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Résumé Ce guide fournit l’information taxonomique pour les 68 espèces d’oligochètes dulçaquicoles connus à l’heure actuelle au Maghreb, au sens strict, c’est-à-dire la région d’Afrique du nord qui regroupe le Maroc, l’Algérie et la Tunisie. Au niveau du Grand Maghreb, ce guide est potentiellement valable pour la Libye mais pas pour la Mauritanie. Une introduction est faite au milieu dulçaquicole du Maghreb et sa spécificité pour les oligochètes, ainsi qu’une présentation de la biologie et la diversité globale des oligochètes. Les récentes avancées dans le domaine de la nomenclature et de la classification du groupe sont intégrées. Un panorama détaillé des familles maghrébines d’oligochètes est dressé, précédé par des introductions à l’anatomie générale et aux caractères taxonomiques des oligochètes. Les aspects pratiques liés à l’échantillonnage et les techniques de préparation des spécimens et leur conservation sont détaillés, ainsi que les étapes à suivre pour les identifier. Une clé d’identification au niveau spécifique est fournie pour chaque famille, valable uniquement pour les oligochètes connus à l’heure actuelle au Maghreb, mais en précisant les espèces susceptibles d’y être rencontrées en raison de leur distribution biogéographique présente. Enfin, ce guide donne la description d’Aktedrilus yacoubii (Naididae, Phallodrilinae), espèce nouvelle pour la science et le Maghreb. Mots-clés – Clitellata, oligochètes dulçaquicoles, Maghreb, clés d’identification, taxonomie, liste d’espèces, échantillonnage, préparation de spécimens. Abstract This guide provides taxonomical information for the 68 freshwater oligochaete species known to date in Maghreb sensu stricto, namely this region of Northern Africa that includes Morocco, Algeria and Tunisia. At the “Grand Maghreb” level, the guide is potentially valid for Libya as well but not for Mauritania. An introduction to the freshwater environment of Maghreb and its peculiarity vis-à-vis the oligochaetes is given, as well as a presentation of the biology and general diversity of oligochaetes. Recent nomenclatural and classification advances are integrated. A comprehensive overview of Maghrebin oligochaete families is given, preceded by introductions into the general anatomy and taxonomic traits of oligochaetes. Practical aspects of sampling, and techniques of specimen preparation and conservation are detailed, as well as steps required for their identification. An identification key, at the species level, is provided for each family, only valid for oligochaetes presently known from Maghreb; however, species likely to be found in the future, because of their current biogeographic distribution, are also mentioned. Lastly, this guide gives the description of Aktedrilus yacoubii (Naididae, Phallodrilinae), a species new for science and Maghreb. Keywords – Clitellata, freshwater oligochaetes, Maghreb, identification keys, taxonomy, species list, sampling, specimen processing.

1) SUMMARY a) Context The improvement of our understanding of ecological processes and the role of biodiversity in the Southern Ocean ecosystems remains a high priority on the research agenda in today’s changing world and is inextricably linked to sustainable development policies on a global scale. Global environmental changes influence species distributions and consequently the structure of communities and ecosystems. Only advances in our knowledge of the Southern Ocean biodiversity and processes important for ecosystem functioning can allow us to address complex evolutionary and ecological questions and enable estimations of the expected change of the biota distribution and composition. Polar regions experience greater rates of global change than any other region in the world. Their biota are highly adapted to the extreme environment they are living in and appear vulnerable to shifts in environmental conditions. Antarctic marine species are especially more sensitive to temperature variation as their physiology is set to a narrow range of temperatures. Also changes in food quality and quantity, together with other environmental shifts such as in pH of the seawater, are likely to impact densities, biomass and community composition but also functional aspects of the Antarctic biota. Because of the key-role of the Southern Ocean for the global ocean system and the growing impact of global environmental change, it is crucial to establish comprehensive baseline information on Antarctic marine biodiversity as a sound benchmark against which future change can be assessed reliably. It is equally important to understand better the ability of taxa to cope with changes in environmental parameters (temperature, pH, ice cover, food quantity and quality) linked to global change, and this from the individual to the community level. Imperative in this approach is to assess how structural and functional characteristics of the biota may be affected by a changing climate. Finally, advanced integrative spatial modelling of the distribution of key species in relation to environmental conditions is needed to predict the future of the marine ecosystems related to climate change. These aspects are addressed in the Bianzo II project by focusing on benthic organisms and communities, specifically representatives from three different size classes of the