A permineralized species of mangrove fern Acrostichum L. from Deccan Intertrappean beds of India

Acrostichum intertrappeum sp. nov., a permineralized aerial stem with helically arranged petioles and roots in organic connection, is described from the Deccan Intertrappean beds of Nawargaon, District Wardha, Maharashtra, India and forms the first and the oldest record of its kind. The stem is covered with a thick ramentum of large multicellular scales and is characterized by a three angled dictyostele enclosing a few medullary bundles. The petioles are helically arranged and the vascular morphology is distinct with abaxial horseshoe-shaped ring, adaxial linear row and central dorso-ventrally elongated ring. The roots have hexarch steles and aerenchymatous cortex with large air cavities in rings. Occurrence of Acrostichum along with coastal palms, mangroves and marsh plants described earlier from this region and nearby locations suggests the north-western shore of the Deccan was linked to the equatorial ocean (South Western Tethys Sea) probably through the Narmada Valley during the deposition of Intertrappean sediments. Morphological features and anatomical characters of the fossil reveal that Acrostichum grew in marsh swamp environment or on mud flats of back water areas of the coastal environment prevailing a tropical humid climate when the Deccan region was almost at an equatorial position during the Late Cretaceous period. This new record further adds to a growing body of data on the diversification of polypodiaceous ferns that point to a much earlier crown group radiation of the group than previously thought.     

Oldest known non-marine diatoms (Aulacoseira) from the uppermost Cretaceous Deccan Intertrappean beds and Lameta Formation of India

Non-marine diatoms occur in the Deccan Intertrappean beds (Upper Cretaceous) of Mohgaon-Kalan, Chhindwara District, Madhya Pradesh and Pisdura, Lameta Formation (Upper Cretaceous), Maharashtra, India. This represents the oldest record of non-marine diatoms yet reported and the oldest from the Indian subcontinent. The diatoms were recovered from thin sections of chert and dinosaur coprolites by random fracturing. Solitary forms are the most common but colonial filaments up to five cells were also observed. Based on the morphological characters, the diatoms are identified as Aulacoseira Thwaites. The Lower Cretaceous marine diatom genus Archepyrgus Gersonde and Harwood also resembles Aulacoseira in general morphological characters and it seems that Aulacoseira evolved from Archepyrgus and migrated to the non-marine realm.     

Conifer Woods of the Pliocene Age from Yunnan, China

The Tertiary floras play an integral role in understanding the biodiversity and interactions between climate and vegetation in Yunnan, China. The fossil spores, pollen grains, and leaves in this region have been investiaged intensively. In comparison, the woods have been studied relatively little. A large number of Pliocene wood specimens was collected from the opencast lignite coal mine of Hongxing situated in Changning County of Yunnan Province. Among the collection, Tsuga cf. dumosa (D. Don) Eichler and Pinus cf. armandii Franchet were identified based on wood structures. The subtle feature oftori extensions is reported in the wood of T. cf. dumosa. Considering the climatic requirements of modern T. dumosa and P.armandii, the two species of conifer described from Pliocene sediments probably grew in mountainous terrain at an elevation of approximately 2 300 m, in a cool and humid environment.     

Conifer Woods of the Pliocene Age from Yunnan, China

The Tertiary floras play an integral role in understanding the biodiversity and interactions between climate and vegetation in Yunnan, China. The fossil spores, pollen grains, and leaves in this region have been investiagedintensively. In comparison, the woods have been studied relatively little. A large number of Pliocene wood specimens was collected from the opencast lignite coal mine of Hongxing situated in Changning County of Yunnan Province. Among the collection, Tsuga cf. dumosa (D. Don) Eichler and Pinus cf. armandii Franchet were identified based on wood structures. The subtle feature of tori extensions is reported in the wood of T. cf. dumosa. Considering the climatic requirements of modern T. dumosa and P.armandii, the two species of conifer described from Pliocene sediments probably grew in mountainous terrain at an elevation of approximately 2 300 m, in a cool and humid environment.     

