Preliminary palaeobotanical notes on the Early Cretaceous Cintura Formation (Sonora,Mexico)

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.     

Age determination of the Arcillas de Morella Formation (Maestrazgo Basin,Spain)

New palynological analysis of the Arcillas de Morella Formation provides data for determinations of age of the Lower Cretaceous strata in the Ermita Sant Antoni de la Vespa section located in the district of Els Ports in the Morella sub-basin of Castellón province, north-eastern Spain. Controversy still exists over the age of this formation, which is imprecisely dated as either Barremian or Aptian in age. Detailed reconnaissance of palynological content (dinocyst, pollen and spore assemblages) together with ammonoid data permits a more accurate biostratigraphic assessment of this deposit. The presence of Subtilisphaera terrula, Florentinia mantelli and Oligosphaeridium abaculum indicates a Barremian age at the base of the formation. The presence of Stellatopollis at the top of this formation possibly indicates that the deposit may be as old as latest Barremian. Furthermore, a recent study of ammonoids situated the Barremian-Aptian boundary within the overlying Cap de Vinyet Member of the Forcall Formation in the Morella sub-basin. This study together with the palynological assemblage from the Arcillas de Morella Formation indicates a Barremian age for this deposit.     

Paleobotanical remains from the Paleocene–lower Eocene Vagadkhol Formation, western India and their paleoclimatic and phytogeographic implications

A small assemblage of macro- and micro floral remains comprising fossil leaf impressions, silicified wood, spores, and pollen grains is reported from the Paleocene–lower Eocene Vagadkhol Formation (=Olpad Formation) exposed around Vagadkhol village in the Bharuch District of Gujarat, western India. The fossil leaves are represented by five genera and six species, namely, Polyalthia palaeosimiarum (Annonaceae), Acronychia siwalica (Rutaceae), Terminalia palaeocatapa and T. panandhroensis (Combretaceae), Lagerstroemia patelii (Lythraceae), and a new species, Gardenia vagadkholia (Rubiaceae). The lone fossil wood has been attributed to a new species, Schleicheroxylon bharuchense (Sapindaceae). The palynological assemblage, consisting of pollen grains and spores, comprises eleven taxa with more or less equal representation of pteridophytes, gymnosperms, and angiosperms. Angiospermous pollen grains include a new species Palmidites magnus. Spores are mostly pteridophytic but some fungal spores were also recovered. All the fossil species have been identified in the extant genera. The present day distribution of modern taxa comparable to the fossil assemblage recorded from the Vagadkhol area mostly indicate terrestrial lowland environment. Low frequency of pollen of two highland temperate taxa (Pinaceae) in the assemblage suggests that they may have been transported from a distant source. The wood and leaf taxa in the fossil assemblage are suggestive of tropical moist or wet forest with some deciduousness during the Paleocene–early Eocene. The presence of many fungal taxa further suggests the prevalence of enough humidity at the time of sedimentation.     

Exine ultrastructure in pollen grains of <Emphasis Type="Italic">Classopollis</Emphasis> Pflug from the Cretaceous of Lebanon

Pollen grains of Classopollis Pflug from the Cretaceous deposits of Lebanon were studied by means of light and electron microscopy. Ultrastructurally, they are similar to pollen grains, extracted from Classostrobus comptonensis Alvin, Spicer et Watson from the Barremian of England. The differences concern the shape and size of spinules, ultrastructure of apertural regions, and preservation of the endexine. An analysis of our data and published results revealed three types of infratectum existed in members of Circumpolles: (1) with branchy elements, (2) with columella-like non-branching elements, and (3) with large granules arranged in one row. The palynological assemblage is described in detail; problems of dating are discussed.     

