Diverse Assemblage Research Articles

Establishment and range expansion of invasive Cactoblastis cactorum (Lepidoptera: Pyralidae: Phycitinae) in Texas

Abstract Invasive species are a leading cause of global biodiversity decline. Larvae of the cactus moth Cactoblastis cactorum Berg (Lepidoptera: Pyralidae: Phycitinae) consume prickly pear cactus species (Opuntia; Cactaceae) in its native South American range. High host specificity made C. cactorum an appropriate biological control agent of Opuntia species, which have become invasive weeds around the world. This biological control program was successful. Ironically, the success of cactus weed biological control facilitated a series of events which led to C. cactorum invasion of North America where Opuntia diversity is tremendous. In 2017, C. cactorum established along the southeast Texas coast. In 2020, we began monitoring C. cactorum dispersal towards south and south-west Texas with cactus moth pheromone traps. Our objectives were to document the extent of the invasion and calculate dispersal rates towards commercial Opuntia-growing regions in Mexico. There are four overlapping moth flight peaks in Texas. Between 2017 and 2022, the C. cactorum populations invaded over 27,000 km2 in south-east and south-central Texas at a dispersal rate up to 47 km year. Since 2022, this dispersal rate slowed as the moth invasion front came into contact with the Tamaulipan thornscrub region of south Texas where Opuntia density is high and native cactus moth species are attacked by a diverse assemblage of parasitoids. We present data on the density of native cactus moth species in Texas which shows that their density increases west and south-west of the area currently occupied by C. cactorum. These data suggest that apparent competition may be occuring between C. cactorum and native cactus moth species via shared parasitoids. This hypothesis is not mutually exclusive of other biological barriers that may contribute to explaining why the Texas C. cactorum dispersal rate has slowed significantly. We conclude with a discussion about how to leverage these data to support future deployment of C. cactorum biological control agents in Texas.

HERPETOFAUNAL REMAINS (ANURA, CROCODYLIA, TESTUDINES, SQUAMATA) FROM THE LATE MIOCENE OF THE CREVILLENTE AREA (SE SPAIN): PALAEOBIOGEOGRAPHICAL AND PALAEOECOLOGICAL IMPLICATIONS

In the present work we describe the palaeoherpetofaunal remains from the Crevillente 2 (MN11) and Crevillente 15 (MN12) sites (Crevillente, Alicante, Spain), which is a key area for understanding the faunal turnovers during the Late Miocene. Crevillente 2 has yielded a diverse assemblage composed of anurans (Pelophylax sp.), crocodylians (Crocodylia indet.), lizards (cf. Scinciformata indet. 1 and 2, cf. Timon sp., Lacertidae indet. 1 and 2, Ophisaurus s.l. sp., and Pseudopus sp.) and ophidians (Colubridae indet. 1 and 2, Neonatrix sp., and Viperidae indet. Oriental morphotype). The probable presence of Timon is discussed; if confirmed, it would be the oldest occurrence of the genus. The faunal composition is consistent with that from other coeval Iberian sites. The assemblage includes European autochthonous taxa (Lacertidae and Ophisaurus s.l. sp.) and taxa that likely arrived from Asia or North America during the Oligocene-Miocene transition or the Early Miocene, such as Pseudopus, Oriental vipers and, probably, Neonatrix. The studied assemblage in Crevillente 15 is limited to turtles (Paleotestudo sp. and Testudines indet.) and crocodylians (Crocodylia indet.). At both localities, the surrounding landscape must have been dominated by open habitats with patches of forest/shrubland formations close to water bodies. The application of the Herpetological Ecophysiological Groups method to Crevillente 2 indicates that the mean annual rainfall must have been higher than currently recorded in the area. the Herpetological Ecophysiological Groups method to Crevillente 2 indicates that the mean annual rainfall must have been higher than that currently recorded in the area. Our results indicate that the Iberian palaeoherpetofauna of those chronologies were few barely affected by the Vallesian Crisis.

Asynchronous effects of heat stress on growth rates of massive corals and damselfish in the Red Sea.

