bluuebunny/crossref_metadata_2025 huggingface dataset:
Kashmiropteris meyenii Kapoor: A possible cycadale'an leaf from the Early Permian Mamal Formation in the Kashmir Himalaya
Authors: Kapoor H.M. , Bajpai Usha , Maheshwari H.K.
Published: September 2022

The nomenclatural status of Kashmiropteris meyenii gen. et sp. nov. proposed by Kapoor is formalised. On the basis of gross morphological features it is suggested that the taxon may have cycadalean affinities.
Record of Early Tertiary palynotaxa from Siang District, Arunachal Pradesh, India
Authors: Tripathi S.K.M. , Singh Trilochan
Published: September 2022

Palynotaxa, viz., Ctenolophonidites, Lakiapollis, Tricolporopollis, Pellicieroipollis and Incrotonipollis, have been recovered from the sediments exposed near Rengging along the Siang River, on Yinkiyong-Gobuik road, and near Dalbing in the Yamne Valley in Siang District, Arunachal Pradesh. Recovery of these palynotaxa provides additional evidence for the occurrence of Early Tertiary sediments in Arunachal foot-hills and Lesser Himalaya.
Palynology of the Mesozoic sediments exposed near Ellichpur, Maharashtra
Authors: Kumar Pramod
Published: September 2022

The paper records palynofossils from the dark grey shales/clays (inliers) exposed at Belkher Village, north of Ellichpur town in Maharashtra. The assemblage contains 41 species assigned to 22 genera and is characterised by pteridophytic and bryophytic components, viz., Callispora potoniei, Contignisporites glebulentus, Murospora, Triporoletes reticulatus, Coptospora kutchensis, Cooksonites cf. C. rajmahalensis, etc. The prominence of Callialasporites followed by Podocarpidites, Alisporites and Araucariacites is noteworthy. The assemblage is comparable to the palynozones-D of Rajmahal Hills, the assemblage recovered from Sivaganga area of Cauvery Basin, and Dharesi nala section of Bhuj Formation, Kutch Basin, which are assigned a Neocomian-Aptian age. The presence of spore-pollen, algal or fungal entities suggests freshwater conditions during deposition.
Palaeobiology of Vindhyan
Authors: Maithy P.K.
Published: September 2022

Biological remains and their activities, preserved in the form of ichnofossils and organosedimentary structures in the Vindhyan sediments are critically reviewed. The diversification of metaphytes and metazoans and their significance in biostratigraphy have also been discussed.
Alien elements in the Gondwana Flora of India
Authors: Srivastava A.K.
Published: September 2022

The occurrence of northern hemispheric taxa in Gondwana is considered as alien to the Glossopteris and Dicroidium floras of the Southern Hemisphere. The morphology, evolutionary lineages, and stratigraphic distribution of Euramerian, Cathaysian and Angaran forms in the Gondwana flora of India are examined in view of their latest discoveries in the Permian and Triassic sequences. The study indicates that some of the elements of contemporaneous floras possess characteristic affiliation with the Gondwana flora, likewise, some of the Gondwana elements exemplify the comparative characters of northern forms. Possible linkages, association, existence and ancestry of the Gondwana flora vis a vis Northern floras are discussed.
Morpho-evolutionary biohorizon stratigraphy and cladistics in saccate pollen through Gondwana Sequence of India
Authors: Vijaya  , Tiwari R.S.
Published: September 2022

The morphographic characters of fossil saccate pollen and their evolutionary sequence through the span of Gondwana formations play a vital role in the biohorizon stratigraphy. Based on evolutionary changes in the morphology of the pollen group, their FADs (First Appearance Datums) and LADs (Last Appearance Datum) and the cluster levels, eleven biohorizons and ten inter-biohorizon Zones (Interval-zones) have been identified. The model of alliance among the prime morphographies has been acquired through simple character state analysis. By extrapolation of lineages, four unique monosaccate and one simple disaccate organizations could be identified to have their origin in the early Upper Carboniferous stock of Australia, which, in turn, were related with the Devonian progymnospermopsida complex. The five outgroup stocks continued as such into the late Early Asselian Talchir Formation of India and sprouted in the subsequent Permian time. A gap in the sequence has been identified during Upper Carboniferous of Australia and the lowermost Permian in India. The sixth major lineage of striate pollen branched off from the simple disaccate pollen lineage to appear in the Late Asselian. Cladistic analysis supports the applicability of the proposed biohorizons as important stratigraphic parameter. The congruence of derived and ancestral states of internally compatible and persimonically harmonious characters in pollen organizations has been used in drawing relationship trees. Thus, the cladograms and stralograms (nested diagrams of stratigraphic occurrences) together depict the maximum diversification at the lower Upper Talchir and the P/Tr boundary. The major extinction of monosaccates at the Lower Permian-Upper Permian boundary and that of the striate-disaccates in the basal Triassic have also been brought to light. The reasons of such a behaviour is attributed to environmental stresses caused by massive glaciations during Early Permian Talchir Formation, climatic changes towards warmer-drier situation at Lower/Upper Permian passage and global cooling and regression at the permo-Triassic level. Pollen features, like striations, taeniae, girdling monosaccus, clefts and remnant of germinal marks, etc. of the Permian and Triassic have perished completely by the end of Triassic. Most of the Jurassic palyno-assemblages contain the fag-end organizations of simple disaccate lineages; the experimentation seems to have attained a more simple state in the morphography of saccate pollen which continued thereafter.
Permian palynological assemblages in the Godavari Graben
Authors: Srivastava S.C.
Published: September 2022

