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International audience; Crickets (Ensifera, Grylloidea) are not commonly used as ecological indicators in contrary to other Orthoptera (e.g., grasshoppers and katydids). However, they are sensitive to environmental changes and abundant in tropical regions. To evaluate whether crickets are relevant bioindicators of tropical ecosystems, we investigated cricket assemblages along a tropical ecological gradient. We collected crickets during both day and night in southern New Caledonia for three stages of ecological succession: open shrubland, preforest, and forest. Simultaneously, we measured several environmental variables, such as temperature and relative humidity, at each sampling site. Cricket species assemblages showed a clear response to ecological succession. The highest and lowest species richness and abundances of individuals were, respectively, found in forest and shrubland, with species specialized in each ecological stage revealing the conservation value of each of these stages. Similar results were found when considering only the part of cricket communities with the ability to acoustically communicate. This work is part of a larger research program about Neocaledonian crickets and contributes to support the use of acoustic approaches to monitor tropical environments. In conclusion, these findings highlight the potential value of crickets as an environmental indicator in tropical ecosystems. The results also contribute to the discussion of the intrinsic conservational value of shrublands in New Caledonia and similar ecotypes.; Bien que d’autres groupes d’orthoptères soient largement utilisés comme bioindicateur, les grillons sont peu considérés dans les études écologiques. Pourtant, les grillons sont à la fois sensibles aux changements environnementaux et très abondants dans les régions tropicales. Dans cette étude, nous avons décrit les assemblages de grillons le long d’un gradient écologique en milieu tropical. Nous avons collecté les individus en période nocturne et diurne, sur 12 sites, et dans trois formations végétales du Sud de la Nouvelle Calédonie : le maquis, le paraforestier et le forestier. Des variables environnementales comme la température et l’humidité relative ont été collectées simultanément aux relevés de grillons. Les assemblages de grillons montrent une réponse très claire à la succession environnementale, suivant le gradient écologique, avec une diversité d’espèce et une abondance d’individus plus élevées en milieu forestier qu’en milieu maquis. Chaque stade du gradient écologique montre un assemblage unique d’espèces. Des résultats similaires sont obtenus en ne considérant que la part de la communauté des grillons qui utilisent l’acoustique pour communiquer. Ces résultats, interprétés à la lumière de travaux complémentaires faisant parties du même programme de recherche sur les grillons de Nouvelle-Calédonie, supporte l’analyse de relevés acoustiques pour évaluer l’état des milieux. En conclusion, les résultats soutiennent l’intérêt des grillons comme indicateurs écologiques du milieu tropical. Ces résultats contribuent également à la reconnaissance de la valeur intrinsèque des maquis en terme de conservation de la biodiversité en Nouvelle-Calédonie et dans des écotypes similaires.

The little fire ant, Wasmannia auropunctata, is an invasive species known to negatively affect many native species in its introduced range. Here, we studied the effect of little fire ant presence on the biomass of soil fauna in rainforest of New Caledonia to assess if little fire ants have an impact on an endangered endemic flightless bird, the kagu, Rhynochetos jubatus. The average biomass of soil fauna (except for millipedes) was lower in 53 sample plots with little fire ants than in 597 sample plots without little fire ants and the biomass decreased with increasing density of little fire ant nests. Millipedes on the contrary seemed to be positively impacted as their average biomass was higher in areas with fire ants than in areas without, but even millipede biomass decreased with increasing nest density of fire ants. Kagu density decreased with increasing area of rainforest invaded by little fire ants, suggesting, given their observed negative impact on soil fauna biomass, that they may limit food resources for kagu. Little fire ants might therefore transform rainforest into a less suitable habitat for the kagu by reducing the biomass of their prey and thus have a negative impact for kagu conservation.

New Caledonia was, until recently, considered an old continental island harbouring a rich biota with outstanding Gondwanan relicts. However, deep marine sedimentation and tectonic evidence suggest complete submergence of the island during the latest Cretaceous to the Paleocene. Molecular phylogenies provide evidence for some deeply-diverging clades that may predate the Eocene and abundant post-Oligocene colonisation events. Extinction and colonization biases, as well as survival of some groups in refuges on neighbouring paleo-islands, may have obscured biogeographic trends over long time scales. Fossil data are therefore crucial for understanding the history of the New Caledonian biota, but occurrences are sparse and have received only limited attention. Here we describe five exceptional fossil assemblages that provide important new insights into New Caledonia’s terrestrial paleobiota from three key time intervals: prior to the submersion of the island, following re-emergence, and prior to Pleistocene climatic shifts. These will be of major importance for elucidating changes in New Caledonia’s floristic composition over time.