Climate change is imposing multiple stressors on marine life, leading to a restructuring of ecological communities as species exhibit differential sensitivities to these stressors. With the ocean warming and wind patterns shifting, processes that drive thermal variations in coastal regions, such as marine heatwaves and upwelling events, can change in frequency, timing, duration, and severity. These changes in environmental parameters can physiologically impact organisms residing in these habitats. Here, we investigate the synchrony of coral and reef fish responses to environmental disturbance in the Red Sea, including an unprecedented combination of heat stress and upwelling that led to mass coral bleaching in 2015. We developed cross-dated growth chronologies from otoliths of 156 individuals of two planktivorous damselfish species, Pomacentrus sulfureus and Amblyglyphidodon flavilatus, and from skeletal cores of 48 Porites spp. coral colonies. During and immediately after the 2015 upwelling and bleaching event, damselfishes exhibited a positive growth anomaly but corals displayed reduced growth. Yet, after 2015-2016, these patterns were reversed with damselfishes showing a decline in growth and corals rebounding to pre-disturbance growth rates. Our results reveal an asynchronous response between corals and reef fish, with corals succumbing to the direct effects of heat stress, and then quickly recovering when the heat stress subsided-at least, for those corals that survived the bleaching event. Conversely, damselfish growth temporarily benefited from the events of 2015, potentially due to the increased metabolic demand from increased temperature and increased food supply from the upwelling event, before declining over four years, possibly related to indirect effects associated with habitat degradation following coral mortality. Overall, our study highlights the increasingly complex, often asynchronous, ecological ramifications of climate extremes on the diverse species assemblages of coral reefs.

Floodplain forests drive fruit-eating fish diversity at the Amazon Basin-scale

Unlike most rivers globally, nearly all lowland Amazonian rivers have unregulated flow, supporting seasonally flooded floodplain forests. Floodplain forests harbor a unique tree species assemblage adapted to flooding and specialized fauna, including fruit-eating fish that migrate seasonally into floodplains, favoring expansive floodplain areas. Frugivorous fish are forest-dependent fauna critical to forest regeneration via seed dispersal and support commercial and artisanal fisheries. We implemented linear mixed effects models to investigate drivers of species richness among specialized frugivorous fishes across the ~6,000,000 km2 Amazon Basin, analyzing 29 species from 9 families (10,058 occurrences). Floodplain predictors per subbasin included floodplain forest extent, tree species richness (309,540 occurrences for 2,506 species), water biogeochemistry, flood duration, and elevation, with river order controlling for longitudinal positioning along the river network. We observed heterogeneous patterns of frugivorous fish species richness, which were positively correlated with floodplain forest extent, tree species richness, and flood duration. The natural hydrological regime facilitates fish access to flooded forests and controls fruit production. Thus, the ability of Amazonian floodplain ecosystems to support frugivorous fish assemblages hinges on extensive and diverse seasonally flooded forests. Given the low functional redundancy in fish seed dispersal networks, diverse frugivorous fish assemblages disperse and maintain diverse forests; vice versa, diverse forests maintain more fish species, underscoring the critically important taxonomic interdependencies that embody Amazonian ecosystems. Effective management strategies must acknowledge that access to diverse and hydrologically functional floodplain forests is essential to ensure the long-term survival of frugivorous fish and, in turn, the long-term sustainability of floodplain forests.

Seasonal Variation of Epipelic Diatom Assemblages and Their Relationships with Abiotic Variables in the Utility and Drinking Water Source of İstanbul: Büyükçekmece Reservoir

In this study, the distribution and composition of epipelic diatoms in Büyükçekmece Reservoir, which is one of the most important and main freshwater resources for İstanbul, Türkiye were investigated seasonally. Epipelic diatom samples were collected from five different stations each season (February, May, August, and November) in 2019. A total number of eighty-seven taxa belonging to thirty-seven genera were identified, six of which were centric and eighty-one were pennate; five of the epipelic species were new record diatoms for the Büyükçekmece Reservoir. The highest number of epipelic diatom species were encountered in February while the lowest was in November. Considering the frustule counts, it was observed that the species that increased their relative abundance changed in each sampling period. Consequently, it was observed that Gomphonella olivacea was the most abundant in February, Navicula reichardtiana in May, Achnanthidium sp. in August, and Cocconeis placentula in November. Shannon-Weaver Diversity Index showed that the highest diversity of diatom species was determined in February (station 4), and the lowest was observed in August (station 3). According to the results of redundancy analysis, it was observed that silicate-Si, conductivity, and temperature were the most efficient variables in the distribution of the epipelic diatom species.

