Limits of stratigraphic distribution of Glossopteris in India: Discussion

The stratigraphic limits of Glossopteris in India have been reviewed by Sarbadhikari (1974) and are inferred to range from the Sakmarian-Artinskian (early Permian) to the Permo-Triassic transition. The lower limit in peninsular India is revised as Asselian with the help of Eurydesma-dominated fauna. Glossopteris was well established during the Asselian in the Salt Range but appeared during the late Sakmarian-Artinskian in the Himalayas. In peninsular India, Glossopteris flourished well during the middle Triassic and continued at least upto the Rhaetic, in association with Dicroidium. The Glossopteris-Dicroidium assemblage thus is not a time-restricted transitional zone. Dicroidium with associated forms characterises a flora which is distinct from the older Glossopteris flora and the younger Ptillophylum flora. A three-fold biostratigraphic subdivision of the Indian Gondwana thus has been advocated.     

Plant–arthropod interactions in gymnosperm leaves from the Early Permian of Patagonia,Argentina

Evidence of plant–arthropod interactions in three orders of gymnosperms is documented in at least five localities from Lower Permian strata of the Río Genoa Formation (Patagonia, Argentina). Arthropod damages were identified in Glossopteris, Gangamopteris, Cordaites and Gingkoites leaves, corresponding to four interactive categories: margin feeding, hole feeding, surface feeding, and oviposition. In addition, a Permian insect trace not previously recorded is described on Glossopteris wilsonii leaves. The diversity of arthropod damage is consistent with the diverse flora of the Río Genoa Formation. In turn, the patterns of arthropod and plant–arthropod interaction provide constraints on the ecology and paleoclimate of Western Gondwana during the Early Permian.     

Sur une flore a Glossopteropsida et Lycopsida de Namibie (Sud-Ouest Africain)

The study of imprints of fossil plants collected in the Permian from the country of Hammanskraal (Namibia) leads to the following identifications: Glossopteris sp., Gangamopteris sp., Noegerrathiopsis sp., Gondwanidium sp., Asterotheca sp. and Lycopodiopsis derbyiB. Renault, Lycopodiopsis costilatus n. sp., Brasilodendron pedroanum(W. Carruthers) W.G. Chaloner & alii, Brasilodendron africanum n. sp. This flora has affinities with some fossil floras from South Africa and from Brazil, and is, probably, of upper Permian age.     

Record of Lower Gondwana megafloral assemblage from Lower Kamthi Formation of Ib River Coalfield, Orissa, India

Recent investigations carried out in the Ib River Coalfield, Mahanadi Master Basin, Orissa, identified some fossiliferous beds in the Lower Gondwana deposits. Two exposures of the Lower Kamthi Formation yielded diverse and abundant plant remains, which includeNeomariopteris, Vertebraria, and a scale leaf along with 14Glossopteris species otherwise mapped as Barren Measures and Upper Kamthi formations.Glossopteris indica dominates the flora (22.78%) followed byG. communis (17.72%) andG. browniana (13.92%). Based on megafloral assemblages, different beds exposed at Gopalpur and Laxamanpur Pahar are assigned here to the Lower Kamthi Formation (Late Permian). The floristic composition suggests that a warm and humid climate prevailed during the Late Permian. The status of the Kamthi Formation in the Ib River Coalfield has been redefined in the present study.     

Evolution of the glossopterid gymnosperms from Permian Gondwana

Our understanding of the glossopterid gymnosperms from the Permian of Gondwana has recently been greatly enhanced through the study of anatomically preserved plant remains in cherts from several localities in Australia and Antarctica. Studies ofGlossopteris leaves, leaf-stem attachment, stem structure and wood anatomy,Vertebraria roots, ovule- and pollen-bearing reproductive structures and putative glossopterid pollen and ovules demonstrate that the glossopterids were a diverse group of sophisticated gymnosperms. Comparative studies of different Permian chert floras show that while some glossopterid elements are widespread, other taxa appear to be more localized in their distribution. As information from petrified plant-bearing cherts becomes available, it can be used to reconstruct whole glossopterid plants and establish their paleogeographic distribution.     