The OCBIL theory comprises a set of hypotheses to comprehend the biota of old, climatically buffered, infertile landscapes (OCBILs). Here, we review evidence from the literature to evaluate the extent to which this theory could apply to the biodiversity hotspot of New Caledonia. We present geological, pedological and climatic evidence suggesting how the island might qualify as an OCBIL. The predictions of OCBIL theory are then reviewed in the context of New Caledonia. There is evidence for a high rate of micro-endemism, accumulation of relict lineages, a high incidence of dioecy, myrmecochory and nutritional specializations in plants. New Caledonian vegetation also exhibits several types of monodominant formations that reveal the importance of disturbances on the island. Fires and tropical storms are likely to be important factors that contribute to the dynamic of New Caledonian ecosystems. Although naturally infertile, there is archaeological evidence that humans developed specific horticultural practices in the ultramafic landscapes of New Caledonia. Further comparisons between New Caledonia and other areas of the world, such as South Africa and Southwest Australia, are desirable, to develop the OCBIL theory into a more robust and generalized, testable framework and to determine the most efficient strategies to preserve their outstanding biodiversity.

International audience; Thirty-three species of aphids are now established in New Caledonia. All species appear to have been introduced accidentally by human activity in the last century. Here, 17 aphid species are recorded for the first time: Aphis eugeniae, Aphis glycines, Aphis odinae, Aulacorthum solani, Brachycaudus helichrysi, Cerataphis orchidearum, Greenidea psidii, Hyperomyzus carduellinus, Hysteroneura setariae, Lipaphis pseudobrassicae, Micromyzus katoi, Myzus ornatus, Pentalonia caladii, Rhopalosiphum nymphaeae, Rhopalosiphum rufiabdominale, Schizaphis rotundiventris, and Tetraneura fusiformis. Thirteen more species are also more or less regularly intercepted at the borders through biosecurity surveys, without further establishment. This demonstrates that aphids represent a major biosecurity threat, including a threat as potential plant virus vectors. The reinforcement of biosecurity is a priority for such biodiversity hotspots, from the perspectives of both agriculture and the native environment. Prioritisation and promotion of local development of vegetable and fruit production, rather than their risky importation from abroad, is desirable. Such an approach also should be promoted and extended to other Pacific islands, which all share the lack of native aphid fauna and their associated plant disease vector risks.; Trente trois (33) espèces de pucerons sont aujourd’hui recensées de Nouvelle-Calédonie. Toutes ces espèces sont exotiques et ont été introduites accidentellement par les activités humaines. Dix-sept (17) espèces y sont ainsi recensées pour la première fois : Aphis eugeniae, Aphis glycines, Aphis odinae, Aulacorthum solani, Brachycaudus helichrysi, Cerataphis orchidearum, Greenidea psidii, Hyperomyzus carduellinus, Hysteroneura setariae, Lipaphis pseudobrassicae, Micromyzus katoi, Myzus ornatus, Pentalonia caladii, Rhopalosiphum nymphaeae, Rhopalosiphum rufiabdominale, Schizaphis rotundiventris et Tetraneura fusiformis. Par ailleurs, au moins 13 autres espèces sont régulièrement interceptées par la biosécurité sans établissement actuel de populations. Les pucerons apparaissent donc comme une menace croissante pour la biosécurité de l’archipel. Aussi, le renforcement des mesures de biosécurité aux frontières apparaît prioritaire en association à une promotion du développement local de productions maraîchères et fruitières. Ainsi, la limitation de ces importations à risque, devrait contribuer à une meilleure protection des productions agricoles et de la biodiversité. Une telle approche devrait également être promue dans les pays insulaires du Pacifique, qui se caractérisent par la même disharmonie de peuplements, l’absence de communautés natives de pucerons et du risque associé de vectorisation de maladies phytopathogènes.

Land-use changes through urbanization and biological invasions both threaten plant-pollinator networks. Urban areas host modified bee communities and are characterized by high proportions of exotic plants. Exotic species, either animals or plants, may compete with native species and disrupt plant&ndash, pollinator interactions. These threats are heightened in insular systems of the Southwest Pacific, where the bee fauna is generally poor and ecological networks are simplified. However, the impacts of these factors have seldom been studied in tropical contexts. To explore those questions, we installed experimental exotic plant communities in urban and natural contexts in New Caledonia, a plant diversity hotspot. For four weeks, we observed plant&ndash, pollinator interactions between local pollinators and our experimental exotic plant communities. We found a significantly higher foraging activity of exotic wild bees within the city, together with a strong plant&ndash, pollinator association between two exotic species. However, contrary to our expectations, the landscape context (urban vs. natural) had no effect on the activity of native bees. These results raise issues concerning how species introduced in plant&ndash, pollinator networks will impact the reproductive success of both native and exotic plants. Furthermore, the urban system could act as a springboard for alien species to disperse in natural systems and even invade them, leading to conservation concerns.