Identification of deposits from modern and ancient large tsunamis by means of environmental DNA

We examined the potential of environmental DNA (eDNA) for identifying tsunami deposits in the geological record using lake-bottom sediments in the Tohoku region, Japan. The presence of eDNA from marine organisms in a lacustrine event deposit provides very strong evidence that the deposit was formed by an influx of water from the ocean. The diverse DNA assemblage in the deposit formed by the 2011 Tohoku-oki tsunami included DNA of marine origin indicating that eDNA has potential as an identifying proxy for tsunami deposits. Subsequently, we examined the applicability of eDNA for recognizing paleo-tsunami events using the deposits formed by the 869 CE Jogan tsunami and a prehistoric event (2400–2900 cal year BP). The taxa detected in the tsunami deposits were markedly different from those of the background sediments. Many taxa that were represented in the Jogan tsunami deposit were also detected in the layer immediately above the tsunami deposit. This layer was indistinguishable from the overlying peat by visual observation, but the eDNA results suggest that it is likely to be a muddy tsunami deposit. The results of this study indicate that eDNA has the potential to elucidate the origin of event deposits that have been difficult to identify.

How Does Landscape Structure Affect Dung Beetle Assemblages in Amazon Cities?

The growth of cities is one of the main direct and indirect factors responsible for the loss of native vegetation cover. Urbanization directly affects the biological communities inhabiting forest remnants inserted in cities, compromising the maintenance of urban and natural ecosystems. By understanding the effects of landscape transformation due to urbanization, we can have insights regarding the distribution of land uses that allow a proper maintenance of the urban ecosystems. This work assessed the effects of landscape structure variables (forest cover, agricultural area, edge density, and number of forest patches) on dung beetle assemblages and functional groups (i.e., diet and resource removal strategy) sampled in 38 sites located along an urban-rural gradient of six cities belonging to the metropolitan area of Manaus in Central Amazonia. Losses of forest cover were the most determining factor, negatively affecting species richness, abundance, and body size. The increases in agriculture cover negatively affected dung beetle abundance, while edge density positively affected their abundance. The number of forest patches positively affected dung beetle abundances-except for dweller species-and negatively affected the body size of diet-generalist species. These results demonstrate that changes in ecological diversity caused by urbanization are driven mostly by forest cover loss, although forest configuration is important for dung beetle abundance. This study contributes to the understanding of how changes in the amount and distribution of forest cover in tropical cities affect the taxonomic diversity of dung beetle assemblages.

Biodiversity accounting on farms: Relating diversity of bird assemblages to ecosystem condition.

Natural capital accounting can help farmers and producers meet global demands to disclose supply chain impacts on biodiversity and to reverse biodiversity declines in farmland. To date, methods have been limited in their ability to reliably represent biodiversity, especially fauna, and are typically prepared at the regional scale, not at the farm scale - the scale at which many decisions that impact habitats for species are made. We surveyed birds at 1155 sites across 50 farms (total area=135,890ha) in south-eastern Australia to relate site-level species richness of groups of birds to spatially discrete ecosystem condition states that are based on the structure and composition of vegetation and to develop a framework for farm-scale biodiversity accounting. Site-level species richness of bird groups was strongly related to ecosystem states. Spatially explicit models enabled calculation of the proportion of a farm that provides high-quality habitat for each bird group. This metric represents farm-level diversity and can be used to quantify a farm's impact on biodiversity and contribution to biodiversity conservation. This approach could be applied to agriculture regions within Australia and could be replicated in agricultural landscapes around the world where it is possible to establish applicable state and transition models with a reliable 'best-on-offer' or 'reference' condition state. Farm-scale accounts that incorporate biodiversity provide a robust tool for strategic farm management, rigorous environmental reporting, greater traceability through supply chains, and improved access to global sustainability markets.

Biodiversity spatial distribution of benthic macroinvertebrate assemblages is influenced by anthropogenic disturbances at multiple spatial extents.

