High Taxonomic Diversity Research Articles

Shifts in community composition and co-occurrence patterns of phyllosphere fungi inhabiting Mussaenda shikokiana along an elevation gradient.

The altitudinal effects on the distributions of phyllosphere fungal assemblages in conspecific plants remain poorly elucidated. To address this, phyllosphere fungal communities associated with Mussaenda shikokiana were investigated at four sites across a 350 m elevation gradient in a subtropical forest by employing Illumina metabarcoding of the fungal internal transcribed spacer 2 (ITS2) region. Our results demonstrated that phyllosphere fungal assemblages with a single host possessed high taxonomic diversity and multiple trophic guilds. OTU richness was significantly influenced by elevation. The elevation gradient also entailed distinct shifts in the community composition of phyllosphere fungi, which was significantly related to geographical distance and mean annual temperature (MAT). Additionally, comparison of phyllosphere fungal networks showed reduced connectivity with increasing elevation. Our data provide insights on the distribution and interactions of the phyllosphere fungal community associated with a single host along a short elevation gradient.

Diversity and activity of soil fauna in an industrial settling pond managed by natural attenuation

Forest ecosystems can spontaneously establish themselves on former industrial sites contaminated by metals. The sustainable management of these sites by natural attenuation requires a better understanding of the relationships between soil biodiversity, metals and soil functioning in such ecosystems. In this context, a forest ecosystem growing on iron industry by-products containing potentially toxic metals as major elements was studied using a multiproxy approach including chemical soil properties, microstructure, meso- and macro-fauna. Fauna communities in the topsoil were characterized by a high abundance and taxonomic diversity, but also by an unusual predominance of epigeic and detritivorous species. Fauna community structures were partly explained by the presence not only of heavy metals (Zn, Cd), but also Fe and Mn, dominant metals in iron industry by-products. The uncommon structure of macrofauna communities could have effects on the soil functioning, such as limiting the incorporation and mixing of organic matter into the soil. Mesofauna communities contributed to the metal redistribution in the soil by integrating metals into organo-mineral associations. In terms of management, this study showed the feasibility of using natural attenuation to manage sites with high metal contents but low metal availability and favorable conditions for plant growth. However, the influence of soil biota on metal mobility and soil functioning needs to be further investigated in order to assess the sustainability of such management.

Characterization of protistan plankton diversity in ancient salt evaporation ponds located in a volcanic crater on the island Sal, Cape Verde.

Salinity is an important factor when exploring the limits known for life. Therefore, hypersaline systems have attracted much attention in recent years. In this study, we investigated the protistan diversity and community composition in two natural salt evaporation ponds (27-30% salinity) located in an ancient volcanic crater on the Cape Verde island Sal using high-throughput DNA sequencing. Our study revealed a broad range of protistan taxa and a high taxonomic diversity within the Ciliophora, Dinophyceae, and Chlorophyta. We detected a total of 23 Dinophyceae families, although Dinophyceae were generally considered to be only this diverse in aquatic environments of less than 10% salinity. Moreover, we uncovered a high degree of genetic novelty in this habitat. The mean similarity of all detected OTUs to previously described sequences was only 93.6%. These findings strongly dispute the traditional view that extreme hypersaline environments generally maintain low protistan diversity. A meta-analysis covering our and previously published data from other inland and coastal salt ponds clearly showed that our samples clustered according to salinity and not biogeography. This result further supports the claim that salinity is a major transition boundary for protistan communities, regardless of their biogeographic origin.

