The palaeoxylological record of Metapodocarpoxylon libanoticum (Edwards) Dupéron-Laudoueneix et Pons and the Gondwana Late Jurassic–Early Cretaceous continental biogeography

Aim Vertebrates, palynomorphs and leaf floras each give a different picture of continental biogeography of Northern Gondwana during the Middle Jurassic–Early Cretaceous interval. A new biogeographical marker is required to get a clearer picture. Location Northern part of the Gondwana during the Middle Jurassic–Early Cretaceous interval. Methods Comparisons and correlations of wood data from the literature and new material. Results We have selected Metapodocarpoxylon Dupéron‐Laudoueneix et Pons because it has a restricted distribution, temporally and geographically; it is a well‐defined Mesozoic fossil wood monospecific genus, and there are wide‐ranging data on its distribution. Conclusions Metapodocarpoxylon distribution draws a clear latitudinal belt extending from Lebanon westward to Peru. Climate being the main factor of plant distribution at a global scale, the Metapodocarpoxylon area probably underlines a climatic belt. This has several implications, for example, choosing among different Global Circulation Models or discussing dinosaur distribution.     

A revision of the sauropod dinosaur genus ‘Bothriospondylus’ with a redescription of the type material of the Middle Jurassic form ‘B. madagascariensis’

Abstract: The sauropod dinosaur ‘Bothriospondylus’, originally named on the basis of Late Jurassic remains from England, is demonstrated to be invalid, and the characters used to diagnose it are shown to be obsolescent features which are widespread throughout Sauropoda. Material referred to this genus spans a temporal range from the Middle Jurassic until the early Late Cretaceous and has been described from five different countries, across three continents. These remains represent a wide array of sauropod groups, comprising non‐neosauropod eusauropods, a macronarian, titanosauriforms (including at least one definite brachiosaurid) and a rebbachisaurid. The type material of the Middle Jurassic ‘B. madagascariensis’ represents a derived non‐neosauropod eusauropod and possesses two potential autapomorphies. However, as a result of the fragmentary nature of the material and the uncertainty surrounding its association, a new taxon is not erected. Of the numerous specimens referred to ‘Bothriospondylus’, however, several remains are considered diagnostic: Ornithopsis hulkei (Early Cretaceous, UK), Lapparentosaurus madagascariensis (Middle Jurassic, Madagascar) and Nopcsaspondylus alarconensis (early Late Cretaceous, Argentina). At least three types of sauropod were present in the Bathonian (Middle Jurassic) of north‐west Madagascar, with a basal eusauropod (Archaeodontosaurus), a more derived eusauropod (‘B. madagascariensis’) and a titanosauriform (Lapparentosaurus) all approximately contemporaneous. Palaeocontinental reconstructions suggest that Middle Jurassic Madagascan sauropods would still have been capable of global biotic interchange, and this is perhaps reflected in their diverse assemblage. Re‐evaluation of these Malagasy forms has shed new light on this important time period in sauropod evolution.     

Changes in lifestyle and habitat of Zoophycos‐producing animals related to evolution of phytoplankton during the Late Mesozoic: geological evidence for the ‘benthic‐pelagic coupling model’

The trace fossil Zoophycos characterized by complex, three‐dimensional morphology with systematic internal structures occurs throughout the Phanerozoic marine sediments. The specimens of Zoophycos examined herein consist of a downward and helical spreite and are a product of the excretory behaviour of endobenthic detritus feeders. They are divided into two basic types: pre‐Jurassic and post‐Cretaceous types on the basis of whorls of spreiten in a single specimen. The pre‐Jurassic type has fewer than four whorls. In contrast, most of the post‐Cretaceous specimens exhibit spreite with multiple coils more than ten whorls. The abrupt increase in whorl number during the Cretaceous suggests that the sedentary lifestyle of the producer should change from a short‐term stay to long‐term or permanent occupation of the same burrow. Timing of the lifestyle change the Zoophycos producers seems to be closely related to the deep‐seaward migration of their habitats. The change in lifestyle and migration of Zoophycos‐producing animals during the Cretaceous might be attributable to the establishment of eutrophic bottom conditions in the deep sea. These changes seem to be associated with the flux of large amounts of phytodetrital food produced by phytoplankton, which experienced an explosive increase in species diversity during the Late Jurassic to the Late Cretaceous. The series of changes in lifestyle and habitat of the Zoophycos animals during the Late Mesozoic can serve as one piece of geological evidence for the ‘benthic‐pelagic coupling model’.     

