New Microorganisms from the Gaoyuzhuang Formation of Northern Taihang Mountains,China

A new diverse assemblage of microorganisms has been discovered in black bedded, nodular and lenticular cherts and dark chert of domical stromatolites in dolostone of the Gaoyuzhuang Formation in Lingqiu County, northern Taihang Mountains. The geologic relationships, biostratigraphic correlations, and available radiometric age determinations place the age of the Gaoyuzhuang Formation at approximately 1 400-1 600 million years in age. Eight new species, three unnamed species, and two emended genera of oscillatoriacean, nostocacean, and chroococcacean cyanobacteria are described. These data coupled with reports of others indicate that the diversity of taxa in the Gaoyuzhuang Formation reaches 100 species. The Gaoyuzhuang Formation contains one of the richest Mesoproterozoic communities of microfossils. The following new and emended taxa are described: Oscillatoriaceae: Eophormidium orculiformis sp. nov., E . sp., Siphonophycus caudataceous sp. nov., Palaeolyngbya complanata sp. nov., P. capitata sp. nov., P . sp. and Oscillatoriopsis sp..Nostocaceae: Veteronostocale vaginata sp. nov.. Chroococcaceae: Maculosphaera giganta sp. nov. and Gloeotheceopsis grandis sp. nov. Incertae sedis: Myxococcoides limpida sp. nov.     

华北太行山北段高于庄组微古植物的新发现

长城群高于庄组主要分布于我国华北地区,地质年龄约在14－16亿年。主要描述了华北太行山北段灵邱县境内高于组白云岩中的层状和扁豆状透镜体燧石及穹隆式叠层石的黑色燧石中的颤藻、念珠藻和色球藻植物的8个新种和3个未定种,其中还有两个新修订属。这些新的促群再加上前人在高于庄组地层中已报道的汇成了近100个种生物组合,进一步证明高于庄组地地球上中元代微化石类群最丰富的产地之一。以下是该 新发现和新修订的分类类群：颤藻科（Oscillatoriaceae): Eophormkidium orculiformis sp. nov., E. sp., Siphonophycus caudataceous sp. nov., Palaeolyngbya complanata sp. nov., P. capitata sp. nvo., P. sp., Oscilaltoriopsis sp.;念珠藻科（Nosto-caceae):Veteronostiocale vaginata sp.nov.;色球藻科（Chroococcaceae):Maculosphaera giganta sp.nov.,Gloeotheceopsis grandis sp.nov.;分类位置未定的类群：Myxococcoides limpida sp.nov.。     

Snapshot of an early Paleoproterozoic ecosystem: Two diverse microfossil communities from the Turee Creek Group,Western Australia

Eighteen microfossil morphotypes from two distinct facies of black chert from a deep‐water setting of the c. 2.4 Ga Turee Creek Group, Western Australia, are reported here. A primarily in situ, deep‐water benthic community preserved in nodular black chert occurs as a tangled network of a variety of long filamentous microfossils, unicells of one size distribution and fine filamentous rosettes, together with relatively large spherical aggregates of cells interpreted as in‐fallen, likely planktonic, forms. Bedded black cherts, in contrast, preserve microfossils primarily within, but also between, rounded clasts of organic material that are coated by thin, convoluted carbonaceous films interpreted as preserved extracellular polymeric substance (EPS). Microfossils preserved within the clasts include a wide range of unicells, both much smaller and larger than those in the nodular black chert, along with relatively short, often degraded filaments, four types of star‐shaped rosettes and umbrella‐like rosettes. Large, complexly branching filamentous microfossils are found between the clasts. The grainstone clasts in the bedded black chert are interpreted as transported from shallower water, and the contained microfossils thus likely represent a phototrophic community. Combined, the two black chert facies provide a snapshot of a microbial ecosystem spanning shallow to deeper‐water environments, and an insight into the diversity of life present during the rise in atmospheric oxygen. The preserved microfossils include two new, distinct morphologies previously unknown from the geological record, as well as a number of microfossils from the bedded black chert that are morphologically similar to—but 400–500 Ma older than—type specimens from the c. 1.88 Ga Gunflint Iron Formation. Thus, the Turee Creek Group microfossil assemblage creates a substantial reference point in the sparse fossil record of the earliest Paleoproterozoic and demonstrates that microbial life diversified quite rapidly after the end of the Archean.     

