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This study reports the oldest fossil record of the genus Adina, A. vastanenesis n. sp., from the early Eocene of Vastan lignite mine (Cambay Shale Formation), Surat district, Gujarat. This fossil wood is characterized by diffuse porous wood, predominantly solitary tylosed vessels, simple perforations, scanty paratracheal to diffuse to sometimes diffuse in aggregate axial parenchyma, predominantly uniseriate to occasionally biseriate rays, and non septate fibres with bordered pits and shows its best resemblance with the modern species, Adina multifolia Haviland, belonging to the tribe Naucleeae (subfamily Cinchonoideae) of the family Rubiaceae. The present discovery becomes the first fossil record of the wood of Adina, which provides an insight about the Gondwanan origin either for the genus Adina or the tribe Naucleeae and its further dispersal to Southeast Asia.

A permineralized wood from the Deccan Intertrappean beds of central India is identified as a member of the family Lythraceae. The fossil wood found is similar to the modern genus Lagerstroemia and is characterized by diffuse porous to semi-ring porous wood, growth rings marked by marginal parenchyma, simple perforations, scanty paratracheal axial parenchyma, exclusively uniseriate homo to heterocellular rays and septate fibres with chambered crystals. This wood, Lagerstroemioxylon sp., is considerably older than the earlier known fossil records of this genus and confirms the presence of Lagerstroemia on the Indian subcontinent∼66 million years ago.

A new fossil wood of Hopeoxylon i.e. H. umarsarensis sp. nov. showing close resemblance with the modern wood of Sindora/Copaifera of the subfamily Detarioideae (family Fabaceae) is described from the Umarsar lignite mine of Kutch basin, Gujarat that belongs to the Naredi Formation of the early Eocene age. Detarioideae is one of the reinstated subfamilies of the Fabaceae with diversity much higher in tropical Africa than in South America or Asia. The relics of this subfamily are known from the Paleocene onwards from various horizons of America, Africa, Europe, India and Southeast Asia. This is the oldest fossil record of the genus Sindora/Copaifera which contributes towards the understanding of the origin and palaeo-dispersal pathways of this early-diverging subfamily within the early branching Fabaceae.

The present study deals with the reporting and description of the first fossil record of Mallotus Lour. fruit from all over the world. The edible parts of plants are too soft to be preserved and therefore, are rare in fossil records. Fossil fruit of Mallotus mollissimus (Geiseler) Airy Shaw (Euphorbiaceae), a rainforest tree, is described from the early Eocene Palana Formation (Gurha lignite mine) of northwest India. The occurrence of M. mollissimus, along with earlier described fossils from the area demonstrates the existence of dense tropical forests in the area during the depositional time in contrast to the desertic conditions in the area today. This discovery from the early Eocene succession substantiates the Gondwanan origin for the genus.

The Dioscoreaceae is a monocotyledonous family belonging to the order Dioscoreales. It includes two other families, the Burmanniaceae and the Nartheciaceae. Dioscoreaceae is the largest family of this order comprising 650–700 extant species included in four genera, which are widely distributed throughout warm temperate, subtropical and tropical regions. It is a pantropical family with a disjunct distribution. A new fossil species, Dioscorea eocenicus Mehrotra and Shukla, is described from the early Eocene sediments of Bikaner district (northwestern India). The campylodromous venation (having nine primary veins), disposition and course of tertiary veins, and other attributes of the fossil show its affinity with the modern genus Dioscorea of the family Dioscoreaceae. The origin, evolution, and diversification of the family have always been a matter of concern as different views and theories exist. This is the first fossil record of the family Dioscoreaceae from Asia. To date, fossils belonging to the family Dioscoreaceae have been retrieved only from Europe, Africa, and America. The present fossil from the Indian subcontinent, along with earlier recorded fossils of the family Dioscoreaceae provides new opportunities to trace the presence of Dioscorea (yams) in Gondwana since the Cretaceous. The presence of humid tropical forest in the region during early Eocene time has been interpreted based on this and other described fossils from the Gurha lignite mine.