Palynological investigation in the lower jurassic of the vicentinian alps (Northeastern Italy)

The present paper emphasizes the applicability of palynological data as an aid to the solution of the problems related to the correlation of non-ammonitiferous Liassic strata in the Southern Alps with the ammonoid-based standard stages as recognized in the outer-Alpine part of Europe.In the Noriglio Grey Limestone Formation of the Vicentinian Alps, northeastern Italy, rich and well-preserved Liassic palynological assemblages can be abundantly found in the marly intercalations of its upper part; in the lower part palynological assemblages have appeared to be very rare. A qualitative and quantitative analysis of the assemblages has indicated the presence of a single palynological assemblage zone. Minor compositional differences do not warrant a zonal subdivision.The overall composition of the assemblages is characterized by the general dominance of Circulina and smooth trilete spores in combination with a large amount of relatively rarely occurring forms of spores, pollen grains and other acid-resistant microfossils.Because of the presence of rich and well-preserved material, it has been possible to detect a relatively wide range of variability within species of Tigrisporites, Foveosporites, Porcellispora and Crassosphaera.Among the forms which could not be matched with previously described taxa the new formgenus Skarbysporites is formally erected together with the new species Skarbysporites elsendoornii, Skarbysporites puntii, Foveosporites visscheri and Tigrisporites jonkeri. Moreover, an emended diagnosis of Circulina is proposed, implicating the assignment to this formgenus of most forms generally included in Classo pollis. Also the generic diagnosis of Tigrisporites is emended.An evaluation of the Liassic palynological assemblages from the outer-Alpine part of Europe with special reference to their potential in characterizing the ammonoid-based chronostratigraphical subdivisions may indicate that two temporal subdivisions of the Liassic Series on the basis of palynological characteristics are now slowly becoming discernable: an assemblage zone characterizing the Hettangian, Sinemurian and Lower Pliensbachian, and an assemblage zone characterizing the Upper Pliensbachian and Toarcian.Because of the possibility of a correlation with the latter zone, the assemblages from the Noriglio Grey Limestone Formation can be reasonably regarded to be indicative of a Late Pliensbachian—Toarchian age of the source-strata.When considering the ammonoid evidence from the overlying “Cape San Vigilio Oolite” it may be concluded that the upper part of the lower subdivision of the Noriglio Grey Limestone Formation and the Rotzo Member represent the Upper Pliensbachian—Lower Toarcian.Because of its potential in correlating non-ammonitiferous strata from the Southern Alps with the successions in northwestern Europe, it is believed that palynology may earn a prominent place in regional Liassic chronostratigraphy.     

Some evidence for infrageneric classification in Ziziphora L. (Lamiaceae:Mentheae)

The genus Ziziphora L. (Lamiaceae) consists of annual herbs, except Ziziphora clinopodioides, and is represented by six taxa in the flora of Turkey: Z. clinopodioides, Z. capitata, Z. persica, Z. tenuior, Z. taurica subsp. taurica and Z. taurica subsp. cleonioides. They are strong aromatic herbs and important medicinal plants. This study has been conducted to determine the palynological and karyological features of these taxa. The pollen morphology and exine structure of Ziziphora species were investigated by light microscope and scanning electron microscope. Pollen grains were determined as hexacolpate, medium in size and a circular or elliptic amb. The shape of pollen grains varies from oblate to prolate spheroidal. Ornamentation types of pollen grains are bireticulate, microreticulate or perforate. Somatic chromosome number has been determined and counted as 2n = 16, 18. Results indicate that the pollen characters and chromosome numbers of the genus are valuable for taxonomic applications and may be useful for infrageneric classification.     

The ultrastructure of fossil dispersed monosulcate pollen from the Early Cretaceous of Transbaikalia,Russia

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.     

Late Carboniferous palynostratigraphy of the Itararé Subgroup, northeastern Paraná Basin, Brazil

