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The earliest representative of Glossopteridales is known by the leaves discovered from India and Australia (Brongniart 1822–28) under the genus Glossopteris as Glossopteris browniana var. australasica and Glossopteris browniana var. indica. Later discovery proved the presence of similar leaves in all the Gondwana continents, i.e. India, Australia, Antarctica, South America and Africa ranging from late Carboniferous to entire span of Permian to early Triassic. Such distribution pattern provides major evidence for the theory of continental drift. As a unified character, these tongue–shaped leaves show reticulate venation pattern and a midrib. Later, non reticulate and non midrib leaves were also considered as ally due to their close association with the leaves of Glossopteris and together they are assigned to Glossopteridales consisting of different genera, e.g. Gangamopteris, Rubidgea, Euryphyllum, Palaeovittaria, Maheshwariphyllum, Rhabdotaenia, Sagittophyllum, Pteronilssonia, Surangephyllum, Gondwanophyllites, Laceyphyllum, Belemnopteris, etc. Later, cuticular study, discovery of fertile structures in attachment with leaves increased the number of species. In addition, permineralized leaf fossils with anatomical features have also been described under new species of Glossopteris. Fertile structures of glossopterids are mainly discovered in attachment with leaves or in attachment with scale leaves or bracts. Leaf borne fertile structures are known by multiovulate ovule/ seed bearing organ with or without stalk, e.g. Ottokaria, Dictyopteridium, Scutum, Senotheca, Cistella, Plumsteadiostrobus, Jambadostrobu, Lanceolatus, Vanus, Pluma, Hirsutum, etc. Scales or bracts showing branched and unbranched cupulate organs are other mode of fertile structures, e.g. Lidgettonia, Partha, Denkania, Bifariala, Nogoa, Gladiopomum, Rusangea, Rigbya, Mooia, etc. Distinct seed bearing Arberia, Dolianitia–type of fructifications, Eretmonia, Glossotheca type of sporangia bearing scale leaf or bract, Arberiella–sporangial mass and a variety of dispersed seeds are also accredited to glossopterids. Ironically, leaves and fructifications have not yet been found in attachment with stem, however, fossil woods with araucariod pits, e.g. Dadoxylon/ Araucarioxylon found in alliance demonstrate their affiliation with glossopterids. Vertebraria–axes commonly observed in the sediments exemplify the rooting behaviour of the glossopterids. Combination of different types of leaves consisting of more than 130 species under closely allied genera, thirty-five to forty types of fructifications grouped under multiovulate and branched types together with seed–bearing structures, varied type of morphological, cuticular and structural features amply demonstrate that Glossopteridales had sundry approach for development, endurance and evolution and in all likeness represent different taxonomic characteristics.

Plant–insect interaction is dominant in the extant flora and it is estimated that more than one million species of insects directly or indirectly survive on plants. In comparison, such association is limited in extinct flora, mainly due to problem in identifying structural features associated with the insect wronged plant fossils. Concerted efforts and comparative structures observed in extant flora have unfolded the mystery of insect herbivory in fossil plants. The study has helped to understand the feeding pattern and evolutionary features of insects during different time intervals and provide significant evidence to comprehend the co–evolution of plant and insect in the geologic past. Herbivorous insect wings discovered from different Gondwana successions of India belong to families and genera of Homoptera, Heteroptera, Mecoptera, Coleoptera and Blattoidea. The remains of Coleoptera and Mecoptera in all probability represent the earliest record in fossil flora. Insect herbivory is well recognized in Indian flora in the form of insect galls, chewing and eaten marks of leaf margin, disfigurement of lamina, egg–like pouches, trailing marks, mining activity, etc. The available records demonstrate the presence of well-knit coalition of insect–plant interaction in Indian Gondwana successions. Diverse type of insect herbivory recovered in the Gondwana flora of India implies that insects used the plants for various purposes such as feeding, shelter and laying eggs for their development/ survival and the process has thus helped in the development and evolution of insects in consortium with plants.

