The reference genome of Lewinskya acuminata (H. Philib.) F. Lara, Garilleti & Goffinet will enable phylogenomic, biogeographic, and evolutionary studies within the Orthotrichaceae and related bryophyte lineages at a depth previously inaccessible. This species of moss is among the most representative of the Mediterranean epiphytic communities and can be readily identified by its long-acuminate leaves, fusiform capsules with a vestigial exostome, a well-developed endostome of six broad segments, and a dark, puckered peristome mouth when dry. The entirety of the genome sequence was assembled into 6 contiguous chromosomal pseudomolecules, while the mitochondrial and chloroplastic genomes were assembled, respectively, as a single contig of 104,820 bp and two contigs of 123,029 bp and 122,994 bp. This chromosome-level assembly encompasses 0.25 Gb, composed of 51 contigs and 13 scaffolds, with contig and scaffold N50 values of 11.5 Mb and 40.8 Mb, respectively.

Marine ecosystems are hotspots of biodiversity and biogeochemical activity, yet much of their complexity remains largely inaccessible without genome-resolved data. Here we present a curated dataset of 52 eukaryotic metagenome-assembled genomes (MAGs) reconstructed from samples collected between April 2019 and January 2020 at three NEREA (Naples Ecological REsearch for Augmented observatories) sites in the Gulf of Naples. NEREA is a coastal observatory integrating physical, chemical and biological measurements with state-of-the-art metagenomics. The eukaryotic MAGs have an average completeness of ~55% and genome size of ~20 Mb. Predicted proteins were functionally annotated against UniProtKB, InterPro, and eggNOG databases, and each MAG was taxonomically classified using a curated RNA polymerase A reference dataset. The recovered MAGs encompass diverse eukaryotic lineages, primarily Ochrophyta, Chlorophyta and Haptophyta. Building on the Tara Oceans eukaryotic MAG legacy, this release represents the first reconstruction of eukaryotic MAGs from a coastal time series, enabling temporal and functional analyses of eukaryotic plankton.

ABSTRACT Parasitism is one of the most widespread trophic strategies in nature, though its diversity and ecological distribution in marine ecosystems remain poorly characterized. Apicomplexa are a major clade of obligate parasites best known for medically important taxa, yet their diversity and distribution in the ocean is still largely unresolved. Here, we used metabarcoding data from the Tara expeditions to investigate the diversity, distribution, and environmental drivers of Apicomplexa across coral reef ecosystems and adjacent oceanic habitats. By integrating samples spanning planktonic communities, coral tissues, and marine sediments across multiple oceanic regions, we substantially expand the known phylogenetic breadth of marine apicomplexans. Although apicomplexans were generally low in relative abundance, they were widely distributed across marine environments. Community composition differed markedly among habitats. Corallicolid lineages were consistently associated with coral hosts, whereas planktonic samples harbored a greater diversity of apicomplexans, dominated by crustacean-associated gregarines. Sediments contained particularly high apicomplexan richness, including several poorly characterized groups. Capitalizing on the pan-Pacific transect of the expedition, we resolved biogeographic patterns in apicomplexan diversity across ocean basins: tropical regions showed the highest overall diversity, while polar environments contained distinct apicomplexan assemblages not detected in other ocean biomes. Together, these results highlight the extensive and previously underappreciated diversity of marine Apicomplexa and demonstrate that integrating multiple marine biomes is essential for resolving the phylogenetic and ecological breadth of parasitism in the ocean.

The Eunicella cavolini reference genome provides an important resource to study the adaptation of this species to different environments and anthropic pressures. This species is impacted by human activities, including climate change, and this reference genome will be useful to study the genomic evolution of this species. The entirety of the genome sequence was assembled into 17 contiguous chromosomal pseudomolecules. This chromosome-level assembly encompasses 0.49 Gb, composed of 159 contigs and 46 scaffolds, with contig and scaffold N50 values of 7.7 Mb and 51.1 Mb, respectively.

Bacteria and mobile genetic elements (MGEs) have coevolved for billions of years in an enduring evolutionary arms race, leading to the emergence and diversification of a vast arsenal of defense and counter-defense systems. In the last recent years, high-throughput screening methods and genome-resolved metagenomics have markedly enhanced our understanding of the diversity and abundance of immune systems across cultured and uncultured microorganisms. This fueled subsequent interest in better understanding the dynamic tri-kingdom interplay between bacteria, bacteriophages, and eukaryotic cells, and led to renewed efforts to improve alternative antibacterial phage-based therapies. Here, we discuss the evolutionary and ecological dynamics underlying the bacteria-MGE arms race, recent findings on bacterial defensomes, MGE counter-defensomes, holodefensomes, and their key role in the development of microbiome-targeted therapies. To this end, we argue why and how highly conserved anti-MGE defense systems should be prioritized as promising targets for the development of next-generation bacterial inhibitors with broad biomedical relevance, supported by a comprehensive analysis of their distribution and diversity across bacteria.