Palynological investigations carried out in the Godavari Graben during the last three decades have led to suggest the existence of nine palynozones from the Talchir to Kamthi formations. The Talchir Formation palynological assemblage, though dominated by the presence of radial monosaccate pollen grains, exhibits evidences of fluvio-glacial and lacustrine environment of deposition alongwith periodical influence of marine incursions. The presence of Karharbari and Barren Measures (Kulti) as distinct formations has been substantiated with palynological data. The occurrence of Corisaccites-Guttulapollenites palynozone and Densipollenites palynozone in the Middle Member of the Kamthi Formation represents the uppermost Permian palynoflora in Godavari Graben.
Evolutionary reproductive biologies in the Mesozoic plants of India
Authors: Sukh-Dev
Published: September 2022

The reproductive biologies in the Mesozoic plants are dealt with taking into consideration form and function of the reproductive organs. The Mesozoic flora inherited homospory, heterospory, pollen and seed formation from their Palaeozoic ancestors. Most of the Palaeozoic forms vanished by the close of Permian due to change of environment. The Triassic Period nursed the leftovers from the Permian as well as put forth new elements like Lepidopteris, Dicroidium and allied genera of Peltaspermaceae, Corystospermaceae and members of Caytoniaceae in which the seeds were protected in cupules. Thus the development of cupule in these genera changed the course of plant evolution. Later, with the amelioration of climate the cycads grew to prominence with exposed seeds, and subsequently they were overtaken by the rise of more advanced conifers. Meanwhile this flora also produced 'flower-like' structures in the cycadeoides and 'fruit-like' structures in Caytoniales and Pentoxyleae by providing fleshy growth around the seeds. The hot, arid conditions again reoccurred towards the close of the Early Cretaceous. At this time the angiosperms appeared with enclosed seeds, heralding another change in the course of plant evolution.
Cenozoic plant fossils and the Himalayan orogeny
Authors: Singh H.P.
Published: September 2022

Selected palyno- and megafloras from the Cenozoic Era of extrapeninsular India have been examined in the orogenic context of the Himalaya. Distribution of vegetations and variation in climates are in conformity with the periodic phases of the Himalayan uplift. Continued rise of the Himalaya acted as a barrier for the flow of moisture resulting in lesser precipitation, higher snow cover and increased aridity. In response to the topographical and climatic variations a progressive change occurred in the composition of vegetations during the past 60 Ma. The ancestral tropical floras inhabited the lower slopes, whereas the temperate floras colonized the higher slopes. Altitudinal segregation of floras is clearly evident from the Mid-Miocene orogeny. Palaeocene to Mid-Pleistocene plant diversity generally varies from evergreen, semi-evergreen, dry/moist deciduous, warm temperate to temperate forest types. Migrations/immigrations and extinctions of plant taxa were largely influenced by physiographical and climatic changes. Enrichment and diversification of the Neogene Himalayan floras have also been brought in through the process of evolution. Cult-historical evidences point out that the Himalayan range continued to rise even after the advent of man.
Stratigraphical implications of Tertiary palynological succession in north-eastern and western India
Authors: Kar R.K.
Published: September 2022

Cretaceous and Tertiary sedimentary rocks are found overlying a Precambrian granite basement or occasionally the Sylhet Trap (Late Jurassic) in north-east India whereas in Kutch, western India, the Tertiary rocks rest on the Deccan Trap and its derivatives. In north-east the Tertiary succession is almost complete whereas in Kutch the Early and Middle Palaeocene and Late Eocene sediments are missing. More than 150 spores and pollen genera' are described from the Tertiary sediments but except about 20 all are long ranging. The Early Tertiary palynological succession in north-east and Kutch is more or less similar and all the marker taxa are found simultaneously in the equivalent formations in both the regions. In north-east India, throughout the Tertiary succession, the pteridophytic spores are found in abundance whereas in Kutch they are found in meagre percentage. The distribution of marker taxa throughout the Tertiary has been shown with the help of a chart. It is assumed that during Palaeocene to Eocene the plants grew in tropical, coastal swamps whereas from Oligocene onwards the deposition was mostly riverine in the eastern region.
Recent advances in studies on fossil Charophyta
Authors: Bhatia S.B.
Published: September 2022

The main objective of the paper is to give a synoptic review of the more recent works on fossil Charophyta from India, particularly of those that have been published since the last review entitled “Post-Palaeozoic fossil charophyta of India” published in 1982 (Bhatia, 1982). The study of fossil Charophyta in India has remained largely neglected since the first fossil gyrogonite, Chara malcolmsoni, was described (Sowerby, 1839). It is only during the last two decades that the study of fossil charophytes has received a sudden impetus. Although, there is no record of Palaeozoic charophytes from India, the Mesozoic and Cenozoic charophytes are now much better documented.
Fossil dinoflagellates: an emerging tool in Indian biostratigraphy
Authors: Jain K.P. , Garg R. , Khowaja-Ateequzzaman
Published: September 2022

