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Infaunal organisms living within marine sediments can provide valuable information about the effect of key environmental factors, acting as ecological indicators e.g. species composition and diversity, tolerance to pollution, or resilience degree facing abiotic stressors such as wave storm events. These organisms may modify their environment through burrowing behavior, enhancing mixing, and nutrient and oxygen cycling, which are crucial for ecosystem health. Simultaneously, such high-energy events (wave storms) may impair the ecophysiology of organisms, altering trophic interactions in this particular food web. A set of behavioral, ecophysiological, and stress/immune responses were monitored for the infaunal clam Polititapes rhomboides exposed to key abiotic stressors identified in our coasts (Rías Baixas, NW Iberian Peninsula) as drivers of massive mortality events in the past: sediment mobilization disturbance (SM) in the bottom seafloor, and seawater warming (SW). Valve opening was clearly reduced during physical disturbance while minor effects were observed for temperature increase (+3 °C, from 15 °C to 18 °C). Nevertheless, a highly resilient behavior was noted for the shell opening of clams (crucial for vital physiological functions) after each physical disturbance cycle, with similar profiles to organisms kept under control calm scenarios. The physiology of clams was also altered by sediment mobilization, resulting in a decline of clearance rates (feeding activity) but only with regard to short-term periods after disturbance (e.g. hours). In contrast, temperature increase caused clearance rates to also increase significantly, linked to the optimal diet supplemented during the experiment. The combination of both stressors (sediment mobilization and temperature increase simultaneously) resulted in elevated oxygen consumption rates and nitric oxide production by the clams as activated responses to stress. Again, the ability of the clams to recover from physical

Animal welfare is an issue of growing public concern, and of great importance for the incipient development of octopus aquaculture. The common octopus, Octopus vulgaris, is a species of great commercial interest, and an excellent candidate for aquaculture diversification. Overexploitation of natural stocks and high market demand mean that sustainable octopus farming has a positive impact on natural stocks, thus being a tool to alleviate fishing pressure and preserve the species. Once the zootechnical deficiencies have been overcome, the optimization and standardisation of specific approaches and practices to monitor and safeguard animal welfare are needed to achieve a sustainable culture. Criteria for assessing welfare should focus primarily on diet, appropriate housing conditions and living environment as well as behaviour and health. In this study, specific octopus welfare markers defined as biological Operational Welfare Indicators (OWIs) have been identified in order to be measured and integrated into good aquaculture practices monitoring plans. Here is presented the first determination of biological OWI for pathogen identification, disease diagnosis and animal health monitoring in captivity. Non invasive diagnostic tools for pathology prevention and control includes microbiological analysis of tank water and skin, and parasitological analysis of fecal smears. Quantitative PCR protocols have been optimized for early identification and absolute quantification of pathogens such as Vibrio sp. in mucus and tank water, or Aggegata octopiana in fecal samples. In addition, specific parameters involved in defense mechanisms, such as antibacterial or antiviral antivities of skin mucus have been studied as indicators of natural defense capability. The results presented on the identification and selection of biological OWIs will be a key tool for the incipient development of octopus aquaculture

The lack of cell cultures in mollusks in general and the common octopus, in particular, is a major problem when carrying out in vitro assays that help to deepen the knowledge of the main immune cells of this species with interest for aquaculture. Cryopreservation becomes an alternative to this process that allows for maintaining viable and functional cells after freezing/thawing processes [1]. Keeping cells in a viable functional state for long periods will allow to cover a larger repertoire of studies with the same sample or to perform time courses, avoiding logisticbottlenecks that could arise due to the loss of viability and/or functionality of the cells on the lab bench, the lack of time to develop all the desired assays in the same day or the possible losses derived from transporting the samples between different laboratories [2]. Additionally, high-quality suspensions of viable and functional cells are required for successful massive sequencing studies, such as single-cell analysis, where these aspects are the key to optimal identification. Here we present the first cryopreservation study of octopus hemocytes. The cells maintained their responsiveness to zymosan after two months of freezing, producing oxygen radicals, and were able to phagocyte similarly to fresh cells. Viability was maintained at levels around 80% after four months at -80ºC, and high levels of RNA integrity were obtained, suggesting that the optimized freeze-thaw process is suitable for using the cells in functional and molecular studies. The results presented here will facilitate the study of the functions of the most important immune cells in this species of enormous interest for aquaculture diversification