Understanding the patterns and mechanisms of biodiversity and its organization in space is essential for developing effective conservation strategies. Zeta diversity is an index of how taxa are shared by several sites, providing information on how ecological filters, including anthropogenic disturbances, influence biodiversity distribution. This study documents how anthropogenic disturbances at multiple spatial extents affect the spatial variation of benthic macroinvertebrate assemblages in lotic ecosystems. To test the relation between zeta diversity and anthropogenic disturbances, we used three disturbance metrics. (a) For in-stream disturbances, we used the percentage of fine sediment in the substrate (PCT_FN). (b) For local/riparian disturbances, we used the Local Disturbance Index (LDI). (c) For catchment disturbances we used the Catchment Disturbance Index (CDI). Our results showed that differing anthropogenic disturbances were differently important for spatial biodiversity variation in benthic macroinvertebrate assemblages. Relatively rarer taxa were usually more susceptible to in-stream and local/riparian-scale disturbances or local environmental filters. On the other hand, relatively common taxa were usually more related to catchment-scale disturbances or landscape resistance to dispersal. These results indicate that conservation efforts to maintain headwater ecosystem biodiversity must incorporate multiple spatial extents because relatively rare and relatively common taxa appear to be affected to different degrees by different anthropogenic disturbances at different spatial extents.

Elemental Substitution and Compositional Evolution of Tourmaline and Dumortierite Formation in Muscovite-schist Rock of Sakoli Area in Bhandara District, Central India

ABSTRACT Paleoproterozoic metapelitic schistose rocks are closely associated with the tourmaline deposit in the Girola area of the Sakoli Group of rocks of the Central India Tectonic Zone (CITZ). In this area, shear zones have effectively played a significant role in the formation and distribution of tourmaline along with hosts of minerals like garnet, sillimanite, dumortierite, etc. Local tourmaline concentrations can be found within quartz mylonites, granite mylonites, phyllonites, etc. wherein they are present as solitary crystal clusters, or discontinuous tourmaline bands or pockets. Mineralogical and chemical changes have been documented within these rocks in Girola Hill. The preliminary study had indicated the presence of tourmaline varieties, namely- schorl, dravite, foitite, elbite, liddicoatite, dumortierite, along with sillimanite, muscovite, sericite, rutile, topaz, and corundum. The presence of apatite, Sr-phosphate, and fluorite was also noticed. Within the assemblage zone, variations in boron metasomatism and potash leaching appear to be regulating variations in mineral assemblages and overall rock chemistry. Magmatic-metasomatic fluids have partially altered the original sedimentary patterns, according to the elemental analysis of the materials. The alteration could be due to interactions of schists with B-, F-carrying fluid. Tourmaline-rich assemblages develop when the fluid’s boron reacts with the nearby schistose rocks, leading to sheet silicate to cease functioning as a trap for Na, K, and Ba. Further metasomatic activity results in the formation of dumortierite from the tourmaline assemblages.

Quantitative Approach for Determining Reproductive Life-History Strategies of Parasitic Plants: A Case Study in Balanophora.

Parasitic plants are a diverse and unique polyphyletic assemblage of flowering plants that survive by obtaining resources via direct vascular connections to a host plant. Ecologically important in their native ecosystems, these typically cryptic plants remain understudied and fundamental knowledge of the biology, ecology, and evolution of most species is lacking. This gap limits our understanding of ecosystems and conservation management. We established a multistep protocol to conduct the first investigation of the reproductive life history of root parasite genus Balanophora, testing the hypotheses of perenniality, cryptic perenniality, and plasticity across five geographically isolated populations in Taiwan. A review of 123 Balanophora publications found contradictory determinations, including no determination (87%), perennial (9%), annual (1%), biennial (1%), or a combination (2%). No primary study investigated the question, and no determination was accompanied by reference. Between 2021 and 2024, we tested a hypothesis of perenniality (109 individuals, 135 patches) and cryptic perenniality (73 host samples), monitored population dynamics (whole population), and potential for endophytic/dormant haustorial tissue (101 roots) across five isolated populations of Balanophora fungosa ssp. fungosa in Taiwan. Our results support semelparous annuality. After reproduction, individuals senesce and die, and the following year's population is recruited from newly germinated individuals which together develop in size and number during a vegetative growth period, undergo reproduction, and then themselves senesce and die. Each cycle is completed within a 12-month period. Synthesis: Our study provides the first quantitative determination of a semelparous annual reproductive life-history strategy for any species of Balanophora. This determination is important in our progress toward better understanding the species-and parasitic plants in general-as well as ecological roles within ecosystems and conservation management. Our study further provides a template for future work to expand life-history strategy determination across cryptic root parasitic plants.