The total span of fossil dinoflagellate research in India stretches within the last three decades. Two distinct phases of this study are recognised, the phase of Reconnaissance and Understanding (1961-70) and the phase of Establishment and Refinement (1971-1990). The significance of dinoflagellate cysts in resolving various biostratigraphic problems of Mesozoic and Cenozoic sedimentary sequences is discussed citing specific examples from Indian basins. Recent approaches towards achieving biostratigraphic precision through integration with smaller planktonic and larger benthonic foraminifera, ammonites, and calcareous nannoplankton, are specifically highlighted focusing the potential of dinoflagellate cysts to resolve the time boundaries. A review of the previous literature has revealed that wrong identifications, especially of marker taxa, have led to major errors in age determination of sedimentary sequences. A few cases are exemplified. An appeal has been made to fellow palynologists to be careful in presenting geological and palynological data to maintain the viability and potential of this group of microfossils in biostratigraphy.
Fossil diatoms and their significance
Authors: Chandra Anil
Published: September 2022

A brief introduction to diatoms, an important group of siliceous organisms, is presented. This includes the history of diatom study, their classification and morphology, cell structure, ecology, nutrition and reproduction, palaeogeography and evolutionary history. Association of diatoms with volcanism and silica dissolution and overgrowth of fossil diatoms are also provided. The significance of fossil diatoms in palaeoecology and biostratigraphy including palaeoceanography is highlighted. Fossil diatoms known from India and a few DSDP sites of the Indian Ocean are listed along with their geological horizon. In India, reports of marine and freshwater diatoms were made from the Miocene rocks of Nancowry Island (Ehrenberg, 1851) and from the Karewa Formation of Kashmir (Lundquist, 1936), respectively.
Temporal and spatial variations of the type and rank of Gondwana coals of India
Authors: Navale G.K.B.
Published: September 2022

Gondwana coals associated with Permian sediments in peninsular India vary widely but there is a distinct tendency of variation to be diagnostic both in time and space. The three maceral groups (Vitrinite, Liptinite and Inertinite) which are derived from diversified plant material exist in the Gondwana coals. However, maceral composition is controlled by the type of plant material available for accumulation as peat and by Eh and pH of the ancient swamp. These may all be in part controlled by the period when the peat was formed, climate and sedimentary environment. These variables seem to be inter-related rather than independent. The coals that occur in Karharbari, Barakar and Raniganj formations differ significantly in their nature and relative distribution of coal constituents.

The coals, deposited under wide range of tectonosedimentary settings of Permian Gondwana sequence, reveal fusic, trimaceric and vitric coal types and by and large associated with different lithologic sequences in ascending order. Provincialism can be discerned both in relation to lateral variation of individual seams and in differences between the modal composition found in different coal measures. Significant variation occurs within the individual seams, however, they retain some degree of characteristic petrological identity. Different seams in a given stratigraphic unit may differ widely in their petrographic composition but are characterized by their diagnostic modal composition. The coals of Damodar, Son-Mahanadi, Pench-Kanhan and Wardha-Godavari basins provide good examples for the temporal and spatial variation of the coal seams.

Coal rank assessed has shown significant variation in rank both in space and time ranging from high volatile sub-bituminous to low volatile bituminous stages including coking coal types. The wide range of coal rank recognized in the Gondwana of India is controlled by geothermal gradients and tectonic features. These have affected the extent of coalification by controlling the heat flow to which coals have been exposed. Tectonism may also have exercised some control over coal types (rank types) but only as a part of a complex mechanism which also involved sedimentary environment, the climate and the flora at any given time.
Symposium on Evolutionary Plant Biology-an introduction to the theme
Authors: Venkatachala B.S.
Published: September 2022

NA
Prebiotic organic chemistry and the origin of life
Authors: Bhakuni D.S.
Published: September 2022

Prebiotic synthesis of organic compounds such as amino, hydroxyl and aliphatic acids, urea, imidazoles and synthesis of amino acids, co-enzymes, nucleosides under primitive earth conditions have been reviewed.
The classification of early land plants-revisited
Authors: Banks Harlan P.
Published: September 2022

Three suprageneric categories applied to early land plants- Rhyniophytina, Zosterophyllophytina, Trimerophytina- proposed by Banks in 1968 are reviewed and found to have still some usefulness. Additions to each are noted, some deletions are made, and some early plants that display features of more than one category are set aside as Aberrant Genera.
The functional biology of Devonian spores with bifurcate processes-a hypothesis
Authors: Dilcher D.L. , Kar R.K. , Dettmann M.E.
Published: September 2022

Aquatic heterosporous ferns may have grapnel like glochidia, e.g., Azolla, specialized for anchoring a microspore mass to a megaspore. Thus, in an aquatic system, the free floating microspore mass (glochidia) and megaspore are held in close proximity when the sperm cells are released. Similar structures are known from the Cretaceous and Tertiary megaspores and microspores such as Azollopsis and Ariadnaesporites and are considered to have functioned in fertilization. This demonstrate that, as part of the evolution of the aquatic heterosporous habit in the ferns during the Cretaceous, functional and structural elements of the megaspores and microspores evolved early. A parallel evolution event can also be observed in the initial radiation of heterosporous plants during the Late Devonian. Megaspores and microspores, with probable lycopods affinities, demonstrate grapnel-like processes which we suggest were similar to the functional/structural elements known from the Cretaceous aquatic ferns. From this we conclude that many of the Middle and Late Devonian heterosporous plants were aquatic and that there were two parallel evolutionary events, one in the evolution of Devonian aquatic lycopods and a second in the evolution of Cretaceous aquatic ferns. Both of these evolutionary events are characterized by similar functional/structural elements in the megaspores and microspores.
Evolution of a cormophytic plant body in lower vascular plants
Authors: Nayer B.K.
Published: September 2022