Influence of commercial DNA extraction kit choice on prokaryotic community metrics in marine sediment

AbstractCommercial DNA extraction kits are widely used for cultivation‐free surveys of marine sediment. However, the consequences of popular extraction‐kit choices for sequence‐based biological inferences about marine sedimentary communities have not previously been exhaustively assessed. To address this issue, we extracted DNA from multiple paired subsamples of marine sediment using two popular commercial extraction kits (MO BIO Laboratories PowerSoil® DNA isolation kit and MP Biomedicals FastDNATM Spin Kit for Soil). We report comparisons of (1) total DNA yield, (2) extract purity, (3) gene‐targeted quantification, and (4) post‐sequencing ecological inferences in near‐seafloor (< 1 meter below seafloor [mbsf]) and subsurface (> 1 mbsf) marine sediment. In near‐seafloor sediment, the MP Biomedicals FastDNATM Spin Kit for Soil exhibits higher extraction yields, higher 16S rRNA gene loads, higher taxonomic diversity, and lower contaminant loads. In subseafloor sediment, both kits yield similar values for all of these parameters. The MO BIO Laboratories PowerSoil® DNA isolation kit generally co‐extracts less protein with the DNA in both near‐seafloor and subseafloor sediment. For samples from all depths, both kits exhibit similar depth‐dependent community richness patterns, taxonomic composition, and ordination‐based similarity trends. We conclude that, despite kit‐specific differences in extract yields, purity and reagent contaminant loads, ecological inferences based on next‐generation sequencing of DNA extracted using these popular commercial kits are robustly comparable, particularly for subseafloor sediment samples.

The Neogene Record of Northern South American Native Ungulates

South America was isolated during most of the Cenozoic, and it was home to an endemic fauna. The South American Native Ungulates (SANUs) exhibited high taxonomical, morphological, and ecological diversity and were widely distributed on the continent. However, most SANU fossil records come from high latitudes. This sampling bias challenges the study of their diversity dynamics and biogeography during important tectonic and biotic events, such as the Great American Biotic Interchange, the faunal exchange between North and South America after the formation of the Isthmus of Panama. We describe new SANU remains from the Neogene of the Cocinetas (northern Colombia) and Falcon (northwestern Venezuela) Basins. In the Cocinetas Basin, the middle Miocene fauna of the Castilletes Formation includes Hilarcotherium miyou sp. nov. (Astrapotheriidae), cf. Huilatherium (Leontiniidae), and Lambdaconus cf. L. colombianus (Proterotheriidae). The late Pliocene fauna of the Ware Formation includes a Toxodontinae indet. and the putative oldest record of Camelidae in South America. In the Falcon Basin, the Pliocene/Pleistocene faunas of the Codore and San Gregorio Formations include Falcontoxodon aguilerai gen. et sp. nov. and Proterotheriidae indet. We provide a phylogenetic analysis for Astrapotheriidae and Toxodontidae. The new data document a low-latitude provinciality within some SANU clades (e.g., Astrapotheriidae, Leontiniidae) during the middle Miocene. This contrasts with the wide latitudinal distribution of clades of other mammals recorded in the fauna, including the sparassodont Lycopsis padillai, the sloth Hyperleptus?, and the proterotheriid Lambdaconus cf. L. colombianus. The Pliocene/Pleistocene tropical faunas from northern South America are characterized by the predominance of native taxa despite their proximity to the Isthmus of Panama (fully emerged by that time). Only one North American ungulate herbivore immigrant is present, a cf. Camelidae indet. The Pliocene and early Pleistocene faunas suggest that environmental changes and biotic interactions affected the diversity dynamics and biogeographic patterns of SANUs during the Great American Biotic Interchange.

Diversity of Heterotrophic Halophilic Bacteria Isolated from Coastal Solar Salterns, Bulgaria and Their Ability to Synthesize Bioactive Molecules with Biotechnological Impact