Highly Similar Prokaryotic Communities of Sunken Wood at Shallow and Deep-Sea Sites Across the Oceans

With an increased appreciation of the frequency of their occurrence, large organic falls such as sunken wood and whale carcasses have become important to consider in the ecology of the oceans. Organic-rich deep-sea falls may play a major role in the dispersal and evolution of chemoautotrophic communities at the ocean floor, and chemosynthetic symbiotic, free-living, and attached microorganisms may drive the primary production at these communities. However, little is known about the microbiota thriving in and around organic falls. Our aim was to investigate and compare free-living and attached communities of bacteria and archaea from artificially immersed and naturally sunken wood logs with varying characteristics at several sites in the deep sea and in shallow water to address basic questions on the microbial ecology of sunken wood. Multivariate indirect ordination analyses of capillary electrophoresis single-stranded conformation polymorphisms (CE-SSCP) fingerprinting profiles demonstrated high similarity of bacterial and archaeal assemblages present in timbers and logs situated at geographically distant sites and at different depths of immersion. This similarity implies that wood falls harbor a specialized microbiota as observed in other ecosystems when the same environmental conditions reoccur. Scanning and transmission electron microscopy observations combined with multivariate direct gradient analysis of Bacteria CE-SSCP profiles demonstrate that type of wood (hard vs. softwood), and time of immersion are important in structuring sunken wood bacterial communities. Archaeal populations were present only in samples with substantial signs of decay, which were also more similar in their bacterial assemblages, providing indirect evidence of temporal succession in the microbial communities that develop in and around wood falls.     

DUROPHAGOUS PREDATION ON MIDDLE JURASSIC MOLLUSCS, AS EVIDENCED FROM SHELL FRAGMENTATION

Abstract:  Durophagous (shell-crushing) predation is known from the beginning of the Phanerozoic, but it has been suggested that modern intensity was not reached until the Late Cretaceous and Early Cenozoic, when specialized marine durophagous taxa increased in diversity. In this paper, evidence of durophagous predation on Middle Jurassic communities of molluscan prey is presented on the basis of distinct accumulations of fossil remains in the Polish Jura (south-central Poland) that contain characteristic, angular shell fragments with sharp, non-abraded margins. The diverse fossil content of the accumulations studied, consisting of either benthic or nektic/nekto-benthic taxa, indicates that the potential predatory taxon was an opportunistic generalist, most probably fish. On the basis of taphonomic observations, the faunal accumulations are interpreted to represent regurgitated remains (pellets). The common occurrence of such accumulations in the Middle Jurassic clays of the Polish Jura indicates that durophagous predation has been intense since the mid-Mesozoic, at least locally.     

A new decapod crustacean faunule from the Middle Jurassic of north‐west France

Abstract: Decapod crustacean material collected recently from the lower Callovian (Middle Jurassic) in Maine‐et‐Loire (north‐west France) comprises two new species of prosopid and one new species of tanidromitid crabs, of the genera Nodoprosopon and Tanidromites, respectively. Also represented in this faunule is a probable paguroid anomuran, in the form of isolated chelae here assigned to the genus Orhomalus, as well as appendicular remains of unknown affinity; some of the latter might belong to prosopid crabs. These anomurans and brachyurans co‐occur with a diverse benthic fauna in limestones with abundant iron ooids; their main interest lies in the fact that they add valuable data to the rather poor record of Middle Jurassic decapod crustaceans.     