Possession of a cormophytic plant body and stelar system distinguishes vascular plants from thallophytic ancestors. Based on morphology and development of sporophyte and gametophyte of pteridophytes it is argued that current interpretations of morphology and evolution of these features in terms of Axial theory and Stelar theory are untenable in these primitive vascular plants. The leaf, and not the axis/stem, is the primary organ and the first to evolve. The leaf along with its associated root constitutes a Phyllorhize which is the basic unit of construction of the plant body. Shoot apical meristem functions only in initiating leaves and branches and what appears as stem is a product of conjoined leaf bases, the shoot meristem contributing little to its construction. Vasculature is developed only in tissues derived from leaf and root meristems; no vasculature is developed in tissue derived from the shoot meristem. Stelar cylinder consists of secondarily interconnected basal regions of leaf vasculatures and sometimes also vasculature of leaf-associated roots. The pattern of growth (different in taxa having erect rhizome and plagiotropic rhizome) determines the nature of the stelar cylinder. Evolution apparently followed the same course in gametophytic and sporophytic generations, and evolution of pteridophyte gametophyte indicates that the primitive form was an amorphous cushion shaped thallus devoid of meristem and vasculature. It is shown how a phyllorhize unit evolved from such a plant body. Morphological, anatomical and ontogenetic evidences are presented in support of the contention that the pteridophyte plant body is formed of conjoined leaf bases and its stele is the product of leaf base vasculatures interconnected in a regular pattern. Also, it is shown that stelar evolution did not follow the sequence suggested by Stelar theory.
Phloem in Pinophyta
Authors: Paliwal G.S.
Published: September 2022

The gymnospermous phloem shows major differences from those of the cryptogams on one hand and the angiosperms on the other. These include both the type of conducting cells as well as the cellular composition. Even more important is the degree and nature of functional inter-relationship between the conducting and parenchyma cells. The following evolutionary trends have been suggested.

Increase in the amount of axial parenchyma;

Decrease in the number of albuminous cells in the rays;

Increase in the axial albuminous cells;

Increase in the fibres;

Increase in the regular arrangement of cells.

The work on the fossil taxa does provide variable support to these suggestions. It is generally believed that the cryptogamic sieve element arose from a parenchyma cell and all the phloem produced in the fossil lycopods, Sphenopsida and ferns is primary in origin. Here the phloem consists of either sieve elements only or the sieve elements with scattered parenchyma cells. There is no definite relationship between the conducting elements and the parenchyma cells as seen in the seed plants. Additional parenchyma is often present in the form of a sheath separating the xylem from the narrow phloem tissue.

The typical cryptogamic sieve elements are identical to the elongate parenchyma cells. These are relatively small in diameter, longer than the parenchyma cells but shorter than the gymnospermous sieve cells. In some taxa, the sieve elements are of two sizes: large (up to 600µm) and small (between 100-1500 µm). The end walls of the cryptogamous sieve elements are horizontal or slightly oblique and the sieve areas are small and vary markedly in their outline. The sieve pores occur in the sieve areas as well as scattered on the vertical walls. The callose deposition has been found in Psilotum, lycopods and the ferns.
DNA homology as a tool for determination of divergence of phanerogamic taxa
Authors: Sen S.P. , Roy D.G. Dutta
Published: September 2022

The utility of DNA homology as tool for determination of divergence of phanerogamic taxa is discussed. DNA-DNA hybridization values of living gymnosperms and members of primitive angiospermic families indicate highest homology between Gnetum and Magnoliaceae, supporting the gnetalean origin of angiosperms. Conifers like Thuja occidentalis show no less homology with primitive angiosperm families than do the cycads. The living monocots and gymnosperms have diverged even farther. The primitive dicotyledonous families revealed fairly high homology among themselves but the other more derived families have diverged appreciably. The DNA homology among the primitive dicots and monocots varied between 45 and 60 per cent. With respect to the more advanced families, the homology values decreased. Families at moderate levels of evolutionary advancement exhibit intermediate values when compared. The two major groups of angiosperms seem to have evolved along parallel lines from a common stock in the remote past.
Trends in the evolution of the angiosperm flowers
Authors: Rao R.R.
Published: September 2022

The flower is classically defined as a determinate shoot that bears modified leaves. It is believed that the primitive flowers are those which possess numerous floral parts, all spirally arranged on the floral axis. Discussing the origin of the flowers it is claimed that the flowering plants might have evolved from the hypothetical ‘Proangiosperms’ that existed in the Late Mesozoic Era and had characters of both gymnosperms and angiosperms. Among other factors, seasonal climate is believed to have caused the angiospermatization in the early proangisperms.

Primitive flowers, such as those of Magnoliales, are all solitary, regular and moderately sized in which the floral parts are all separate and indefinite in number. It is stressed that the evolution of the flower is guided by (a) principle of progressive economy in the production of floral parts, and (b) principle of progressive adaptation to insect visitors. Adaptations of angiosperms to insect visitors include development of conspicuous flowers (either by enlargement of individual flowers or by aggregation of separate flowers), development of zygomorphy and fusion of floral parts. Primitive flowers lack a differentiation between calyx and corolla. Derived perianth features are said to include (a) evolution of two distinct whorls of perianth-calyx and corolla, (b) establishment of a regular number of floral parts, (c) fusion of sepals and petals, and (d) development of zygomorphy.