International audience; A new genus and species of skink, Kuniesaurus albiauris, is here described from the Île des Pins off southern New Caledonia. This new taxon possesses a unique suite of morphological apomorphies (scalation) that does not allow it to be placed in any existing Australasian eugongylid genus. It is known only from a single area in dense coastal forest on limestone, on the main island of the Île des Pins. The species area of occupancy is restricted, and the habitat occupied under threat from the spread of the highly invasive Little Red Fire Ant Wasmannia auropunctata. These factors place this new skink at a level of risk sufficient for it to be listed as Critically Endangered under IUCN Red List criteria. The affinities of the lizard fauna of the Île des Pins with respect to that present on southern New Caledonia are also discussed, most notably the absence from the Île des Pins of taxa typically restricted to ultramafic surfaces.

Atelier Biodiversité en Océanie, Nouméa, NCL, 24-/06/2019 - 25/06/2019; Face à l’urgence de préserver la biodiversité, les aires protégées répondent à la nécessité d’appliquer un principe de précaution (valeur d’option) sur le vivant et son évolution à l’échelle mondiale. Dans le contexte océanien, pour être efficace en matière de préservation de la biodiversité et être soutenu socialement et politiquement, il est incontournable d’articuler l’agenda mondial de lutte contre l’effondrement de la biodiversité à la préservation des modes de vie locaux et des services que les populations tirent de la biodiversité.Préserver la biodiversité et les services écosystémiques à travers les aires protégées doit consolider la contribution de la nature au bien-être des Océaniens.

Workshop Biodiversity in Oceania, Nouméa, NCL, 24-/06/2019 - 25/06/2019; As we are facing the urgency of safeguarding biodiversity, protected areas address the need to apply a precautionary principle (option value) to living things and their evolution at a global scale. In Oceania, for effective, socially and politically sustainable conservation of biodiversity, it is essential to reconcile the global agenda, designed to prevent the collapse of biodiversity, with the preservation of local lifestyles and the services that people get from biodiversity. Preserving biodiversity and ecosystem services using protected areas must consolidate Nature's contribution to the well-being of Oceanians.

International audience; Compared to other archipelagos of the Pacific, the New Caledonian Odonata fauna is rich and diverse with 56 valid species or subspecies (23 endemics, 41%) from eight families (four Zygoptera: Argiolestidae, Coenagrionidae, Isostictidae, Lestidae, and four Anisoptera: Aeshnidae, Corduliidae, Synthemistidae, Libellulidae) and 31 genera (including four endemics, 13%). In Zygoptera, we record 19 species including 12 endemics (63%), and among Anisoptera, we record 37 species or subspecies, including 11 endemics (30%). we removed five species from the list that had been erroneously recorded also doubtful, but we were unable to clarify to which taxon this record referred hence we excluded it from our update. From a biogeographic perspective, the New Caledonian fauna has mostly Australian affinities with some connections with southeast Asia and the Pacific region. we provide for each species, whenever information was available, a distribution map with a brief review of its known ecology, behaviour and phenology. we also evaluated each species' conservation status, in light of known threats (range restriction, scarcity and human activity including altered water flow). we consider seventeen species (30%) endangered. The most immediate threats concern water pollution including alteration to the flow of water courses caused by mining, deforestation and fires. Invasive species, such as alien fish, may be predators of concern for odonata larva, although this has not yet been proven in New Caledonia.; Par rapport aux autres archipels du Pacifique, la faune des Odonates de Nouvelle-Calédonie est riche et diversifiée avec 56 espèces ou sous-espèces valides (23 espèces endémiques, 41 %) de huit familles (quatre de Zygoptères: Argiolestidae, Coenagrionidae, Isostictidae, Lestidae et quatre d'Anisoptères: Aeshnidae, Corduliidae, Synthemistidae, Libellulidae) et 31 genres (dont quatre endémiques, 13 %). Parmi les Zygoptères, nous comptons 19 taxa dont 12 endémiques (63%). Parmi les Anisoptères, nous comptons 37 espèces ou sous-espèces, dont 11 endémiques (30%). Nous avons retiré 5 espèces de la liste faunistique de Nouvelle-Calédonie, celles-ci ayant été attribuées de façon erronée à l'archipel: une mention douteuse et n'a pas été incluse dans cet inventaire, faute d'une clarification de l'identité du taxon concerné. Cette faune montre de très nettes affinités biogéografiques avec l'Australie, avec quelques influences du sud-est asiatique et de la région Pacifique. Pour chaque espèce, nous proposons une carte de distribution et une synthèse des données disponibles sur l'écologie, l'éthologie et la phénologie. Pour chacune des espèces, nous proposons une évaluation du niveau de menaces (en fonction de leur distribution, de leur rareté et des menaces consécutives aux activités humaines) et un statut provisoire. Dix-sept espèces (30%) sont considérées en danger d'extinction. Les menaces les plus immédiates concernent la pollution des cours d'eau notamment par l'activité minière, la déforestation et les incendies qui changent le régime d'écoulements des cours d'eau. Des espèces envahissantes, comme les poissons exotiques, peuvent être prédateurs importants pour les larves d'odonates, bien que cela n' aie pas encore été prouvé en Nouvelle Calédonie.

