniferous Stratigraphy (SCCS) in order to find a new criterion and reference section (Global Stratotype Section and Point, GSSP) for the base of the Visean Stage. The appearance of Eoparastaffella simplex from its ancestor E. “ovalis” and the Pengchong section (Guangxi, southern China) have recently been proposed by the Task Group on the Tournaisian-Visean Boundary and ratified by the SCCS as the new biostratigraphic criterion and GSSP for the base of the Visean, respectively. The sequence exposed in Mokrá is not suitable as a GSSP, notably because it is an active quarry, but it contains most of the foraminifer and conodont guides allowing a high-resolution biostratigraphy of the boundary interval. In addition, it contains abundant trilobites. For these reasons, it constitutes one of the best sections across the T-V boundary in Europe and can serve as a useful additional reference.     

甘肃靖远、景泰早石炭世维宪期植物群

祁连山和河西走廊区石炭纪地层发育,动植物化石丰富,是研究我国海陆交互相石炭系的重要地区。臭牛沟组系袁复礼(1925)所建,标准地点在甘肃武威西南35km的臭牛沟,据其中的腕足类和珊瑚化石的研究,确定其时代为早石炭世维宪期(Visean)。研究材料来自甘肃景泰和靖远的早石炭世臭牛沟组,这里的臭牛沟组厚约120m左右,由泥质页岩夹煤线、粉砂岩及薄层泥灰岩、灰岩组成,为潮间潟湖相至滨海沼泽相及泥炭沼泽相沉积。含丰富的植物化石,主要分子有Sublepidodendron sp. , Lepidodendronciyaoense sp. nov. , Lepjingyuanense sp.nov. , Lepidodendron volkmannianum , Lep. gansuense sp. nov. , Lep. shanyangense, Lep. cf. aolungpulukense,Lep. sp. 1, Lep. sp. 2, Cathaysiodendron jingyuanense, C. cf. incertum, Stigmaria ficoides, Lepidostrobophyllum cf. lanceolatum, L. rotundi folium sp. nov., Lepidostrobus sp. 1, L. sp. 2, Bothrodendron ruchengense, Archaeocalamites scrobiculatus , Hamatophyton uerticillatum , Cardiopteridium spetsbergense , C. podozamioides,Triphyllopteris collombiana , Triphyllopteris sp. ( cf. T. lescuriana Lesquereux), Rhacopteris sp. , Adiantites gothanii, Sphenopteris sp. 1, Sphenopteris sp. 2, Rhodeopteridium hsianghsiangense, R. cf. hsianghsiangense,R. cf. chinghaiense, Rhodeopteridium sp. (cf. R. lipoldi) , Paripteris gigantea , P. cardiopteroides, Linopteris sp. , Codonospermum sp. , Trigonocarpus spp. , Cardiocarpus cordai, Cordaites sp. (cf. C. schenkii Halle) 。其下伏地层前黑山组中有菊石Kazakhstania sp．,为下石炭统底部Gattendor fia带分子,其余还有孢子化石、腕足类和植物,表明为杜内期沉积;而上覆地层靖远组底部有牙形石Gnathodus bilineatus bollandensis,G．bilineatus bilineatus,Paragnathodus commutatus及P．nodosus,是我国下石炭统顶部德坞阶的一个牙形石带化石;筵化石：Mediocris breviscula,M．pilatus,M．cf．minima,Eostaffella galinae,E.cf．mediocris是我国和卅l组常见分子,也产于贵州罗甸的德坞阶(相当于早期纳缪尔阶)。臭牛沟组产有大量孢子,可分3个孢子带,分别可以和西欧维宪期孢子带(PV,TC,NM)对比。在当前的植物群中Cathaysiodendron及Bothrodendron ruchengense,Le pidodendron shanyangense的发现,对于研究早石炭世植物地理区的划分,华南和西北同期植物群的对比及东方型鳞木类的演化均具有重大意义。     