zoobenthos: Nematoda (meiobenthos), Amphipoda (macrobenthos) and Echinoidea (megabenthos). These three groups are characterised by a high diversity and many of the well over 4000 Antarctic benthic species described so far (Clarke & Johnston, 2003) belong to these taxa. These three selected benthic taxa are also ecologically important in terms of biomass, their role in biogeochemical cycles (C and N) and the trophic role they fulfil in the benthic ecosystem. Furthermore, they are characterised by different biogeographical and diversity patterns, speciation mechanisms, and reproductive and dispersal strategies. Because of these differences and the intrinsic ecological variability between these taxa, it is difficult to assess the extent to which global change will affect the Antarctic benthos in general. Rarely do biodiversity and ecological studies focus on multiple benthic groups. Yet, combining putative size groups in ecological/biodiversity research is imperative to understand the benthic ecosystem as a complex and interactive unity. b) Objectives Climate change and its complex and interactive chain of associated effects will affect the physiology, distribution, phenology, and ontogeny of many Antarctic benthic organisms, but the resulting changes from the species to the community level remain poorly quantified and understood. Individual species may appear vulnerable to environmental shifts or regime changes, but community and ecosystem responses may not act accordingly. Therefore we investigated the biodiversity and responses of the three representative groups of benthic organisms to climate change effects from individual species, over populations, up to the community level During its first phase (2007-2008), BIANZO II aimed at investigating (1) biodiversity patterns of the Antarctic zoobenthos and their causal processes by focussing on the three selected benthic groups (Work package 1: NOWBIO); Furthermore (2) trophodynamic aspects of each of the benthic groups, and their ability to cope with temperature and temperature-related changes (i.e. food composition and availability) but also the effect of pH of the seawater were on the benthos (Work package 2: DYNABIO). In the second phase (2009-2010) of the project, a joint review paper dealing with the effects of global climate change on the Antarctic zoobenthos is being written, based on the results of experiments, field results and literature data. Information collected in previous studies and in the first two work packages of this project was also used to develop a habitat suitability model in order to identify the drivers of benthic distribution patterns and forecast possible changes of benthic communities related to global change (Work package 3: FOREBIO). c) Conclusions i) NOWBIO (1) Benthic biodiversity in new ice free habitats Due to large-scale ice-shelf disintegration events, the Antarctic Larsen A and B areas along the Eastern Antarctic Peninsula recently became ice-free. Our study is the first one to investigate benthic communities and their response to the collapse of ice shelves in this area. At the time of sampling, meiofauna community structure at the inner stations, most remote from the original ice margin, was not or only slightly influenced by colonization, and might be structured by local environmental conditions. Communities living close to the former ice-shelf edge are believed to be at an intermediate or late stage of succession. Densities and diversity here were comparable to those at other more northern Antarctic stations in the Weddell Sea, whereas they were considerably lower at the inner stations. The three echinoid species collected in Larsen A&B areas are good candidates as pioneering species in a changing marine environment. They are known as indirect developers (or at least non-brooders), consistent with high dispersal capabilities. Moreover, this is congruent with the wide Antarctic distribution of these species. These examples stand in contrast to other Antarctic echinoids which are known as direct developers that brood their young and, accordingly, are supposed to present low dispersal capacities. The three Larsen species also display a ‘generalist’ feeding behaviour which can also be considered a characteristic of pioneering species. Furthermore, the symbiotic communities of echinoids in the Larsen area showed a low diversity and a strong similarity with epibionts present on stones, something which has not been observed in other regions so far. These results suggest that ectosymbioses linked to cidaroids could contribute to benthic colonization of the seafloor in these new ice free areas. The Larsen ice-shelf disintegration also led to the discovery of a low-activity methane seep. The observation of elevated densities, subsurface maxima and high dominance of one nematode species was similar to other cold-seep ecosystems world-wide and suggested a dependence on a chemosynthetic food source. However, stable 13C isotopic signals were indicative of phytoplankton-based feeding. This implied that the community was in transition from a chemosynthetic community to a classic phytodetritus feeding community, a temporary ecotone as it were. The characteristic parthenogenetic reproduction of the dominant species is rather unusual for marine nematodes and may be responsible for the successful colonisation by this single species.