International audience; We provide an up-to-date catalogue of the Coccomorpha Rubsaamen, 1899 of New Caledonia based on studies of collected and curated specimens and on the literature. One hundred and eighteen species (118) in ten families have been recorded to date, in 70 genera. Five of the genera (7.2%) are endemic, belonging to Asterolecaniidae Berlese, 1898 (Oacoccus Williams, 2007), Eriococcidae Cockerell, 1899 (Chazeauana Matile-Ferrero, 1988, Choneochiton Hodgson, 2014) and Monophlebidae Maskell, 1880 (Insulococcus Bhatti, 1991, Tessarobelus Montrouzier, 1864). Twenty-nine (29) species are endemic to New Caledonia, giving a rate of endemism of 24.6%. Most of the species are apparently human-assisted introductions. We provide here first records from New Caledonia for ten (10) species: Aulacaspis rosarum Borchsenius, 1858; Chrysomphalus pinnulifer (Maskell, 1891); Diaspis echinocacti (Bouche, 1833); Fiorinia phantasma (Cockerell & Robinson, 1915); Labidaspis myersi Green, 1929; Palmicultor browni (Williams, 1960); Poliaspoides formosana (Takahashi, 1930); Pseudococcus gilbertensis Beardsley, 1966; Pseudococcus orchidicola Takahashi, 1939 and Rhizoecus cacticans (Hambleton, 1946). Despite two introduction attempts for the biological control of weedy cactus, Hypogeococcus festerianus (Lizer y Trelles, 1942) is still considered absent from New Caledonia. Literature records of five species are shown to be erroneous: Dactylopius tomentosus (Lamarck, 1801); Dysmicoccus cocotis (Maskell, 1890); Lindingaspis buxtoni (Laing, 1927); Nipaecoccus filamentosus (Cockerell, 1893) and Clavaspis herculeana (Cockerell & Hadden, in Doane & Hadden, 1909), which are therefore considered absent from New Caledonia.

International audience

International audience; Invasive alien species are a major threat to native insular species. Eradicating invasive mammals from islands is a feasible and proven approach to prevent biodiversity loss. We developed a conceptual framework to identify globally important islands for invasive mammal eradications to prevent imminent extinctions of highly threatened species using biogeographic and technical factors, plus a novel approach to consider socio-political feasibility. We applied this framework using a comprehensive dataset describing the distribution of 1,184 highly threatened native vertebrate species (i.e. those listed as Critically Endangered or Endangered on the IUCN Red List) and 184 non-native mammals on 1,279 islands worldwide. Based on extinction risk, irreplaceability, severity of impact from invasive species, and technical feasibility of eradication, we identified and ranked 292 of the most important islands where eradicating invasive mammals would benefit highly threatened vertebrates. When socio-political feasibility was considered, we identified 169 of these islands where eradication planning or operation could be initiated by 2020 or 2030 and would improve the survival prospects of 9.4% of the Earth’s most highly threatened terrestrial insular vertebrates (111 of 1,184 species). Of these, 107 islands were in 34 countries and territories and could have eradication projects initiated by 2020. Concentrating efforts to eradicate invasive mammals on these 107 islands would benefit 151 populations of 80 highly threatened vertebrates and make a major contribution towards achieving global conservation targets adopted by the world’s nations.