Palaeobiogeographic significance of the Deccan infra‐ and intertrappean biota from peninsular India

Extensive work done in the last decade on the sedimentary beds intercalated with the Deccan volcanic flows (infra‐ and intertrappean) has demonstrated the vast potential of these rocks for vertebrate, invertebrate and plant fossils. The infra‐ and intertrappean beds, especially those exposed on the eastern margin of the Deccan Traps, produced a large number of fossils which made it possible to establish the age and duration of Deccan volcanism (late Cretaceous—early Palaeocene) with some degree of confidence. Affinities of the late Cretaceous infratrappean vertebrates, such as pelomedusid turtles and sauropod dinosaurs, lie with those of Gondwanan landmasses. It seems more likely that these taxa are relicts of the Gondwanan stock that boarded the Indian plate well before its separation from Madagascar 70–80 Ma ago. Remnants of the former Gondwanaland fauna, such as pelomedusid turtles, leptodactylid frogs and titanosaurid dinosaurs did persist in relatively younger (latest Cretaceous) intertrappean beds. In addition to these Gondwanan elements, the intertrappean beds register many North American, European and Central Asiatic taxa (pelobatid and discoglossid frogs, anguid lizards, alligatorid crocodiles, palaeoryctid mammals, ostracodes and charophytes) suggesting that a contact between India and southern Asia was already established by the end of Cretaceous. An early India/Asia collision, long before the widely accepted early to middle Eocene date, is favoured to explain the presence of Laurasian elements in the late Cretaceous of India.     

Paleoenvironmental and paleobiogeographical implications of the microfossil assemblage from the Late Cretaceous intertrappean beds of the Manawar area,District Dhar,Madhya Pradesh,Central India

Abstract

An assemblage of microfossils consisting of non-marine ostracods (Cypridopsis, Gomphocythere, Zonocypris, Eucypris, and Frambocythere), charophyte gyrogonites (Platychara), molluscs (Viviparus, Valvata, and Lymnaea), and fish remains (mainly Phareodus), is here reported from a new intertrappean locality near the town of Manawar, District Dhar, Madhya Pradesh, Central India. The biotic component recovered suggests a Late Cretaceous (Maastrichtian) age for the intertrappean deposit near Manawar. Paleoenvironmentally, the overall biotic assemblage recovered indicates the presence of a freshwater palustrine/lacustrine depositional system connected to a low energy stream/river. Paleobiogeographically, the known high diversity of ostracod genera, especially Eucypris, Cypridopsis, and Gomphocythere, hints at endemism within the Indian Subcontinent during the Late Cretaceous (Maastrichtian). However, the cosmopolitan distribution of the charophyte genus Platychara in the K-Pg interval across the globe (Africa, Europe, and America) and its absence in the Upper Cretaceous of China and Mongolia is quite intriguing.     

Comparative floral structure and systematics in Rhizophoraceae,Erythroxylaceae and the potentially related Ctenolophonaceae,Linaceae, Irvingiaceae and Caryocaraceae (Malpighiales)

Within the rosid order Malpighiales, Rhizophoraceae and Erythroxylaceae (1) are strongly supported as sisters in molecular phylogenetic studies and possibly form a clade with either Ctenolophonaceae (2) or with Linaceae, Irvingiaceae and Caryocaraceae (less well supported) (3). In order to assess the validity of these relationships from a floral structural point of view, these families are comparatively studied for the first time in terms of their floral morphology, anatomy and histology. Overall floral structure reflects the molecular results quite well and Rhizophoraceae and Erythroxylaceae are well supported as closely related. Ctenolophonaceae share some unusual floral features (potential synapomorphies) with Rhizophoraceae and Erythroxylaceae. In contrast, Linaceae, Irvingiaceae and Caryocaraceae are not clearly supported as a clade, or as closely related to Rhizophoraceae and Erythroxylaceae, as their shared features are probably mainly symplesiomorphies at the level of Malpighiales or a (still undefined) larger subclade of Malpighales, rather than synapomorphies. Rhizophoraceae and Erythroxylaceae share (among other features) conduplicate petals enwrapping stamens in bud, antepetalous stamens longer than antesepalous ones, a nectariferous androecial tube with attachment of the two stamen whorls at different positions: one whorl on the rim, the other below the rim of the tube, the ovary shortly and abruptly dorsally bulged and the presence of a layer of idioblasts (laticifers?) in the sepals and ovaries. Ctenolophonaceae share with Rhizophoraceae and/or Erythroxylaceae (among other features) sepals with less than three vascular traces, a short androgynophore, an ovary septum thin and severed or completely disintegrating during development, leading to a developmentally secondarily unilocular ovary, a zigzag‐shaped micropyle and seeds with an aril. Special features occurring in families of all three groupings studied here are, for example, synsepaly, petals not retarded and thus forming protective organs in floral bud, petals postgenitally fused or hooked together in bud, androecial tube and petals fusing above floral base, androecial corona, apocarpous unifacial styles, nucellus thin and long, early disintegrating (before embryo sac is mature), and nectaries on the androecial tube. Some of these features may be synapomorphies for the entire group, if it forms a supported clade in future molecular studies, or for subgroups thereof. Others may be plesiomorphies, as they also occur in other Malpighiales or also in Celastrales or Oxalidales (COM clade). The occurrence of these features within the COM clade is also discussed. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 166 , 331–416.     