Diversity and future perspectives of Mediterranean deep-water oyster reefs

Anthropogenic and climate factors are increasingly affecting the composition and functions of many marine biogenic reefs globally, leading to a decline in associated biodiversity and ecosystem services. Once dominant ecological component, modern oyster reefs in the Mediterranean and Black Sea and the Atlantic Ocean have already been profoundly altered by overharvesting, habitat loss and the introduction of alien species. Far less known are deep-water oyster reefs, which can however form substantial biogenic structures below 30 m depth. Here we analyze the diversity of benthic assemblages associated with deep-water oyster reefs formed by the gryphaeid Neopycnodonte cochlear, and other mesophotic habitats in the central Mediterranean Sea using a taxonomic and functional approach. Our findings suggest that deep-water oyster reefs may act as hotspots of biodiversity and ecological functions in the Mediterranean Sea under current conditions, having also an edge in survival in a changing ocean.

A comprehensive RNA virome identified in the oyster Magallanagigas reveals the intricate network of virus sharing between seawater and mollusks

BackgroundAs a globally farmed oyster species, Magallana gigas has garnered significant attention due to the contaminated RNA viruses that have caused illness in humans. However, limited knowledge is available on the bioaccumulation status and overall diversity of RNA virome in the M. gigas digestive tissues (DTs). Moreover, there is a lack of understanding regarding the shared community of RNA virome among intertidal mollusks. To address these knowledge gaps, we performed a comprehensive meta-transcriptomic analysis of 173 M. gigas samples from the East China Sea and compared the viral sequences to the meta-transcriptomes of other mollusks and seawater (i.e., the oyster Magallana hongkongensis, bivalves, gastropods, cephalopods, and Yangshan Harbor) through RdRP identification and reads mapping.ResultsOur results indicate that 154 viral RdRPs were confidently identified in the M. gigas DT, with 94% (144/154) showing less than 90% amino acid identity. This indicates the presence of at least 144 putative novel RNA virus species in M. gigas DT. All viruses belonged to the phyla Lenarviricota, Pisuviricota, and Kitrinoviricota, and the marna-like viruses constituted the most diverse assemblage among these newly identified viruses. Furthermore, members of marna-like, picobirna-like, and noda-like virus groups comprise the most prevalent viruses in the M. gigas meta-transcriptome, with 14 RdRP-bearing sequences accounting for at least 1% of the overall aligned reads. M. hongkongensis has been found to harbor the most diverse viruses found in M. gigas, while 37 and 25 newly identified RNA viruses in oysters were discovered in an octopus meta-transcriptome and seawater virome, respectively.ConclusionsThe findings provide insights into the cryptic and hitherto unstudied virus-sharing network across the marine food web. Moreover, the viruses identified in oysters have the potential to serve as indicators for identifying the circulation of marine RNA viruses.CHfVwvqMzd5A-E5eqpdjTsVideo

How multi-species pollination boosts strawberry yield, quality, and nutritional value

A diverse assemblage of insect visitors can provide functional complementarity within plant pollination due to differences in characteristics such as their physical traits, visitation rate and foraging time of day or year. In a horticultural context, greater functional complementarity may play a crucial role in enhancing fruit yield and quality by improving pollination. We tested whether the identity of the crop pollinators (bumblebee Bombus terrestris and hoverfly Eupeodes corollae) independently and additively influenced commercial strawberry yield, quality, and nutritional parameters such as vitamin C and sugar concentration. Fragaria x ananassa “Malling Champion” plants received pollination treatments of either a) “control”: self-pollination where pollinators were excluded, b) “bee”: bumblebee Bombus terrestris, c) “hoverfly”: Eupeodes corollae, d) “combined”: both B. terrestris and E. corollae. Hoverflies and bumblebees exhibited distinct visitation patterns throughout the day, establishing a functional complementary relationship that enhances pollination success and crop output as well as vitamin C concentrations. Strawberries from plants receiving pollination by bumblebees, or bumblebees and hoverflies combined, had higher yields of higher marketable quality. They also had measurably higher vitamin C content than strawberries from plants pollinated by hoverflies alone, or the control (self-pollinating) plants. This study advances our understanding of niche complementarity and its impact on fruit yield and quality. By elucidating the behavioural and temporal dynamics of pollinators, we provide valuable insights for optimizing pollination strategies in agricultural contexts. Our findings highlight the significance of behavioural factors, such as handling time and number of visits, in determining fruit quality.