The Diadema setosum reference genome is important for understanding the species adaptation to the Mediterranean marine environment, where it has been newly introduced. The species is a Lessepsian migrant, gradually expanding to the eastern Mediterranean basin, driven by rising water temperature. Diadema setosum often dominates over native sea urchin species or coexists with them in rocky habitats. Sea urchins are environment-forming species, as they are intensive grazers responsible for habitat degradation and bottom erosion. A high-quality reference genome could provide valuable insights into the adaptive ability of D. setosum populations, supporting better monitoring and conservation efforts. Additionally, the genome will also contribute towards having a record of recently introduced populations to the Mediterranean, allowing researchers to track their evolution over time. A total of 22 contiguous chromosomal pseudomolecules were assembled from the genome sequence. This chromosome-level assembly encompasses 0.91 Gb, composed of 745 contigs and 101 scaffolds, with contig and scaffold N50 values of 2.2 Mb and 39.8 Mb, respectively.

Hanak's bat ( Pipistrellus hanaki Hulva and Benda 2004) is one of the most range restricted mammals in Europe, since it occurs only in Cyrenaica, Libya, and Crete (Greece). It is currently classified as 'Vulnerable' on the IUCN Red List, with its foraging habitat threatened by a number of human activities. The reference genome of Hanak's bat ( Pipistrellus hanaki ) will provide a crucial resource for uncovering the species phylogenetic history and will help assess the degree of genetic isolation among its populations. A total of 23 contiguous chromosomal pseudomolecules (sex chromosomes included) were assembled from the genome sequence. This chromosome-level assembly encompasses 1.9 Gb, composed of 447 contigs and 141 scaffolds, with contig and scaffold N50 values of 48.7 Mb and 89.1 Mb, respectively.

Abstract The human gut microbiome exhibits reproducible configurations, yet the ecological forces connecting them to health remain unclear. Here, using enterosignature-based stratification of 5,170 individuals from the Le French Gut cohort, we identified hydrogen disposal as a key determinant of population-scale microbiome configurations, independently replicated in a meta-cohort (n = 5,107). Microbial configurations followed a continuum of hydrogen recycling capacity and redox-associated functions, aligned with dietary patterns and health indicators. Methanogenesis-dominant partitions were associated with more favorable health profiles, whereas acetogenesis-enriched partitions exhibited features of low-grade inflammation, and increased digestive symptoms, perceived stress and antidepressant use. Experimental characterization of mucin profiles highlighted differences across partitions and alterations in Bacteroides -enriched configurations. Together, our findings support an ecological host-microbiome framework linking hydrogen metabolism, redox ecology, and host health, offering microbiome-informed targets for precision intervention. Graphical abstract

ABSTRACT Coral reefs are among the most diverse ecosystems on Earth, yet the diversity and structure of their associated microeukaryotic communities remain poorly resolved. We characterized reef-associated eukaryomes across 113 reefs spanning the Pacific Ocean using more than 6,300 samples from corals, seawater, and sediments during the Tara Pacific expedition. We identified ∼121,000 eukaryotic ASVs, revealing one of Earth’s largest undocumented reservoirs of eukaryotic diversity; over 80% of the recovered diversity was previously undetected in global ocean surveys and fewer than 2% of sequences matched reference databases. Reef habitats supported highly distinct communities, with sediments and seawater harboring 20–40-fold higher richness than corals. Unexpectedly, coral-associated communities across 29 host lineages were consistently dominated by small metazoans, particularly demosponges and maxillopods, identifying these taxa as pervasive and previously unrecognized components of coral eukaryomes alongside Apicomplexa. Across the Pacific, eukaryome composition was strongly structured by environmental gradients, with thermal stress emerging as the primary driver of community turnover. Together, these results identify coral reefs as a globally important reservoir of hidden eukaryotic diversity and reveal the reef eukaryome as a sensitive indicator of ecosystem reorganization under climate change.