Palynoflora from intertrappean localities in southeastern part of Deccan volcanic province: taxonomic composition,age and paleogeographic implications

Understanding the flora preserved in the Late Cretaceous–Early Paleocene Deccan volcanic associated sediments is significant as it gives insight into the floral composition during Deccan volcanic activity. This time interval is also associated with extinction and evolution of many angiosperm families on the Indian subcontinent. The record of palynomorph bearing intertrappean beds of Shankar Lodhi in Chandrapur district and Shimbala in Yavatmal district of Maharashtra from southeastern part of Deccan volcanic province provides information on biodiversity, age and depositional environment of the Deccan province. These intertrappean beds are characterized by presence of Maastrichtian age marker taxa such as Azolla cretacea, Jiangsupollis and Echitricolpites. Aquatic palynoassemblage such as, Azolla cretacea, Crybelosporites intertrappea, Gabonisporis vigourouxii and Sparganiaceaepollenites are dominant in Shankar Lodhi intertrappean beds. Presence of taxa Crybelosporites, Incrotonipollis and Periporopollenites in the intertrappean beds of the study area and their global geological history suggest their Gondwanan origin.     

Fossil wood of the Juglandaceae: Some questions of taxonomy,evolution, and phylogeny in the family based on wood anatomy

Some problems in the taxonomy of the Juglandaceae are discussed based on wood anatomy; the identification of fossil juglandaceous wood is considered. Data on fossil wood of the Juglandaceae are summarized; a key for identification of wood anatomy in modern and fossil Juglandaceae is compiled. Wood anatomical characters in members of the family are discussed in the light of major evolutionary trends in the secondary xylem of dicots, and a comparative characterization of members of the family is developed. A hypothesis is proposed that the subfamily Engelhardioideae is the most primitive member of the Juglandaceae based on wood anatomy, the tribe Juglandeae and subfamily Platycaryoideae are slightly more highly specialized, and the tribe Hicorieae is the most advanced. Evolutionary relationships between the members of the Juglandaceae are reviewed based on wood anatomy.     

Freshwater fish otoliths from the Deccan Trap associated sedimentary (Cretaceous-Tertiary transition) beds of Rangapur,Hyderabad, District,Andhra Pradesh,India

The present paper describes 12 species of fish otoliths recovered by washing and screening processes from the Deccan Trap associated sedimentary (Intertrappean) beds exposed near Rangapur, Hyderabad District, Andhra Pradesh, India. The present collection of otoliths contains four major groups: Clupeomorpha (“Clupeidarum” sp.), Osteoglossomorpha (“Osteoglossidarum” deccanensis sp. nov., “O”. intertrappus sp. nov. and “Notopteridarum” nolfi sp. nov.), Protacanthopterygii (“Salmoniformorum” rectangulus sp. nov.), and Percomorpha (Dapalis sp., “Apigonidarum” ovatus sp. nov., “Serranidarum” sp., “Percoideorum” ellipticus sp. nov., “P.” rangapurensis sp. nov., “Percoideorum” sp. 1 and “Percoideorum” sp. 2). This collection of otoliths represents freshwater lacustrine deposition of the sediments. The age of the Intertrappean beds is considered Uppermost Cretaceous to Palaeoncene on the basis of freshwater ostracode (Paracypretta jonesi, Mongolianella hislopi and Candoniella sp.) and charophyte (Platychara perlata and Nemegtichara sp.) assemblages.     

Paleobiota from the Deccan volcano-sedimentary sequences of India: paleoenvironments,age and paleobiogeographic implications

Paleobiotic assemblages from the Deccan infra- and intertrappean beds are reviewed in great detail. Three distinct paleoenvironments (fluvio-lacustrine/terrestrial, brackish water and marine) have been identified within the infra- and intertrappean biotic assemblages of peninsular India. Recently, marine incursions have been recorded in a few of the Deccan intertrappean beds exposed in central and south-eastern India. The intertrappean beds have yielded marine planktic foraminiferans and freshwater/brackish water ostracods. The affinities of the paleobiotas are commonly considered to show a mixed pattern resulting from the addition of Gondwanan and Laurasian elements to endemic Indian taxa. During the last four decades, various biogeographic models (southern and northern connections) have been proposed to explain the presence of anomalous biogeographic biota in the Late Cretaceous of India. Based on the recovered fauna and flora assemblages, the Cretaceous–Paleogene boundary has been marked and a Late Cretaceous to Early Paleocene age has been assigned to these Deccan volcano-sedimentary sequences.     

