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1.
《Palaeoworld》2015,24(3):293-323
A diverse assemblage of plant macrofossils and the associated representative palynofloral elements are documented from the early Eocene subsurface beds of the Cambay Shale Formation exposed in an open cast lignite mine at Vastan Village in the Surat District, western India. The Vastan mine succession is cyclic, each cycle representing a transgressive burial event terminating in the low energy lagoonal conditions. The higher energy cycle begins with sandy lenses having rich biotic remains, followed by mudstones and molluscan shell beds and ends with lignite seams. The dominantly muddy facies and the associated biota demonstrate predominantly low energy near shore or coastal plain depositional setting with conditions varying from dominantly marine (shallow) through brackish to fresh water. The Vastan mine is a well dated fossil locality with a rich and diverse biota of mammals, birds, snakes, lizards, fish, insects, molluscs, foraminifers, dinoflagellates, and plants. The plants comprise leaf and fruit impressions, seeds, fruits, wood fragments, mangrove rooting structures, fungal thalli and spores, pteridophytic spores, and angiosperm pollen grains. Thirteen macrofossil species, including several morphotaxa, are represented by the families Calophyllaceae, Rutaceae, Anacardiaceae, Rubiaceae, Combretaceae, Lythraceae, Sapindaceae, Malvaceae, and Ebenaceae. The palynological assemblage representing fourteen taxa includes the new species, Notothyrites undulatus, Callimothallus semicircularis, and Carallioipollenites integerrimoides. Habitat and distribution of modern taxa comparable with the fossil assemblage from Vastan suggest a terrestrial lowland environment. The macrofossil taxa are indicative of mesophytic, mixed forest growing under tropical to subtropical climate with sufficient humidity. The occurrence of dipterocarp elements along with taxa such as Swintonia, Pterospermum and Diospyros, etc. seems to suggest the presence of a tropical rain forest in the vicinity of Vastan.  相似文献   

2.
The Cintura Formation of Albian–Cenomanian age in the Cabullona Basin yielded an important fossil flora, including palynomorphs, leaf impressions and fossil trunks. At the base of the Marquechi Member a poorly preserved palynomorph assemblage is recognised. The palynological assemblage is dominated by gymnosperms, mainly by cheirolepidiacean genus Classopollis. A noteworthy feature is the presence of angiosperm pollen grains of the genera Clavatipollenites, Retimonocolpites and Tucanopollis. A rich, diverse and well-preserved macroflora of leaf impressions has been observed in the uppermost part of this formation belonging to the San Juan Member. There are at least eight morphospecies of leaves including an abundance of taxa with possible botanical affinities to the family Sapindaceae. The angiosperm pollen grains together with the sapindalean leaves constitute the oldest record of such remains in Mexico.  相似文献   

3.
Floral remains are generally rare in the fossil record of Pakistan. We present here new discoveries of mid-Cenozoic wood and pollen of Oligocene deposits from central Pakistan. The palynological sample derives from claystone stratigraphically positioned above the wood fossils, but pollen and spores as well as the wood are all of Oligocene age. The three fossil wood samples derive from the top of the lower unit of the Chitarwata Formation, and the palynological sample comes from claystone situated in the middle unit of the formation. The wood samples are described and found to represent two species of the morphotaxon Terminalioxylon (Combretaceae): T. burmense Mädel-Angeliewa and Müller-Stoll [Madel-Angeliewa, E., Müller-Stoll, W.R., 1973. Kritische Studien über fossile Combretaceen-Hölzer: über Hölzer von Typus Terminalioxylon G. Schönfeld mit einer Revision der bisher zu Evodioxylon Chiarugi gestellten Arten. Palaeontographica 142B, 117–136.] and T. sulaimanense sp. nov. These fossils are close to modern species of Terminalia, which occur in moist deciduous or semi-evergreen tropical forests. The palynological assemblage is composed of a mixture of pollen and spore types from different origins. There is a dominance of hygrophilous ferns, pines, Amaranthaceae–Chenopodiaceae–Caryophylaceae, but also the occurrence of Palmae, which are typical of tropical rainforests. This assemblage suggests that the depositional system is set in a context of nearby mountains with a minimum altitude of 2000 to 2500 m and characterized by differentiated forest belts above the tropical lowland vegetation of lower elevations. Wood, pollen and spores support the view of a fluvial environment surrounded by a tropical forested habitat. The separate stratigraphic position of the pollen assemblage above the fossil wood could explain its slightly different, more varied, palaeoenvironmental signal.  相似文献   