The Biodiversity Genomics Europe (BGE) Project has the overarching aim of accelerating the use of genomic science to enhance understanding of biodiversity, monitor biodiversity change, and guide interventions to address its decline. The BGE Project comprises activities focused on DNA Barcoding (Barcoding Stream) and Reference Genome Generation (Genomes Stream) for eukaryotic species across Europe, bringing together two European networks: the International Barcode of Life in Europe (iBOL Europe) and the European Reference Genome Atlas (ERGA). This publication is an abridged version of the successful grant proposal developed jointly by iBOL Europe and ERGA in response to the Horizon Europe call HORIZON-CL6-2021-BIODIV-01-01. Two key strands of genomic science form the basis of this proposal: DNA barcoding - sequencing short, standardised genomic regions to tell the world’s species apart, transforming the speed of completion of the inventory of life on Earth and providing the foundations of a global bio-surveillance system for biodiversity; and genome sequencing - generating high-quality complete reference genomes for all species on Earth, transforming understanding of biodiversity at the genetic level, and delivering fundamental knowledge of how biological systems function and how species respond and adapt to environmental change. The BGE Project objectives are focused on (i) Capacity: To establish functioning biodiversity genomics networks at the European level to connect and grow community capacity to use genomic tools to tackle the biodiversity crisis; (ii) Production: To establish and implement large-scale biodiversity genomic data generation pipelines for Europe to accelerate the production and accessibility of genomic data for biodiversity characterisation, conservation, and biomonitoring; and (iii) Application: To apply genomic tools to enhance understanding of pan-European biodiversity and biodiversity declines to improve the efficacy of management interventions and biomonitoring programmes.

Holothuria sanctori is a common species of sea cucumber found in the Mediterranean Sea and the Northeast Atlantic Ocean. It typically inhabits shallow rocky and sandy seabeds, where it plays a key ecological role as a sediment engineer processing organic matter ts and thereby contributing to nutrient cycling. As an edible species, H. sanctori is harvested in several countries. Although it is currently listed as a species of "Least Concern" on the IUCN Red List, the absence of a regulatory framework to prevent overexploitation poses a risk of population decline. Given its ecological significance and economic value, H. sanctori has become a focal point in both marine conservation and aquaculture research. The entirety of the genome sequence was assembled into 23 contiguous chromosomal pseudomolecules. This chromosome-level assembly encompasses 1.2 Gb, composed of 135 contigs and 46 scaffolds, with contig and scaffold N50 values of 19.9 Mb and 50.7 Mb, respectively.

Dailognatha quadricollis (Coleoptera: Tenebrionidae) is a darkling beetle native to the Balkans and Eastern Mediterranean, with a range extending from Croatia to Lebanon. It is a morphologically diverse species, comprising numerous subspecies, particularly concentrated in the Aegean region. The reference genome of Dailognatha quadricollis will enable phylogenetic, population and evolutionary research. The entirety of the genome sequence was assembled into 11 contiguous chromosomal pseudomolecules and the X sex chromosome. This chromosome-level assembly encompasses 0.52 Gb, composed of 393 contigs and 322 scaffolds, with contig and scaffold N50 values of 4.3 Mb and 23.6 Mb, respectively.

The European Marine Omics Biodiversity Observation Network (EMO BON) is a long-term genomic observatory run by the European Research Infrastructure European Marine Biological Resource Centre (EMBRC). It was established in 2021 to support the challenges of biodiversity observation and unsystematic management of biodiversity data in the European seas. EMO BON introduced and coordinated the systematic and harmonised observation of biodiversity amongst more than fourteen marine stations in the European coastline. Here, we report the next release (Release 2) of shotgun metagenomic data from seawater and sediment microbial communities.

Dendarus foraminosus Mulsant and Rey, 1855 is a darkling beetle in the family Tenebrionidae and one of the many Dendarus species endemic to the island of Crete. Dendarus foraminosus is a commonly found species and is widespread in the lowland and montane phrygana and maquis of central Crete. The species is classified as Least Concern (LC) by the IUCN Red List. The reference genome of Dendarus foraminosus will enable phylogenetic, population, and evolutionary research regarding this endemic species and its close relatives. A total of 11 contiguous chromosomal pseudomolecules (sex chromosomes included) were assembled from the genome sequence. This chromosome-level assembly encompasses 0.59 Gb, composed of 430 contigs and 415 scaffolds, with contig and scaffold N50 values of 24.4 Mb and 51.9 Mb, respectively.

Holothuria sanctori is a common species of sea cucumber found in the Mediterranean Sea and the Northeast Atlantic Ocean. It typically inhabits shallow rocky and sandy seabeds, where it plays a key ecological role as a sediment engineer processing organic matter ts and thereby contributing to nutrient cycling. As an edible species, H. sanctori is harvested in several countries. Although it is currently listed as a species of "Least Concern" on the IUCN Red List, the absence of a regulatory framework to prevent overexploitation poses a risk of population decline. Given its ecological significance and economic value , H. sanctori has become a focal point in both marine conservation and aquaculture research. The entirety of the genome sequence was assembled into 23 contiguous chromosomal pseudomolecules. This chromosome-level assembly encompasses 1.2 Gb, composed of 135 contigs and 46 scaffolds, with contig and scaffold N50 values of 19.9 Mb and 50.7 Mb, respectively.