Spatial pattern of downed logs and wood‐decaying fungi in an old‐growth Picea abies forest

Abstract. Since many wood‐living forest species are influenced by the dynamics of coarse woody debris (CWD), information about the spatial pattern of CWD under natural conditions is essential to understand species distributions. In this study we examined the spatial pattern of downed logs and wood‐decaying fungi in an old‐growth boreal Picea abies forest in northwestern Sweden that is governed by gap‐phase dynamics. The spatial pattern of wood‐decaying fungi was studied to draw conclusions about species dispersal abilities. A total of 684 logs with a diameter > 10 cm were mapped and analysed with Ripley's K‐function. The distribution of all logs taken together displayed a significant aggregated pattern up to 45 m. The different decay stages also deviated from random expectations. Fairly fresh logs and logs in the middle decay stage were clumped up to about 25 and 35 m respectively, and late decayed logs aggregated up to 95 m. Logs with diameters from 10–29 cm were aggregated up to 25 m, whereas logs ≥30 cm diameter were randomly distributed. The result suggests that gap‐dynamics do have an impact on the spatial pattern of the CWD, creating fine‐scale clumping. The random distribution of large logs may result from the slightly regular spacing of large living trees. The spatial patterns of 16 species (n > 20) of wood‐decaying fungi were analysed with Ripley's K‐function. Three patterns were aggregated, for Gloeophyllum sepiarium, Coniophora olivacea and Vesiculomyces citrinus. These results indicate that the distribution of most species at the stand level is generally not influenced by dispersal limitations.     

Phase contrast X‐ray synchrotron microtomography and the oldest damselflies in amber (Odonata: Zygoptera: Hemiphlebiidae)

Electrohemiphlebia barucheli gen. et sp. nov. and Jordanhemiphlebia electronica gen. et sp. nov. , two new genera and species are described, based on exceptional inclusions of hemiphlebiid damselflies in Cretaceous amber from France and Jordan. The type specimen of E. barucheli was studied using phase contrast X‐ray synchrotron microtomography, giving exceptional images and detailed information. Its comparison with the recent Hemiphlebia mirabilis confirms the attribution of several Cretaceous damselflies to the Hemiphlebiidae, showing that this particular group was widespread in the Early Cretaceous and probably originated in the Late Jurassic or earlier. The ecological niches today occupied by the small coenagrionoid damselflies were occupied during the Triassic and Jurassic by Protozygoptera, hemiphlebiids during the Early Cretaceous, and modern taxa in the Cenozoic.     

Fossil wood of <Emphasis Type="Italic">Sequoioxylon burejense</Emphasis> sp. nov. (Taxodiaceae) from the Upper Cretaceous of the Zeya-Bureya Basin (Russian Far East)

A new species Sequoioxylon burejense Blokhina et M. Afonin (Taxodiaceae), identified on the basis of anatomical features of fossil wood from the Middle Maastrichtian (Upper Cretaceous) of the Zeya-Bureya Basin, Amur Region, Russian Far East, is described. The new species is characterized by mixed anatomical features of the modern representatives of the tribe Sequoieae. Cretaceous wood of Taxodiaceae was found in the Amur Region for the first time.     

Pycnogonid‐cnidarian trophic interactions in the deep Monterey Submarine Canyon

Abstract. Whale carcasses, sunken wood, and cold seeps provide organically enriched oases in the food‐limited deep‐sea benthos. At three such enriched habitats in Monterey Bay, CA, at a depth of nearly 3000 m, we observed pycnogonids (sea spiders) of at least two species, Colossendeis gigas and C. japonica, feeding on sea anemones that were commonly found there. Submersible remotely operated vehicles provided direct observations of feeding, as well as high definition video and photographic images. We recorded the co‐occurrence of both pycnogonids and prey anemones during ten of 12 visits during 2002–2006. Anemones and pycnogonids were conspicuously more abundant at these oases than in the surrounding benthos. The sedentary anemone Anthosactis pearseae was attached directly to whalebones while the pom‐pom anemone, Liponema brevicornis, was found resting on soft sediment, rolling in benthic currents, or accumulating where these currents were disrupted by topography, as at whale falls, wood falls, and clam fields. Both pycnogonid species were observed feeding on these anemones, either as predators or as micropredators.     