The common octopus (Octopus vulgaris) is one of the most economically important marine species in the world, highly valued as food source for its high protein content. This cephalopod is subject to active extractive fishing and has recently been cultured in experimental systems. Many of the body parts of fishery and aquaculture species are removed before reaching the consumer in order to improve preservation, reduce shipping weight and increase the quality of the final product. However, the generation of these by- products can be a valuable source of bioactive compounds. Particularly, the skin mucus from common octopus has shown antimicrobial and antioxidant properties, among others, playing a crucial role in the animal defense mechanism acting as first barrier against a wide variety of chemical, physical and biological stressors. Previous proteomic studies have allowed the identification of potential bioactive peptides in the skin mucus and ink of the common octopus. Based on their possible interest from an immune point of view, three mucus peptides (from parent proteins hemocyanin, complement factor and tintin) were selected and biosynthesized to determine their functional activity. For this purpose, in vitro assays were performed to analyze their putative antibacterial and antitumoral activities, as well as to study their ability to induce chemotaxis. In addition, and with the aim to determine whether other different bioactive compounds present in octopus skin mucus extracts from intravenously immunostimulated animals have similar activity, this functional analysis was also performed in skin mucus from octopus immunostimulated with different intravenous stimulus

Seven Fusarium species complexes are treated, namely F. aywerte species complex (FASC) (two species), F. buharicum species complex (FBSC) (five species), F. burgessii species complex (FBURSC) (three species), F. camptoceras species complex (FCAMSC) (three species), F. chlamydosporum species complex (FCSC) (eight species), F. citricola species complex (FCCSC) (five species) and the F. concolor species complex (FCOSC) (four species). New species include Fusicolla elongata from soil (Zimbabwe), and Neocosmospora geoasparagicola from soil associated with Asparagus officinalis (Netherlands). New combinations include Neocosmospora akasia, N. awan, N. drepaniformis, N. duplosperma, N. geoasparagicola, N. mekan, N. papillata, N. variasi and N. warna. Newly validated taxa include Longinectria gen. nov., L. lagenoides, L. verticilliforme, Fusicolla gigas and Fusicolla guangxiensis. Furthermore, Fusarium rosicola is reduced to synonymy under N. brevis. Finally, the genome assemblies of Fusarium secorum (CBS 175.32), Microcera coccophila (CBS 310.34), Rectifusarium robinianum (CBS 430.91), Rugonectria rugulosa (CBS 126565), and Thelonectria blattea (CBS 952.68) are also announced here

High-energy hydrodynamic events associated to currents and waves may disturb bivalve mollusks´ ecophysiology, especially those buried in the the sea bed due to sediment mobilization. Evidences of massive mortality for the clam Polititapes rhomboides (banded carpet shell clam) in Galicia (NW Spain) have been associated to warm water temperatures and high wave magnitudes above climatic averages and the presence of rickettsias (intracellular prokaryotic colonies) in gills (Villalba et al. 1999; Darriba et al. 2019; Villacieros-Robineau et al. 2021)

High-energy hydrodynamic events associated with currents and waves may disturb bivalve mollusks' ecophysiology, especially those buried in the sea bed where the bottom boundary layer dynamics may mobilize and resuspend the surface sediments. Evidence of massive mortality for the clam Polititapes rhomboides (banded carpet shell clam) in 2010 in Galicia (NW Spain) has been associated to warm water temperatures and high wave magnitudes above climatic averages and the presence of rickettsias (intracellular prokaryotic colonies) in gills. To monitor in the laboratory the environmental conditions observed in 2010, clams were subjected to intense sediment mobilization (four cycles of sediment remobilization, each followed by a calm period) and seawater warming (from 15°C to 18°C). Immune system, behavioral, and ecophysiological clams' responses were then evaluated. Nitric oxide (NO) production increased synergistically with seawater warming and sediment remobilization. Taking into account the four cycles of sediment remobilization, clams responded by increasing NO production as early as the first cycle in what we could call an acute effect. However, the most striking effect was the increased NO response after a second stimulation (the following sediment remobilization cycles), suggesting that clams achieve a kind of alertness the first time they are exposed to a stimulus through a mechanism possibly related to "trained immunity". Seawater warming and sediment mobilization presented also synergistic effects causing the lowest valve opening amplitude. Besides, sediment remobilization caused abrupt decrease in clearance rates of clams suggesting that reduced valve opening during this stage may have altered filtration processes of phytoplankton uptake. Metabolic rate as oxygen consumption showed a synergistic increase with both abiotic stressors. Considering the NO response and the ecophysiology data we could suggest that clams respond to stress increasing metabolism to obtain

