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The plant fossil record of Bhavnagar is poorly documented despite its importance in understanding the evolution of Asian monsoonal ecosystems through time. Three genera of the families Fabaceae and Combretaceae are described from the Gaj Formation of Saurashtra Basin, Gujarat. The sediments of this formation are exposed around Lakhanka-Mithi Virdi villages in the Bhavnagar district of Gujarat and considered of early to middle Miocene in age. This is the first plant fossil record from the region of this age. The described fossil woods i.e. Hopeoxylon speciosum (Navale) Awasthi, Millettioxylon palaeopulchra Lakhanpal et al., and Terminalia tomentosa Wight and Arn. are found similar to the modern genera Sindora Miq., Millettia Wight & Arn (Fabaceae) and Terminalia L. (Combretaceae), respectively. The present distribution of modern comparable forms of the fossil taxa suggests existence of tropical to subtropical forests and warm and humid climatic conditions in the region during the Miocene in contrast to the sub-humid to dry climate seen today. [ABSTRACT FROM AUTHOR]

Premise: Ficus is a scientifically and economically important genus with abundant fossil records from the Paleocene to Pleistocene, but with an intriguing early evolutionary history that remains unresolved. Here, the foliage of three well‐preserved figs is described from the early Paleogene succession of the Gurha mine, Rajasthan, India. These fossils provide new morphological data that strengthens our understanding of the past occurrences of Ficus and, alongside all validly published records of fossil figs, helps to trace the evolutionary history of figs. Methods: Fossils were identified and described by comparison with their closest modern analogs using the Nearest Living Relative (NLR) technique. Validated fig records are listed and categorized into six geological time frames. Modern precipitation data for the current distributions of NLRs were downloaded from the Climatic Research Unit Timeseries. Results: Fossil leaves assigned to three new species Ficus paleodicranostyla, F. paleovariegata, and F. paleoauriculata closely resemble their modern analogs based on leaf morphology. Reliable fossil records were used to hypothesize historical fig distributions and paleodispersal pathways. Precipitation data suggest higher precipitations at the fossil locality during the early Paleogene than at present. Conclusions: The fossils described herein supplement fig fossil records known from other regions indicating that figs were widely diverse across low latitudes by the early Paleogene. These data support a Eurasian origin for figs, highlight a pivotal role for the Indian subcontinent during the early phase of fig diversification, and depict a perhumid‐to‐humid climate with high rainfall concordant with paleoclimate evidence from the Gurha mine. [ABSTRACT FROM AUTHOR]

Meliaceae is an important angiosperm family having floristic and ecological significance in major biomes, especially in tropical rainforests. Well preserved leaflet and pollen comparable to the extant genus Swietenia of the Meliaceae from the late Paleocene-early Eocene sedimentary horizon of the Gurha lignite mine, Rajasthan (western India) are described. The genus Swietenia (usually called mahogany) has scarce and fragmentary fossil records, and its evolutionary and paleobiogeographic history is partly understood. The fossil leaflet is characterized by an asymmetrical microphyll-sized lamina with an entire margin, festooned brochidodromous venation, mainly mixed percurrent tertiary and freely ramified quaternary veins, whereas the fossil pollen grains have a tetra-colporate aperture, relatively short colpi, alolongate pore, and a thick and laevigate exine with pitted to psilate ornamentation. These early Paleogene fossils are the oldest known fossil records of the genus Swietenia and add a new perspective to its paleobiogeographic distribution in Southeast Asia during the early Paleogene and this study would encourage future research endeavors to elucidate the evolution and diversification of the economically important group encompassing the genus Swietenia. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Today, Northeastern India receives some of the highest annual rainfall totals globally. The major portion of annual precipitation in this region falls during the Indian Summer Monsoon season (June–September); however, this region also receives a significant amount of rainfall during the pre-monsoon season (March–May). Here, we quantitatively reconstruct the climate of the Upper Siwalik subgroup, eastern Himalayan region, based on fossil assemblages using the Coexistence Approach (CA). The age of the fossil assemblage is considered to be late Pliocene–early Pleistocene. Data reconstructed for the present-day and past pre-monsoon rainfall in Northeastern India indicate an increasing trend since the late Miocene–early Pliocene. During the late Pliocene–early Pleistocene (Upper Siwalik), the temperature seasonality between warm (27–28.1 °C) and cold months (22–23.6 °C) was less pronounced compared with present-day warm (27–27.7 °C) and cold (14.8–15.4 °C) months conditions at the fossil locality. The reconstructed rainfall data indicate a monsoonal type of climate having a strong seasonality in wet and dry seasons during the deposition of the Upper Siwalik sediments. Moreover, composition of the fossil floras and reconstructed palaeoclimate suggest a vegetation shift from dominantly wet evergreen to semi-evergreen at the fossil locality, coincident with an increase in length of the dry season. The comparison of reconstructed CA data and climate modelling data of a Gelasian time slice with that of previously reconstructed climate data by using Climate Leaf Analysis Multivariate Programme (CLAMP) analysis of the late Pliocene–early Pleistocene (Upper Siwalik) fossils of the same locality provides nearly the identical result. Furthermore, all the reconstructed data indicate a monsoonal type of climate during the deposition of the Upper Siwalik sediments. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A fossil wood of Lagerstroemia L. from the Upper Siwalik sediments of Arunachal Pradesh is described. The genus is recorded for the first time from this state. The modern analog of the fossil species i.e. L. tomentosa C. Presl is not found in the fossil locality at present.. The most plausible reason for the disappearance of the species from the fossil locality is an increase in temperature seasonality caused by the upheaval of the Himalaya during the Pleistocene. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Fossil wood was collected from an in situ upright tree encased in the late Oligocene mudstone sediments exposed in the Tirap Mine, Makum Coalfield, Tinsukia district, Assam. The wood belongs to Careya of the Lecythidaceae. This genus is reported for the first time from Paleogene sediments. Its presence supports the occurrence of tropical evergreen to deciduous forests in the region during the depositional period. [ABSTRACT FROM AUTHOR]