Investigations on the microbial life in several coastal solar salterns have revealed the presence of novel organisms and synthesis of unusual molecules active in extreme conditions which might be useful in different biotechnological industries. Biodiversity of heterotrophic aerobic bacteria isolated from two salterns, Pomorie salterns and Burgas salterns located at Burgas Bay, Black Sea coast, Bulgaria, as well as ability of the isolates to synthesize biotechnologically valuable compounds were investigated. The results revealed high taxonomic and metabolic bacterial diversity—we isolated 20 morphologically different moderately halophilic and two halotolerant strains affiliated with 11 species from eight genera referred to the phyla Proteobacteria, Firmicutes, and Actinobacteria. Gram-negative bacteria belonged to the genera Halomonas, Chromohalobacter, Salinivibrio, Cobetia, and Nesiotobacter, and gram-positive strains were representatives of the genera Virgibacillus, Salinicoccus, and Brevibacterium. All isolates were found to be alkalitolerant, and 41% of them were psychrotolerant. The strains degraded nine of the tested 18 substrates; polygalacturonase, catalase, phytase, and lipase producers were predominant. This is the first reported detection of xanthan lyase, gellan lyase, arabinase, and phytase activities in halophilic bacteria. Nine of the strains belonging to five different genera were found to produce exopolysaccharides (EPS). The highest level of EPS was observed in Chromohalobacter canadensis strain 28. More than a half of the strains displayed antimicrobial activity against one to five test bacteria and yeasts. The present study is the first report on halophilic bacteria isolated from salterns at the Black Sea coast indicating that the investigated area is an untapped resource of halophilic bacteria with biotechnological potential.

Next Generation Sequencing and mass spectrometry reveal high taxonomic diversity and complex phytoplankton-phycotoxins patterns in Southeastern Pacific fjords

In fjord systems, Harmful Algal Blooms (HABs) not only constitute a serious problem when affecting the wildlife and ecosystems, but also human health and economic activities related to the marine environment. This is mostly due to a broad spectrum of toxic compounds produced by several members of the phytoplankton. Nevertheless, a deep coverage of the taxonomic diversity and composition of phytoplankton species and phycotoxin profiles in HAB prone areas are still lacking and little is known about the relationship between these fundamental elements for fjord ecosystems. In this study, a detailed molecular and microscopic characterization of plankton communities was performed, together with an analysis of the occurrence and spatial patterns of lipophilic toxins in a HAB prone area, located in the Southeastern Pacific fjord region. Microscopy and molecular analyses based on the 18S rRNA gene fragment indicated high diversity and taxonomic homogeneity among stations. Four toxigenic genera were identified: Pseudo-nitzschia, Dinophysis, Prorocentrum, and Alexandrium. In agreement with the detected species, liquid chromatography coupled with mass spectrometry revealed the presence of domoic acid (DA), pectenotoxin-2 (PTX-2), dinophysistoxin-2 (DTX-2), and 13-desmethyl spirolide C (SPX-1). Furthermore, a patchy distribution among DA in different net haul size fractions was found. Our results displayed a complex phytoplankton-phycotoxin pattern and for the first time contribute to the characterization of high-resolution phytoplankton community composition and phycotoxin distribution in fjords of the Southeastern Pacific region.

Constraints on the functional trait space of aquatic invertebrates in bromeliads

Abstract Functional traits are commonly used in predictive models that link environmental drivers and community structure to ecosystem functioning. A prerequisite is to identify robust sets of continuous axes of trait variation, and to understand the ecological and evolutionary constraints that result in the functional trait space occupied by interacting species. Despite their diversity and role in ecosystem functioning, little is known of the constraints on the functional trait space of invertebrate biotas of entire biogeographic regions. We examined the ecological strategies and constraints underlying the realized trait space of aquatic invertebrates, using data on 12 functional traits of 852 taxa collected in tank bromeliads from Mexico to Argentina. Principal Component Analysis was used to reduce trait dimensionality to significant axes of trait variation, and the proportion of potential trait space that is actually occupied by all taxa was compared to null model expectations. Permutational Analyses of Variance were used to test whether trait combinations were clade‐dependent. The major axes of trait variation represented life‐history strategies optimizing resource use and antipredator adaptations. There was evidence for trophic, habitat, defence and life‐history niche axes. Bromeliad invertebrates only occupied 16%–23% of the potential space within these dimensions, due to greater concentrations than predicted under uniform or normal distributions. Thus, despite high taxonomic diversity, invertebrates only utilized a small number of successful ecological strategies. Empty areas in trait space represented gaps between major phyla that arose from biological innovations, and trait combinations that are unviable in the bromeliad ecosystem. Only a few phylogenetically distant genera were neighbouring in trait space. Trait combinations aggregated taxa by family and then by order, suggesting that niche conservatism was a widespread mechanism in the diversification of ecological strategies. A plain language summary is available for this article.