4.
A well-preserved macroflora and rich palynological assemblages corresponding to the Camarillas Formation (early-middle Barremian) in the San Cristóbal and Galve Mine sites from the Galve sub-basin in northeastern Spain are presented here. These remains represent the first fossil plant evidence from these deposits. Within plant macroremains, the cheirolepidiacean Pseudofrenelopsis aff. varians (Fontaine) Watson has been found. The palynological assemblage yielded well-preserved spores and pollen grains, mainly dominated by the genus Classopollis. Spores are also abundantly represented by schizaeacean spores (Cicatricosisporites and Plicatella). This spore assemblage supports an early-middle Barremian age for these localities. It is noteworthy that small basal angiosperm pollen grains of the genera Crassipollis and Retimonocolpites, together with other indeterminate grains, have been reported here. This flora constitutes the primary food producer for dinosaur at that time, and thus the information of the flora is important for the understanding of the ecological background for the dinosaur evolution during the Early Cretaceous.  相似文献   

5.
内蒙古东胜中侏罗世延安组孢粉组合   总被引:2,自引:0,他引:2  
研究了内蒙古东胜罕台川、碾盘梁沟和柳沟 3个剖面中侏罗世孢子花粉化石 34属 6 3种 ,包括 2个新种。基于 10个样品中发现的 386 3粒孢子花粉化石的鉴定和统计 ,建立东胜地区延安组孢粉组合。该组合中蕨类植物孢子有 19属 37种 ,含量占 46 %~ 49% ,最低为 39%。裸子植物花粉略占优势 ,有 15属 2 6种 ,含量为 5 1%~ 5 4% ,最高达 6 1%。与国内外相关资料对比结果表明该孢粉组合的地质时代应属中侏罗世巴柔期。孢粉植物群反映研究区在中侏罗世早期为暖温带或亚热带的暖湿气候  相似文献   

6.
In July 1994, we were able to collect airborne fungal spores and pollen grains over the Adriatic Sea from the upper deck of the Oceanographic Ship Urania (CNR). The biological particles were collected using a modified Lanzoni VPPS 1000 sampler (operating at a flux of 10 LPM), on glycerine-gelatine coated microscopic slides. Not only were the airborne concentrations of different organisms estimated, their viability was also tested with a 1% TTC solution. Particles were collected for 60 min (i.e. a volume of 600 liters of air sampled) at every 2 h from 0600–2100 h. Up to 689 pollen grains/m3 and an impressive 48 990 spores/m3 were collected daily. Forty-two fungal taxa were identified and the most abundant spores collected were Cladosporium (82.6%), Smuts (4.8%), Ascospores (2.8%), Basidiospores (2.1%) andAlternaria (1.7%). 20 pollen taxa were identified, and the dominant pollen were Urticaceae (57.9%), Graminaceae (20.7%), Fagaceae (2.4%), Plantaginaceae (1.4%), Pinaceae (1.3%) and Eucalyptus (1.1%). The most abundant captures were done at 0800 and 1000 h (17.8 and 16.7% respectively) and at 1400 and 1600 h (13.2 and 13.8% respectively). Pollen viability per species ranged from 0 to 100%, but for the most abundant taxa, it ranged from 3.8 to 75%, and averaged 27.7%. Maximum viability was found at 0800 and 1200 h. Pollen concentrations were of the same order of magnitude as the ones found on the mainland (Brindisi, Chieti, Matera). However, its specificity was evident. Future work should therefore look more at the pollen transport process which should account for this different assemblage of pollen.  相似文献   

7.
辽河盆地大民屯凹陷沈249井早白垩世九佛堂组孢粉组合   总被引:1,自引:1,他引:0  
沈249井九佛堂组孢粉材料是目前所知辽河盆地孢粉类型最丰富、数量最多且保存最完好,可确定63属,包括蕨类植物孢子40属和裸子植物花粉23属;根据孢粉组合特征,可称其为Cicatricosisporites Concavissimi sporites Classopollis孢粉组合,具有裸子植物花粉相对含量明显较高、分异性较低,而蕨类植物孢子分异性明显较高、相对含量较低的特点;该组合与辽西九佛堂组、内蒙古二连盆地赛汉塔拉组一段的孢粉组合具有很强的一致性。本文资料可弥补辽河盆地九佛堂组孢粉组合的空白,并为深入认识我国北方区九佛堂组沉积时期植物群特征提供重要的帮助。  相似文献   