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, namelyBauhinium palaeomalabaricumPrakash and Prasad (Fabaceae) andEbenoxylon indicumGhosh 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. [ABSTRACT FROM AUTHOR]

Reactions of bis(β-diketonato)aluminium(III)-di-μ-isopropoxo-di-isopropoxoaluminium(III), [(CH3COCHCOR)2Al-(μ-OPr-i)2Al(OPr-i)2] with 2-pyridylmethanol, (C5H4N-2-CH2OH) in 1:1 and 1:2 molar ratios in refluxing anhydrous benzene resulted in the synthesis of [(CH3COCHCOR)2Al(μ-OPr-i)2Al(OCH2-2-C5H4N)(OPr-i)] [where R=CH3 (1), -OC2-H5 (3), and -C6H5 (5)] and [(CH3COCHCOR)2Al(μ-OPr-i)2Al(OCH2-2-C5H4N)2] [where R=CH3 (2), -OC2H5 (4), and -C6H5 (6)], respectively. All of these compounds are sharp melting solids and are soluble in a variety of organic solvents (e.g., benzene, chloroform and dimethyl sulfoxide) except [(CH3COCHCOOC2H5)2Al(μ-OPr-i)2Al(OCH2-2-C5H4N)2], which is insoluble in benzene but soluble in chloroform and dimethylsulfoxide. All of these derivatives show a dinuclear structure in benzene. All of the above derivatives have been characterized by elemental analyses, molecular weight determinations, IR and NMR (1H, 13C and 27Al) and FAB mass spectral studies. [ABSTRACT FROM AUTHOR]

Reactions of bis (β-diketonato) aluminium(III)-di-μ-isopropoxo-di-isopropoxo-aluminium (III), [CH 3 COCHCOR) 2 Al(μ-OPr i ) 2 Al(OPr i ) 2 ], with triphenylsilanol, Ph 3 SiOH, in 1∶1 and 1∶2 molar ratios and with diphenylsilanediol, Ph 2 Si(OH) 2 , in a 1∶1 molar ratio, have resulted in the synthesis of [(CH 3 COCHCOR) 2 Al(μ-OPr i ) 2 Al(OSiPh 3 )(OPr i )], [(CH 3 COCHCOR) 2 Al(μ-OPr i ) 2 Al(OSiPh 3 ) 2 ] and [(CH 3 COCHCOR) 2 Al(μ-OPr i ) 2 ], respectively. These are soluble in a variety of organic solvents ( e.g. , benzene, chloroform and dimethylsulfoxide) and show dinuclear behaviour in chloroform. These derivatives have been characterized by elemental analyses, molecular weight measurements, IR and NMR ( 1 H, 13 C and 27 Al) studies. [ABSTRACT FROM AUTHOR]