Higher‐level phylogeny and evolutionary history of Pentatomomorpha (Hemiptera: Heteroptera) inferred from mitochondrial genome sequences

The higher‐level phylogeny of Pentatomomorpha, the second largest infraorder of true bugs (Hemiptera: Heteroptera), which includes many important agriculture and forestry pests, has been debated for decades. To investigate the phylogeny and evolutionary history of Pentatomomorpha, we assembled new mitochondrial genomes for 46 species through next‐generation sequencing of pooled genomic DNA. Based on a much broader taxon sampling than available previously, Bayesian analyses using a site‐heterogeneous mixture model (CAT+GTR) resolved the higher‐level phylogeny of Pentatomomorpha as (Aradoidea + (Pentatomoidea + (Coreoidea + (Lygaeoidea + Pyrrhocoroidea)))). There was a transition from trnT/trnP to trnP/trnT in the common ancestor of Pyrrhocoroidea, which indicates that this gene rearrangement could be an autapomorphy for Pyrrhocoroidea. Divergence time analyses estimated that Pentatomomorpha originated c. 242 Ma in the Middle Triassic, and most of the recognized superfamilies originated during the Middle Jurassic to Early Cretaceous. The diversification of families within Pentatomomorpha largely coincided with the radiation of angiosperms during the Early Cretaceous.     

Foraminiferan tests and dasycladalean thalli as cryptic microhabitats for thaumatoporellacean algae from Mesozoic (Late Triassic–Late Cretaceous) platform carbonates

Thaumatoporellacean algae are widespread constituents in Middle Triassic–Cretaceous shallow-marine carbonates of the Tethyan realm. Based on various examples from Mesozoic limestones of Mediterranean platforms (e.g., Dinaric, Apenninic, Apulia) and rare records of Iberia (Pyrenees), Saudi Arabia and Mexico, it is shown that thaumatoporellaceans commonly dwelt as cryptoendoliths in the tests of larger benthic foraminifera and the thalli of dasycladalean algae. Their high morphological plasticity allowed the test invasion and the adaptation to the available interior spaces (chambers, apertures). The temporal distribution of cryptoendolithic thaumatoporellaceans with first records in the Late Triassic, shows acme intervals in Early–Middle Jurassic and Early–Late Cretaceous times. Within the foraminiferans, the thaumatoporellaceans were erroneously considered as an integral part of the test, respectively, phrenoteca-like structures (species Biokovina gradacensis) in the Lower Jurassic and trematophore (species Scandonea? mediterranea) in the Upper Cretaceous. Therefore, the presence of phrenoteca-like structures in the Biokovinidae, being part of the family diagnosis, is challenged. The comparably thin walls of the cryptoendolithic thaumatoporellacean algae are interpreted as an adaptation to the poorly illuminated microhabitats (photoadaptation) in order to maximize light capture for photosynthesis.     

Pseudoplanktonic lifestyle of the Triassic crinoid Traumatocrinus from Southwest China

Colonies of Traumatocrinus (Echinodermata, Crinoidea) attached to driftwood from the lower Upper Triassic (Carnian) Xiaowa Formation of the Guanling area (Guizhou, Southwest China) document a pseudoplanktonic lifestyle for this specialized offshoot of the otherwise benthic Middle Triassic Encrinidae. After the end-Carnian decline of Traumatocrinus, its ecological niche was subsumed in Norian by genera derived from another benthic family (Holocrinidae) with convergent morphological modifications. After the Toarcian (Lower Jurassic), this niche disappeared, possibly due to the emergence of wood-boring bivalves.     