A new biozonation is proposed for the Late Carboniferous strata of the northeastern Paraná Basin (São Paulo and Paraná States), based on well-preserved palynological assemblages recovered from outcrops and core samples retrieved from the Itararé Subgroup. Assemblages include forty-nine species of trilete spores and twenty-five pollen species. The oldest biozone, the Ahrensisporites cristatus Interval Zone (AcZ), in the basal portion of the Itararé Subgroup, includes eleven exclusive spore species, and is assigned a Pennsylvanian (late Bashkirian to Kasimovian) age. The overlying proposed biozone, the Crucisaccites monoletus Interval Zone (CmZ), dated late Pennsylvanian (Kasimovian to Gzhelian), ranges approximately from the top of the lower portion to the middle portion of the Itararé Subgroup, bears only one exclusive species of pollen. Both zones are characterized by the dominance of trilete spores and monosaccate pollen grains, including also few taeniate pollen grains. Furthermore, the basal Protohaploxypinus goraiensis Subzone of the Vittatina costabilis Interval Zone (VcZ) is broadly recognized for the first time in the upper portion of the Itararé Subgroup in the northeastern Paraná Basin. This subzone is attributed to the Early Permian (Early Cisuralian), and is characterized by the dominance of monosaccate pollen grains, a significant increase of taeniate grains (mainly Protohaploxypinus spp.), apart from the appearance of polyplicate pollen (Vittatina spp.). Reference sections and the main characteristics of the two new zones (AcZ and CmZ) are presented, along with a preliminary palynological correlation and discussion on their ages.     

辽河盆地大民屯凹陷沈249井早白垩世九佛堂组孢粉组合

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。     

Floral data from the mid-Cenozoic of central Pakistan

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.     

A new species of <Emphasis Type="Italic">Baierella</Emphasis> from the Krasnyi Yar locality,Early Cretaceous of western Transbaikalia

Plant remains of Baierella R. Potonié (Ginkgoales) were found for the first time in the Lower Cretaceous deposits of the Khilok Formation (Buryatia Republic), where they form a thin coal bed. A new species, B. averianovii, is described from the Krasnyi Yar locality. The monodominant burial of the new species in combination with pollen grains of Ginkgocycadophytus prevailing in the relevant palynological assemblage allows the authors to reconstruct a monospecific woody wetland plant community.     

Le bassin permien de Guardia Pisano (Sud-Ouest de la Sardaigne, Italie) : palynostratigraphie, paléophytogéographie, corrélations et âge radiométrique des produits volcaniques associés

The Permian section outcropping at Guardia Pisano (Sulcis area, SW Sardinia), comprises two successions, separated by an unconformity. The lower succession is composed of grey-black sandy shales, rich in plant remains and in sporomorphs, deposited in a fluvial-lacustrine to palustrine environment; followed by layers of rhyolithic lavas and volcanoclastites with silicified plant trunks. Most of the analysed samples yielded a profusion of pollen and spores in a very good state of preservation. Three associations were distinguished. The first one comprises mostly radial and bilateral monosaccate pollen grains and very few spores. This association is characterized by the presence of pollen grains of the genera Crucisaccites, Luberisaccites, Gondwanopollis and Lueckisporites, together with very abundant Potonieisporites and subordinate Florinites. The second association comprises mostly pollen grains of the genus Potonieisporites, represented by many species, together with Limitisporites, Costapollenites, Vittatina and others. Spores mainly represented by azonate trilete and monolete types are more frequent than in the previous association. These first two palynological associations reflect assemblages of meso-xerophilous plants growing in dryer environments, belonging to tropical and subtropical phytogeographic biomas. The third association, mainly composed of Sphenophyte spores, is autochthonous and corresponds to a swampy hygrophilous flora settled after the filling up of the basin. The age inferred by means of sporomorphs is early Asselian which is in good agreement with the mean radiometric age of the volcanic rocks obtained by the ‘SHRIMP’ and the lead-zircon evaporation methods (297 ± 5 Ma). The upper succession, is composed of grey to red sandstones and thin pelites deposited on an alluvial plain under very hot and humid climate; its Permian, post-Asselian age cannot be better constrained because of the scarcity of the fossil content.     