8.
In July 1994, we were able to collect airborne fungal spores and pollen grains over the Adriatic Sea from the upper deck of the Oceanographic Ship Urania (CNR). The biological particles were collected using a modified Lanzoni VPPS 1000 sampler (operating at a flux of 10 LPM), on glycerine-gelatine coated microscopic slides. Not only were the airborne concentrations of different organisms estimated, their viability was also tested with a 1% TTC solution. Particles were collected for 60 min (i.e. a volume of 600 liters of air sampled) at every 2 h from 0600–2100 h. Up to 689 pollen grains/m3 and an impressive 48 990 spores/m3 were collected daily. Forty-two fungal taxa were identified and the most abundant spores collected were Cladosporium (82.6%), Smuts (4.8%), Ascospores (2.8%), Basidiospores (2.1%) andAlternaria (1.7%). 20 pollen taxa were identified, and the dominant pollen were Urticaceae (57.9%), Graminaceae (20.7%), Fagaceae (2.4%), Plantaginaceae (1.4%), Pinaceae (1.3%) and Eucalyptus (1.1%). The most abundant captures were done at 0800 and 1000 h (17.8 and 16.7% respectively) and at 1400 and 1600 h (13.2 and 13.8% respectively). Pollen viability per species ranged from 0 to 100%, but for the most abundant taxa, it ranged from 3.8 to 75%, and averaged 27.7%. Maximum viability was found at 0800 and 1200 h. Pollen concentrations were of the same order of magnitude as the ones found on the mainland (Brindisi, Chieti, Matera). However, its specificity was evident. Future work should therefore look more at the pollen transport process which should account for this different assemblage of pollen.  相似文献   

9.
The Red Beds of Nandian consists mainly of red mud stone, marlite, quartzitic sand- stanc, Sabulous psephyte and fine psephyte. Predecessor divided them into three formations referring to Upper Triassic-Jurassic. The marlite in Upper Formation of the Red Beds are rich in fossil Sporo-pollen. The fossil spores and pollen contain 17 genera and 15 species, including 3 new species and 2 new combinations. The Sporo-pollen assemblage is characterized by the absolut predominance of the pollen of gymnospcrms (84.8%) compared with the spores of pteridophyta (15.2%), The pollen are specially characterized by the abundance of Classeopollis Pfiug (75.3%) with a certain amount of Psophosphaera (4.5%), Monosulites (2.4%) and a minority of Pinuspollenites (0.6%). The spores grains are characterized by the abundance of Cyathidites (4.1%), and also by presence of Calamospora (2.1%), Reticulatisporitcs (2.4%), Indeterminable form (1.2%), and rare Schizaeisporites (0.3%). Based on the sporo-pollen assemblage of Upper Jurrassic of the Eurasia continent is characterized by the absolute abundance of Classpollis Pflug (>50% of the total number), the Upper Formation oi the Red Beds of Nandian may be referred to Upper Jurassic age. The climate of the Nandian region in the Late Jurassic period is supposed to be as arid as that of Africa at the present time. Bundary of the eastern termination of southern part of the Eurasia continent in- ferred by Vakhrameev (1970) should be complemented.  相似文献   

10.
Apart from the few works carried out in the North Tethyan basins, the palynological study of Mesozoic outcrops is still rare. Thus, the present study devoted to the Zahra Marls Formation (upper Bajocian) of the Rhar Roubane Mountains (northwestern Algeria), allowed us for the first time to inventory 44 different taxa. The palynological assemblages studied are strongly dominated by trilete spores (17 genera and 26 species), the most abundant of which are Concavissimisporites variverrucatus, Cyathidites australis and Cyathidites minor. Pollen grains are relatively frequent (10 genera and 16 species), while acritarchs and algae are represented by only two taxa (Micrhystridium sp. and Botryococcus sp.). In addition, the sporopollinic spectra dominated by the terrestrial elements are represented mainly by the spores of Pteridophyta and Bryophyta and gymnosperm pollen.  相似文献   

11.
This paper shows fossil spores and pollen grains from Cretaceous (Upper Campanian) of Sakhalin, Russia, with scanning electron microscopy. A total of 520 palynomorph assemblages consisting of 25% spores of pteridophytes and bryophytes, 4.5% of ephedroid pollen grains, 6.5% of coniferous pollen grains, and 64% of angiospermous pollen grains were recovered in the present study. 5 genera of pteridophytes, 4 genera of gymnosperms, and 18 genera of angiosperms are described in the present study. The frequent and representative genera from the stratum areEphedripites, Liliacidites, Clavatipollenites, Tricolpites, Aquilapollenites, andAzonia. A new genus,Sciadopitipollenites, that is comparable with extantSciadopitys is proposed in the present study. Polycolpate pollen with the same exine sculpture ofClavatipollenites suggests a generic differentiation in the Chloranthaceae during the Cretaceous age. The diverse spores and pollen paleoflora shown in the present study suggests a wide diversification of angiosperms in the Upper Campanian at the eastern side of Laurasia (Aquilapollenites province).  相似文献   