Morphological and taxonomic features of dispersed sterile scale leaves collected from the Barakar Formation of Pench, Kanhan and Pathakhera coalfields of Satpura Gondwana Basin, Madhya Pradesh are described. The scale leaves are normally described as morphological types without their assignment to taxonomic status. Due to this practice, the identity and significance of the scale leaves have gone astray in the Glossopteris flora. The presence of large number of sterile scale leaves with different morphological features in the present assemblage has helped to discuss their structure, nature and affinity. The scale leaves have been assigned to different genera and species namely Pantolepis indica gen. et sp. nov., Penchiolepis gondwanensis gen. et sp. nov., Penchiolepis indica sp. nov., Surangelepis ambarai gen. et sp. nov., Surangelepis elongatus sp. nov. and Utkaliolepis indica Tiwari et al. 2009.

The morphological and cuticular features of well-preserved leaves of Glossopteris stenoneura Feistmantel collected from Barakar Formation of Churulia area, Raniganj Coalfield are analyzed. The study indicates that spathulate shaped leaves are distinct in having narrow-elongate trapezoidal meshes near the midrib and short, narrow meshes near the margin of leaves. Cuticle is amphistomatic, the surface of upper cuticle characteristically shows fine striations over the vein area. Stomata are anomocytic, ovalelongate with cutinized guard cells. Subsidiary cells of lower cuticle demonstrate papillae overhanging stomata.

The present paper deals with the plant megafossil assemblage from the Maitur Formation, the lower part of Panchet Group of rocks, unconformably overlain by coal bearing Raniganj Formation in Raniganj Coalfield, West Bengal. The plant fossils are collected from two localities exposed in Nonia Nala Section near Asansol, Burdwan District, West Bengal. The assemblages are represented by the typical elements of Glossopteris flora, viz. Trizygia speciosa, Neomariopteris hughesii. N. lobifolia, Dichotomopteris lindleyii, D. ovata, Glossopteris indica, G. tenuifolia, G. emarginata, G. angustifolia. G conspicua, G. intermedia, G. retifera, G. gopadensis, G. taeniensis, Glossopteris sp. cf. G. dhenkanalensis, one new species G. burdwanensis sp. nov., glossopterid scale-leaves and seed-like body. The age of Maitur Formation has been assigned to Early Triassic but the plant fossil assemblages are comparable with the Late Permian plant fossils of Kamthi, Pachhwara and Bijori formations in having narrow leaf forms of Glossopteris. The investigation supports the view that there is no floral break at the Raniganj-Panchet Boundary and flora of Maitur Formation in all probability represents the ultimate stage of Glossopteris flora in Raniganj Coalfield before the onset of Early Triassic Dicroidium flora in Deoli/Hirapur Formation belonging to upper part of Panchet Sequence in Raniganj Coalfield, West Bengal.

Well preserved leaves discovered from the Early Permian sequence of Barakar Formation of Pench Valley Coalfield, Satpura Gondwana Basin demonstrate the earliest occurrence of taeniopteroid leaves in Lower Gondwana formations. Such leaves are mostly recorded from the Late Permian sequence of Raniganj Formation and assigned to different genera, Taeniopteris Brongniart, Macrotaeniopteris Schimper and Rhabdotaenia Pant. The review of all the known records, the examination of type and figured specimens and present study indicate that plausibly all the taeniopteroid leaves of Lower Gondwana belong to the genus Rhabdotaenia Pant (1958) and the species, Rhabdotaenia danaeoides (Royle) Pant, Rhabdotaenia harkini Pant and Rhabdotaenia fibrosa Pant are characterized by large sized leaves whereas new species Rhabdotaenia pantii sp. nov. is instituted for small size-obovate shaped leaves discovered from the New Sethia open cast mine of Pench Valley Coalfield, Madhya Pradesh.