Pollen morphology and its taxonomic significance of the monotropoideae (Ericaceae)

A palynological survey, including LM, SEM and TEM is presented for eight genera, nine species and 76 samples of the Monotropoideae which is composed of 10 genera and 13 species. On the basis of the aperture number and shape, the following six pollen types are recognized: 1) 3-colp(oroid) ate—Allotropa, 2) 2-colpor(oid)ate—Monotropsis andHemitomes, 3) 4-colpor(oid)ate—Pterospora, Sarcodes andPleuricospora, 4) 2- and 3-colpor(oid)ate—Monotropa hypopitys, 5) 3-colporate and-porate —Monotropa uniflora, 6) 3- to 4- porate—Monotropastrum humile. Relationships among taxa within the Monotropoideae are illustrated on the palynological characters including the aperture type, exine sculpture and structure. Both pollen grains with two and four apertures have evolved independently from pollen grains with three apertures, according to the infraspecific variation of aperture numbers and the usual occurrence of three-aperturate pollen grains in the Ericaceae. 3-colp(oroid)ate pollen ofAllotropa is the most primitive and occupies an isolated position in the subfamily, on the other hand 3- to 4-porate pollen ofMonotropastrum humile is most advanced in the subfamily, probably even in the Ericaceae. A reduced sexine inMonotropastrum humile appears to be a specialized pollen character. Infraspecific geographical difference in palynological characters is revealed in two species ofMonotropa for the first time.M. hypopitys is basically characterized by pollen grains with two apertures in the New World vs. three apertures in the Old World.M. uniflora is basically characterized by 3-porate pollen in the New World vs. 3-colporate in the Old World. In both species pollen grains with more primitive characters usually occur in the Old World.     

Fossil floral structures of a basal angiosperm with monocolpate,reticulate-acolumellate pollen from the Early Cretaceous of Portugal

Distinctive monocolpate and reticulate-acolumellate pollen grains with a coarse, loosely attached reticulum have long been known as a conspicuous element of many palynological assemblages from the Early and mid-Cretaceous. These grains are now described in situ in staminate structures and on the surface of pistillate organs from two Early Cretaceous (Barremian or Aptian) mesofloras from Portugal (Vale de Agua and Buarcos). Staminate organs include a staminate axis with spirally arranged stamens and many isolated stamens. Stamens consist of a short filament, a dithecate, tetrasporangiate anther, and a short apical extension of the connective. Anther dehiscence is extrorse by longitudinal slits and in situ pollen is monocolpate, semi-tectate with a coarse, loosely attached reticulum composed of narrow muri with a spiny ornamentation. The infratectal layer of the pollen wall is thin, granular, and lacking columellae; and the foot layer is distinct. The endexine is thin, except under the aperture where it is thick. The pistillate organs are minute consisting of a simple unilocular ovary containing a single thin-walled seed. Associated with staminate and pistillate structures are many coprolites consisting almost exclusively of pollen grains of this distinctive type. The staminate and pistillate organs are not found in organic connection, and two new genera are established to accommodate the new floral structures: Pennistemon comprising the staminate structures and Pennicarpus comprising the pistillate structures. A new genus, Pennipollis, is also established for the dispersed grains, based on the type species Peromonolites peroreticulatus Brenner, since no appropriate genus has yet been described for these acolumellate grains. Features of the pollen grains strongly indicate affinity with members of the Alismatales and characters of the mesofossils also support this assignment. This is the first record of putative monocots in the early Cretaceous based on combined pollen and floral features.     

新疆塔里木拜城地区早白垩世舒善河组孢粉组合

基于新疆塔里木盆地北部拜城卡普沙良河剖面下白垩统舒善河组发现的29属48种孢子花粉的研究,建立舒善河组自下而上的4个孢粉亚组合,分别为Classopollis-Cycadopites-Lygodioisporites-Biretisporites(CCLB)亚组合,Classopollis-Dicheiropollis-Schizaeoisporites-Klukisporites(CDSK)亚组合,Classopollis-Dicheiropollis-Par-visaccites-Lygodiumsporites(CDPL)亚组合和Classopollis-Dicheiropollis-Pinuspollenites-Impardecispora(CDPI)亚组合。舒善河组孢粉植物群以松柏类掌鳞杉科植物占优势以及真蕨类海金沙科的繁盛为主要特征。该孢粉植物群与欧洲、亚洲、美洲和澳大利亚早白垩世尼欧克姆期孢粉植物群可以对比。根据孢粉学证据,舒善河组的时代属于尼欧克姆期或欧特里夫期至巴列姆期。     