An efficient method for estimating vein density of Glossopteris and its application

Glossopteris-type leaves are the most abundant floristic element from the Gondwanan continent and are recorded throughout the Permian, which was a period of extreme icehouse-to-hothouse climatic global change. Fossil leaf traits can be useful for the reconstruction of palaeoenvironments and identification of climatic changes throughout geological time, but the conservative morphology of Glossopteris leaves has thus far made them difficult to use for this purpose. If the characters of Glossopteris can be better quantified then it should make them useful for tracking environmental changes over a wide geographical area and over a long time interval. Venation density is a highly variable leaf trait that might be useful for this purpose. This trait can be calculated, usually as vein length per centimetre squared, but this can be a time-consuming procedure. In this paper we propose a new rapid method to estimate venation density in a conical sector of Glossopteris leaf lamina using an accurate linear model whose predictors are three linear venation densities, measured as veins per centimetre. In addition to substantially reducing the data collection time, it is less biased and more reproducible than methods applied previously with this leaf type. Using this more robust method, preliminary results significantly distinguish the venation densities of leaves produced in wet and drier ecosystems, matching a pattern similar to modern plants. This is the first survey using a large sample size to reveal that environmental stress controlled the vein architecture of Palaeozoic plants, in a manner similar to plants in modern ecosystems.     

A Suite of Dermestid Beetle Traces on Dinosaur Bone from the Upper Jurassic Morrison Formation,Wyoming, USA

Most studies of insect traces on fossil bone deal with one or two trace morphs found on isolated bone fragments, making it difficult to identify the trace-maker and its behavior. We report the discovery of a suite of insect traces on an articulated Camptosaurus dinosaur skeleton that permits the identification of the trace-maker and interpretations of its behavior. The traces include mandible marks, pits, and shallow bores on cortical bone, and deep, meandering furrows and tunnels (borings) on articular surfaces. The interiors of bones are intensely mined, and the cavities and borings are filled with fine bone fragments (insect frass). The distinctive mandible marks consist of opposing sets of parallel grooves, indicating the maker had two apical teeth set on symmetrical mandibles and that all of the traces were made by a single taxon. Comparison of the fossils with the mandible morphology and bone traces of extant insects indicates dermestid beetles made the traces. Based on extant dermestid behavior, soft tissues were likely absent and the bones were lipid-laden when the traces were made. Examination of more than 5,000 bones from the Morrison and Cedar Mountain formations shows insect traces on bone are common but overlooked and that many bones are substantially damaged by insect mining. The key to the recognition of these important yet subtle traces is a search model and an intense, oblique light source.     

Leaf beds in the Early Miocene lacustrine deposits of the Geumgwangdong Formation,Korea: Occurrence,plant–insect interaction records,taphonomy and palaeoenvironmental implications

Occurrence, preservation and evidence of plant–insect interactions in the leaf deposits of the early Miocene Geumgwangdong Formation are described, and the taphonomy and palaeoenvironmental implications are interpreted. The Geumgwangdong leaf beds are tuffaceous lacustrine deposits consisting mainly of thin-bedded sediments, including shale. Deposition was dominated through the vertical aggradation of fine-grained sediments by suspension sedimentation, rather than by the fluvial deposition of coarse-grained sediments. The majority of the fossil leaves were preserved by compression rather than merely preserved as impressions. The Geumgwangdong leaf deposits can be characterised as a wind-transported, dysaerobic, deep-water, lake taphofacies with some influence of water-transport. The fossil flora of the Geumgwandong Formation consists of 64 taxa belonging to 27 families and 43 genera. The dominant taxa were Metasequoia, Fagus, Betula, Quercus, Acer, Zelkova, and Leguminosae, which is comparable to the Early Miocene cool–temperate Aniai-type Flora of north-east Japan. The similarity between the lake settings of the Geumgwangdong Formation and the Aniai Coal-bearing Formation might have been a factor in the development of similar plant–fossil assemblages. Although traces of insect damage in the fossil leaves of the Geumgwangdong Formation were commonly observed, more than 90% of the damaged leaves showed a low level of diversity and degree of insect damage (< 10%), which is indicative of a cool–temperate palaeoclimatic condition. Despite latitudinal differences and geographic separation, the development of similar floras in the Geumgwangdong Formation of south-east Korea and the Aniai Coal-bearing Formation of north-east Japan during the early Miocene could have been influenced by the incipient NW–SE sea-floor spreading that resulted in the opening of the East Sea (Sea of Japan), which might have enabled floral migration between the two regions. This study provides useful data for understanding not only the taphonomy and palaeoenviroments of the leaf deposits, but also the spatial development of the flora resulting from palaeogeographic changes driven by tectonic movement during the early Miocene in Far East Asia.     