Microfossils in stromatolitic cherts from the upper proterozoic Min'yar formation, southern Ural Mountains, USSR

A diverse assemblage of exceptionally well-preserved microorganisms, including several previously unknown taxa, has been discovered in stromatolitic black chert from the ca. 680-790 Ma-old Min'yar Formation (Suite) of the southern Ural Mountains, USSR. Like most ancient and modern stromatolitic communities, the Min'yar microflora is dominated by filamentous and unicellular cyanobacteria. Geologic evidence indicates that the microbial community inhabited a shallow water, presumably marine environment. The microfossils occur in two interlaminated and thinly interbedded sedimentary fabrics: 1, fact to wavy-laminated Stratifera-like stromatolitic laminae that presumably were deposited during periods of little wave action; and 2, intraclast grainstone that formed as a result of desiccation and (or) wave agitation. Microfossils are both better preserved and more abundant in the intraclasts than in the Stratifera-like laminae. The occurrence of probable pseudomorphs after replacement of sulfate minerals provides additional evidence for a shallow water, periodically emergent depositional environment for the Min'yar microbial mats. Kerogenous microfossils are three-dimensionally preserved, permineralized in fine-grained silica of primary or early diagenetic origin. In many aspects the Min'yar assemblage is comparable to that of the well-known ca. 850 Ma-old Bitter Springs Formation of central Australia. The following taxa are herein described: Division? Schizomycophyta or ? Cyanophyta, Biocatenoides sp.; Family Oscillatoriaceae, Eomycetopsis robusta Schopf emend. Knoll and Golubic, Rhicnonema antiquum Hofmann, Entosphaeroides? sp., Palaeolyngbya? sp., Siphonophycus capitaneum n. gen., n. sp.; Family? Oscillatoriaceae or? Rivulariaceae, Caudiculophycus? sp.; Family? Scytonemataceae or? Stigonemataceae, Ramivaginalis uralensis n. gen., n. sp.; Family Chroococcaceae, Sphaerophycus medium Horodyski and Donaldson, Eosynechococcus amadeus Knoll and Golubic, Gloeodiniopsis lamellosa Schopf emend. Knoll and Golubic, Gloeodiniopsis magna n. sp., Eoaphanocapsa oparinii n. gen., n. sp.; Division? Chlorophycophyta or? Rhodophycophyta, Glenobotrydion majorinum Schopf and Blacic. Also discussed in the taxonomic section, but not formally described, are intermediate-diameter tubular sheaths (Oscillatoriaceae), small tubular sheaths enclosed by larger tubular sheaths (Oscillatoriaceae?), and undifferentiated spheroidal unicells.     

徐淮地区元古宙九顶山组燧石中微体生物化石新资料

我国徐淮地区元古宙九顶山组产出丰富的条带状和结核状燧石,其中保存了大量微体生物化石。本研究通过岩石切片法发现了呈三维立体状态保存的精美的丝状和球状蓝藻化石,鉴定出12属16种,即有丝状蓝藻6属10种(包含2个未定种):Siphonophycus septatum,S.robustum,S.typicum,S.kestron,Oscillatoriopsis ver-miformis,O.obtusa,Cephalophytarion grande,Salome sp.,Veteronostocale amoenum,Paleolyngbyasp.;球状蓝藻3属3种:Gloeodiniopsis suxianensis,Eoentophysalis cumulus,Nanococcus vulgaris;以及分类位置未定的3属3种(包含1个未定种):Myxococcoides minor,Leiosphaeridiasp.,Brachypleganon khandanum。其中Oscil-latoriopsis vermiformis,O.obtusa,Cephalophytarion grande,Salome sp.,Veteronostocale amoenum,Paleolyn-gbyasp.,Nanococcus vulgaris均为本地首次发现,弥补了以前在九顶山组中只找到Siphonophycus而未曾见Os-cillatoriopsis的缺憾,并对大量保存精美的Siphonophycus的来源问题给出了可能的解释。而大量无异形胞的Os-cillatoriopsis属化石的存在可能反映了当时的海底为缺氧环境。本次新发现丰富了九顶山组的微体生物化石资料,这些微体生物化石组合有可能成为元古宙洲际生物地层对比的依据。九顶山组碳酸岩台地沉积相中普遍发育的微体生物藻席、保存精美的高分异度的蓝藻化石以及并未在底栖环境中发现真核生物,均反映冰期前的浅海底栖生态系统还是由原核生物为主体的微体生物生态系统。     

