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The Antarctic shelf’s marine biodiversity has been greatly influenced by the climatic and glacial history of the region. Extreme temperature changes led to the extinction of some lineages, while others adapted and flourished. The amphipod genus Epimeria is an example of the latter, being particularly diverse in the Antarctic region. By reconstructing a time-calibrated phylogeny based on mitochondrial (COI) and nuclear (28S and H3) markers and including Epimeria species from all oceans, this study provides a temporal and geographical framework for the evolution of Antarctic Epimeria. The monophyly of this genus is not supported by Bayesian Inference, as Antarctic and non-Antarctic Epimeria form two distinct wellsupported clades, with Antarctic Epimeria being a sister clade to two stilipedid species. The monophyly of Antarctic Epimeria suggests that this clade evolved in isolation since its origin. While the precise timing of this origin remains unclear, it is inferred that the Antarctic lineage arose from a late Gondwanan ancestor and hence did not colonize the Antarctic region after the continent broke apart from the other fragments of Gondwanaland. The initial diversification of the clade occurred 38.04 Ma (95% HPD [48.46 Ma; 28.36 Ma]) in a cooling environment. Adaptation to cold waters, along with the extinction of cold-intolerant taxa and resulting ecological opportunities, likely led to the successful diversification of Epimeria on the Antarctic shelf. However, there was neither evidence of a rapid lineage diversification early in the clade’s history, nor of any shifts in diversification rates induced by glacial cycles. This suggests that a high turnover rate on the repeatedly scoured Antarctic shelf could have masked potential signals of diversification bursts.

Eleven species of Glessulinae belonging to the genera Glessula Martens, 1860 (three species) and Rishetia Godwin-Austen, 1920 (eight species) are reported from Nepal, six of which are new to science and are described here, viz., G. tamakoshi Budha & Backeljau, sp. n., R. kathmandica Budha & Backeljau, sp. n., R. nagarjunensis Budha & Naggs, sp. n., R. rishikeshi Budha & Naggs, sp. n., R. subulata Budha & Naggs and R. tribhuvana Budha, sp. n. and two are new records for Nepal viz. G. cf. hebetata and R. cf. mastersi. The relation between the shell height-width ratio and the structure of the proximal part of the male reproductive organs in Glessulinae is explored. Illustrations and a key for the identification of the Nepalese Glessulinae are provided, including the first record of a spermatophore in Rishetia.

Background. Invasive species are among the most significant threats to biodiversity. The diet of invasive animal populations is a crucial factor that must be considered in the context of biological invasions. A broad dietary spectrum is a frequently cited characteristic of invasive species, allowing them to thrive in a wide range of environments. Therefore, empirical studies comparing diet in invasive and native populations are necessary to understand dietary requirements, dietary flexibility, and the associated impacts of invasive species. Methods. In this study, we compared the diet of populations of the African clawed frog, Xenopus laevis in its native range, with several areas where it has become invasive. Each prey category detected in stomach contents was assigned to an ecological category, allowing a comparison of the diversity of ecological traits among the prey items in the diet of native and introduced populations. The comparison of diets was also performed using evenness as a niche breadth index on all sampled populations, and electivity as a prey selection index for three out of the six sampled populations. Results. Our results showed that diet breadth could be either narrow or broad in invasive populations. According to diet and prey availability, zooplankton was strongly preferred in most cases. In lotic environments, zooplankton was replaced by benthic preys, such as ephemeropteran larvae. Discussion. The relative proportions of prey with different ecological traits, and dietary variability within and between areas of occurrence, suggest that X. laevis is a generalist predator in both native and invasive populations. Shifts in the realized trophic niche are observed, and appear related to resource availability. Xenopus laevis may strongly impact aquatic ecosystems because of its near complete aquatic lifestyle and its significant consumption of key taxa for the trophic relationships in ponds.