12.
The geological record of mangrove plants is based on comparablemorphological characteristics of pollen, fruits and wood, of fossil andmodern species. But this record relies on the assumption that the ecologicaland habitat preferences of ancestral taxa have remained similar throughages. A reexamination of fossil evidence of Avicennia, Pelliciera,Sonneratia, Rhizophora, Bruguiera, Ceriops, etc.reveals that the modern mangrove flora was pantropic by the Eocene, andappears to have originated during Paleocene times. Earlier Paleozoic andMesozoic candidates for a mangrove ecology lack conclusive evidence oftheir exclusive association with tidal environments. It is therefore clear thatcontinental drift had a limited role in the dispersal and development ofmodern mangrove floras. The Eocene/Oligocene boundary crisis appears toherald a beginning of the biogeographic split between the current-dayeastern and western provinces of mangrove plants. But, while the climaticorigins of this major disjunction is not clearly understood, our reassessmentof Tertiary paleoclimates suggests that the major cooling events of themiddle Paleocene, the end of the Eocene and the middle Pliocene were themost likely influences on the evolution of mangrove floras. The associatedinvertebrates, especially molluscs, further support our assertion that amodern mangrove ecosystem was established only during the earliestEocene times. We summarize our interpretation in a set of 9 palinspasticmaps of fossil mangrove genera through their evolution ending with thecurrent, bipartite distribution of present day taxa.  相似文献   

13.
Eighty-eight species of spores and pollen referred to 66 genera including one new species from the Fuxian Formation in Yulin-Hengshan region of Shaanxi province have been studied. The sporo-pollen assemblage may be dividied into two subassemblages. The main characters are described as follows: There are 30.7% of spores of pteridophyta. The pollen grains of gymnospermae arno:rots for 69.3%. Among the spores, those of the genus of Deltoidospora (9.2%), Cyathidites (5.6%) and Undulatisporites (4.6%) are dominant, Among the pollen grains, those of the genus Classopoilis of Chiolepidiaceae is predominant (41.8%) and Chasmatosporites(6.1%) are comparatively abundant. Besides these, there are some other Jurassic common species found in the assemblage. Comparing with the known assemblages of other places, the author considers that the Fuxian Formation belongs to Early Jurassic Lias Series. The lower part of the formation might correspond the Hettangian stage or the Simemurian Stage It: the early Jurassic, the climate should be comparatively humid with flourishing vegetation in the early stage, and hot and arid in the middle-late stage.  相似文献   

14.
对四川盆地东北缘宣汉七里峡剖面须家河组进行了详细的孢粉学研究,发现丰富的孢粉化石,共计59属113种,其中包括蕨类植物孢子35属62种,裸子植物花粉22属47种,苔藓类植物孢子1属3种,以及藻类化石1属1种。据此建立一个孢粉组合,命名为Dictyophyllidites-Lunzisporites-Chasmatosporites组合(简称DLC组合),并进一步分为上、下两个亚组合。根据孢粉组合内一些重要分子的地质时代延限及与国内外有关孢粉组合的对比,提出其地质时代属于晚三叠世诺利期—瑞替期(Norian—Rhaetian)。该孢粉植物群反映了一个以蕨类植物的真蕨类、石松类和裸子植物的松柏类和苏铁类群等占主导且较为繁盛的植被面貌,揭示出温暖潮湿的亚热带—热带气候环境。  相似文献   

15.
Many of the oldest definitive members of the Rosaceae are present in the Eocene upland floras of the Okanogan Highlands of northeastern Washington State and British Columbia, Canada. Over a dozen rosaceous taxa representing extant and extinct genera of all four traditionally recognized subfamilies are known from flowers, fruits, wood, pollen, and especially leaves. The complexity seen in Eocene Rosaceae suggests that hybridization and polyploidy may have played a pivotal role in the early evolution of the family. Increased species diversity and the first appearance of additional modern taxa occur during the Late Paleogene in North America and Europe. The Rosaceae become increasingly important components of fossil floras during the Neogene, with taxa adapted to many habitats.  相似文献   