华北高于庄组硅化微体化石组合的古环境

华北中元古代高于庄组 ( 1 4- 1 5亿年 )的硅质叠层石中保存了完好的多种微生物化石。从这些叠层石的微细构造分析 ,成岩早期硅质矿物的交代作用为微体化石的原位保存起了很重要的作用。除部分居住者和浮游的分子外 ,两种丝状蓝藻 ( Siphonophycus inornatum和Eoschizothric composita)和两种球状蓝藻 ( Coccostratusdispergens和 Eoentophysalisbelcherensis)是这些藻席的主要建造者。以球状蓝藻 Eoentophysalis为主的藻席可能发育于潮下高能环境中 ;而以多种丝状蓝藻为主的藻席可能反映了当时的沉积环境为中—高潮间带的局部静止小水体     

台湾地区上下第三系界线划分的孢粉学证据

通过对台湾中部南投县国姓地区北港溪剖面的孢粉样品分析,结合已有的台湾北部基隆地区万里－大武仑露头剖面的孢粉资料,认为台湾地区上下第三系界线置于炭寮地层与十四股层（南投）或公馆凝灰岩与木山层（基隆）之间较为合理。其孢粉组合特征,反映出古气候由晚渐新世经含桤木粉－松粉孢粉组合为特征的寒冷潮湿的北亚热带型向早中新世以含榆科、栎属孢粉组合为特征的温暖湿润的南亚热带型过渡趋势。由于南海北部大陆架北坡的珠海组     

Multi-trichomous cyanobacterial microfossils from the Mesoproterozoic Gaoyuzhuang Formation, China: Paleoecological and taxonomic implications

Populations of the multi-trichomous microbial fossil Eoschizothrix composita n.gen. et sp. are preserved in growth position in silicified stratiform stromatolites of the Gaoyuzhuang Formation, Hebei Province, northern China. The microbial fossils consist predominantly of preserved sheaths, although several specimens retain shriveled remains of trichomes within sheaths. Comparisons with modern morphological counterparts, including shape, growth habit and orientation, degradational sequences, and habitat, support the interpretation of the multi-trichomous microfossils as cyanobacteria, which acted as frame-builders of ancient stromatolites. The distribution and orientation of multi-trichomous microfossils within a synsedimentary context reveal their behavioral responses to sedimentation regime. Horizontally spread, interwoven mats formed during periods of sedimentary stasis. During periods of rapid sediment influx, the filaments assumed an upright orientation, possibly to avoid accumulating particles. This is the first record of fossil stromatolite-building multi-trichomous cyanobacterial which underscores early morphological and functional diversification in cyanobacterial evolution.     

湖北鹤峰白果坪水井沱组（早寒武世）燧石中微化石新资料

湖北省鹤峰白果坪剖面下寒武统水井沱组底部黑色燧石的岩石薄片中,发现有丰富的保存完好的微化石,包括球形藻、刺球藻、丝状藻类及一些分类不明的微化石。经初步研究计有６属９种类型。其中包括１新属Ｓｐｉｃｉｆｏｒｍａｇｅｎ．ｎｏｖ．和２个新种Ｓｐｉｃｉｆｏｒｍａａｇｇｌｏｍｅｒａｔａｇｅｎ,ｅｔｓｐ．ｎｏｖ．和？Ｒｅｔｉｎａｒｉｔｅｓｓｐｉｒａｌｉｓｓｐ．ｎｏｖ．。这一发现进一步丰富了早寒武世早期硅质岩相地层的微体化石资料,为相关地层的对比提供了可资参考的古生物学依据。     

高于庄古生物学(英)