[EN] The common octopus, Octopus vulgaris, is a species with a high potential for aquaculture diversification. Recently, for the first time, it has been possible to obtain specimens up to the pre-settlement stage, with high levels of growth and survival, allowing the investigation of different biological processes. DNA methylation is an epigenetic process capable of controlling gene transcription, facilitating differential expression depending on environmental conditions. In the present work, RRBS sequencing and comparative study of the methylome of O. vulgaris paralarvae at different stages of development and subjected to different diet and temperature conditions has been carried out in order to assess how environmental conditions can vary the methylation profile of these organisms in culture conditions. The results obtained after the comparative analyses show the necessity of demethylation for the progress of their correct development. In addition, certain environmental conditions, such as low temperature or optimal diet, seem to facilitate demethylation. The transcriptional silencing or activation by methylation, together with increased annotation of the genes involved, will allow the identification of marker genes. The results of the present work will help to better understand the requirements for optimal development of this species, contributing to improve the transfer of the culture to industrial scale, [ES] El pulpo común, Octopus vulgaris, es una especie con un elevado potencial para la diversificación de la acuicultura. Recientemente se han obtenido por primera vez ejemplares hasta la fase de pre-asentamiento, con altos niveles de crecimiento y supervivencia, permitiendo investigar distintos procesos biológicos. La metilación del ADN es un proceso epigenético capaz de controlar la transcripción de los genes, facilitando una expresión diferencial en función de las condiciones del medio. En el presente trabajo se ha llevado a cabo la secuenciación por el método RRBS y estudio comparado del metiloma de paralarvas de O. vulgaris en diferentes estadios de desarrollo y sometidas a diferentes condiciones de dieta y temperatura con objeto de valorar cómo las condiciones ambientales pueden hacer variar su perfil de metilación en el cultivo. Los resultados obtenidos muestranla necesidad de la desmetilación para el avance de su correcto desarrollo. Además, determinadas condiciones ambientales, como la baja temperatura o una dieta óptima parecen facilitar dicha desmetilación. El silenciamiento o activación transcripcional mediante metilación, junto con el incremento de la anotación de los genes implicados, permitirán la identificación de genes marcadores. Los resultados obtenidos ayudarán a comprender mejor los requerimientos para un desarrollo óptimo de esta especie, contribuyendo a mejorar la transferencia del cultivo a escala industrial

Dating meteoritic materials by the Pb–Pb isochron method depends on constructing linear arrays typically defined by mixtures of initial and radiogenic Pb after the removal of terrestrial contaminant Pb. The method also depends on minimizing the amount of laboratory Pb blank added to the sample during processing and analyses. With the aim to analyze smaller sample sizes and decrease processing times, we have devised a new method for the construction of isochrons using the stepwise dissolution of meteoritic materials that better defines reduced amounts of Pb blank, reduces the risk of random anomalous Pb contamination, and increases sample throughput. Samples are processed in a PFA Teflon™ pipette tip fitted with a frit inside a heated, sealed chamber that can be manually over-pressured to expel reagents directly into a PFA Teflon™ vial below. With four independent chambers, three samples can be processed simultaneously with a fourth position to assess the Pb contribution of the combined blank and spike for each step. The matched blank-spike Pb for each step provides a specific blank estimate for each step that ensures a more accurate correction for non-sample Pb and, therefore, reduces the uncertainty on each analysis. We assess the performance of this new method by reporting the results of dating a fragment of a chondrule from the well-characterized CBa chondrite Gujba and compare these results with previously published data for this meteorite. The improvements reduce the minimum sample sizes that can be successfully dated by the Pb–Pb method, an important development for size-limited materials such as small chondrules and samples returned from space missions.