Phytoliths in dicotyledons occurring in North-western Europe: Establishing a baseline.

The absence of a modern plant-based 'dicotyledon' phytolith reference baseline impedes the accurate interpretation of fossil phytolith records in archaeological and palaeoecological research within North-western Europe. This study aims to fill this gap by documenting and analysing the phytolith record from modern dicotyledon taxa occurring in this region. Phytoliths were extracted from several plant parts of 117 plant specimens representing 74 species (1-2 specimens/species). The study employed light microscopy to examine phytolith production (non-producer, trace, common, or abundant) and phytolith assemblage composition. The data were analysed statistically to (a) determine the influence of taxonomy and plant part on phytolith presence (absent/present) using a Mixed Model, (b) assess phytolith assemblage variation using a Permutational Multivariate Analysis of Variance (PerMANOVA), and (c) identify patterns among sample groups including segregation for plant part, life form (forbs vs shrubs/trees), and order using a Linear Discriminant Analyses (LDA). Morphotype analysis reveals diagnostic morphotypes and features for specific plant families, genera, and plant parts. LDA effectively segregated plant parts and life forms, though taxonomic groupings showed limited segregation. Phytolith presence (absent/present) was found to vary, influenced by both plant part and taxonomy. For species examined through two specimens, although phytolith production varied considerably, phytolith assemblage composition was consistent. This study establishes a 'dicotyledon' phytolith baseline for North-western Europe, showing that the phytolith record can be informative in terms of plant part and life form and that several phytolith morphotypes and/or features are taxonomically diagnostic below 'dicotyledon' level. The findings constitute a foundation upon which future research can build, refining and expanding our knowledge of the North-western European region.

Conodont stratigraphy and biodiversity of the Middle Devonian Kačák Episode at the Pic de Bissous (Montagne Noire, S-France)

AbstractPic de Bissous belongs to classic sections of the latest Eifelian Kačák Episode (KE) interval, uniquely developed in hemipelagic carbonate facies. The present conodont study is based on dense sampling of the section, yielding rich and diverse assemblages dominated by Polygnathus. The position of the lower and upper KE boundaries is here documented within the upper Eifelian kockelianus Zone and at the base of the lowermost Givetian hemiansatus Zone, respectively. Both boundaries are marked by an increase of P1 elements diversity, the phenomenon reported also from other palaeogeographic setting, and accompanied by an appearance of several new taxa. This suggests a global two-step conodont biodiversity rise around the KE interval, presumably caused by the eustatic If and earliest Givetian sealevel rises, respectively. These events were accompanied by increased juvenile conodont mortality probably due to some local/regional adverse conditions of either abiotic or biotic nature.

Invasive Buffelgrass, Cenchrus ciliaris, Balances Opportunistic Acquisition of Foliar fungi With Host and Environmental Filtering in Its Introduced Range.

Plants host diverse assemblages of fungi on their foliar tissues, both in internal compartments and on exterior surfaces. When plant distributions shift, they can move with their fungal associates (i.e., co-introduction) or acquire new associates present in the novel environment (host-jumping). The fungal communities that plants acquire influence a plant's ability to establish and spread in this new environment. Here, we aimed to assess whether invasive C. ciliaris hosts similar groups of fungi in its native and introduced ranges and to evaluate community overlap of fungi associated with foliar tissue of C. ciliaris and native and non-native plants within the introduced range. In the introduced range, the majority of OTUs associated with C. ciliaris were not found in its native range, although 3.2% of OTUs were common to both ranges. Of these shared OTU, 77.6% were found on co-occurring natives and non-natives in the introduced range, whereas 22.4% were unique to C. ciliaris indicating a possible co-introduction. Fungal communities within the introduced range contained a higher proportion of generalist symbionts and increased heterogeneity of foliar communities than in its native range. Within the introduced range, host phylogenetic distance explained more variation than native status. Our findings provide evidence that non-natives acquire fungi opportunistically from their environment, although host and environmental filtering is present suggesting that successful invasive plants may be able to limit the effect of poor symbionts and select for better ones. Future experimental work will be needed to confirm the occurrence of host selection and identify its mechanisms.