Primitive stamens, characteristics of the genus Degeneria (Degeneriaceae: Magnoliidae) are broad and laminar and evolution proceeded towards transformation of such laminar stamens to a distinct filament and anther. Tendency towards reduction in the number of stamens is also quite evident. Similarly the flowers with many free carpels (as in Magnoliales) have given rise to flowers with syncarpous gynoecia which have further evolved to give rise to inferior ovary by the fusion of gynoecial walls to the calyx and receptacle.

Finally it is said that the above evolutionary modifications in the flowers/flower parts are fundamentally guided by the mode of pollination and pollination mechanism and have been attempted independently by different groups of plants- a fact that suggests the polyphyletic nature of angiosperms.
Miocene floristic change at 15 Ma, Nevada to Washington, U.S.A.
Authors: Axelrod Daniel I.
Published: September 2022

Mid-Miocene floras from the western interior regularly have numerous exotics allied to broad-leaved deciduous hardwoods and conifers now in the eastern United States and Asia. Successive floras from local areas show that exotics were eliminated first from western Nevada, later in Oregon and Washington to the north where precipitation was higher, as it is today. Precipitation requirements of allied modern species suggest that the exotics were reduced significantly at 15 Ma as summer rainfall (May-August) decreased to <35 per cent of the annual total. The decrease seems attributable to the spread of the East Antarctic ice sheet (15 Ma) and resultant cold water upwelling that produced drier summers. Commencing 8-7 Ma, the spread of the West Antarctic ice sheet and Arctic polar ice, with resultant further cold water and drier summers, continued to reduce exotics and confine them to relict sites in mild coastal areas down to the close of the Tertiary.
Revision of Callistemonites indicus Bande, Mehrotra & Prakash from the Deccan Intertrappean beds of Mandla District, Madhya Pradesh
Authors: Bande M.B. , Mehrotra R.C. , Awasthi N.
Published: September 2022

The description and affinity of the fruiting axis Callislemonites indicus Bande, Mehrotra & Prakash 1986 reported from the Deccan Intertrappean beds, Shahpura in Mandla District, Madhya Pradesh have been revised. It is an incompletely preserved cast of the fruit with well-preserved seeds and shows close resemblance with that of Musa instead a fruiting axis Callistemon-Melaleuca as suggested earlier. It is very similar to the fossil fruit Musa cardiosperma Jain which was described from the Deccan Intertrappean beds of Mohgaonkalan, Chhindwara District and hence has been placed in the same species. This provides further evidence of the wider distribution of Musa in central India during Late Cretaceous- Early Palaeocene time.
Thrust Areas in Palaeobotany
Authors: Tiwari R.S.
Published: September 2022

NA
Taphonomy of spores and pollen in Gondwana Sequence of India
Authors: Tiwari R.S. , Vijaya  , Misra B.K.
Published: September 2022

Theoretically only few sedimentary rocks are devoid of spores and pollen; however, it is the taphonomic factors viz., necrolysis, stratinomy and diagenesis, that make them barren, impoverished or polleniferous. Therefore, high fossilization potential of spores-pollen from predominantly terrestrial and complex package of sediments spaning from Early Permian through Early Cretaceous has been utilized to build a comprehensive data-base on the Gondwana palynostratigraphy and also to assess their loss by taphonomic factors. Advent of Gondwana sedimentation witnesses glacio-fluvial-lacustrine environments and rare marine transgressions during Asselian-Sakmarian Talchir Formation. Adverse effect of moraine transport on preservation of spores-pollen from boulder bed matrix of Talchir Formation is evident. In the subsequent Permian Sub-period, depositional conditions favour the formation of enormous coal deposits. Low grade coals, shales and fine-grained sandstones normally contain less degraded spores-pollen from the Upper Gondwana red beds of Lower Triassic Panchet Formation and Intertrappean beds of Lower Cretaceous Rajmahal Formation are interpreted to have undergone chemical and thermal diagenesis, respectively. Spores-pollen from sediments deposited under anoxic and alkaline conditions (with high contents of pyrite, siderite and phosphorites) show that their preservation is related to syn- and post-depositional conditions. Whereas, sediments influenced by plate movement and tectonic activity in Peri-Gondwana Tethyan Himalaya have spores-pollen showing the effect of post-depositional diagenetic factors.
Upper gondwana plants from the Puna formation, SouthernXizang (Tibet)
Authors: Zhiyan Zhou , Yiming Wu
Published: September 2022

A plant megafossil assemblage comprising Cladophlebis sp., Pachypteris specifica Feistmantel, a fragmentary leaf, Ptilophyllum acutifolium Morris, Araucarites minutus Bose & Maheshwari, Elatocladus tenerrimus (feistmantel) Sahni, Brachyphyllum (Allocladus?) sp. Coniferocaulon rajmahalense Gupta. Coniferocaulon? sp. and roots, is reported from the coal bearing Puna Formation, Tingri District, southern Xizang, Tibet. This assemblage represents the assemblage Zone 9 (Sukh-Dev, 1988) of India and is considered Early Cretaceous in age. The similarity between the Puna florule and the Indian flora extends further the northern limits of Gondwanaland into southern Tibet.
Plant megafossils from the Siwalik sediments of Koilabas, central Himalaya, Nepal and their impact on palaeoenvironment
Authors: Prasad Mahesh
Published: September 2022