Five petrified woods showing affinities with Hopea of the family Dipterocarpaceae, Berrya of Malvaceae, Eucalyptus of Myrtaceae and Diospyros of Ebenaceae are systematically described from the Cuddalore Sandstone Formation exposed near Puducherry, Tamil Nadu. Among them, four are new species, namely Hopenium tertiarum sp. nov., Berryoxylon cuddalorensis gen. et sp. nov., Eucalyptoxylon cuddalorensis sp. nov. and Ebenoxylon cuddalorensis sp. nov. Their modern counterparts indicate the existence of wet evergreen forests in the region during the depositional period. However, most of the modern comparable forms of the fossils are absent from the region today and found in the Western Ghats and northeast India having equable climate thereby indicating a change in the climatic conditions in the eastern coast of south India since the late Cenozoic.

The early Eocene is characterized by a warmer phase, even at high latitudes. The CO2 level ranged from 1000 to 2000 ppm due to the increase in volcanic activity. The climate dynamics of the Indian subcontinent and biotic exchange between the neighboring continents can be traced by studying the Eocene fossil assemblages which are nicely preserved in the rock records. Fossil records from early Eocene sites are important for their potential contribution in our understanding of interactions between climate and biota. In western part of the Indian subcontinent, extensive lignite deposits are known in the states of Gujarat (Kutch and Cambay basins) and Rajasthan (Barmer and Bikaner-Nagaur basins). These lignite deposits have been investigated for their faunal and floral content. Based on the nearest living relatives (NLRs), it has been concluded that a highly diversified tropical evergreen forest was present in most of the basins of western India and this fact has been supported by the equatorial position of the Indian subcontinent during the early Eocene. Fossil records of Rhamnaceae, Combretaceae and Lythraceae known since the Late Cretaceous in India indicate their possible Gondwanan origin.

A fossil of a mayfly nymph that shows similarities with the modern genus Teloganella Ulmer, 1939 of the family Teloganellidae is recorded for the first time from the Indian subcontinent. It is systematically described from the Gurha lignite mine of Bikaner, Rajasthan which belongs to the Palana Formation (late Paleocene-early Eocene). As assignment of the fossil to a modern species of Teloganella is difficult due to indistinguishable location of gills in the impression, a new species, Teloganella gurhaensis Agnihotri et al., sp. nov. is instituted to include this fossil naiad resembling the extant Teloganella.

Today the existence of tropical rainforests in the Indian subcontinent is restricted to the fringes of the Western Ghats, greater Assam region and some small places in Odisha. However, the palaeovegetation reconstruction in this study illustrates the existence of equatorial tropical forest in northwestern India (Bikaner, Rajasthan) during the early Eocene. Fossil leaves, described here, were collected from the Gurha lignite mine of Bikaner and showed affinities with Holigarna grahamii (Anacardiaceae), Pterygota alata (Malvaceae), Syzygium spp. (S. fruticosum and S. cumini) (Myrtaceae), and Gardenia spp. (G. lucida and G. gummiefra) (Rubiaceae). Contrary to the present-day dry and desertic conditions, the fossil records provide strong evidence of humid tropical and paratropical evergreen forest with monsoon seasonality existing in and around the study area during the depositional period. Any shift in climatic conditions has drastic effects on the vegetation cover of a region in time and space. This drastic change in climate has led to the extinction of tropical rain forest from this region. This might be due to the northward movement of the Indian subcontinent (away from the equator), formation of the Himalayas and monsoon or changes in monsoon pattern.

During the early Eocene (∼55–52 Ma), when the Indian subcontinent relished equatorial climatic conditions, lignite was deposited along its north western margin. Lignite mines of northwestern India have proved to be an outstanding resource for palaeoenvironmental information. The Vastan lignite mine of the early Eocene age situated near Surat district (Gujarat) is one of the well-dated and fossiliferous lignite mines in western India. A fossil wood, retrieved from this mine, is systematically described and shows a strong resemblance to the modern genus Chisocheton of the family Meliaceae. Plant fossils are the best source to reconstruct the palaeoenvironment of any region, and here a luxurious, highly diverse tropical evergreen forest is interpreted in and around the fossil locality in contrast to the tropical thorn forest of the present day. This early Eocene highly diverse equatorial forest, once covered a significant portion of the Indian subcontinent, is now restricted in fringes known as Western Ghats in south India attesting to changes in climate.