A comparison of the wood anatomy of 11 species from two cerrado habitats (cerrado s.s. and adjacent gallery forest)

A comparative study of the secondary xylem (wood) anatomy of 11 species (38 specimens) occurring in cerrado s.s. and the adjacent gallery forest (both cerrado s.l. habitat) was made with the aim of identifying the anatomical characteristics of ecological value and correlating them with the environmental conditions. The anatomical features that vary, in general, between the two habitats are: growth ring distinctness (well or poorly defined); tyloses and deposits (more abundant in cerrado specimens); gelatinous fibres (more evident in cerrado specimens and in different patterns between habitats); variation in paratracheal and banded parenchyma (more abundant in cerrado); and more cells per parenchyma strand in cerrado. In general, gallery forest specimens have wider vessels, fewer vessels per square millimetre and larger intervessel pits, indicating more efficient water conduction, whereas cerrado s.s. specimens are the opposite, with low vulnerability and mesomorphy indices, demonstrating greater safety under conditions of water stress. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, ?? , ??–??.     

Fossil coniferous wood from the Middle Jurassic of Liaoning Province, China

Silicified coniferous wood was collected from the Lanqi Formation (late Middle Jurassic in age) at Shebudaigou Village, Liaoning Province, China. Three taxa are identified, namely Pinoxylon dacotense Knowlton, Xenoxylon phyllocladoides Gothan, and Araucariopitys sp. Based on these new data, and those of other fossil plants reported previously from the same formation, we consider the climate during the deposition of the Lanqi Formation was subtropical, humid and seasonal. In this respect the Lanqi flora differs from the coeval Shimengou and Longmen floras from North China. The Longmen flora was deposited during more humid, subtropical conditions, while the Shimengou Formation indicates that the climate was warm temperate and dry. Our data would suggest that the Late Jurassic climatic pattern was initiated as early as the late Middle Jurassic.     

Bordered pits in ray cells and axial parenchyma: the histology of conduction, storage, and strength in living wood cells

Bordered pits occur in walls of living ray cells of numerous species of woody dicotyledons. The occurrence of this feature has been minimally reported because the pits are relatively small and not easily observed in face view. Bordered pits are illustrated in sectional view with light microscopy and with scanning electron microscopy in face view for dicotyledonous and gnetalean woods. Bordered pits are more numerous and often have prominent borders on tangential walls of procumbent ray cells, but also occur on radial walls; they are approximately equally abundant on tangential and horizontal walls of upright cells, suggesting parallels to cell shape in flow pathway design. Axial parenchyma typically has secondary walls thinner than those of ray cells, but bordered pits or large simple pit areas occur on some cross walls of parenchyma strands. There is no apparent correlation between the phylogenetic position of species and the presence of borders in ray cells or axial parenchyma. Bordered pits represent a compromise between maximal mechanical strength and maximal conductive capability. High rates of flow of sugar solutions may occur if starch in ray cells or axial parenchyma is mobilized for sudden osmotic enhancement of the conductive stream or for rapid development of foliage, flowers, or fruits. Measurement of the secondary wall thickness of ray cells may offer simple inferential information about the role that rays play in the mechanical strength of woods. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 157–168.     

Wood anatomy of Penaeaceae (Myrtales): comparative, phylogenetic, and ecological implications

Wood samples of stems, lignotubers, and roots of the majority of species of Penaeaceae were analyzed with respect to qualitative and quantitative features. Virtually no data have hitherto been presented on xylem features of this family, restricted to Cape Province, South Africa. Presence of vestured pits in vessels, septate crystalliferous parenchyma in wood, intraxylary phloem, predominantly erect ray cells in the typically narrow, multiseriate rays and in the uniseriate rays, and amorphous deposits in ray cells place Penaeaceae securely in Myrtales and help to define that order. By comparison of ecological preferences of the species, as observed during field work, with quantitative analysis of conductive tissue, close correspondence of the wood structure to habit and habitat is demonstrated.     