距今 14～ 16亿年的华北地区高于庄组黑色层状、结核状和透镜状燧石与叠层石的黑色硅质部分中保存着极丰富的原核和真核生物微化石。宏观藻类在该组的页岩中亦已发现。本组为评估中元古代生命状况、古环境和前显生宙生物地层提供了重要的生物信息。迄今为止在高于庄组地层中已有百余个化石种被人们认识。根据古植物和古环境的特征这些生物种类可分为三个不同的组合 ,即 :1.颤藻和色球藻组合 ,出现在高于庄组一段 ,代表浅水藻席建造者和居住者与一些可能的外来浮游生物的种类 ;2 .念珠藻组合 ,仅发生在该组的二段 ,还含一些底栖藻席建造者或居住者的种类 ;3.第四段的色球藻组合 ,它代表了潮间带至亚潮带的藻席建造者和外来的种类。元古代燧石中的微化石 ,尤其是蓝藻化石 ,尽管在元古代它们就已不断趋向于多样化 ,但由于它们形态上的保守性 ,对环境的指示比对地质时代的指示更有价值。高于庄组微化石的特点和大多数链状念珠藻垂直层理保存的事实表明 :1.高于庄组微化石的个体大小随时间趋向于增大 ;2 .高于庄组的沉积可能是处于一个淡水环境 ,且沉积率可能等于或少于微生物的生长率 ;3.高于庄组织沉积模式可能是从潮间带至亚潮带或深海 ,然后再至潮间带或潮上带 ;4 .当高于庄组沉积时真核生物亦已出现。     

苏皖北部新元古代微生物化石

苏皖北部新元古代海相泥页岩,粉砂岩及燧石中富含微生物化石,其中,通过化学浸解法,从碎屑岩中获得14个形态属种的微生物化石;6个形态属种的蓝细菌化石呈三维立体状态保存在燧石切片中。浸解获得的泥页岩,粉砂岩相微生物化石,在刘老碑组中-上部的主要是片形和球形：Laminarites antiquis-simus,Leiosphaeridia pelucida,Spumiosa alara及Asperatopsophosphaera bavlinensis;在九里桥组,贾园组和赵圩组主要为多面形和球形;Monilinema quadratucella及Synsphaeridium sp.而史家组,金山寨组和沟后组则有丰富的球形,片形,梭形和带形个体;Leiosphaeridia hyperboreica,Trachysphaeridium simplex,Annulum difuminatum,Nucellosphaeridium asperatum,Tophoporata sp.Symplassosphaeridium sp,Macroptycha uniplicata及Taenia-tum simplex。该微生物组合可与河北及天津蓟县的新元古界景儿峪组和下马岭组的相对比,虽然上述微生物化石的系统古生物学仍在研究中,但却为我们了解新元古代大冰期前夕近岸海相环境生物圈提供了有关浮游植物的信息。苏皖北部新元古代倪园组及九顶山组的燧石中,保存良好的微生物三维立体化石为丝形和球形蓝细菌遗留物,包括Siphonophycus sp,Eoentophysalis belcherensis,Eozygion grande,Tetraphycus conjionceum,Globophycus rugosum及Caryospharoides pristine。该蓝细菌组合可能是底栖的,它们出现在非叠层石的碳酸盐沉积环境。     

A Paleoarchean coastal hydrothermal field inhabited by diverse microbial communities: the Strelley Pool Formation,Pilbara Craton,Western Australia

The 3.4‐Ga Strelley Pool Formation (SPF) at the informally named ‘Waterfall Locality’ in the Goldsworthy greenstone belt of the Pilbara Craton, Western Australia, provides deeper insights into ancient, shallow subaqueous to possibly subaerial ecosystems. Outcrops at this locality contain a thin (<3 m) unit of carbonaceous and non‐carbonaceous cherts and silicified sandstones that were deposited in a shallow‐water coastal environment, with hydrothermal activities, consistent with the previous studies. Carbonaceous, sulfide‐rich massive black cherts with coniform structures up to 3 cm high are characterized by diverse rare earth elements (REE) signatures including enrichment of light [light rare earth elements (LREE)] or middle rare earth elements and by enrichment of heavy metals represented by Zn. The massive black cherts were likely deposited by mixing of hydrothermal and non‐hydrothermal fluids. Coniform structures in the cherts are characterized by diffuse laminae composed of sulfide particles, suggesting that unlike stromatolites, they were formed dominantly through physico‐chemical processes related to hydrothermal activity. The cherts yield microfossils identical to previously described carbonaceous films, small and large spheres, and lenticular microfossils. In addition, new morphological types such as clusters composed of large carbonaceous spheroids (20–40 μm across each) with fluffy or foam‐like envelope are identified. Finely laminated carbonaceous cherts are devoid of heavy metals and characterized by the enrichment of LREE. This chert locally contains conical to domal structures characterized by truncation of laminae and trapping of detrital grains and is interpreted as siliceous stromatolite formed by very early or contemporaneous silicification of biomats with the contribution of silica‐rich hydrothermal fluids. Biological affinities of described microfossils and microbes constructing siliceous stromatolites are under investigation. However, this study emphasizes how diverse the microbial community in Paleoarchean coastal hydrothermal environment was. We propose the diversity is at least partially due to the availability of various energy sources in this depositional environment including reducing chemicals and sunlight.     