The systematics of a fossil wood assigned to Duabangoxylon (family Lythraceae) is described from the Deccan Intertrappean beds of Kutch, Gujarat, western India considered to be late Maastrichtian to early Danian in age. This fossil is the oldest record of Duabanga as its previous records are not older than Eocene. As the intertrappean flora of Kutch is poorly known, the present fossil not only enriches this flora but also helps in the reconstruction of palaeoclimate.

Monsoonal climates at low latitudes (< 32°N) are an inevitable consequence of seasonal migrations of the Inter-tropical Convergence Zone (ITCZ), but the character of these monsoons depends on continental configuration, orographic expression and the strength of Hadley circulation. To explore the evolution of monsoon systems across southern Asia we compare climate signatures archived in ten Paleogene floras from northern India, Tibet and southern China, occupying low palaeolatitudes at a time of extreme global warmth and elevated CO2. Fossil leaf form reveals that under such 'hothouse' conditions megathermal early Eocene to earliest Miocene forests were exposed to strong monsoonal climates typical of those experienced today arising from annual migrations of the ITCZ, possibly enhanced by a lower equator-to-pole temperature gradient. Throughout the Paleogene an elevated Tibetan highland produced no discernable modification of this ITCZ monsoon, although rainfall seasonality similar to that of the modern South Asia Monsoon (SAM) is observed in northern India as early as the beginning of the Eocene, despite its near-equatorial palaeoposition. In South China rainfall seasonality increased progressively achieving modern monsoon-like wet season/dry season precipitation ratios by the early Oligocene. Despite evidencing weak rainfall seasonality overall, fossil leaves from South China have exhibited monsoon-adapted morphologies, comparable to those seen in today's Indonesia-Australia Monsoon, for at least 45 million years. Together, the Indian and South China fossil leaf assemblages show that the evolution of megathermal ecosystems across southern Asia has been influenced profoundly by monsoonal climates for at least the last 56 million years. The Paleogene ITCZ-driven monsoon system strongly impacted India as it transited the Equator likely eliminating Gondwanan taxa not able to adapt to seasonal precipitation extremes. Furthermore, powerful seasonally-reversing winds, and associated surface ocean currents, are likely to have facilitated two-way biotic transfer between India and Eurasia long before closure of the Tethys Ocean.

Botryococcus, an important member of the planktonic algae, occurs in freshwater pools, lakes and occasionally in brackish-water lagoons, with wide distribution in tropical and temperate climate zones throughout the world. It is recognised as an oil-producing alga that is found in rock records from the Precambrian onwards. Here, this alga was retrieved from two different lignite mines of Rajasthan and Gujarat (western India), of early Eocene age. Apart from discussing its structural details, alterations in structures and preservation biases, this alga was used to reconstruct the depositional environment of the region based on its morphological and taphonomical characteristics. The images under transmitted light, fluorescence and scanning electron microscopy display aggregates of the irregular colonies, spherical to oval in shape, with cups arranged in definite patterns. The taphonomic characteristics of a large number of these algae indicate their autochthonous origin and in situ burial conditions. The dissolution of their outer layers suggests early diagenetic processes and loss of integrity due to microbial activity in the later phases of their burial in these sediments. The environment in the early Eocene has been reconstructed on the basis of the present findings, along with earlier recorded palynofacies from the region.