When does dead wood turn into a substrate for spruce replacement?

Question: How many years must elapse for freshly fallen Picea abies stems to be transformed into a substrate for P. abies recruitment? Location: Natural sub‐alpine spruce forest, 1200–1300 m a.s.l., western Carpathians, Poland. Methods: Coarse woody debris (CWD) was measured on nine plots with a total area of 4.3 ha. All individuals of P. abies regeneration growing on dead wood were counted and their age was estimated. Decay rate of logs was determined using dendrochronological cross‐dating of samples from logs in different decay stages. Results: Although CWD covered only 4% of the forest floor, 43% of the saplings were growing on decaying logs and stumps. The highest abundance of P. abies recruitment occurs on logs 30–60 years after tree death, when wood is in decay stages no. 4–7 (on an 8 degree decay scale). However, much earlier colonization is possible. The first seedlings may germinate on a log during the second decade after tree death and survive for decades. Their slow growth is possibly due to the gradual progressive decomposition of wood. Conclusions: This study confirms the importance of decaying wood for P. abies recruitment. The decaying logs exhibit continuous and favourable conditions for the germination of P. abies seeds throughout their decay process. Logs, irrespective of their decay stage and age, are colonized by young seedlings. This recruitment bank is constantly renewed.     

Review of Japanese Dinosaur Track Localities: Implications for Ichnotaxonomy,Paleogeography and Stratigraphic Correlation

Nine dinosaur ichnospecies from the Lower Jurassic to Upper Cretaceous of Japan, including two that are new, are described herein. The new ichnotaxa are Asianopodus pulvinicalx ichnogen. et ichnosp. nov. and Schizograllator otariensis ichnosp. nov. The Japanese ichnotaxa are allied to Lower Jurassic ichnospecies in South China, North America, Western Europe and South Africa, and Upper Jurassic to Lower Cretaceous ichnospecies from Southeast and East Asia. This suggests they were part of a global ichnofauna before continental drift began in the Middle Jurassic, leading to the development of a more endemic dinosaur fauna in the Cretaceous. At least two assemblages, an ornithopod-gracile-toed theropod-dominated community, in northeastern Asia, and a robust theropod- and sauropod-dominated community in the southern part of the continent, existed in the Cretaceous. This parallels North American dinosaur distribution patterns in the Cretaceous and seems to be a reflection of paleolatitudinal controls.     

Remarkably preserved benthic organisms and their traces from a Middle Triassic (Muschelkalk) mud flat

Knaust, D. 2010: Remarkably preserved benthic organisms and their traces from a Middle Triassic (Muschelkalk) mud flat. Lethaia, Vol. 43, pp. 344–356. A new Fossil‐Lagerstätte is reported from the Middle Triassic of Germany, preserving Foraminifera, Nematoda, Platyhelminthes, Nemertea, Annelida and a range of Arthropoda together with their traces. This is the oldest fossil record of free‐living nematodes and turbellarians, and the first occurrence of nemerteans in the Mesozoic. The rare preservation of the benthic associations together with their traces is unique; especially the abundant occurrence of different phyla as meiofauna (organisms with shortest dimension between 0.06 and 1 mm) provides an insight into the palaeoecological conditions of a 240‐Ma‐old muddy tidal flat. The preservation of benthic animals at the termination of their traces offers the exclusive opportunity to assign producers to the trace fossils. The results show that the discussed phyla were already established in the early Mesozoic in a similar diversity and composition as in modern analogues. The new Fossil‐Lagerstätte has the potential to prove a number of soft‐bodied taxa immediately after the end‐Permian mass extinction, which has wide‐ranging implications for phylogenetic interpretations. □Benthos, soft‐bodied organisms, Fossil‐Lagerstätte, Muschelkalk, trace fossils, Triassic.     