International audience

International audience; Invasive species are a major concern for the maintenance of ecosystem services and biodiversity but are difficult to mitigate. Upstream solutions to prevent their impact, including their detection, are needed. Wasmannia auropunctata, an invasive ant living in vagile supercolonies, is especially hard to track and is a major threat for tropical ecosystems and local animal communities. As part of such tropical communities, crickets are sensitive to ecological conditions, easy to collect, detectable and identifiable through their species-specific calls. Here, we evaluated the use of an acoustic community of crickets as an indicator of the presence of W. auropunctata in New Caledonia. We evaluated the dominance of the crickets in the soundscape, describe the cricket community structure and diversity along a shrubland to forest gradient, characterize these cricket communities structure and diversity in the light of ongoing invasion by W. auropunctata, and identify cricket species' indicators of the invasion. Acoustic recordings collected on 24 sites were described using human-listening and spectrographic visualization. The results demonstrated a clear dominance of the cricket group in the New Caledonian nocturnal soundscapes. Each habitat harbored a specific acoustic cricket community related to specific environmental attributes including vegetation height, daily variation of humidity and temperature. The presence of W. auropunctata was significantly associated with a lower cricket acoustic activity and species richness at night. Of the 19 species detected, four nocturnal species were identified as indicator of non-invaded forests and preforests. This work supports the use of acoustic as an alternative method to detect invasion.

International audience

International audience; Squamata are one of the most threatened groups among island vertebrates, facing high pressure from exotic species. However, the contribution of small terrestrial reptiles in invasive rodents' diet remains poorly investigated, partly because of the lack of tools for accurately identifying chewed prey fragments in gut contents. The New Caledonia archipelago (South Pacific) hosts an exceptional terrestrial squamata fauna (105 species, 91.6% endemic) that are faced with many invasive species (rodents, feral cats, feral pigs, ants) and strong human pressures. Our study aimed to evaluate the frequency of occurrence of endemic skink remains by gut content analysis of two species of invasive rodents. Four rodent trapping sessions were implemented at two ultramafic sites and for two distinct habitats (closed canopy forest and open shrubland habitat). A total of 284 rats were trapped from two species (the ship rat Rattus rattus and the Pacific rat R. exulans) over 1200 trap nights. Combined analysis of stomach and caecum contents provided far more information than traditional stomach analysis alone. Analyses showed that 15.9% of rat samples included remains of at least 12 different skink species out of the 23 present. Six species are classified as threatened by the IUCN, the most endangered being Marmorosphax taom (CR) and Kanakysaurus viviparus (EN). This study provides new prospects for the assessment of invasive rodent impacts and new insights into the respective impacts of two sympatric invasive rodent species on native skinks.

Insect diversity represents about 60% of the estimated million-and-a-half described eukaryotic species worldwide, yet comprehensive and well-resolved intra-ordinal phylogenies are still lacking for the majority of insect groups. This is the case especially for the most species-rich insect group, the beetles (Coleoptera), a group for which less than 4% of the known species have had their DNA sequenced. In this study, we reconstruct the first higher level phylogeny based on DNA sequence data for the species-rich darkling beetles, a family comprising at least 20 000 species. Although amongst all families of beetles Tenebrionidae ranks seventh in terms of species diversity, the lack of knowledge on the phylogeny and systematics of the group is such that its monophyly has been questioned (not to mention those of the subfamilies and tribes contained within it). We investigate the evolutionary history of Tenebrionidae using multiple phylogenetic inference methods (Bayesian inference, maximum likelihood and parsimony) to analyse a dataset consisting of eight gene fragments across 404 taxa (including 250 tenebrionid species). Although the resulting phylogenetic framework only encompasses a fraction of the known tenebrionid diversity, it provides important information on their systematics and evolution. Whatever the methods used, our results provide strong support for the monophyly of the family, and highlight the likely paraphyletic or polyphyletic nature of several important tenebrionid subfamilies and tribes, notably the polyphyletic subfamilies Diaperinae and Tenebrioninae that clearly require substantial revision in the future. Some interesting associations in several groups are also revealed by the phylogenetic analyses, such as the pairing of Aphtora Bates with Phrenapatinae. Furthermore this study advances our knowledge of the evolution of the group, providing novel insights into much-debated theories, such as the apparent relict distribution of the tribe Elenophorini.