A 105 m early Eocene section exposed in the Gurha mine in the Nagaur-Ganganagar Basin, Rajasthan, India, archiving remains of equatorial vegetation at a time of extreme global warmth and close to the onset of the India-Eurasia collision, is investigated using palynostratigraphic and palynofacies analyses. Four palynozones e.g., Palmidites plicatus Singh, Botryococcus braunii Kützing, Triangulorites bellus Kar and Ovoidites ligneolus are identified stratigraphically on the basis of abundance of these pollen taxa over others. The occurrence of taxonomically highly diverse angiosperm pollen in all the four palynozones attests to an extremely rich near-coastal tropical flora subject to frequent wildfires under a strongly seasonal precipitation regime. Palynotaxa characteristic of these palynozones are widely distributed in other early Paleogene sediments of India. Sedimentary organic matter (structured terrestrial, biodegraded, amorphous, grey amorphous, resins, charcoal/black-brown debris and algal remains) recovered from mire and lacustrine sediments are of terrestrial origin, recording fluctuations in burial anoxia and salinity. Episodes of elevated salinity are due either to seepage of marine waters and/or a periodic excess of evaporation over precipitation at times when the depositional system was closed.

Thick lignite deposits on the western margin of India were preserved on account of thick vegetation which got buried underneath due to tectonic activities that occurred in northwestern part of India during the early Palaeogene. Study of the fossil flora preserved in these beds is important to deduce the palaeoclimate of the region. Therefore, a field work was undertaken to collect plant fossils from the Tarkeshwar lignite mine, Surat district, Gujarat (western India) which is still unexplored as far as the plant mega-remains are concerned. A fossil wood is systematically described from the Cambay Shale Formation of the mine considered to be of early Eocene in age. It shows close affinities with Holigarna (Anacardiaceae), particularly with H. beddomei and H. grahamii. This genus is evergreen in nature and grows in the Indo-Malayan region, while both the modern analogues of the fossil are endemic to semi-evergreen to evergreen forests ofWestern Ghats, south India, located at the equator. This not only confirms the palaeolatitudinal position of the Indian subcontinent at the equator during the early Palaeogene, but also indicates the presence of equatorial rain forest in the Indian subcontinent during the period. Based on the timetree, Sapindales started to diverge in the early Palaeocene (62–57 Ma) as its oldest fossil is from the K-Pg boundary. Discovery of the present anacardiaceous fossil (belonging to Sapindales) from the early Eocene strengthens the above phylogenetic view.

The Valia Lignite Mine situated near Bharuch (Gujarat) is poorly explored as far as the animal and plant remains are concerned. In order to explore the mine for building the palaeofloristics and reconstruction of the palaeoenvironment, a few wood pieces were collected from there. Subsurface beds of the early Eocene (Cambay Shale Formation) age are exposed in this open cast mine. A new fossil wood, Gynocardia eocenica sp. nov., of the Achariaceae is described for the first time from there. Gynocardia is monotypic and found in evergreen rain forests of northeast India, Bangladesh and Myanmar. The occurrence of present fossil indicates that the genus was originated in India during the early Eocene when the climatic conditions were warm and humid. Later on, it became extinct from western India due to the presence of arid to semiarid conditions and confined to northeast India having the equable climate.

Two new fossil woods resembling Eucalyptus L’ H’erit of the family Myrtaceae are described from the Palaeocene and Eocene successions of Gujarat and Rajasthan, respectively. They are characterized by diffuse-porous wood, heavily tylosed vessels arranged in echelon, vasicentic tracheids, simple perforations, thin rays and non septate fibres with bordered pits. Eucalyptus is considered native to Australia as most of its species are found there. The fossil records of Eucalyptus are hitherto known from the Cenozoic successions of Argentina, New Zealand, Australia and India. The genus is phytogeographically important as it has a wide range of distribution in the geologic past which suggests its long history affiliated with different Gondwanaland continents. A warm and humid coastal environment is inferred in western India during the Palaeogene on the basis of the earlier records of the genus.

A fossil fruit resembling extant Cocos nucifera of the family Arecaceae is reported for the first time from the early Eocene sediments of Gujarat. The fossil was collected from the Tarkeshwar lignite mine of the Surat District which belongs to the Cambay Shale Formation. Its occurrence indicates coastal conditions in the region during the depositional period in contrast to arid to semi-arid climate prevailing there at present. The present fossil, along with the previously published palyno-assemblages from the mine supports the equatorial position of the Indian subcontinent at the time of deposition i.e. during the early Eocene.