Crescentiella-microbial-cement microframeworks in the Upper Jurassic reefs of the Crimean Peninsula

In the Upper Jurassic reef successions of the Crimean Peninsula (Sudak and Jalta areas), the microencruster Crescentiella morronensis (Crescenti), microbialites, and multiple generations of cements, form microframeworks. They were observed in two stages of the carbonate platform evolution, in the Middle–Upper Oxfordian, and in the Upper Kimmeridgian–Tithonian. Generally, in both stages, the features of the microframeworks are similar and consist of densely packed Crescentiella associated with microbialites and branched colonies of the sclerosponge Neuropora lusitanica Termier. The difference between the occurrences of the two stages is the variable amount of nubecularid foraminifera and enigmatic tube-shaped structures forming the central cavities of Crescentiella. The Crescentiella-microbial-cement microframeworks formed under phreatic conditions in the upper slope and seaward marginal depositional settings where intensive synsedimentary cementation took place. They formed in the initial stages of long cycles of restoration and blooming of the reefs. The late Jurassic examples resemble the Permian algae-microbial-cement reefs as well as the Triassic Tubiphytes and cement crust-dominated reefs. Concurrently, all these examples formed a transitional facies zone between typical slope facies to shallow subtidal platform margin facies characterized by high taxonomic diversity of calcified sponges, corals, and microencrusters forming the principal part of the reefs.

Lower Miocene alligatoroids (Crocodylia) from the Castillo Formation, northwest of Venezuela

Crocodyliform diversity was particularly high during the middle and late Miocene of South America, with up to 12 species recovered from a single geological unit. Nonetheless, the early Miocene fossil record of low-latitude vertebrates is scarce; hence, crocodylians remain poorly known in the region. The Castillo Formation, located in the northwest of Venezuela, preserves an interesting vertebrate fauna with a well-constrained late early Miocene age. Previous work dealing with crocodylians of this formation only recorded three taxa: the gavialoid Siquisiquesuchus venezuelensis and Gryposuchus sp. and indeterminate alligatoroid remains. New cranial and mandibular material recently recovered from the Castillo Formation allows us to document four previously unrecognised alligatoroid forms: Purussaurus sp., Caiman sp., an indeterminate caimanine and an indeterminate alligatoroid. With six taxa, the crocodylian assemblage reveals a previously undocumented relatively high taxonomic diversity in the early Miocene. The Castillo crocodylians show a broad range of morphological disparity and body sizes ranging from small (2.5 m–62 kg) to large (7.5 m–1600 kg) taxa. Thus, crocodylian niche partition, as well as the abundance and variety of resources and environmental heterogeneity of aquatic ecosystems in South America, were already established by at least the early Miocene. The presence of Caiman in ~ 18 Ma strata represents the unequivocally earliest record of the taxon in South America and allows us to propose that the origin of the jacareans is more likely to have occurred during or before the early Miocene, challenging previous molecular hypotheses.