A systematic study on plant megafossils comprising mainly leaf-impessions from the Himalayan foot-hills near Koilabas, Nepal has been carried out. The comparative study of plant fossils with the extant taxa reveals the occurrence of 26 new species belonging to 14 dicotyledonous families. The floral assemblage suggests that tropical evergreen to moist deciduous vegetation flourished around Koilabas area during the Siwalik time. The habit and habitat of the comparable extant taxa indicate a warm humid climate all along the foot-hills during the Mio-Pliocene. The presence of a sizeable number of Indo-Malayan taxa in the present assemblage shows fair exchange of floral elements between two subcontinents and further extension towards Nepal territory. The significance of physiognomic characters of the leaf-impressions in relation to environment has also been discussed.
Possible evidence of bacterial degradation in Glossopteris flora of India
Authors: Srivastava A.K. , Tewari Rajni
Published: September 2022

Scanning electron microscopy of cuticles of glossopteris fructification (Sculum type) recovered from the Upper Permian sequence of Jharia coalfield demonstrates damaged cellular tissue and bacteria like structures. Occurrence of bacteria over the marred surface of seed cuticle possessing plaque/pit suggests role of micro-organisms in biodegradation of Glossopteris flora.
A tribute to Gurdip Singh (1932-1991)
Authors: Singh H.P.
Published: September 2022

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Jainiella-A new dinoflagellate cyst genus from the Upper Cretaceous of Cauvery Basin, India
Authors: Khowaja-Ateequzzaman  , Garg Rahul
Published: September 2022

A new dinoflagellate cyst genus Jainiella is described from Trichinopoly Formatiom (Upper Cretaceous), Cauvery Basin, southern India. It is characterised by subspherical to oval cyst having an autophragm without apical and antapical horns and possessing an intercalary, type 31 archaeopyle. The genus Trivalvadinium Islam 1983 is emended and T. plenum Islam 1983 is transferred to the new genus Jainiella.
Protoeusaccites gen. nov.- A case of transitionary, character-state in saccus structure in the late permian bisaccate pollen
Authors: Tiwari R.S. , Ram-Awatar
Published: September 2022

A new non-striate, bisaccate pollen genus- Protoeusaccites gen. nov., is described from the Middle Member of the Pali Formation, South Rewa Gondwana Basin, Madhya Pradesh, India. The grains are diploxylonoid with a prominent central body having a monoletoid mark or a thin area. The sacci with partial cavity in their chamber show a unique transitionary character-state, between the “Protosaccate” and “Eusaccate” in their structure.
Dinocyst biostratigraphy of Santonian-Maastrichtian formations of the Western Gulf Coastal Plain, southern United States
Authors: Srivastava Satish K.
Published: September 2022

This palynological investigation of Santonian-Maastrichtian formations of Texas, U.S.A. consists of an examination of 82 outcrop samples from 19 stratigraphic sections exposed in 9 countries in a north-south trend from about Dallas to Kinney. The Austin Chalk Formation, the Taylor Group, and the lower Navarro Group are examined for palynological data. Most of the samples are rich in dinocysts assemblages. In a total assemblage of 163 palynomorphs species in 95 genera, 111 dinocyst species of 60 genera, 6 acritarch species of 5 genera, and 46 spore pollen species of 33 genera are recognized and their stratigraphic distribution documented. Systematic descriptions and illustrations of all dinocysts and acritarch taxa are given. Spore-pollen taxa occur sporadically in the studied sections and thus are only listed, illustrated and their occurrences noted in the text.

The stratigraphic distribution of dinocysts species indicating the Santonian age can be recognized by the presence of Chatangiella granulifera, C. robusta, C. spectabilis, Phelodinium gaduatum and Spinidinium lanturnum. The characteristic species of Campanian assemblage are Cannosphaeropsis hyperacantha, C. utinensis, Ceratiopsis subquadra, Chattangiella armata, C. williamsii, Diconodinium martianum, Dinogymnium denticulatum, D. enclaense, D. nelsonense, Impagidinium cristatum, I. microarmum, Rottnestia borusstca, Triblastula utinensis and Xenascus gochtii.

The appearance of the following dinocysts species viz., Andalusiella acicornula, Areoligera senonensis, Ceratiopsis navarriana, Glaphyrocysta retiintexia, Lejeunecysta decorinassa, L. byalina, Litosphaeridium fenestreconum, Palaeocystodinium australinum, Phelodinium tricuspe and Thalassiphora bononiensis in the Maastrichtian is significant.