Crickets (Insecta, Orthoptera, Gryllidea) are amongst the most abundant and diverse insects in New Caledonia: 40 genera are recorded today from the Archipelago and 180 cricket species have been reported; 19 genera and more than 90% of the species are endemic. Owing to this diversity, crickets prove an interesting model to test evolutionary hypotheses about New Caledonia and its fauna. They also reveal useful ecological indicators to survey and manage New Caledonian biodiversity. Both research and conservation developments need however that crickets are properly identified. In the present paper, an illustrated key to the identification of New Caledonian cricket genera is proposed, based on specimen examination; an emended diagnosis is given for each genus, using general morphology, coloration and the main traits of male genitalia, together with available data on habitat and biology. The genus Paora Gorochov, 1986 n. stat. is restored from its synonymy with Apteronemobius Chopard, 1929, Trigonidomo...

The new genus Murmurillana Delorme gen. nov., is described within the tribe Cicadettini Buckton, 1889, designating Murmurillana inaudibilis Delorme sp. nov., as the type species. Murmurillana inaudibilis Delorme sp. nov. and Murmurillana paenetacita Delorme sp. nov. are described from New Caledonia. They are respectively found in mid altitude dense Niaouli shrub (Melaleuca quinquenervia, Myrtaceae) vegetation, mixed with dense fern cover (Pteridium sp., Dennstaedtiaceae) on the Massif of Aoupinié (800 m) and on foothills of the Mont Panié (570 m). Male calling songs of the two new species are described from field recordings. These calling songs exhibit unusually high dominant frequencies. A key to the species of Murmurillana Delorme gen. nov., is also provided.

Intensive sampling of cricket communities has been undertaken in southern New Caledonia in selected plots of vegetation, i.e. rain forest, preforest and maquis shrubland. This leads to the discovery of many new taxa, which are described in the present paper, together with closely related species from nearby areas. Descriptions are based on general morphology and characters of genitalia. Calling songs are described for all acoustic taxa but two, and observations about species habitats are given. In total, 35 species belonging to 13 genera are studied, including 21 new species and two new genera. The pattern of assemblages of cricket species in New Caledonia is discussed.

Among invasive species, ants are a particularly prominent group with enormous impacts on native biodiversity and ecosystem functioning. Globalization and on-going climate change are likely to increase the rate of ant invasions in the future, leading to simultaneous introductions of several highly invasive species within the same area. Here, we investigate pairwise interactions among four highly invasive species, Linepithema humile, Lasius neglectus, Pheidole megacephala and Wasmannia auropunctata, at the whole colony level, using a laboratory set-up. Each colony consisted of 300 workers and one queen. The number of surviving workers in the competing colonies was recorded daily over 7 weeks. We modelled the survival of each colony during pairwise colony interactions, using a nonlinear model characterizing the survival dynamics of each colony individually. The least dominant species was P. megacephala, which always went extinct. Interactions among the three other species showed more complex dynamics, rendering the outcome of the interactions less predictable. Overall, W. auropunctata and L. neglectus were the most dominant species. This study shows the importance of scaling up to the colony level in order to gain realism in predicting the outcome of multiple invasions., This paper was supported by Région Ile-de-France (03-2010/GV-DIM ASTREA), ANR (2009 PEXT 010 01) and BiodivERsa Eranet grants, FFII Project.

International audience; Among New Caledonian cicada taxa, the endemic genus Kanakia Distant, 1892 appears as the most spectacular one, especially because of the large size of its species (length up to 50 mm for males). Recent new specimen collections helped to clarify the taxonomy of this spectacular genus. According to morphological characteristics, we were able to redefine and to split the present genus into three distinct genera: Kanakia Distant, 1892, Pseudokanakia Delorme gen. nov. and Panialna Delorme gen. nov. These two new genera are monotypic and have been respectively established from revision of Kanakia flavoannulata (Distant 1920) and Kanakia parva Boulard 1991. Also, the type species, Kanakia typica Distant, 1892, appears to be a complex of cryptic species. New acoustic and morphological observations allowed us to redefine K. typica and to describe four new species in this complex: Kanakia paniensis Delorme sp. nov., Kanakia rana Delorme sp. nov., Kanakia salesnii Delorme sp. nov. and Kanakia fuscocosta Delorme sp. nov. Kanakia gigas Boulard 1988 is also briefly discussed and the female is described. An identification key of the Kanakia species and allied genera is also provided.