The morphological and cuticular features of new sterile, branched coniferous foliage shoot, Walkomiella sahnii sp. nov. collected from the carbonaceous shale samples of Karharbari Formation, Rajhara Colliery of Daltonganj Coalfield, Jharkhand State are described. New species is characterized by homomorphic leaves showing rhomboidal shape, acuminate apex, broad base, uninerved; cuticle is differentiated into thick abaxial and thin adaxial surfaces and stomata are irregularly distributed only on adaxial surface. Fertile structures are not known. Specimen represents the first report of Walkomiella as coalified compression in Lower Gondwana sediments of India. Earlier records of W. indica Surange & Singh 1951 and Walkomiella sp. are based on dispersed cuticles of leaf and seed bearing shoot recovered through maceration of samples.

The present investigation corroborates with the vegetative counterparts belonging to conifers recovered from the fossiliferous horizons of the Upper Gondwana succession of the Early Cretaceous age. The succession, in addition, to the species of Filicales, Bennettitales, Cycadales and Coniferales, also revealed the rich assemblage of Araucarites, viz., A. cutchensis, A. minutus and Araucarites sp.

Plant fossils collected from Bhareli Formation exposed in Pinjoli Nala section situated on Bhalukpong Bomdila Road section, West Kameng District, Arunachal Pradesh are described. The assemblage is represented by Gangamopteris karharbariensis, Glossopteris communis, G. stenoneura, G. longicaulis, G. indica, G. tenuifolia, G. spatulata, G. taeniensis, G. subtilis, Glossopteris sp. cf, G. decipiens, Glossopteris sp., Noeggerathiopsis hislopii, Samaropsis ganjrensis, seed bearing organ, Vertebraria indica, scale leaf and equisetalean axes. The flora is comparable with the floristics of Lower Barakar Formation of India.

A plant fossil assemblage comprising of Matonidium indicum, Sphenopteris sp., Cladophlebis indica, Ptilophyllum cutchense, P. acutifolium, Taeniopteris spatulata, T. vittata, Pagiophyllum sp., Brachyphyllum sp., Araucarites cutchense, Elatocladus tenerrinus, E. sp., E. kingianus and Elatocladussp. A has been described from a new locality of the Bairam-Belkher area in District Amravati, Maharastra, and District Betul, Madhya Pradesh. Ptilophyllum and Matonidium are the most abundant genera in this assemblage. An attempt has also been made to compare the present assemblage which shows an affinity with the Lower Cretaceous assemblages of Peninsular India, i.e. Himmatnagar, Gardeshwar, Gollapalle, etc. On the basis of various taxa belonging to Bennettitales and Filicales, a warm and humid climate has been interpreted.

Plant fossil assemblage of Auranga Coalfield recovered from the Fireclay of Barakar Formation being mined in Murup and Datum areas of Palamau district, Bihar is represented by various species of the genera Neomariopteris, Gangamopteris, Glossopteris, Saportaeae, Rhipidopsis and Ginkgoites. Glossopterid-ginkgopsid association is the characteristic feature of this flora. Which is closely comparable with the Glossopterid-ginkgopsid association of the Hura Coalfield, Rajmahal Hills, Bihar.

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.

The glossopterid group of plants was the most dominant constituent of the Permian vegetation of the Gondwana Supercontinent. During last one hundred and fifty odd years, a staggering amount of data has accrued on leaves, wood, root, fructifications, seed and pollen that possibly belonged to this group. Evolutionary pathways with the group, however, are yet little understood. Considering the venation and epidermal features of the leaves, two patterns are unfolded; one with leaves having dichotomizing, almost parallel veins and stomata in linear rows, the other with dichotomising and anastomosing veins and stomata irregularly distributed in the mesh areas. Oldest glossopterid fructifications, viz., Arberia/Dolianitia show a certain resemblance with the cordaitalean fructifications, thus suggesting that group of plants with Cordaites/Noeggerathiopsis/Pantophyllum type leaf and Arberia/Dolianitia type infructescence probably was the precursor of the glossopterids. Overall evidence suggests the development of this group of plants along two successive lineages.