In situ occurrence of a gall midge (Insecta,Diptera, Cecidomyiidae) on fossilized angiosperm leaf cuticle fragments from the Pliocene sediments of eastern India

In situ preservation of fossil insect damage in plant fossils is an excellent tool to study the coevolution of flora and fauna through geological time, but finding both damage and the insect causing that damage in the same specimen is a very rare phenomenon. Galling is a common form of angiosperm leaf damage, which can be regarded as a kind of extended phenotype of the causal insects, essentially the gall midges, but galls usually lack remains of the insects themselves. Here we report the in situ occurrence of a gall midge (Insecta, Diptera, Cecidomyiidae) as well as its pupal exuviae on the abaxial cuticular surface of fossilized leaf cuticle fragments of Fabaceae leaves (cf. Albizia) that also bear galls, recovered from the latest Neogene (Rajdanda Formation, Pliocene) sediments of the Chotonagpur Plateau, Jharkhand, northeastern India. This Pliocene gall midge features well-preserved legs, segmented antenna with distinct and enlarged scape, elongate curved setae, and longer than broad terminal plate of the ovipositor lamellae. The in situ presence of a gall midge on a host fabaceous leaf cuticle indicates the existence of a host-ectoparasite relationship in the ancient warm and humid tropical monsoon-influenced forests of eastern India during the Pliocene. This is the first authentic fossil record of an in situ phytophagous insect of Cecidomyiidae from India, as well as southeast Asia. Although the identification of the recovered phytophagous insect associated with the fossil leaf cuticle is only possible to family level, this find reveals that such plant-insect relationships existed in the Pliocene of eastern India.     

Mine and gall predation as top down regulation in the plant–insect systems from the Cretaceous of Negev, Israel

Fossil evidence of predation on leaf mines and galls opens the way to analyzing regulatory circuits in plant–insect interaction systems and assessing their evolutionary advancement. In the Cretaceous (mid-Turonian) flora of Negev, Israel, predation traces vary from the entire gall or mine excisions to minute punctures and slits over the mine tracks. Bite marks on the borders of predation holes representing different mouthpart morphologies may show how diverse the predators were. The efficiency of predation as a top down regulation force is attested on the basis of the gall and mine abundance, gall morphologies, mine configurations, co-occurrence of different mine types on leaves, and temporary mining. In turn, the regulation efficiency is considered as a criterion of evolutionary advancement of the plant–insect community as a whole. It is suggested that the coeval Cretaceous coastal and inland communities differed in the relative significance of top-down regulation.     

Trace fossil evidence of predation upon bone‐eating worms on a baleen whale skeleton from the Oligocene of New Zealand

The osteophagous worm Osedax (Annelida: Siboglinidae) colonizes vertebrate bones in deep‐sea environments globally. Osedax bioerosion of modern bones suggests a potentially destructive agent in the marine vertebrate fossil record, but the dearth of published reports of abundant Osedax traces suggests an uncertain taphonomic influence of this organism. This study reports Osedax traces (Osspecus boreholes, pockmarks and collapsed galleries) in an Oligocene baleen whale (Cetacea: Eomysticetidae) from New Zealand, which constitute the first record of fossil Osedax traces from the southern hemisphere. Some Osedax traces are cross‐cut by linear biogenic scrape marks, implying that sharks or bony fish fed upon Osedax worms, a process which compounds or potentially accelerates worm‐inflicted damage to vertebrate bones in marine environments.     

Zooidogamy in the Late Permian genus<Emphasis Type="Italic"> Glossopteris</Emphasis>

We describe details of anatomically preserved fossil glossopterid ovules from the Late Permian of Queensland, Australia, that contain several pollen tubes at various stages of releasing flagellated sperm. Each sperm is approximately 12.7 m long and 13.9 m wide, with a conspicuous spiral structure comprised of a series of dots that resemble the position of basal bodies of flagella aligned along the multilayered structure (MLS). This configuration is similar to the helically arranged flagella in the sperm of cycads, Ginkgo, and many pteridophytes. However, the motile gametes of Glossopteris are considerably smaller than those of Ginkgo and cycads, and more similar in size, number of basal bodies, and number of gyres in their helix to pteridophyte forms. Glossopteris thus shares the intermediate stage of motile male gamete formation and apparently that of haustorial pollen tubes with cycads and Ginkgo.An erratum to this article can be found at     

The diversity and paleoenvironmental significance of Calophyllum (Clusiaceae) from the Miocene of southeastern China

Abstract

Three species within the genus Calophyllum collected from middle Miocene Fotan Group sediments in Zhangpu County, Fujian, southeastern China are described in this paper. These fossils include Calophyllum zhangpuensis sp. nov., Calophyllum striatum, and Calophyllum suraikholaensis. The new fossil species C. zhangpuensis sp. nov. is oval, possesses entire leaves with closely spaced parallel secondary veins and has a round, or slightly retuse, apex. These specimens represent the first known fossil records of this relative wide leaf-type form of Calophyllum from China and have a length:width (L:W) ratio less than 3:1. In combination with the known modern geographic distribution and habitats of this wide leaf-type Calophyllum and other plants, data suggest that the middle Miocene Fotan flora is indicative of a warm climate. Thus, based on available fossil data, we speculate that this genus probably originated in India during the Paleocene before spreading from India to Bangladesh and into China, Sumatra, Malaysia, Indonesia, and Java during the Neogene, leading to its modern distribution. At least, the 3 fossil species in this region can explain floristic exchange between India, Fujian, and South China, which is consistent with previous studies; the occurrence of these 3 species indicates that Calophyllum began to diversity in China no later than the Miocene.     