Ectoparasites (Polyctenidae, Streblidae, Nycteribiidae) of bats (Mammalia: Chiroptera) from the Caribbean region of Colombia

Bats are hosts of a high taxonomic diversity of ectoparasites. Six hundred eighty seven insect species have been reported as bat ectoparasites, belonging to orders Dermaptera, Lepidoptera, Diptera and Siphonaptera (Marshall 1982). This study lists an inventory of bat ectoparasites found in fragments of Tropical Dry Forest on the Caribbean coast of Colombia. The study was conducted in the Department of Cordoba in four farms with fragments of Tropical Dry Forest. Bats were captured using mist nets and were collected and stored in plastic bags for subsequent examination in the laboratory. Ectoparasites were stored in alcohol and identified using a stereo microscope and taxonomic keys. Two hundred fifty one bats belonging to 21 species were captured. The most abundant family was Phyllostomidae, followed by Emballonuridae, Noctilionidae, Vespertilionidae and Molossidae. Twelve genera of ectoparasites were found, belonging to families Streblidae, Nycteribiidae and Polyctenidae. Streblidae was the most abundant family and included the largest number of species. Thirty five percent of bats examined were hosts to at least one ectoparasite species. In this study, carried out in fragments of tropical dry forest in Cordoba, Colombia, we recorded dipterans in 17 out of 21 bat species. Hemypteran ectoparasites of the family Polyctenidae were found in Molossus molossus only. Eighty seven individual dipterans were found among 51 Carollia perspicillata specimens, which is consistent with the high parasitism levels previously reported. The bat species C. brevicauda, P. discolor, U. bilobatum and C. perspicillata carried the highest number of ectoparasite species.

Meta-proteomic analysis of protein expression distinctive to electricity-generating biofilm communities in air-cathode microbial fuel cells

BackgroundBioelectrochemical systems (BESs) harness electrons from microbial respiration to generate power or chemical products from a variety of organic feedstocks, including lignocellulosic biomass, fermentation byproducts, and wastewater sludge. In some BESs, such as microbial fuel cells (MFCs), bacteria living in a biofilm use the anode as an electron acceptor for electrons harvested from organic materials such as lignocellulosic biomass or waste byproducts, generating energy that may be used by humans. Many BES applications use bacterial biofilm communities, but no studies have investigated protein expression by the anode biofilm community as a whole.ResultsTo discover functional protein expression during current generation that may be useful for MFC optimization, a label-free meta-proteomics approach was used to compare protein expression in acetate-fed anode biofilms before and after the onset of robust electricity generation. Meta-proteomic comparisons were integrated with 16S rRNA gene-based community analysis at four developmental stages. The community composition shifted from dominance by aerobic Gammaproteobacteria (90.9 ± 3.3%) during initial biofilm formation to dominance by Deltaproteobacteria, particularly Geobacter (68.7 ± 3.6%) in mature, electricity-generating anodes. Community diversity in the intermediate stage, just after robust current generation began, was double that at the early stage and nearly double that of mature anode communities. Maximum current densities at the intermediate stage, however, were relatively similar (~ 83%) to those achieved by mature-stage biofilms. Meta-proteomic analysis, correlated with population changes, revealed significant enrichment of categories specific to membrane and transport functions among proteins from electricity-producing biofilms. Proteins detected only in electricity-producing biofilms were associated with gluconeogenesis, the glyoxylate cycle, and fatty acid β-oxidation, as well as with denitrification and competitive inhibition.ConclusionsThe results demonstrate that it is possible for an MFC microbial community to generate robust current densities while exhibiting high taxonomic diversity. Moreover, these data provide evidence to suggest that startup growth of air–cathode MFCs under conditions that promote the establishment of aerobic–anaerobic syntrophy may decrease startup times. This study represents the first investigation into protein expression of a complex BES anode biofilm community as a whole. The findings contribute to understanding of the molecular mechanisms at work during BES startup and suggest options for improvement of BES generation of bioelectricity from renewable biomass.