Early Eocene (~ 55–52 Ma) laminated lacustrine sediments overlying lignites in the Gurha Mine (27.87398°N, 72.86709°E), Rajasthan, India, yield a diversity of fossil leaves, flowers, fruits, seeds and insects. CLAMP (multivariate foliar physiognomic) analysis of two horizons separated by an estimated several tens of thousands of years of deposition indicates cool equatorial (~ 10°N) temperatures and a pronounced monsoon signature. A lower assemblage consisting of 54 leaf morphotypes and an upper assemblage of 57 leaf forms yielded mean annual temperatures (MAT) of 24.7 and 23.9 °C, respectively. The uncertainty (± 2.82 °C) means these temperature regimes are identical despite few similarities in the morphotypes between the two assemblages.The mean annual range of temperature (MART) was approximately 9.7 °C for both assemblages. When corrected for evapotranspirational cooling these temperature regimes are similar to those experienced today at 10°N on the west coast of India and surprisingly cool for the tropics at a time of extreme global warmth. Growth was year round. The tropical to paratropical fossil floras also suggest a moist regime (80% annual relative humidity) and high mean annual precipitation of ~ 1800 mm for both assemblages but with a pronounced wet/dry seasonality indicative of a pronounced monsoonal regime. The lower assemblage has a stronger monsoon index (11.8) than the upper assemblage (8.8). The two assemblages seem to have been deposited less than 100 ka apart. This suggests that not only a pronounced South Asian monsoon existed when India and Asia first made contact, but also a variation in monsoon strength existed that cannot be ascribed to tectonic drivers.

This study reports a new fossil leaf of Kleinhovia L., Kleinhovia bikanerensis sp. nov., from the Eocene clay mine of the Marh Formation of Bikaner, Rajasthan. The leaf resembling Kleinhovia hospita L. of the family Malvaceae is described for the first time from India. The leaf is characterized by very wide ovate shape, basal actinodromous venation with seven primary veins and cordate base. The presence of this leaf fossil indicates tropical warm and humid climatic conditions prevailing in the area during the Eocene and throws light on its past and present distribution.

The Kutch region of western India (Gujarat State) is today arid to semiarid and characterised by mostly ephemeral streams which carry water during the monsoon. The uneven distribution of rainfall and disturbed topography are the result of climate change during the Cenozoic period. Two fossil woods, namely Bauhinium palaeomalabaricum Prakash and Prasad (Fabaceae) and Ebenoxylon indicum Ghosh and Kazmi (Ebenaceae), are described from Kutch in order to provide insights into the palaeovegetation and palaeoclimate. Because the modern representatives of the present and previously described taxa from the same horizon are thermophilic in nature and grow in evergreen to deciduous forests, a warm and humid climate is interpreted. Furthermore, the finding of some mangrove taxa in the assemblage indicates the lagoonal to intertidal environment at the time of deposition.

A fossil wood of Lauraceae resembling those of the modern genera Cinnamomum Spreng. and Litsea Lam. is described from the Vagadkhol Formation of Bharuch District, Gujarat considered to be Palaeocene-Early Eocene in age. This is the first record of a fossil wood of this family from western India. In view of the meagre fossil records known from the Palaeogene sediments of western India, the present finding becomes important as it enriches the palaeofloristics. Its presence, along with the already described fossils indicates warm and humid conditions in the region during the depositional period in contrast to the present day dry climate.

Two fossil woods collected from the late Neogene sediments of Rajasthan show best resemblance to the modern genera Terminalia L. and Lagerstroemia L. of the families Combretaceae and Lythraceae, respectively. The fossils belong to the Shumar Formation of Jaisalmer Basin considered as Plio–Pleistocene in age. The habitats of the modern counterparts of the fossils indicate the prevalence of semi–evergreen to deciduous forests with warm and humid climatic conditions in the Jaisalmer District at the time of deposition of the sediments in contrast to the present day xeric vegetation with desertic conditions in the area.