Imagine a future where dynamically, from year to year, we can track the progression of alien species (AS), identify emerging problem species, assess their current and future risk and timely inform policy in a seamless data-driven workflow. One that is built on open science and open data infrastructures. By using international biodiversity standards and facilities, we would ensure interoperability, repeatability and sustainability. This would make the process adaptable to future requirements in an evolving AS policy landscape both locally and internationally. In recent years, Belgium has developed decision support tools to inform invasive alien species (IAS) policy, including information systems, early warning initiatives and risk assessment protocols. However, the current workflows from biodiversity observations to IAS science and policy are slow, not easily repeatable, and their scope is often taxonomically, spatially and temporally limited. This is mainly caused by the diversity of actors involved and the closed, fragmented nature of the sources of these biodiversity data, which leads to considerable knowledge gaps for IAS research and policy. We will leverage expertise and knowledge from nine former and current BELSPO projects and initiatives: Alien Alert, Invaxen, Diars, INPLANBEL, Alien Impact, Ensis, CORDEX.be, Speedy and the Belgian Biodiversity Platform. The project will be built on two components: 1) The establishment of a data mobilization framework for AS data from diverse data sources and 2) the development of data-driven procedures for risk evaluation based on risk modelling, risk mapping and risk assessment. We will use facilities from the Global Biodiversity Information Facility (GBIF), standards from the Biodiversity Information Standards organization (TDWG) and expertise from Lifewatch to create and facilitate a systematic workflow. Alien species data will be gathered from a large set of regional, national and international initiatives, including citizen science with a wide taxonomic scope from marine, terrestrial and freshwater environments. Observation data will be funnelled in repeatable ways to GBIF. In parallel, a Belgian checklist of AS will be established, benefiting from various taxonomic and project-based checklists foreseen for GBIF publication. The combination of the observation data and the checklist will feed indicators for the identification of emerging species; their level of invasion in Belgium; changes in their invasion status and the identification of areas and species of concern that could be impacted upon by bioinvasions. Data-driven risk evaluation of identified emerging species will be supported by niche and climate modelling and consequent risk mapping using critical climatic variables for the current and projected future climate periods at high resolution. The resulting risk maps will complement risk assessments performed with the recently developed Harmonia+ protocol to assess risks posed by emergent species to biodiversity and human, plant, and animal health. The use of open data will ensure that interested stakeholders in Belgium and abroad can make use of the information we generate. The open science ensures everyone is free to adopt and adapt the workflow for different scenarios and regions. The checklist will be used at national level, but will also serve as the Belgian reference for international databases (IUCN - GRIIS, EASIN) and impact assessments (IPBES, SEBI). The workflow will be showcased through GEO BON, the Invasivesnet network and the COST Actions Alien Challenge and ParrotNet. The observations and outcomes of risk evaluations will be used to provide science-based support for the implementation of IAS policies at the regional, federal and EU levels. The publication of Belgian data and checklists on IAS is particularly timely in light of the currently ongoing EU IAS Regulation and its implementation in Belgium. By proving that automated workflows can provide rapid and repeatable production of information, we will open up this technology for other conservation assessments.

A new species of the recently re-established genus Tenguella is described from the Sultanate of Oman. It is compared with three of the four species included in this genus: Tenguella granulata (Duclos, 1832), the type species and a common species occurring in the Indo-Pacific, Tenguella ceylonica (Dall, 1923) known from south-eastern India to the Philippines and Tenguella marginalba (Blainville, 1832) from eastern Australia.

En Mauritanie occidentale, le site de Nouadhfat, au nord-est de Nouakchott, est essentiel, tant pour la connaissance des paléoenvironnements holocènes que pour celle du Néolithique. Le site se trouve à proximité d’un important paléoréseau hydrographique et sur le rivage d’un vaste paléolac marqué par des diatomites, des gastéropodes d’eau douce et des pistes animales imprimées dans la boue. L’habitat fut occupé par des chasseurs-cueilleurs, des pêcheurs (présence de harpons) et des éleveurs, qui profitèrent d’un milieu évoluant progressivement vers moins d’humidité : une première fois au Néolithique moyen (autour de 6400 cal. BP), puis plus récemment (3900 – 3300 cal. BP), après une crise aride très marquée. Nouadhfat, qui est le site le mieux daté de la région, s’inscrit dans un ensemble d’une grande richesse sur au moins quatre millénaires. La caractéristique principale de ce groupe est sans doute l’existence de nombreuses cultures, qui se sont succédé ou ont cohabité, avant que la limite septentrionale du Sahel ne se décale nettement vers le sud.