16.
陕西彬县地区中侏罗世延安组孢粉植物群及其意义   总被引:7,自引:0,他引:7  
报道了采自陕西彬县地区中侏罗世延安组的孢粉化石60属,83种。经研究表明,陕西彬县地区延安组的孢粉组合是以裸子植物花粉为主,蕨类植物孢子次之。银杏、苏铁类和松柏类花粉在组合中占优势;桫椤科孢子在蕨类中具有较高的含量。根据孢粉组合特征及其对比,延安组的时代应属中侏罗世早期。陕西彬县地区当时的植被是以银杏、苏铁类和松柏类等乔木为主,并伴有桫椤科为主体的树蕨植物及草本植物,古气候应属大陆性亚热带气候。  相似文献   

17.
准噶尔盆地东北缘孔雀坪剖面金沟组孢粉组合中Protohaploxypinus,Striatoabieites等具肋双气囊花粉非常发育,类型丰富,达7属32种之多;Cordaitina,Zonalasporites等单气囊花粉分异度较高,但含量较低;少量出现单沟花粉、具肋纹花粉、无肋双气囊花粉和蕨类植物孢子等。所见孢粉类型中约1/2的已知种在新疆北部只见于二叠纪地层中,1/3已知种在晚石炭世至二叠纪地层中均可见到。孢粉组合特征与盆地南缘下二叠统塔什库拉组上部组合相似,地质时代为早二叠世空谷期。  相似文献   

18.
The paleontological history of Nypa, known today as the mangrovepalm, is traced through geological time back to the Late Cretaceous. Emphasis is laid on the New World occurrences, especially in NorthAmerica, where Nypa is known from fossil fruits and pollen. In SouthAmerica, the stratigraphic range of this palm extends from theMaastrichtian to the late Eocene, whereas in North America, Nypa isrestricted to only the Eocene. Nypa occurs as pollen all along theAmerican Gulf Coast from the early Eocene (Ypresian) to the late Eocene(Priabonian), while fruit records come from the early and middle Eoceneof Maryland and Texas, respectively. The floristics of these Eocenemangroves, including possible mangrove associates, and the developmentof mangrove vegetation in the neotropics through the Tertiary andQuaternary, are discussed. New paleobotanical evidence from a middleEocene faunal and floral assemblage in Texas, the Casa Blanca flora (LaredoFormation, Claiborne Group), which contains fossil Nypa pollen andfruits, is described in detail.  相似文献   

19.
The general morphology, surface sculpturing, and exine ultrastructure have been studied in dispersed monosulcate pollen from the Early Cretaceous of Transbaikalia, Russia. The pollen grains dominate the palynological assemblage extracted from coal deposits of the Khilok Formation in the Buryat Republic, which also contain ginkgoalean leaves of Baierella averianovii as the only constituent of the assemblage of plant megafossils. The relationship between the pollen grains and ginkgoalean leaves from this autochthonous burial is hypothesised on the basis of taphonomical analysis and palaeobiogeographical data. It is shown that the ectexine of the pollen grains includes a thick solid tectum, a thin granular infratectum and a thin foot layer; the endexine is fine-grained, slightly more electron-dense than the ectexine, and is preserved only in places. The distal aperture is formed by a thinning of the exine. No analogous ultrastructure has been described so far in fossil pollen grains of this morphotype studied ultrastructurally from in situ material. For comparison, we also studied the exine ultrastructure of pollen grains Ginkgo biloba. The fossil pollen is not identical to pollen of extant G. biloba, but shows several significant similarities in the exine ultrastructure, which does not contradict the presumable ginkgoalean affinity of the fossil pollen.  相似文献   

20.
新疆塔里木盆地侏罗系分布广泛,在库车凹陷和塔西南区发育最好。目前对库车凹陷的三叠纪和侏罗纪孢粉植物群研究较为深入,而对塔西南区侏罗纪孢粉化石专题研究不多,尚未建立孢粉组合。作者基于塔西南区乌恰中侏罗统塔尔尕组发现的孢子花粉33属48种的研究,建立了塔尔尕组孢粉组合。该组合以掌鳞杉科花粉Classopollis的优势和真蕨目桫椤科孢子Cyathidites的繁盛为特征,并含有丰富多样且颇具侏罗纪色彩的孢子花粉化石类型。该组合与西欧和俄罗斯巴柔期至巴通期孢粉组合以及北美和澳大利亚巴柔期至卡洛夫期孢粉组合可以进行对比;与我国新疆库车恰克马克组、陕西延安直罗组和湖北兴山沙溪庙组等孢粉组合也可对比。根据孢粉学证据,塔尔尕组的时代应属于中侏罗世晚期(巴通期至卡洛夫期)。当前孢粉植物群支持我国侏罗纪南北植物地理区系之西端分界之划分方案,即塔西南乌恰处于界线以南,而库车处于分界以北。  相似文献   

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