Climate has played a crucial role in assigning a different kind of topography to Rajasthan and Gujarat since the Cenozoic time. Evidently, three genera, namely, Dipterocarpus Gaert. f., Hopea Roxb. and Shorea Roxb. of the Dipterocarpaceae are described from the Neogene sediments of western India (Rajasthan and Gujarat). These taxa are marked by their complete absence in the region today. The presence of Dipterocarpaceae in western India has been noticed from the Early Eocene up to the Plio-Pleistocene in deep time. The family is usually a dominant component of the humid tropical and subtropical flora of the Indo-Malayan region and its discovery, along with earlier described fossils from western India indicates existence of ancient tropical rain forests in western India. A change in the climate affected warm and humid conditions occurring there during the Cenozoic resulting in arid to semi-arid climate at present which is responsible for the ultimate extinction of Dipterocarpaceae in the region. In addition, the palaeobiogeography of Dipterocarpaceae is reviewed.

During the early Eocene, Rajasthan was positioned near the equator and had a warm and humid tropical climate dominated by tropical rainforests like the present-day equatorial forests of South India. Many of the plants retrieved as fossils from Rajasthan are growing there as refugee. This study further strengthens this view as it reports a new species of Uvaria L. from the early Eocene sediments of Bikaner (Rajasthan) showing its best resemblance with the extant U. zeylanica Deless. ex DC., which is presently growing in the evergreen forests of South India and Sri Lanka. The genus is thought to have originated in Africa, and the present finding gives an idea about its geologic distribution in Asia and Australasia via India relying on ‘stepping stone’ hypothesis during the Early Eocene Climatic Optimum (EECO) when climatic conditions were favourable for the luxuriant growth of tropical vegetation. A general cooling trend after EECO and change in the configuration of land and sea affected the climate on the ...

Shukla, A., Mehrotra, R.C. & Guleria, J.S. iFirst article. African elements (fossil woods) from the upper Cenozoic sediments of western India and their palaeoecological and phytogeographical significance. Alcheringa, 1–20. ISSN 0311-5518. Fossil woods resembling tropical African taxa are described from late Neogene–Pleistocene sediments of western India. They resemble the extant representatives of Baphia Afzel., Brachystegia Benth., Erythrophleum Afzel. (Fabaceae), Entandrophragma C. DC., Khaya A. Juss. (Meliaceae) and Milicia Sim (Moraceae). The discovery of these taxa indicates the invasion of African elements into the Indian subcontinent during the Plio-Pleistocene and palaeogeographic connections between the two continents. All these genera include both evergreen and deciduous representatives and grow mainly in the tropical forests of Africa. On this basis, the presence of semi-evergreen to deciduous forest is inferred in western India during the Neogene in contrast to the semi-arid to arid climate wi...

Eleven fossil woods belonging to seven families are described from a petrified wood forest of Mizoram. This fossil assemblage is derived from sediments belonging to the Tipam Group considered to be Late Miocene–Early Pliocene in age. The modern counterparts of the identified taxa are: Gluta L., Mangifera L. (Anacardiaceae), Bursera Jacq. ex L. (Burseraceae), Terminalia L. (Combretaceae), Shorea Roxb. (Dipterocarpaceae), Cynometra Linn., Dalbergia L. f., Millettia Wight et Arn.–Pongamia Vent, Ormosia Jacks. (Fabaceae), Artocarpus Forst. (Moraceae) and Madhuca Gmelin. (Sapotaceae). The genus Dalbergia is described for the first time from India. The modern environmental tolerances of the above taxa indicate the existence of a tropical warm and humid climate in Mizoram during the depositional period. The reconstructed climate data using Coexistence Approach (CoA) based on palaeoflora database of Mosbrugger and Utescher, along with other published data sets indicates an MAT (mean annual temperature) of 26.1–27.7 °C, a mean temperature of the warmest month (WMT) of 25.4–28.1 °C, a mean temperature of the coldest month (CMT) of 25.6–26 °C, and a mean annual precipitation (MAP) of 3180–3263 mm. These climatic interpretations are congruent with the data obtained from the anatomical features of all the fossil taxa. As all the fossil taxa possess diffuse porous wood, they further indicate a tropical climate with little seasonality. The majority of the taxa in the fossil assemblage generally have large vessels and simple perforation plates which indicate high precipitation. The present study provides vital evidence of floral exchange or migration between India and southeast Asia.