Taxonomic and ecological variations of Permian-Triassic transitional bivalve communities from the littoral clastic facies in southwestern China

Immediately after the latest Permian mass extinction, bivalve faunas colonized the Permian-Triassic Transitional Beds (PTTB), especially in littoral clastic facies of South China. The Permian-Triassic (P-Tr) transitional bivalve fauna is composed of holdovers, long-term survivors and newly evolved taxa, and characterized by moderate diversity and high dominance. However, the taxonomy and ecology of this bivalve fauna of littoral clastic facies have not been well understood, especially in comparison with offshore marine records. This paper presents a study on a P-Tr transitional bivalve fauna from five sections of littoral clastic facies in southwestern China, and as such it contributes to a better knowledge of the ecological processes of benthic communities during the P-Tr transition. In total, 20 species in 13 genera of bivalves are identified from the PTTB in the lower part of the Kayitou Formation and the basal part of the Feixianguan Formation of the five sections. Cluster analysis suggests that the transitional bivalve fauna could be further divided into two successive communities (early and late communities), and each is composed of five assemblages. Promyalina–Neoschizodus community (early community) is characterized by presence of holdover taxa, high taxonomic diversity and evenness, and more abundant shallow infaunal suspension feeders. In Pteria community (late community), taxonomic diversity and evenness are much lower, and stationary epifaunal suspension feeders boost at the expense of shallow infaunal suspension feeders compared with the Promyalina–Neoschizodus community. Furthermore, the Promyalina–Neoschizodus community shows a clear spatial variation along environmental gradient from brackish lagoon to shallow marine settings, while the Pteria community is more uniform and homogeneous laterally. The Promyalina–Neoschizodus community in the studied region is of latest Permian age while the Pteria community should belong to the earliest Triassic. Consequently, a significant taxonomical and ecological turnover of bivalve communities occurred between the Promyalina–Neoschizodus community and the Pteria community during the extinction interval in southwestern China.

Response of benthic invertebrate communities to a land use gradient in tropical highland streams in Nigeria

Benthic invertebrate communities have been shown to respond to habitat degradation as a result of land use changes. Although these changes have been well documented in temperate regions, their effects in the tropics have been poorly documented particularly where land use activities differ markedly (e.g., tea, maize and plantations). A survey 55 1st and 2nd order highland tropical streams, across four land use categories, ranging from continuous tropical montane rain forest to intensive crops and pasture. Streams were sampled in the tropical dry season (October–March) for physico-chemical parameters and components of the biological community, (i.e., fine particulate organic matter [FPOM], coarse particulate organic matter [CPOM], algae and benthic invertebrates). Catchment riparian conditions and human water use activities were used to generate a multivariate land use intensity gradient score. Temperatures in pasture streams were warmer than forest streams (up to 25oC) and dissolved oxygen levels frequently low (15–79%). However, physico-chemical conditions did not show any clear patterns across land uses categories. In contrast, benthic invertebrate communities showed strong response with the highest taxonomic diversity in continuous forest streams (mean 20 taxa) and the lowest in streams with intensive crops (e.g., cabbage crops, mean 8 taxa). Marked changes were found in invertebrate communities with several taxa occurring primarily in forested streams (e.g., the mayflies Heptageniidae and Oligoneuriidae and brachyuran crabs). Tropical land use farming (e.g., tea, maize, cabbage) have significant impacts on the benthic invertebrate assemblages of highland streams in Nigeria. However, not all crop and plantation streams had highly impacted communities because some have wider riparian buffer zones. This study further highlight the importance of conservation and management of montane forest fragments in these regionsKeywords: Tropical, Nigeria, highland, benthic invertebrates, land use, degradation

Flightless rails (Aves: Rallidae) from the early Miocene St Bathans Fauna, Otago, New Zealand