Depth-related ecological zonation of a carboniferous carbonate ramp: Upper Viséan of Béchar Basin,Western Algeria

Summary Following the demise of the stromatoporoid-coral reef community in Late Frasnian time, Lower Carboniferous carbonate shelf profiles possessed a ramp geometry, with major organic buildups represented by mud-rich mounds. Microfacies petrography of the exceptionally well-preserved Upper Viséan (Lower Carboniferous) carbonate ramp of the Béchar Basin, Algerian Sahara, may well contribute significantly to our understanding of the paleoecological zonation of Carboniferous non-rimmed platforms, and of the still enigmatic mounds commonly referred to as Waulsortian banks or mounds. Facies are grouped into two broad groups: (a) a mound facies group which comprises sponge wackestone-bafflestone, sponge-fenestellid bafflestone-wackestone, crinoid wackestone-packstone, and bedded flanks of intraclastic wackestone-packstone, all four facies composing the actual mud-rich mounds, and (b) a supramound facies group composed of coral-microbial framestone, crinoid packstone-grainstone, algal-foraminiferal grainstone and oolite grainstone. Calcareous algae are important bathymetric indicators and are used to delineate three bathymetric zones based on light penetration: the aphotic zone, which contains no calcareous algae; the dysphotic zone, where there is little ambient light, and which is characterized by the presence of red algae (Fasciella, Ungdarella, Stacheia, Epistacheoides) and absence of green algae; and the euphotic zone, which receives the full spectrum of sunlight, and is characterized by the occurrence of both green algae (Koninckopora, Kamaenella, Kamaena, Palaeoberesella, Calcisphaera, Anthracoporellopsis, Issinella, Exvotarisella) and red algae. Integration of algal zonation, distribution of the other biota, and recurrence of distinct assemblages, enable recognition of seven depth-related benthic assemblages. Together with the physical properties of the facies, the benthic assemblages were used to define seven bathymetric zones, from upper to lower ramp: (1) algal assemblage (upper ramp); (2) crinoid-ramose bryozoan assemblage (mid-ramp); and (3) productid brachiopod assemblage, (4) colonial rugose coral-microbial encruster assemblage, (5) crinoid-fenestellid assemblage, (6) sponge-fenestellid, and (7) sponge assemblage (lower ramp). The vertical zonation of the mud-rich mounds and associated facies differ from that reported from the classical Upper Tournaisian-Lower Viséan Waulsortian mound-bearing successions.     

湖南异珊瑚目的新材料——兼论异珊瑚目的构造

记述了湖南渣渡早石炭世维宪期异珊瑚6属: Hexaphyllia, Pentaphyllia, Haptaphyllia, Heterophyllia, Nodohexaphyllia gen. nov. 及 Nodopentaphyllia gen. nov..根据这些珊瑚的内部构造形态,特别从出芽繁殖幼体的构造形态,对异珊瑚轴管的形成、横板的生长形态、隔壁的生长起点及体壁组成的因素等提出了一些新的见解.     

Diploporaceae (calcareous green algae dasycladales) from the late Visean (Mississippian) of Montagne Noire (southern France)

The Montagne Noire limestones are rich in late Visean (Mississippian) dasycladales and the locality of Cabrières in particular has been famous for over 30 years for the Diploporaceae (metaspondyl dasycladales). New Diploporaceae are described, in order to introduce the necessary nomenclature for future studies. The following new taxa are described: Windsoporella solida, n. sp., W. longirostris n. sp., Cabrieroporinae n. subtrib., Kulikiinae n. subtrib., Borladellinae n. subtrib., Guadiatella heraldica n. sp., Murvielipora n. gen., Murvielipora aretzii n. gen. n. sp., Cabrieroporellopsis n. gen., Cabrieroporellopsis inopinatus n. gen. n. sp. The emended taxa are Windsoporella, W. tulayae, Kulikia and Cabrieropora.