Palynology, micropalaeontology and geochemistry of the Eocene Rusayl Formation of Northern Oman

New palaeontological and geochemical data are presented for the Rusayl Formation of Northern Oman. Eocene palynomorphs (97 taxa) including many new to the Arabian Peninsula and a distinctive new ostracod assemblage (21 species including 11 new taxa) are described and key taxa illustrated. This represents the most diverse palynomorph assemblage yet recorded from the Eocene within the Arabian Peninsula area. 'Ostracods of this age are poorly known from the Middle East with only one species from this area found in the Oman material and a further three from western Pakistan. The palynology indicates a dominantly restricted shallow marine palaeoenvironment with distinct periods of strong marine influence during which dinocyst abundances increase markedly. The palynofloras are dominated by Nypa palm pollen typical of mangroves ( Spinizonocolpites and Proxapertites ). The palynofacies are dominated by cuticle and membrane material (leaf debris) and brown pseudoamorphous wood, indicating a marginal marine palaeoenvironment. The associated ostracod and foraminiferal assemblages broadly support these interpretations indicating a lagoonal to infra-littoral environment of deposition. Nannofossils are recorded for the first time from the formation and support a Middle Eocene age for the upper part of the Rusayl Formation. Inorganic geochemistry indicates that the fine-grained siliciclastic intervals were largely derived from ophiolitic material and pre-Permian basement. Shales and coals contain common oil-prone lipid rich cuticle and locally abundant gas-prone woody kerogen with pyrolysis S2 yields of up to 15.13 mg/g. Although thermally immature the sequence is sufficiently buried by a sediment overburden exceeding 5 km in the offshore to generate hydrocarbons.

The Working of Hard Animal Tissues in Eastern and Central Europe During the Last Glacial Maximum—Current Knowledge and Perspectives

The climatically unfavourable period of the Last Glacial Maximum (LGM; ca. 26–19 ka cal bp) is held responsible for a severe demographic crisis of hunter–gatherer populations, their retreat to a few refugial areas, the disruption of wide-ranging networks, and a considerable loss of cultural complexity in Eastern and Central Europe. The latitudes above 50°N appear to have been completely depopulated. Recent research has demonstrated a continuous occupation of the Carpathian Basin and the East Carpathian region during the LGM on one hand, and an ephemeral human presence in the Middle Danube, the Middle Rhine, and the Swiss Plateau on the other. The western part of the East European Plain, in particular the East Carpathians, is known for several large, Early Epigravettian open-air sites with well-preserved artefacts of antler, bone, and mammoth ivory. For Central Europe, the assemblage from Kammern-Grubgraben in Lower Austria is of pivotal importance. As osseous industries have shown to be an essential component of Upper Palaeolithic material culture, it is the aim of this contribution to provide an overview of the current state of knowledge on the processing of hard animal tissues in Eastern and Central Europe during the LGM. Starting out with a reevaluation of one of the largest and most diverse assemblages from the site of Cosăuţi in the Republic of Moldova (ca. 23–19 ka cal bp), contemporary assemblages from the area between the Bug River in the east and the Rhine in the west are presented, discussed and compared with the situation in Western Europe. Based on that, it can be asked what information osseous industries can provide about the development of technological traditions and dissemination of concepts during the LGM from a local and supraregional perspective.

New spider crabs (Brachyura, Majoidea) from the early Eocene of Spain with a reassignment of the species “Periacanthus” tetracornis

Spider crabs (superfamily Majoidea Samouelle, 1819) represent a highly diverse group within Eubrachyura de Saint Laurent, 1980. This study re-examines the species “Periacanthus” tetracornis Ferratges, Ortega Fernández, Moreno and Maza, 2014 (Roda Formation, lower Eocene of Spain) which was previously consider as a member of Epialtidae MacLeay, 1838 and it is included as a new genus of majoid crabs, Eoactinotocarcinu n. gen. Additionally, Tumulosternum ortegai n. sp. is described from the same geological unit expanding the distribution of this genus to the southern Pyrenees. These taxa were found in siliciclastic facies co-occurring with a diverse assemblage of decapod crustaceans and other invertebrates. These facies are interpreted as deposited in a prodelta environment supporting the idea of such environments as highly diversified areas of decapods during the Eocene. These new taxa represent the earliest known record of the Subfamily Actinotocarcininae Jenkins, 1974 and the genus Tumulosternum respectively.