New evidence of the reproductive organs of Glossopteris based on permineralized fossils from Queensland,Australia. II: pollen-bearing organ Ediea gen. nov

Ediea homevalensis H. Nishida, Kudo, Pigg & Rigby gen. et sp. nov. is proposed for permineralized pollen-bearing structures from the Late Permian Homevale Station locality of the Bowen Basin, Queensland, Australia. The taxon represents unisexual fertile shoots bearing helically arranged leaves on a central axis. The more apical leaves are fertile microsporophylls bearing a pair of multi-branched stalks on their adaxial surfaces that each supports a cluster of terminally borne pollen sacs. Proximal to the fertile leaves there are several rows of sterile scale-like leaves. The pollen sacs (microsporangia) have thickened and dark, striate walls that are typical of the Arberiella type found in most pollen organs presumed to be of glossopterid affinity. An examination of pollen organs at several developmental stages, including those containing in situ pollen of the Protohaploxypinus type, provides the basis for a detailed analysis of these types of structures, which bear similarities to both compression/impression Eretmonia-type glossopterid microsporangiate organs and permineralized Eretmonia macloughlinii from Antarctica. These fossils demonstrate that at least some Late Permian pollen organs were simple microsporophyll-bearing shoot systems and not borne directly on Glossopteris leaves.     

Biodamage on Phylladoderma leaves from the Upper Permian of the Pechora Basin

A new insect damage type on leaves Phylladoderma arberi Zalessky, 1913 from the Upper Permian of the Pechora Basin (Adz’va River, Russia) is described. These are punctures about 120 μm in diameter surrounded by circular spots with a dark rim. We suppose that these feeding traces were made by palaeodictyopteroid nymphs.     

CIBOTIUM OREGONENSE: AN EOCENE TREE-FERN STEM AND PETIOLES WITH INTERNAL STRUCTURE

Cibotium oregonense sp. nov. is described from the Upper Eocene of Medford, Oregon. The fossil comprises petiole bases and stem periphery of a large fern preserved via permineralization. A stele devoid of sclerenchymatous sheathing and a petiole vascularized with a large number of leaf traces in a cyatheacean pattern characterize the fossil. A distinctive U-shaped interior series of leaf traces allows assignment to the genus Cibotium. This fossil provides evidence that the genus Cibotium was represented by an arborescent species with large leaves in the Early Tertiary of western North America.     

ANATOMICALLY PRESERVED GLOSSOPTERIS STEMS WITH ATTACHED LEAVES FROM THE CENTRAL TRANSANTARCTIC MOUNTAINS,ANTARCTICA

Stems and buds of Glossopteris skaarensis Pigg and buds of G. schopfii Pigg from the Permian Skaar Ridge locality in the central Transantarctic Mountains, Antarctica demonstrate the first anatomically preserved glossopterids known with stem/leaf attachment. Stems of G. skaarensis are 1–12 mm in diameter ( = 3.1 mm) with a broad pith, poorly defined primary xylem, and a zone of secondary xylem up to 6 mm thick. Pycnoxylic wood conforming to Araucarioxylon Kraus is composed of tracheids with uni- to biseriate oval to hexagonal bordered pits on radial walls, uniseriate rays one to a few cells high, and cupressoid to taxodioid cross-field pitting. Stems have a narrow zone of secondary phloem, aerenchymatous cortex with scattered sclereids, and sometimes a narrow periderm. Two wedge-shaped leaf traces each bifurcate to form four strands in the base of each petiole. Small axillary branches are vascularized by double branch traces that fuse at the margin of the main axis. Buds of G. skaarensis have leaves with narrow lateral laminae and a thickened midrib containing a wide lacuna, delicate vascular strands, and a prominent hypodermis. In contrast, buds of G. schopfii have uniformly thick leaves with prominent, circular vascular bundle sheaths. These anatomical details are used to reconstruct individual types of glossopterid plants, providing new information toward understanding the ecology and evolution of this important group of Permian seed plants.     

Scorpionid Resting Trace from The Lower Permian of Southern New Mexico,USA

We describe an arthropod body impression associated with arthropod trackways of the ichnogenus Stiaria from the Lower Permian (upper Wolfcampian) Robledo Mountains Formation (Hueco Group) in the Prehistoric Trackways National Monument of southern New Mexico. The probable producer of these traces was a scorpion, and we name the likely scorpionid resting trace Alacranichnus braddyi, new ichnogenus and ichnospecies. There are no prior reports of scorpionid body impressions from terrestrial settings in the fossil record.