Morphological and systematic investigation of plant fossils namely Equisetales (Phyllotheca, Lelstotheca, Phyllothecan cone, Trizygia), Filicales (Neomariopteris, Palasthalia gen. nov. showing sterile frond with auriculate base and pecopteroid venation pattern), glossopterids (leaves of Euryphyllum, Gangamopteris, Glossopteris, Palaeovittaria, Gondwanophyllites, Maheshwariphyllum gen. nov. having complete midrib and dichotomizing lateral veins, Parth,, Scutum fructifications), Cordaitales (Noeggerathiopsis, Cordaites), detached seeds of Samaropsis and Cordaicarpus and scale leaves from different seams of Barakar Formation of Raniganj Coalfield are described. The flora of the lower seams (nos. B II-B IV) is comparatively more diversified and shows affinity with the Karharbari flora, whereas the flora of upper seams (nos. B V-B VII) is monotonous in composition in being mostly represented by Glossopteris species. The composition of the flora in relation to evolution and climatic changes suggests lineage towards the development of midrib character in the glossopterid leaves and existence of temperate climate with a change from warm moist to warm dry condition.

The paper describes megaspores belonging to the genera Srivastavaesporites, Trilaevipellitis, Jhariatriletes, Talchirella, and Barakarella gen. nov. recovered from the Lower Barakar shales of Churulia area, East Raniganj Coalfield, West Bengal. Megaspores have been studied both under dry as well as under wet conditions through controlled maceration. The exosporium and inner body have been found in all the megaspores. Particular attention has been given to the morphological features of the inner body and their taxonomic value is stressed. Barakarella gen. nov. is characterized by a baculose exosporium and cushioned inner body.

Five new plant elements from the Barakar and Raniganj stages of Auranga Coalfield are described. The Barakar plants include a new dimorphic leaf whorl genus Diphyllopteris and two new species Neomariopteris barakarensis sp. nov., and Ottokaria biharensis sp. nov., Plumsteadia lanceolata sp. nov. represents a new type of fructification from the Raniganj Stage.

The genus Lelstotheca, known so far only from the Barakar Formation of Rajmahal Hills, Bihar is reported from the Barakar Formation of Raniganj Coalfield, West Bengal. The genus is represented by two species, viz., L. robusta (Feistmantel) Maheshwari and L. striata sp. nov. The new species is characterized by the presence of interconnecting striations running parallel to the median vein of the leaves. The taxonomic position of the genus and its records elsewhere are also discussed.

The present paper describes for the first time a mioflora of Barren Measures age from the Auranga Coalfield. The assemblage (13 genera and 26 species) is dominated by striate-disaccates along with a good amount of Densipollenites. The quantitatively significant genera are Faunipollenites, Densipollenites, Striatites, Verticipollenites, Scheuringipollenites and Lahirites. Two species, Densipollenites brevis and Striatopodocarpites crassistriatus are new.

A good assemblage of Karharbari plant fossils has been recovered for the first time from Lower Gondwana beds of Auranga Coalfield, Bihar. The assemblage is characterised by the presence of Neomariopteris (N. hughesi), Gangamopteris (G. cyclopteroides, G. clarkeana), Glossopteris (G. damudica, G. communis), Vertebraria (V. indica), Noeggerathiopsis (N. densinervis), Euryphyllum (E. whittianum) and Samaropsis (S. ganjrensis). The flora compares closely with the known Karharbari assemblages of India.

Palynological assemblages from Coal Measures (Lower Permian) of four areas, namely Umaria, Birsinghpur Pali, Anuppur and Chirimiri of South Rewa Gondwana Basin, Madhya Pradesh are described. A brief description of the stratigraphy and geology of the relevant sections is given. Available information on some other significant Coal Measures (Barakars) has been taken into consideration for bringing out their palynological characteristics with reference to stratigraphy. Qualitative and quantitative distribution of palynotaxa in various areas reveal that the miofloral assemblages reported here are closer to the Karharbari mioflora. A rich palynofloral assemblage is reported for the first time from Coal Measures of Anuppur.