Dendarus foraminosus Mulsant and Rey, 1855 is a darkling beetle in the family Tenebrionidae and one of the many Dendarus species endemic to the island of Crete. Dendarus foraminosus is a commonly found species and is widespread in the lowland and montane phrygana and maquis of central Crete. The species is classified as Least Concern (LC) by the IUCN Red List. The reference genome of Dendarus foraminosus will enable phylogenetic, population, and evolutionary research regarding this endemic species and its close relatives. A total of 11 contiguous chromosomal pseudomolecules (sex chromosomes included) were assembled from the genome sequence. This chromosome-level assembly encompasses 0.59 Gb, composed of 430 contigs and 415 scaffolds, with contig and scaffold N50 values of 24.4 Mb and 51.9 Mb, respectively.

The reference genome of Lewinskya acuminata (H. Philib.) F. Lara, Garilleti & Goffinet will enable phylogenomic, biogeographic, and evolutionary studies within the Orthotrichaceae and related bryophyte lineages at a depth previously inaccessible. This species of moss is among the most representative of the Mediterranean epiphytic communities and can be readily identified by its long-acuminate leaves, fusiform capsules with a vestigial exostome, a well-developed endostome of six broad segments, and a dark, puckered peristome mouth when dry. The entirety of the genome sequence was assembled into 6 contiguous chromosomal pseudomolecules, while the mitochondrial and chloroplastic genomes were assembled, respectively, as a single contig of 104,820 bp and two contigs of 123,029 bp and 122,994 bp. This chromosome-level assembly encompasses 0.25 Gb, composed of 51 contigs and 13 scaffolds, with contig and scaffold N50 values of 11.5 Mb and 40.8 Mb, respectively.

Environmental DNA (eDNA) metabarcoding emerged as a powerful method for biodiversity monitoring, offering non-invasive, reproducible, and scalable assessments. However, its implementation in marine environments and remote regions still presents significant technical and logistical challenges. Here, we tested several methodologies to propose a comprehensive field-adapted eDNA metabarcoding workflow, from sampling to taxonomic analysis, designed for the specific challenge of fish biodiversity monitoring in coral reefs, but transferable to various aquatic ecosystems. We use large-volume water sampling using a custom-built autonomous underwater filtration system, which reduces contamination risks, simplifies logistics, and enhances sampling consistency. In this frame, we assess the efficiency of our custom underwater filtration system, different filter porosities, and water volumes to optimize DNA yield, showing that 20 L filtered on a 1.2 μm pore-size filter was optimal for collecting fish eDNA. We chose the mitochondrial 12S rRNA for DNA amplification then Oxford Nanopore Technologies sequencing for its portability and compatibility with tropical fieldwork. We developed a high-resolution 12S reference database encompassing around 400 fish sequences, representing over 50% of the known fish biodiversity in French Polynesia. Finally, we benchmark eDNA-based biodiversity data against traditional visual census observations across multiple reef habitats and temporal replicates. Our approach enables high-resolution monitoring both at spatial and temporal scales while providing a more comprehensive assessment of fish biodiversity richness compared to visual census methods. Diel sampling revealed pronounced temporal structure, with nocturnal taxa enriched at night. This study validates a fully integrated eDNA metabarcoding workflow, from field collection to taxonomic analysis, in diverse and remote marine ecosystems, providing a scalable and cost-efficient framework solution for long-term biodiversity monitoring in remote regions.

Dailognatha quadricollis (Coleoptera: Tenebrionidae) is a darkling beetle native to the Balkans and Eastern Mediterranean, with a range extending from Croatia to Lebanon. It is a morphologically diverse species, comprising numerous subspecies, particularly concentrated in the Aegean region. The reference genome of Dailognatha quadricollis will enable phylogenetic, population and evolutionary research. The entirety of the genome sequence was assembled into 11 contiguous chromosomal pseudomolecules and the X sex chromosome. This chromosome-level assembly encompasses 0.52 Gb, composed of 393 contigs and 322 scaffolds, with contig and scaffold N50 values of 4.3 Mb and 23.6 Mb, respectively.

Holothuria sanctori is a common species of sea cucumber found in the Mediterranean Sea and the Northeast Atlantic Ocean. It typically inhabits shallow rocky and sandy seabeds, where it plays a key ecological role as a sediment engineer processing organic matter ts and thereby contributing to nutrient cycling. As an edible species, H. sanctori is harvested in several countries. Although it is currently listed as a species of "Least Concern" on the IUCN Red List, the absence of a regulatory framework to prevent overexploitation poses a risk of population decline. Given its ecological significance and economic value, H. sanctori has become a focal point in both marine conservation and aquaculture research. The entirety of the genome sequence was assembled into 23 contiguous chromosomal pseudomolecules. This chromosome-level assembly encompasses 1.2 Gb, composed of 135 contigs and 46 scaffolds, with contig and scaffold N50 values of 19.9 Mb and 50.7 Mb, respectively.