Amphibians and squamates from the Neogene Siwalik beds of Jammu and Kashmir, India

The Neogene Siwalik deposits of Jammu Province (India) have yielded amphibians and squamates. The collection includes the first amphibians and the first colubroid snakes from the Siwalik Group. Amphibians comprise only anurans: a possible Ranidae and one, or perhaps two, non-ranid frogs Squamates include one lizard,Varanus sp. (Varanidae), whereas snakes are represented by three taxa:Acrochordus dehmi (Acrochordidae), an indeterminate Colubridae, and a snake that is either a Colubridae or an Elapidae.Varanus sp. andA. dehmi have been yielded by the Upper Miocene Ramnagar Member, whereas the anurans and colubroid snakes come from the Upper Pliocene Labli Member. These taxa are indicative of aquatic palaeoenvironment.     

Elevated atmospheric CO2 alters wood production, wood quality and wood strength of Scots pine (Pinus sylvestris L) after three years of enrichment

Scots pine ( Pinus sylvestris L.) trees were grown in open top chambers for three years under ambient and elevated CO₂ concentrations. The trees were aged 3 y at the beginning of the CO₂ exposure, and the effects of the treatment on total stem volume, stem wood biomass, wood quality and wood anatomy were examined at the end of the exposure. The elevated CO₂ treatment lead to a 49% and 38% increase in stem biomass and stem wood volume, respectively. However, no significant effects of the elevated CO₂ treatment on wood density were observed, neither when green wood density was estimated from stem biomass and stem volume, nor when oven-dry wood density was measured on small wood samples. Under elevated CO₂ significantly wider growth rings were observed. The effect of elevated CO₂ on growth ring width was primarily the result of an increase in earlywood width. Wood compression strength decreased under elevated CO₂ conditions, which could be explained by significantly larger tracheids and the increased earlywood band, that has thinner walls and larger cavities. A significant decrease of the number of resin canals in the third growth ring was observed under the elevated treatment; this might indicate that trees produced and contained less resin, which has implications for disease and pest resistance. So, although wood volume yield in Scots pine increased significantly with elevated CO₂ after three years of treatment, wood density remained unchanged, while wood strength decreased. Whilst wood volume and stem biomass production may increase in this major boreal forest tree species, wood quality and resin production might decrease under future elevated CO₂ conditions.     

Palaeoginkgoxylon zhoui, a new ginkgophyte wood from the Guadalupian (Permian) of China and its evolutionary implications

A new taxon of ginkgophyte affinity Palaeoginkgoxylon zhoui gen. nov. et sp. nov. is described from the Guadalupian Lower Shihhotse Formation of the Hulstai coalfield, Inner Mongolia Autonomous Region (Nei Mongol), northern China, on the basis of the anatomical structures of the broad eustele and pycnoxylic secondary xylem. The anatomical structure of the new woody tree trunk resembles both the early gymnosperms of Eristophyton-Pitus types and the modern Ginkgo. Therefore, the new tree trunk is interpreted as representing a transitional stage in the evolution of Ginkgo from early arborescent lignophytes since the Early Carboniferous.     

The first record of fossil Vitaceae wood from the Southern Hemisphere,a new combination for Vitaceoxylon ramunculiformis,and reappraisal of the fossil record of the grape family (Vitaceae) from the Cenozoic of Australia

Austrovideira dettmannaegen. & sp. nov. from the early Oligocene Capella Flora in central Queensland is the first fossil Vitaceae wood described from the Southern Hemisphere. A new combination, Stafylioxylon ramunculiformis (Poole & Wilkinson) Pace & Rozefelds for a Northern Hemisphere fossil wood is also proposed. Austrovideira and Stafylioxylon share with Vitaceoxylon secondary xylem with two diameter classes of vessels, wide vessels usually solitary, narrow vessels forming radial chains, very wide and tall rays, scanty paratracheal parenchyma and septate fibres. Austrovideira differs from Vitaceoxylon in having scalariform intervessel pits and homocellular rays composed exclusively of procumbent cells. This combination of features is seen in the Ampelocissus‐Vitis clade, and a clearly stratified phloem with fibre bands alternating with all other axial elements and phloem rays rapidly dilating towards the periderm is restricted to Parthenocissus and Vitis. Stafylioxylon shares with Austrovideira the presence of scalariform intervessel pits but it differs from that genus in both ray composition and bark anatomy, as it lacks a stratified phloem. These fossil wood genera demonstrate that the lianescent habit in the Vitaceae was established by the Eocene in the Northern Hemisphere and by the Oligocene in the Southern Hemisphere. The pollen and seed fossil record shows that the Vitaceae were in Australia by the Eocene and fossil seeds suggest that the family had radiated by this time. The Oligocene Capella flora with two seed taxa and fossil wood (Austrovideira) provides further evidence of an Australian radiation. The fossil evidence, suggests a significant Gondwanic history for the family.