高于庄古生物学

距今14～16亿年的华北地区高于庄组黑色层状、结核状和透镜状燧石与叠层石的黑色硅质部分中保存着极丰富的原核和真核生物微化石.宏观藻类在该组的页岩中亦已发现.本组为评估中元古代生命状况、古环境和前显生宙生物地层提供了重要的生物信息.迄今为止在高于庄组地层中已有百余个化石种被人们认识.根据古植物和古环境的特征这些生物种类可分为三个不同的组合,即:1.颤藻和色球藻组合,出现在高于庄组一段,代表浅水藻席建造者和居住者与一些可能的外来浮游生物的种类;2.念珠藻组合,仅发生在该组的二段,还含一些底栖藻席建造者或居住者的种类;3.第四段的色球藻组合,它代表了潮间带至亚潮带的藻席建造者和外来的种类.元古代燧石中的微化石,尤其是蓝藻化石,尽管在元古代它们就已不断趋向于多样化,但由于它们形态上的保守性,对环境的指示比对地质时代的指示更有价值.高于庄组微化石的特点和大多数链状念珠藻垂直层理保存的事实表明:1.高于庄组微化石的个体大小随时间趋向于增大;2.高于庄组的沉积可能是处于一个淡水环境,且沉积率可能等于或少于微生物的生长率;3. 高于庄组织沉积模式可能是从潮间带至亚潮带或深海,然后再至潮间带或潮上带;4.当高于庄组沉积时真核生物亦已出现.     

Microfossils from the Krol ‘A’ of the Lesser Himalaya,India: Additional supporting data for its early Ediacaran age

An assemblage of microfossils of moderate diversity, with the remarkable occurrence of ECAP acritarchs, is reported from the Ediacaran Krol ‘A’ (= the Mahi Formation) succession of Lesser Himalaya, India. Microfossils occur in the chert nodules exposed in Solan district, Himachal Pradesh. Two microfossils, Barogophycus symmetricus n. gen. n. sp. and Botominella lineata are new to the well-established Krol assemblage. The paper concentrates predominantly on fossil eukaryotic filamentous and coccoidal micro-organism of simple morphology. The assemblage is dominated by remains of prokaryotic cyanobacteria and demonstrates the diversity achieved by microorganisms at the beginning of the Ediacaran Period in the aftermath of the Marinoan glaciation. Filamentous and coccoidal microorganisms differ in taxonomic composition from the Mesoproterozoic microbiotas. The Krol microfossils assemblage has biostratigraphic potential and usefulness in broadly demarcating the different levels of the Ediacaran strata. Because of the presence of ECAP acritarchs, along with the appearance of other eukaryotic microorganisms of filamentous and coccoidal morphology, the general level of the Krol ‘A’ assemblage is considered as Ediacaran.     

The stratified microbial community at Laguna Figueroa, Baja California, Mexico: a possible model for prephanerozoic laminated microbial communities preserved in cherts

The microbial mat community of the evaporite flat at North Pond, Laguna Figueroa (Baja California, Mexico) was actively involved in the production of laminated sediments prior to 1978. Heavy rains in 1979 and 1980 flooded the mat with 1 and 3 meters of meteoric water respectively. The flooding deposited up to 10 cm of silicoclastic sediment over the Microcoleus-dominated mat and resulted in the cessation of laminated sediment deposition. In 1982, the surface had been recolonized by species of cyanobacteria (Spirulina, Oscillatoria) and purple photosynthetic bacteria (Chromatium, Thiocapsa). The silicoclastic sediments and residual evaporites, which overlaid the laminated sediment, had been reworked into an anaerobic, sulfide-rich mud and contained well preserved sheaths of filamentous and coccoid bacteria. The Swaziland Sequence in the Barberton mountain land (which includes the Onverwacht and Fig Tree Group as well as the Swartkoppie zone between them) contains laminated sediments and carbon-rich chert. Structurally preserved microfossils have been found in the smooth black chert but not in the laminae. We concur with others who suggested that the laminated sediments from the Swaziland Sequence were deposited by an active stratified microbial community. However, we propose that these organisms which were preserved were originally buried in the associated sulfide-rich muds and were subsequently silicified.     

