International initiatives aimed at generating genomic resources, and particularly reference genomes, have flourished in recent years. Some focus on specific taxa, such as the Vertebrate Genomes Project, Bird Genome 10K Project, Bat1K Project, Global Invertebrate Genomics Alliance, 10 000 Plant Genomes Project, and 1000 Fungal Genomes project. Others focus on geographic regions, such as the California Conservation Genomics Project, Darwin Tree of Life for Britain and Ireland, Catalan Initiative for the Earth BioGenome Project in the Catalan territories, Endemixit in Italy, Norwegian Earth Biogenome Project, and SciLifeLab in Sweden, on applications such as the LOEWE Translational Biodiversity Genomics in Germany, or on ecological systems such as the Aquatic Symbiosis Genomics project. Collectively part of the Earth BioGenome Project (EBP), in Europe these initiatives are organized under the umbrella of the European Reference Genome Atlas (ERGA). A genome atlas of European biodiversityERGA is a pan-European scientific response to the current threats to biodiversity. Approximately one fifth of the ~200 000 eukaryotic species present in Europe can be inferred to be at risk of extinction according to the International Union for Conservation of Nature (IUCN) Red List classification (this estimate only considers the assessed species; https://www.iucn.org/regions/europe/our-work/biodiversity-conservation/european-red-list-threatened-species).ERGA aims to generate reference genomes of European eukaryotic species across the tree of life, including threatened, endemic, and keystone species, as well as pests and species important to agriculture, fisheries, and ecosystem function and stability. ERGA builds upon current genomic consortia in EU member states, EU Associated Countries, representatives of other countries within the European bioregion, and international collaborators. These reference genomes will address fundamental and applied questions in conservation, biology, and health. ERGA seeks to alert the EU about the potential of conservation genomics, and particularly the role of reference genomes, in biodiversity assessment, conservation strategies, and restoration efforts.

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Aim Our aim was to assess the evolutionary history of the land snail genus Xerocrassa on the Balearic Islands with a molecular phylogeny. We investigated how the main palaeogeographical events and climate changes which occurred in the Western Mediterranean basin influenced the current diversity and distribution of the genus within the archipelago.Location The Balearic Islands, Western Mediterranean.Methods A dataset of 2540-bp DNA sequences was generated from one nuclear and two mitochondrial gene fragments obtained from 170 specimens representing 112 populations. Applying maximum likelihood and Bayesian phylogenetic methods and a Bayesian molecular clock, we examined the evolutionary history of the genus Xerocrassa. We also used genetic-based species delimitation models to clarify the taxonomy of the genus in the archipelago. ResultsWe provide the first molecular phylogeny of the endemic Xerocrassa of the Balearic Islands. The monophyly of several currently recognized species was not supported. The genus colonized the archipelago in a single event during the Messinian salinity crisis (5.96-5.33 Ma) from the eastern part of the Iberian Peninsula. The hypothesis of a relatively recent origin for the evolutionary diversification within the group was supported by molecular clock analyses. Allopatric speciation occurred after the isolation of the Pityusic and Gymnesic island systems. Moreover, most of the extant species are the result of within-island speciation events.Main conclusions Historical biogeographical reconstruction strongly supports the hypothesis of Messinian salinity crisis as the colonization period of the Balearic Islands for Xerocrassa. Major climate changes experienced in the Western Mediterranean basin during the Plio-Pleistocene influenced the withinisland speciation processes postulated for Xerocrassa. The high morphological diversity in the genus represents 11 species and a strong phylogeographical structure within the main islands.

Aim We infer the evolutionary history of the land snail genus Allognathus from a molecular phylogeny. An approximate temporal framework for its colonization of the Balearic Islands and diversification within the archipelago is provided according to palaeogeographical events in the western Mediterranean Basin.Location The Balearic Islands, Western Mediterranean.Methods A 2461-bp DNA sequence dataset was generated from one nuclear and two mitochondrial gene fragments in 87 specimens, covering all nominal taxa of the genus Allognathus. Through maximum-likelihood and Bayesian phylogenetic methods along with a Bayesian molecular clock, we examined the evolutionary history of the group. Ancestral distribution ranges were estimated for divergence events across the tree using a Bayesian approach. We also used genetic species-delimitation models to determine the taxonomy of Allognathus.Results We provided the first molecular phylogeny of Allognathus, a genus endemic to the Balearic Islands. The origin of the genus in the Balearic Islands was dated to the middle Miocene based on palaeogeographical events in the Western Mediterranean. During the late Miocene and Pliocene, several diversification events occurred within the archipelago. The ancestral range of Allognathus was reconstructed as the north-eastern Tramuntana Mountains of Mallorca.Main conclusions Three species were delimited within the genus, one of which has at least five subspecies. The phylogenetic reconstruction showed a high degree of parallelism between the divergence of the main Allognathus lineages and the palaeogeography of the Balearic Islands. The genus appears to have colonized Mallorca from the south-east of the Iberian Peninsula during the middle Miocene. Sea level fluctuations that took place in the Western Mediterranean from the Messinian to the present are consistent with the diversification and secondary contacts of the phylogroups of Allognathus, as well as their distribution ranges. The middle Miocene could have been a period for the colonization of the Balearic Islands by other terrestrial organisms.

In terrestrial snails, thermal selection acts on shell coloration. However, the biological relevance of small differences in the intensity of shell pigmentation and the associated thermodynamic, physiological, and evolutionary consequences for snail diversity within the course of environmental warming are still insufficiently understood. To relate temperature‐driven internal heating, protein and membrane integrity impairment, escape behavior, place of residence selection, water loss, and mortality, we used experimentally warmed open‐top chambers and field observations with a total of >11,000 naturally or experimentally colored individuals of the highly polymorphic species Theba pisana (O.F. MÜLLER, 1774). We show that solar radiation in their natural Mediterranean habitat in Southern France poses intensifying thermal stress on increasingly pigmented snails that cannot be compensated for by behavioral responses. Individuals of all morphs acted neither jointly nor actively competed in climbing behavior, but acted similarly regardless of neighbor pigmentation intensity. Consequently, dark morphs progressively suffered from high internal temperatures, oxidative stress, and a breakdown of the chaperone system. Concomitant with increasing water loss, mortality increased with more intense pigmentation under simulated global warming conditions. In parallel with an increase in mean ambient temperature of 1.34°C over the past 30 years, the mortality rate of pigmented individuals in the field is, currently, about 50% higher than that of white morphs. A further increase of 1.12°C, as experimentally simulated in our study, would elevate this rate by another 26%. For 34 T. pisana populations from locations that are up to 2.7°C warmer than our experimental site, we show that both the frequency of pigmented morphs and overall pigmentation intensity decrease with an increase in average summer temperatures. We therefore predict a continuing strong decline in the frequency of pigmented morphs and a decrease in overall pigmentation intensity with ongoing global change in areas with strong solar radiation.