International audience; Few studies have focused on the early colonization of New Caledonia by insects, after the re-emergence of the main island, 37 Myr ago. Here we investigate the mode and tempo of evolution of a new endemic cricket genus, Pixibinthus, recently discovered in southern New Caledonia. First we formally describe this new monotypic genus found exclusively in the open shrubby vegetation on metalliferous soils, named 'maquis minier', unique to New Cal-edonia. We then reconstruct a dated molecular phylogeny based on five mitochondrial and four nuclear loci in order to establish relationships of Pixibinthus within Eneopterinae crickets. Pixibinthus is recovered as thesister clade of the endemic genus Agnotecous, mostly rainforest-dwellers. Dating results show that the island colonization by their common ancestor occurred around 34.7 Myr, shortly after New Caledonia re-emergence. Pixibinthus and Agnotecous are then one of the oldest insect lineages documented so far for New Caledo-nia. This discovery highlights for the first time two clear-cut ecological specializations between sister clades, as Agnotecous is mainly found in rainforests with 19 species, whereas Pixibinthus is found in open habitats with a single documented species. The preference of Pixibinthus for open habitats and of Agnotecous for forest habitats nicely fits an acoustic specialization, either explained by differences in body size or in acoustic properties of their respective habitats. We hypothesize that landscape dynamics, linked to major past climatic events and recent change in fire regimes are possible causes for both present-day low diversity and rarity in genus Pixibinthus. The unique evolutionary history of this old New Caledonian lineage stresses the importance to increase our knowledge on the faunal biodiversity of 'maquis minier', in order to better understand the origin and past dynamics of New Caledonian biota.

International audience; The impact of alien predator species on insular native biota has often been attributed to island prey naïveté (i.e. lack of, or inefficient, anti-predator behavior). Only rarely, however, has the concept of island prey naïveté been tested, and then only a posteriori (i.e. hundreds or thousands of years after alien species introduction). The presence of native or anciently introduced predators or competitors may be crucial for the recognition and development of adaptive behavior toward unknown predators or competitors of the same archetype (i.e. a set of species that occupy a similar ecological niche and show similar morphological and behavioral traits when interacting with other species). Here, we tested whether two squa-mates endemic to New Caledonia, a skink, Caledoniscincus austrocaledonicus, and a gecko, Bavayia septuiclavis, recognized and responded to the odor of two major invaders introduced into the Pacific islands, but not yet into New Caledonia. We chose one predator, the small Indian mongoose Herpestes javanicus and one competitor, the cane toad Rhinella marina, which belong respectively to the same archetype as the following two species already introduced into New Caledonia in the nineteenth century: the feral cat Felis catus and the golden bell frog Litoria aurea. Our experiment reveals that geckos are naïve with respect to the odors of both an unknown predator and an unknown competitor, as well as to the odors of a predator and a competitor they have lived with for centuries. In contrast, skinks seem to have lost some naïveté regarding the odor of a predator they have lived with for centuries and seem " predisposed " to avoid the odor of an unknown potential competitor. These results indicate that insular species living in contact with invasive alien species for centuries may be, although not systematically, predisposed toward developing adaptive behavior with respect to species belonging to the same archetype and introduced into their native range.

In November 2007 and November 2008, we conducted a bird and mammal survey on Wallis and Futuna. We found two non-native bird species on Wallis: the Common Myna (Acridotheres tristis) and the Chestnut-breasted Munia (Lonchura castaneothorax), and one on Futuna: the Jungle Myna (Acridotheres fuscus). We also recorded Black Rats (Rattus rattus) on Futuna, a recent introduction to this island. The introduction of 3 bird species and Black Rats in the last decade denotes a lack of preventive measures and demonstrates that the issue of invasive species has not received sufficient priority.

Biological invasions are generally thought to occur after human aided migration to a new range. However, human activities prior to migration may also play a role. We studied here the evolutionary genetics of introduced populations of the invasive ant Wasmannia auropunctata at a worldwide scale. Using microsatellite markers, we reconstructed the main routes of introduction of the species. We found three main routes of introduction, each of them strongly associated to human history and trading routes. We also demonstrate the overwhelming occurrence of male and female clonality in introduced populations of W. auropunctata, and suggest that this particular reproduction system is under selection in human-modified habitats. Together with previous researches focused on native populations, our results suggest that invasive clonal populations may have evolved within human modified habitats in the native range, and spread further from there. The evolutionarily most parsimonious scenario for the emergence of invasive populations of the little fire ant might thus be a two-step process. The W. auropunctata case illustrates the central role of humans in biological change, not only due to changes in migration patterns, but also in selective pressures over species.

We describe a recent case of presumed redback spider (Latrodectus hasselti) envenomation observed near Noumea in New Caledonia. This is the first local reported case in this archipelago, where L. hasselti is Currently considered a native species. We highlight the challenge of providing appropriate analgesia in this situation and believe that the use of specific redback spider antivenom should be considered in New Caledonia.