Arberia surangei sp. nov. has been described from the coal-bearing (Karharbari?) formation of Birsinghpur Pali, Madhya Pradesh. The species of Arberia, so far known from India, are also reviewed.

The paper describes for the first time the Karharbari miospore assemblage from the Auranga Coalfield. The mioflora (19 genera and 39 species) is characterized by the dominance of trilete taxa Callumispora and Brevitriletes together with monosaccates, Parasaccites, Caheniasaccites and Virkkipollenites. Other quantitatively significant genera are Faunipollenites, Psilalacinites, Microbaculispora, Kibambaites, Verrucosisporites and Latosporites.

Fossil plant asssemblages around Marhwas area in Sidhi District are represented by one species each of Trizygia, Neomariopteris and Scutum, a fern and 24 species of Glossopteris. Floristic composition indicates Raniganj-Kamthi affinities and a warm-temperate climate. High percentage of small-sized leaves and poor representation of pteridophytes in the flora suggest drier conditions and low humidity.

Plant fossils belonging to the Talchir and coal-bearing formations (Lower Permian) of four areas, namely Umaria, Birsinghpur Pali, Anuppur and Chirimiri of the South Rewa Gondwana Basin are described. The Talchir flora is represented by a few species of Gangamopteris and Noeggerathiopsis, while the megafossils from the coal-bearing formation are represented by various species of Glossopteris, Gangamopteris, Noeggerathiopsis and Vertebraria. A new species of Noeggerathiopsis, N. minor, has been recognized. It has also been observed that the flora of the coal-bearing beds in these areas is characterized by the dominance of Gangamopteris and Noeggerathiopsis. This suggests that these beds of the South Rewa Gondwana Basin are equivalent to the Karharbari ‘Stage’ of Peninsular India.

The Lower Barakar flora of Raniganj Coalfield shows close affinity with the Karharbari flora. The venation pattern of different leaf genera and its evolutionary trends are discussed. Insect wings, insect-affected leaf and stem specimens are recorded. On the available evidences, the insect/plant relationship during the early phase of Glossopteris Flora is discussed.

Sphenopsids from Lalmatia Incline (Lalmatia Top Seam, Barakar Formation), Rajmahal Hills, Bihar, belong to Sphenophyllum gondwanensis sp. nov., Lelstotheca sp. and equisetalean axes. Previous records of northern species of Sphenophyllum in Lower Gondwana sediments are reviewed and reassessed.

Eleven species of Glossopteris, viz., G. communis, G. sp. cf. G. nidpurensis, G. divergens, G. retifera, G. browniana, G. stricta, G. decipiens, G. fusa. G. sp., G. conspicua, G. leptoneura and scale leaves have been described in detail. The miospore assemblage (18 genera & 36 species) is dominated by striate-disaccates and triletes alongwith a good percentage of Densipollenites. Three species, Faunipoilenites multistriatus, Striatopodocarpites haploxylonoides and Striatites obliquus are new.

The paper deals with the morphological details of eleven species of Glossopteris, viz., G. indica, G. barakarensis, G. leptoneura, G. juchsii, G. conspicua, G. sp. cf G. ampla, G. pandurata, G. sp. cf G. intermittens, G. churiensis sp. nov., G. communis, G. browniana and Vertebraria indica. The mioflora (31 genera and 53 species) is dominated by striate disaccate pollen grains and trilete spores. A new non striate disaccate genus Aurangapollenites is instituted for the grains having pitcher shaped saccus arrangement.

The stratigraphical bearing of the various types of megafossils of the Karharbari, Barakar and Raniganj measures of the Lower Gondwana succession of Auranga Coalfield has been dealt in detail and the comparisons have also been made with the well-known floras of equivalent horizons of India.

A new species of Glossopteris, G. ornatus sp. nov., has been described from the Barakar Formation of the Raniganj Coalfield, West Bengal. The specimen shows ten leaves arranged in two close apparent whorls made up of closely arranged spiral leaves. All the leaves are morphologically similar and possess the same type of epidermal structures.