The importance of forest type,tree species and wood posture to saproxylic wasp (Hymenoptera) communities in the southeastern United States

Although the forests of the southeastern United States are among the most productive and diverse in North America, information needed to develop conservation guidelines for the saproxylic (i.e., dependent on dead wood) fauna endemic to the region is lacking. Particularly little is known about the habitat associations and requirements of saproxylic parasitoids even though these organisms may be even more vulnerable than their hosts. We sampled parasitoids emerging from dead wood taken from two forest types (an upland pine-dominated forest and a lowland hardwood-dominated forest), three tree species (Liquidambar styraciflua L., Pinus taeda L., and Quercus nigra L.) and two wood postures (standing dead trees (i.e., snags) and fallen logs) in South Carolina. Parasitoid abundance did not differ between forest types or among tree species, but did differ between wood postures, being higher in snags than logs. This difference may have been due to the logs being in contact with the ground or surrounding vegetation and therefore less accessible to parasitoids. Parasitoid abundance and density decreased with height on both snags and logs. Species richness did not differ between forest types, among tree species or between wood postures. According to analysis of similarities, parasitoid communities did not differ between forest types, but did differ among tree species. The wasp communities associated with the different tree species and posture combinations were distinct. In addition, communities associated with the upper boles and crowns of snags were distinct from those occurring lower on snags. These results emphasize the importance of maintaining tree diversity in managed forests as well as retaining or creating entire snags at the time of harvest.     

PARAPHYLLANTHOXYLON ALABAMENSE—A NEW SPECIES OF FOSSIL DICOTYLEDONOUS WOOD

A new species of fossil wood, Paraphyllanthoxylon alabamense, is described from silicified logs collected in Macon and Elmore counties from the Tuscaloosa Group, Cretaceous, Cenomanian-Turonian Stage. All of the logs examined from this area have the same general characteristics and are placed in the new species. Paraphyllanthoxylon alabamense shows many characteristics intermediate between the two previously described species but it is not identical with either of them. This wood is probably not identical with any living type but it resembles certain members of the Anacardiaceae, Buseraceae, Euphorbiaceae, and Sapindaceae. The large size and abundance of logs of Paraphyllanthoxylon alabamense suggest that it was a dominant Cretaceous forest tree.     

Wood Decomposition of Cyrilla racemiflora (Cyrillaceae) in Puerto Rican Dry and Wet Forests: A 13‐year Case Study1

We studied the decomposition of Cyrilla racemiflora logs over a 13‐yr period in tropical dry and wet forests in Puerto Rico. The mean mass loss, ratio of soft to hard wood, nutrient concentrations, and the diversity of wood‐inhabiting organisms were greater in logs decomposing in the dry forest than in the wet forest. Termites were also more abundant in the logs collected from the tropical dry forest than the tropical wet forest. High moisture content and a low animal diversity on the logs in the wet forest seem to retard wood decay in this habitat. Wood decay rates in the tropical dry forest can be related to the high diversity of species and functional groups of wood‐inhabiting organisms.     

A well‐preserved isopod from the Middle Jurassic of southern Germany and implications for the isopod fossil record

A new isopod species, Eonatatolana geisingensis gen. et sp. nov., is described from Middle Jurassic shallow‐water sediments of southern Germany. It shows not only the almost completely preserved dorsal morphology but, in addition, details of the cephalic appendages, the pereiopods, pleopods and uropods. The presence of ambulatory pereiopods I–VII of a wide tridentate mandibular incisor with prominently developed posteriormost tooth and a narrow frontal lamina indicates that the new species belongs to the subfamily Conilerinae of family Cirolanidae within the suborder Cymothoida. It is closer to the species of the modern genus NatatolanaBruce than to any fossil isopod hitherto described. The isopod fossil record as well as current practices of isopod taxonomy in palaeontology are discussed, and the facies distribution and fossilization of isopods is reviewed with examples from the Jurassic.