Pollen occurrences indicate that the land area, west of the Senonian epeiric sea, was terrigenous source in the Santonian and the Late Maastrichtian whereas the land on the east of the eperic sea was the source in the Campanian.
Organic-walled microfossils of doubtful origin in Permian and Triassic sequences on peninsular India
Authors: Tiwari R.S. , Tripathi Archana , Vijaya
Published: September 2022

The Permian and Triassic succession of the Indian Gondwana Sequence, with the exception of Lower Permian Talchir Formation, has been considered to be deposited in fluviatile-lacustrine environment-Palynological investigations of these deposits have revealed the presence of rich assemblages of spores, pollen and other organic-walled microfossils of doubtful origin (OMIDO) belonging to the group Acritarcha in its broader sense. Recent discoveries of marine signatures from these deposits depicted by sedimentological, biotic and chemical features strongly prompt for a detailed investigation of OMIDO’s for their authentic application in determining the palaeoenvironment. Sporadic or consistent occurrence of OMIDO’s has been recorded from Talchir to Panchet formations at various time intervals. The increase in the brackish water regime on to the Indian Peninsula near the deltaic sea-shore regions could have provided suitable environment from time to time for growth of OMIDO’s. This could have occurred due to the well-known global transgressions during Permian and Triassic times. It is, therefore, important that the non-marine nature of Indian Gondwana should be skeptically viewed in order to find possible marine signatures in this sequence. The present study reveals that there had been three major diversity acme phases of OMIDO’s during Permian, viz., (i) Talchir/Karharbari, (ii) Upper Barakar, and (iii) Upper Raniganj Formations. They broadly coincide with the onset of regression. Although the data is meager, a similar trend in occurrences of OMIDO’s has been observed in the Triassic.
Some more leaf-impressions from the Himalayan foot-hills of Darjeeling District, West Bengal, India
Authors: Antal J.S. , Prasad Mahesh
Published: September 2022

In the present paper five well-preserved leaf-impressions collected from the Siwalik sediments of Sevok Road cutting and Ramthi River sections in Darjeeling District, West Bengal have been described. These are Xanthophyllum mioflavescens sp. nov., Pterospermum siwalicum sp. nov., Swintonia miocenica Awasthi & Prasad, Millettia oodlabariensis sp. nov., and Glochidion (=Phyllanthus) palaeohirsutum sp. nov. showing close resemblance with the extant taxa Xanthophyllum flavescens Roxb., Pterospermum semi-sagittatum Ham., Swintonia floribunda Griff., Millettia albiflora Prain and Glochidiom birsutum Muell., of the families Xanthophyllaceae, Sterculiaceae, Anacardiaceae, Fabaceae and Euphorbiaceae, respectively. The presence of these elements in the Siwalik sediments further suggests the prevalence of tropical humid climate in the region during sedimentation.
Fossil woods from the Siwalik sediments of Darjeeling District, West Bengal, India
Authors: Antal J.S. , Prasad M. , Khare E.G.
Published: September 2022

The fossil woods described in this paper form the first report from the Himalayan foot-hills near Oodlabari, a small town on Siliguri-Guwahati Highway, Darjeeling District, West Bengal. These belong to the extant genera Baubinia Linn. and Diospyros Linn. of the families fabaceae and Ebenaceae, respectively and have been described as Baubiniumpalaeo malabaricum Prakash & Prasad and Ebenoxylon miocenicum Prakash. They indicate the prevalence of tropical humid climate in the foot-hills during Siwalik sedimentation.
Indian Tertiary angiosperm pollen: A critical assessment
Authors: Venkatachala B.S. , Saxena R.K. , Singh H.P. , Kar R.K. , Tripathi S.K.M. , Kumar M. , Sarkar Samir , Mandal J. , Rao M.R. , Singh B.D. , Mandaokar B.D. , Ambwani K.
Published: September 2022

More than 400 genera and 1000 species of angiosperm pollen are known from the Tertiary sediments of India. It has been observed that large numbers of these taxa are based on one or few specimens and meagre morphological differentiation. Thus, their usefulness is limited, Thanikaimoni et al., (1984) and Venkatachala et al., (989), in an effort to distinguish important stratigraphic and environmental markers, selected several taxa and illustrated, discussed and compared them with the African pollen. In continuation, holotypes, paratypes and other specimens of selected species available at the repository of the Birbal Sahni Institute of Palaeobotany, Lucknow have been restudied, critically evaluated and their morphological limits circumscribed to make them more useful and applicable for age determination and stratigraphic correlation as well as for Palaeoenvironmental interpretation with emphasis on their affinity with extant taxa.
Professor S.D. Saxena
Authors: Tiwari R.S.
Published: September 2022

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Biopetrological study of Mulug coal belt, Godavari Basin, Andhra Pradesh, India
Authors: Sarate O.S.
Published: September 2022

Biopetrological investigation of 12 coal seams from Mulug coal belt of Godawari Basin has been carried OUID evaluate their economic potentials. The coal seams are associated with the Karharbari and Barakar of the Lower Gondwana sequence. The maceral study has revealed that seams IV A, IV , 111 B, II, I below index, I and IA contain vitric coal. However, IV below index, III and I B seams are characterized by a mixture of both vtric and fusic coals. Besides, III A and II below index seams contain fusic coal. The microlithotype analysis indicates that the vitric coal has the dominance of vitrite, clarite and duroclarite constituents. The mixed type of coal contains variable frequencies of vitrite and inertite with intimate association of clarite, durite, trimacerite and carbominerite microlithotypes. However, fusic coal has overall dominance of inertite with carbominerite. The reflectance study revealed that I B, I and I below index, IV below index and the lowermost IV A seams have attained high volatile bituminous C rank. Whereas coal of II below index seam is represented by transitional stage of rank between high volatile bituminous C and sub-bituminous A. the coal seams III B and III A contain coal of high volatile bituminous B rank. However, the seams III and II are characterized by coal having rank ranging between high volatile bituminous C to B. Seam I A contains coal of high volatile bituminous C to A rank. However, seam IV comprises coal having reached high volatile bituminous A stage.
Arecoideostrobus moorei gen. et sp. nov., a palm rachilla from the Deccan Intertrappean beds of India
Authors: Bonde S.D.
Published: September 2022