The Gondwanan origin, northward migration and subsequent collision with Asia means that the Indian subcontinent is of particular interest regarding the origin and dispersal of numerous plants and animal species. With this in mind, we describe a fossil leaf of Aporosa Blume (Phyllanthaceae) from the Paleogene of the Indian subcontinent and discuss its evolution and diversification with respect to the moving Indian plate and its connection with Southeast Asia since the early Cenozoic. At present, Aporosa Blume is confined to Southeast Asia with a few species in India and New Guinea. It is represented by six endemic species growing in the evergreen forests of India and Sri Lanka, including Aporosa acuminata Thwaites, which is morphologically close to the here described fossil from Bikaner, Rajasthan, India. From the age of the fossil and the distribution of its modern comparable form, it is assumed that Aporosa originated on the Indian subcontinent and then was distributed to Southeast Asia, supporting the ‘Out of India’ hypothesis. Diversification of the genus might have taken place either in the Paleogene or Neogene. Our fossil leaf material also indicates the existence of palaeoequatorial (< 10° N) tropical rain forests in western India during the Paleogene in contrast to dry and desertic climate occurring today.

A new fossil fruit wing of Shorea Roxb. belonging to the family Dipterocarpaceae is described from the Early Miocene sediments of Kachchh, Gujarat. It resembles best the extant species Shorea macroptera Dyer, which is a prominent member of the tropical evergreen forests of the Malayan Peninsula. The present finding, along with the other megafossil records described from the same area, indicates a typical tropical vegetation with a warm and humid climate at the time of deposition in contrast to the present day xeric vegetation in the area. As the family Dipterocarpaceae no longer exists in western India, it is essential to discuss the time of its extinction and possible causes, which may include drastic changes in the climate of the region. The present finding also supports the theory of a Malaysian origin for the family in contrast to the hypothesis of a Gondwanan origin.

The paper describes two gymnospermous woods, namely Araucarioxylon Kraus, 1870 and Podocarpoxylon Gothan, 1905 from the Late Cenozoic sediments (Shumar Formation) of district Jaisalmer, Rajasthan, western India. The woods indicate favourable climatic conditions for the growth of mesic vegetation in Rajasthan till Plio-Pleistocene time compared to the xeric vegetation and drier conditions in the area today.

The Vastan Lignite Mine, situated about 30 km northeast of Surat in Gujarat, preserves a fairly continuous record of near shore lignites interbedded with lagoonal and open marine sediments bearing foraminifera and molluscs. This paper reports a teredo-infested fossil dicotyledonous wood belonging to Family Meliaceae from the carbonaceous shale sequence near the top of the Lower Eocene section. The wood is well preserved and shows resemblance with the extant woods of the genus Aglaia Lour. The presence of wood suggests a fluvial transport from its natural habitat of an inland moist tropical forest to a nearby coastal region. The profuse infestation of the wood by teredos further indicates considerable exposure before burial probably in a near shore lagoon or tidal flat area where it was bored by Teredolites.

Cocos sahnii Kaul, a fossil palm fruit, is validated and described from the Fuller’s earth deposits of Kapurdi village of Rajasthan considered as Early Eocene in age. The fossil best resembles the genus Cocos, particularly Cocos nucifera L., which is now a common coastal element thriving in highly moist conditions. The recovery of this coconut-like fruit, along with earlier described evergreen taxa from the same formation, suggests the existence of typical tropical, warm and humid coastal conditions during the depositional period. The present arid to semi-arid climatic conditions occurring in Rajasthan indicate drastic climate change in the region during the Cenozoic. The possible time for the onset of aridity in the region which caused the total eradication of semi-evergreen to evergreen forests is discussed, as well as the palaeobiogeography of coconuts.