A restudy of Devonian palynological assemblages of samples from the A1-69 borehole, drilled in the Ghadamis Basin, western Libya, North Africa has led to the discovery of numerous well-preserved megaspores amongst abundant miospores, rare acritarchs and rare chitinozoans. Thirteen samples from base to top, 1496 ft (456 m) up to 965 ft (294 m), contain the richest Devonian megaspore assemblages from northwestern Gondwana. The section is dated by a rich diverse miospore assemblage indicating the presence of the upper part of the AD pre-Lem Biozone up to the lower part of the TCo Oppel Zone, ranging from a latest Eifelian or earliest Givetian age up to a latest Givetian or an earliest Frasnian age. Seventeen megaspore taxa have been identified. Among them, two new species (Biharisporites lugardonii and Lagenicula milleri) and four new varieties (Corystisporites acutispinosus var. acutispinosus and var. bullatus, Heliotriletes longispinosus var. longispinosus and var. radiatus) are described. One new possible megaspore species is also described: Verruciretusispora labiosa sp. nov. One core sample (1293 ft, 394 m) contains several specimens of very large megaspores (ca. 1 mm), the largest known from Devonian localities (except for one specimen observed in the Givetian from Belgium). Among the 17 megaspore taxa from Libya, 6 are present on the Euramerican Continent. This observation is in accordance with previous palynological conclusions that favour the absence of palaeogeographic barriers between the Euramerican and Gondwanan continents that are suggested to be grouped together in a “Pre-Pangea” land mass.

De mariene zanden en kleien die in de ruime regio rond Antwerpen aan de oppervlakte komen vormen niet alleen België’s rijkste vindplaats van fossielen, maar staan ook geboekstaafd als een van ‘s werelds meest belanghebbende archieven om het verhaal van de veranderingen in biodiversiteit en klimaat van de laatste 35 miljoen jaar te kunnen reconstrueren. En dit in het bijzonder voor de mollusken (tweekleppigen en zeeslakken), vissen en walvissen. Van deze laatste groep zijn al van oudsher vondsten gemeld. Wel werden deze vaak reusachtige beenderen niet altijd juist geïnterpreteerd. De legende van Reus Antigoon zou zo ontstaan zijn. Het KBIN wenst haar langlopende onderzoek naar de veranderingen in zeespiegel, klimaat en biodiversiteit van de laatste 35 miljoen jaar voort te zetten in de bouwput van de Deurganckdoksluis. De bouwput biedt immers dé unieke gelegenheid het geologische en paleontologische archief verder in detail te bestuderen en te bemonsteren, alsook het natuurwetenschappelijke patrimonium verder aan te vullen. De onderzoekingen in de bouwput van het laatst gegraven dok, nl. het Deurganckdok, hebben immers heel wat nieuwe inzichten en ontdekkingen gebracht. Zo werd er o.a. een ongekend Mioceen zandpakket ontdekt, waarin de resten van een nog niet gekend mangrovebos, een nieuwe molluskenfauna en bijzonder goed bewaarde zeesterren werden ontdekt. Voor de eerste keer werden de Pliocene Zanden van Luchtbal ook op Linkeroever aangetroffen. Slechts één goed bewaard skelet van een baleinwalvis en één schedel van een dolfijn werden geborgen, welke na studie volledig nieuw voor de wetenschap bleken! Het voorbije decennium leverde elk relatief compleet skelet of schedel van een walvisachtige een fundamenteel nieuw inzicht voor de wetenschap. Het is dan ook om die reden dat het KBIN in de bouwput van de Deurganckdoksluis actief naar fossiele beenderen van walvissen wil speuren. Onze ‘target’ is enkele skeletten te kunnen vinden en te bergen. Tegelijkertijd zullen ook de andere fossielgroepen en de sedimenten ruime aandacht krijgen in het kader van enkele lang lopende onderzoeken. Hiervoor is de staalname minder ingrijpend, maar wel een regelmatige aanwezigheid van mensen van het KBIN noodzakelijk.