A petrifted part of a rachilla from an inflorescence of Arecaceae has been described from the Deccan Intertrappean beds exposed at Nawargaon-Maragsur area of Wardha District, Maharashtra, India. The inflorescence shows a spiral arrangement of flower triads, each triad in a pit with a central large pistillate flower having a two whorled perianth and a superior ovary flanked on either side by a small staminate flower. The inflorescence axis exhibits wide variable cortex with ftbre bundles and empty sacs, a reduced vascular region with a very compact arrangement of fibrovascular bundles, floral traces and diminutive and fusion bundles enclosing a small pith. Morphological and anatomical characters ofthe rachilla suggest its affinity with the members of sub-family Arecoideae of the family Arelaceae.
Differential morphographic identity of Gondwanic palynomorphs
Authors: Tiwari R.S. , Vijaya
Published: September 2022

The exine structures, bauplan and germinal apertures are the basic characters for the morphographic of fossil spores and pollen. The apparent but unreal form-similarities of some bisaccate pollen taxa or Sporae dispersae from Gondwanaland on one hand and those in the contemporary Euromerian sequences on the other, have been sorted out in this paper. Trends of different exine structures and saccus organization have been identified in pollen. This concept has been exemplified by the fact that the pollen taxa Lunatisporites, Lueckisporites and Klausipollenites of the north possess mostly imperfect reticulate, compactly placed grana, columnar elements, rodlets, vermiculale, verrucae or similar elements mixed together, rounded or multifaceted islands of various shapes and sizes, incomplete or even isolated closely packed muri as exinal elements which make the infra-structure of the sexine in the corpus. In contrast to this trend, the major pattern of exine structure in apparently similar taxa of the Gondwanaland is different; most of the pollen groups exhibit perfectly infrareticulate structure on corpus with complete muri and distinct meshes.

Such a differential morphographic identity may lead to a more rational model of the palaeo-phytogeography based on palynofossils, because the genuine similarities and differences could be effectively used in delimiting the floral provinces. The distinctions in the mother vegetations, which have had produced pollen and spores in two region, corroborate the distinctions in the groups of palynotaxa discussed here. This paper proposes the theory of the Apparent Form Similarity (AFSIM Factor) and highlights certain lines of differentiation amongst the similar-looking but basically different spore-pollen components produced by unrelated plant groups. Some aspects of palynofloral distribution vis-à-vis climate changes through Gondwana have also been discussed.
Some observations on the occurrence of Cycadophytes and Bennettitales in the East Coast Upper Gondwana Athgarh Sandstone, Cuttack and Khurda districts of Orissa, India
Authors: Patra B.P. , Sahoo N.K.
Published: September 2022

Athgarh Sandstone is rich in plant megafossils, in which the pteridophytes and conifers are dominated followed by Bennettitales and Cycadophytes. The species described in this paper are: Ptilophyllum acutifolium, Ptilophyllum spp., Pterophyllum kingianum, Pterophyllum sp. cf. P. distans, Otozamites penna, Otozamites sp. cf. O. kachchhensis, Anomozamites fissus, Dictyozamites sp. and Taeniopteris spatulata. A comparison of this assemblage with similar other assemblages from the Lower Cretaceous of India has also been made.
Oligocene flora from Makum Coalfield, Assam, India
Authors: Awasthi N. , Mehrotra R.C.
Published: September 2022

The coal bearing Oligocene sediments exposed in the Makum Coalfield, Assam contain rich assemblage of mega-plant remains. Out of a large number of leaves and fruits collected from the associated sediments at Baragolai. Ledo-Tirap and Tipongpani collieries of the Makum Coalfield, 24 species of dicotyledonous taxa have been identified. Of these, 22 are represented by leaves belonging to the genera Saccopetalum (Anonaceae); Calophyllum, Garcinia, Kayea (Clusiaceae); Pterygota (Sterculiaceae); Santiria (Burseraceae); Heynea (Meliaceae); Nephelium (Sapindaceae); Lannea, Mangifera, Parishia (Anacardiaceae); Rhizophora (Rhizophoraceae); Terminalia (Combretaceae); Memecylon (Memecylaceae); Avicennia (Avicenniaceae); Alstonia (Apocynaceae); Myristica (Myristicaceae), Apollonias (Lauraceae) and Bridelia (Euphorbiaceae). The remaining two taxa are based on fruit/seed comparable to those of Dalbergia and Entadu of Fabaceae.

The distribution pattern of comparable modern taxa of fossils and keeping in view the great amount and variety of plants preserved in the sediments, it is inferred that thick tropical evergreen to moist deciduous forest existed in this part of northeast India during Oligocene. Occurrence of Avicennia, Rhizophora and Terminalia catappa suggests deltaic, mangrove or agoonal deposition of coalseams and associated sediments in the Makum Coalfield.
Megaspores of some Indian species of Isoetes L. and comparable living and fossil forms
Authors: Srivastava G.K. , Shukla P.K. , Wagai S.O.
Published: September 2022

Megaspores of five Indian species of Isoetes., viz., I. coromandelina, I. indica, I. panchananii, I. tuberculata and I. rajasthanensis have been studied under light microscope and scanning electron microscope and Sem and compared with those of modern Salaginella and dispersed fossil megaspores.