峡东地区埃迪卡拉系陡山沱组疑源类生物地层序列

峡东地区埃迪卡拉系陡山沱组自下而上可分4个岩性段:第1段为1.5-5m具帐篷和板裂构造的"盖帽白云岩";第2段是90-120m白云质灰岩夹黑色页岩,富含燧石结核;第3段为40-70m的白云岩夹燧石层和燧石结核;第4段10-20m为黑色碳质页岩夹碳酸盐岩透镜体.根据对该区九龙湾、王丰岗、田家园子、九曲脑、晓峰河、樟村坪等多条陡山沱组剖面的重新调查,确认第2和第3段分别含有不同的疑源类组合,二者被之间出现的δ13C负漂移(EN2)所分隔.下组合以Tianzhushania和高分异的具刺疑源类出现为特征.上组合与下组合的区别是:(1)Tianzhushania绝迹;(2)出现大量表面光滑,介于90-150μm的球状膜壳;(3)高分异的具刺疑源类既包括下伏上延的种类,又含有首次出现的新类型;(4)还出现可能为单细胞原生动物的微化石;(5)管状化石震旦圆圆茎(Sinocyclocylicus guizhouensis)首现.     

北京延庆地区雾迷山组燧石相微体古生物研究

本文报道的微体化石产于北京延庆地区雾迷山组中的燧石相岩层中,共鉴定出10个属19个种,其中含1个新种,3个未定种,以及2个相似种。化石类型以蓝细菌中的颤藻科、念珠藻科和色球藻科属种为主,还保存有少量绿藻和大量分类位置未定的藻类。新的化石资料必将进一步丰富燕山雾迷山组的微化石群的内容,并为进一步评价雾迷山组微化石的生物演化和多样性的水平,及其生物地层意义提供更充分的依据。     

Palynomorphs from the Cambrian Series 3, Parahio valley (Spiti), Northwest Himalaya

We present low-diversity acritarch assemblages, including Alliumella baltica, Bavlinella faveolata, Brocholaminaria nigrita, Brocholaminaria sp., Eliasum sp., Leiosphaeridia minutissima, Leiosphaeridia spp., Lophosphaeridium sp., Pterospermella solida, Satka colonialica, Siphonophycus sp., and Synsphaeridium sp., as well as filamentous algae and cryptospore-like microfossils recorded from 45 rock samples around the Oryctocephalus indicus Zone (Cambrian Series 3) in the Cambrian Kunzam La (Parahio) Formation at the Kaltarbo locality in the Parahio valley, Northwest Himalaya. One new species Synsphaeridium parahioense was established. The acritarch assemblages at the basal part of the Cambrian Series 3 in the Kunzam La (Parahio) Formation were dependent on the local marine environment. The new discovery of cryptospore-like microfossils from the Cambrian Kunzam La (Parahio) Formation supports the extensive distribution of possible cryptospores in the Cambrian stratigraphic sequences.     

新元古代陡山沱组具细胞裂殖结构的丝状蓝藻

新元古代陡山沱组丝状蓝藻化石Oscillatoriopsis sp.,具丝状蓝藻化石记录中罕见的细胞分裂结构;其胞壁内陷的二等分裂方式,可能的丝体断裂结构。是现生丝状蓝藻生长和繁殖的典型特征;不具异形胞结构的形态特征,可能与其当时生存的海底表面的缺氧环境有关;这种基底环境,可能有利于Oscillatoriopsis sp。等磷酸盐化化石细节构造的保存。     

Cyanobacteria or rhodophyta? Interpretation of a precambrian microfossil

Discovery and interpretation of a filamentous microfossil from the late Proterozoic Narssarssuk Formation in northwest Greenland approximately 770 Ma is reported here. This microfossil is preserved as a single occurrence in a silicified carbonate sequence containing stromatolitic laminae. Based on the absence of other occurrences and its microstratigraphic association with planktonic microfossils, the microfossil is interpreted as allochthonous. The microfossil is similar to two extant taxa representing different kingdoms: one prokaryote, Johannesbaptistia pellucida (cyanobacteria) and one eukaryote, Bangia sp. (rhodophytes). Definitive identification, due to the lack of distinctive morphology, could not be made.