Palynofloras from the upper Barremian-Aptian Nishihiro Formation (Outer Zone of southwest Japan) and the appearance of angiosperms in Japan

Palynomorphs are reported for the first time from the Nishihiro Formation (Wakayama Prefecture, Outer Zone of southwest Japan). The Nishihiro Formation consists of brackish to shallow marine deposits, dated as late Barremian to Aptian from geological correlations. Spores prevail in the assemblage, representing Filicopsida (mainly Cyatheaceae and Anemiaceae), Marchantiopsida and Lycopsida. The pollen assemblage is dominated by Coniferales, whereas Gnetales and Bennettitales/Cycadales are only rarely observed. Moreover, we report angiosperm pollen grains of the genus Retimonocolpites for the first time in the Early Cretaceous sediments of Japan. Pollen grains of the Retimonocolpites Group are typical of early angiosperms and commonly found in assemblages from the early to mid-Cretaceous of all paleofloristic provinces. Until this paper, the oldest angiosperm fossils in Japan were represented by a single seed and a wood reported from the Albian of Hokkaido. The oldest reliable angiosperm pollen grains were reported in Hokkaido from the Cenomanian, and in Honshu from the Coniacian. Thus, Retimonocolpites pollen grains reported in the present study represent the oldest record of angiosperms in Japan. They indicate an appearance of the angiosperms in Japan older than thought until now, which is consistent with that proposed elsewhere in eastern Asia.     

Reconstructing Earth's Past Climates: The Hidden Secrets of Pollen

Palynology is the study of fossil pollen and spores, and these tiny grains can provide fundamental information about past climates on Earth. Among their many unique and useful properties, pollen and spores are composed of some of the most chemically resistant organic compounds found in nature. They are also produced in vast quantities and are unique to the specific plant from which they originate. All these features make them ideal to reconstruct past climates from both recent history as well as from the ancient past. The purpose of this activity is to get students familiar with palynology and how scientists study climate change. It is based on real palynological data acquired from Antarctic cores obtained recently from the ANDRILL and SHALDRIL drilling campaigns. In order for students to understand this research and its importance, they will separate and identify pollen and spores from a simulated core sample in which different species of plants are represented as different colors of glitter. Students will compare the types and abundance of pollen and spores found in each layer of the core sample and research the climate preferences of the types of plants recovered in order to reconstruct the past climates of Antarctica.     

Pollen grain morphology ofCoris (Primulaceae)

Pollen grain morphology, sculpturing, and wall ultrastructure are investigated in two species ofCoris (Primulaceae),C. monspeliensis L. andC. hispanica Lange. The study includes both acetolysed and unacetolysed pollen. No evidence of any major palynological difference is recorded between these two species, apart from a somewhat larger pollen inC. monspeliensis. However,Coris can be distinguished from the remaining members of thePrimulaceae by the conjunction of relatively large pollen grains, prominent margo, and particular tectal pattern causing a reticulate surface with minute luminal perforations decreasing towards the colpi. From both these distinctive features, and others typically primulaceous, some evolutionary considerations are inferred. Finally, the higher proportion of irregular grains inC. hispanica is interpreted in light of environmental stress.     

青海柴达木盆地鄂博梁2号井早侏罗世孢粉植物群及其地层意义

本文系统研究了产自青海柴达木盆地鄂博梁2号井4501-4852．7m层段中的孢粉化石,共计55属96种,其中蕨类植物孢子25属45种,裸子植物花粉28属49种,疑源类2属2种。组成以Cyathidites-Deltoidospora-Piceites-Quadraeculina-Classopollis为特征的孢粉组合。根据组合内一些重要分子的地质时限讨论及与有关孢粉组合的对比,其时代应归为早侏罗世晚期。     

Fossil spores and pollen grains of cretaceous (Upper campanian) from Sakhalin, Russia

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).