While known for over a decade to exist, fossil rails of the early Miocene (19–16 Ma) St Bathans Fauna, from the South Island of New Zealand, have not previously been described taxonomically or studied in detail. Here we use qualitative osteological features and analyse measurements from wing and leg bones to determine the number of taxa represented, their flight ability, and the presence and nature of sexual dimorphism within the identified taxa. We describe two new rail species in monospecific genera from the St Bathans Fauna: Priscaweka parvales gen. et sp. nov., which is extremely common, and Litorallus livezeyi gen. et sp. nov., a distinctly larger, uncommon species. Priscaweka parvales exhibited a significant degree of sexual dimorphism and was tiny, being the size of the extinct Chatham Island Rail Cabalus modestus. Both newly described species exhibit skeletal proportions and osteological features that indicate they had reduced wings and were flightless. These observations reveal that flightless rallid species have been present in New Zealand for millions of years. The distinctiveness of the St Bathans rails from their closest geographical and chronological neighbours suggests some hidden diversity of volant rails in Australia's fossil record. However, the combined data from Australasian and European records reveal no evidence for a diverse early Miocene crown rallid fauna as predicted by some molecular studies. A subsequent, middle Miocene radiation for crown rallids seems more likely, and appears to have produced the high taxonomic diversity seen in Holocene Australasian rail faunas.http://zoobank.org/urn:lsid:zoobank.org:pub:9F638A1E-C17D-4A85-9D6E-3D0F24D5AE1E

On the "Seidenfaden collection" and the multiple roles botanical gardens can play in orchid conservation

Abstract. Using the in Copenhagen as an example, we address the common view that botanical garden collections of orchids are important for conservation. Seidenfaden collected live orchids all over Thailand from 1957 to 1983 and created a traditional collection for taxonomic research, characterized by high taxonomic diversity and low intraspecific variation. Following an extended period of partial neglect, we managed to set up a five-year project aimed at expanding the collection with a continued focus on taxonomic diversity, but widening the geographic scope to tropical Asia. Since its establishment, the collection has contributed significantly to ex situ conservation and to research-based development of powerful tools for improving in situ conservation-related decisions and priorities. The collection has been, and still is, an important basis for taxonomic and floristic research which has enabled treatment of the Orchidaceae in the Thai red-list. However, the primary focus of our project has shifted to micro-propagation, DNA-barcoding and phylogenetic analysis. The close link between collection-based research and conservation is remarkable and probably applicable to plant collections in botanical gardens in general. Thus, if the collections are used properly, they have great potential for contributing to conservation in many different ways.

A taxonomic, functional, and phylogenetic perspective on the community assembly of passerine birds along an elevational gradient in southwest China.

Integrating multiple facets of biodiversity to describe spatial and temporal distribution patterns is one way of revealing the mechanisms driving community assembly. We assessed the species, functional, and phylogenetic composition and structure of passerine bird communities along an elevational gradient both in wintering and breeding seasons in the Ailao Mountains, southwest China, in order to identify the dominant ecological processes structuring the communities and how these processes change with elevation and season. Our research confirms that the highest taxonomic diversity, and distinct community composition, was found in the moist evergreen broadleaf forest at high elevation in both seasons. Environmental filtering was the dominant force at high elevations with relatively cold and wet climatic conditions, while the observed value of mean pairwise functional and phylogenetic distances of low elevation was constantly higher than expectation in two seasons, suggested interspecific competition could play the key role at low elevations, perhaps because of relative rich resource result from complex vegetation structure and human‐induced disturbance. Across all elevations, there was a trend of decreasing intensity of environmental filtering whereas increasing interspecific competition from wintering season to breeding season. This was likely due to the increased resource availability but reproduction‐associated competition in the summer months. In general, there is a clear justification for conservation efforts to protect entire elevational gradients in the Ailao Mountains, given the distinct taxonomic, functional, and phylogenetic compositions and also elevational migration pattern in passerine bird communities.

High-diversity European palaeoflora favoured by early Pliocene warmth: New chronological constraints from the Ca′ Viettone section, NW Italy

We present new chronological constraints for a reference European palaeoflora based on integrated stratigraphic, palaeobotanical, palaeomagnetic and micropalaeontological analysis carried out on the Pliocene section of Ca′ Viettone, northwestern Italy. This site is characterized by rich fossil plant records of high taxonomic diversity, good preservation, and varied taphonomic mode. Palaeofloral analysis shows that the Ca′ Viettone assemblage reflects a chronologically delimited and distinguishable stage of vegetation development in northern Italy (called Ca′ Viettone Florenkomplex). Palaeomagnetic analyses show a dominant normal polarity that, however, seems to be the result of a remagnetization process due to secondary oxidation. Layers with no evidence of oxidation have registered a reverse polarity, which likely represents the original magnetization of the sediments. These results, in combination with biochronological indications, suggest that deposition of the succession preceded the Gilbert-Gauss reversal and took place during the final part of the Gilbert chron. This confirms a late Zanclean age for the rich Ca′ Viettone palaeoflora and allows us to propose this locality both as reference for a regional Florenkomplex and as a representative example of terrestrial vegetation in Europe during the early Pliocene warm interval.

Déterminants de la structure des communautés fongiques dans les forêts de Corse : rôle des perturbations et de la composition forestière

L’étude de l’écologie des micro-organismes est récente malgré son importance pratique et théorique intrinsèque, mais également son rôle central dans la niche des macro-organismes. Les interactions plantes-champignons, de par leur importance socio-écologique et leur diversité — du mutualisme au parasitisme en passant par le commensalisme —, offrent un modèle judicieux pour étudier l’écologie des communautés de micro-organismes en interaction avec des macro-organismes. À l’aide de techniques de séquençage à haut débit (NGS) et d’analyse des réseaux, nous explorons certains déterminants de la structure des champignons des forêts de Corse à travers trois guildes : les champignons ectomycorhiziens, endophytiques et saprotrophes. Ce travail considère les processus de dispersion, les perturbations (feux et chablis), les facteurs environnementaux (par exemple la profondeur du sol) et les contraintes dérivées de l’interaction avec les hôtes (par exemple la taxinomie). Les assemblages des communautés des différentes guildes présentent des patrons communs qui pourraient être issus de mécanismes identiques. Ainsi, l’ensemble des guildes étudiées présentent des variations fortes à l’échelle des microrégions de Corse et entre forêts ayant des histoires de feux différentes. En revanche, l’importance des différents processus d’assemblage et les échelles spatiales auxquelles ils s’appliquent varient selon les guildes. Nous discutons des implications que suscite ce travail pour les écologues des communautés et pour les gestionnaires d’espaces naturels.

CORAL COMMUNITIES, ZONATION AND PALEOECOLOGY OF AN UPPER JURASSIC REEF COMPLEX (ELLIPSACTINIA LIMESTONES, CENTRAL APENNINES, ITALY)

This work describes and analyzes an original collection of fossil corals from the Ellipsactinia Limestones (Kimmeridgian-Tithonian), exposed in the Marsica area (central Apennines, Italy), focusing on taxonomy and paleoecology. 43 species grouped into 32 genera, 16 families and 9 suborders were identified. Astreoidogyra giadae nov. gen. nov. sp. (Rhipidogyridae) and Clausastrea eliasovae nov. sp. (Montlivaltiidae) are new taxa. Corals occur from the back reef to the reef crest, showing a marked zonation, expressed by a variation of coral cover and type, although the reef front and slope facies could not be sampled. The back reef is characterised by scattered medium-to-small colonies, with a relative high variety of colony shape, corallite arrangement types and high taxonomic diversity. Stylosmilia, Calamophylliopsis, Intersmilia, Pleurophyllia, Bracthelia, Heliocoenia, Ogilvinella occur here among others. The inner reef flat records the highest coral cover, with large robust branching, such as “Pseudocoenia”, Heliocoenia, Calamophylliopsis, and large dome-shaped meandroid, such as Psammogyra, Pruvostrastraea, Eugyriopsis) colonies. Within the external reef flat and the reef crest the coral cover is low and the stromatoporoid-bearing mounds dominate on the isolated coral bioconstructions. Controlling factors as bathymetry, hydrodynamic disturbances, abrasive currents, background sedimentation and morphological irregularities of the depositional profile are considered to explain the observed coral zonation. High diversity and low dominance indices are interpreted to result from reef complex heterogeneity, which should have influenced the formation of different ecological niches and consequently the proliferation of a greater number of taxa in a relatively small area.