International audience; We present an updated checklist of the ladybird beetle fauna of New Caledonia. Fifty species have been tracked from literature and collections, but six should be removed from the list as they represent false records, invalid or unestablished species: Coccinella boletifera Fauvel, Harmonia conformis (Boisduval), Menochilus duodecimpunctatus (Fauvel), Micraspis lineola (Fabricius), Orcus australasiae Boisduval, and Curinus coeruleus (Mulsant). After our investigations, the current described ladybird beetle fauna totals 44 named species, belonging to 18 valid genera. The endemism rate is 47.7% (21 species), with one endemic subgenus, Scymnus (Caledonus). Based on comparisons of the coccinellid faunas of surrounding regions, the New Caledonian fauna has affinities with Australia and Papua New Guinea more than with the rest of the Pacific area. At least 19 species (43.2%) seem to have been introduced by human activities (either deliberately or accidentally).

International audience; Ants figure prominently among the worst invasive species because of their enormous ecological and economic impacts. However, it remains to be investigated which species would be behaviourally dominant when confronted with another invasive ant species, should two species be introduced in the same area. In the future, many regions might have suitable environmental conditions for several invasive ant species, as predicted under climate change scenarios. Here, we explored interactions among several highly invasive ant species, which have been shown to have overlapping suitable areas. The aim of this study was to evaluate the performance in interference competition of seven of the world's worst invasive ant species (Anoplolepis gracilipes, Paratrechina longicornis, Myrmica rubra, Linepithema humile, Lasius neglectus, Wasmannia auropunctata and Pheidole megacephala). We conducted pairwise confrontations, testing the behaviour of each species against each of the six other species (in total 21 dyadic confrontations). We used single worker confrontations and group interactions of 10 versus 10 individuals to establish a dominance hierarchy among these invasive ant species. We discovered two different behavioural strategies among these invasive ants: three species displayed evasive or indifferent behaviour when individuals or groups were confronted (A. gracilipes, Pa. longicornis, M. rubra), while the four remaining species were highly aggressive during encounters and formed a linear dominance hierarchy. These findings contrast with the widespread view that invasive ants form a homogeneous group of species displaying the `invasive syndrome', which includes generally aggressive behaviour. The dominance hierarchy among the four aggressive species may be used to predict the outcome of future competitive interactions under some circumstances. Yet, the existence of several behavioural strategies renders such a prediction less straightforward.

International audience; Ants are among the most problematic invasive species. They displace numerous native species, alter ecosystem processes, and can have negative impacts on agriculture and human health. In part, their success might stem from a departure from the discovery-dominance trade-off that can promote co-existence in native ant communities, that is, invasive ants are thought to be at the same time behaviorally dominant and faster discoverers of resources, compared to native species. However, it has not yet been tested whether similar asymmetries in behavioral dominance, exploration, and recruitment abilities also exist among invasive species. Here, we establish a dominance hierarchy among four of the most problematic invasive ants (Linepithema humile, Lasius neglectus, Wasmannia auropunctata, Pheidole megacephala) that may be able to arrive and establish in the same areas in the future. To assess behavioral dominance, we used confrontation experiments, testing the aggressiveness in individual and group interactions between all species pairs. In addition, to compare discovery efficiency, we tested the species' capacity to locate a food resource in a maze, and the capacity to recruit nestmates to exploit a food resource. The four species differed greatly in their capacity to discover resources and to recruit nestmates and to dominate the other species. Our results are consistent with a discovery-dominance trade-off. The species that showed the highest level of interspecific aggressiveness and dominance during dyadic interactions.

The rarely collected gasteruptiid wasp fauna (Evanioidea: Gasteruptiidae) of New Caledonia is reviewed. Previously only two species of Pseudofoenus (Hyptiogastrinae) were known. Here, we record the subfamily Gasteruptiinae from New Caledonia for the first time and describe three new species of Gasteruption: G. lacoulee Jennings, KrogmannParslow, sp. nov., G. maquis Jennings, KrogmannParslow, sp. nov., and G. sarramea Jennings, KrogmannParslow, sp. nov. An identification key to the Gasteruptiidae of New Caledonia is provided.

International audience; The rarely collected gasteruptiid wasp fauna (Evanioidea: Gasteruptiidae) of New Caledonia is reviewed. Previously only two species of Pseudofoenus (Hyptiogastrinae) were known. Here, we record the subfamily Gasteruptiinae from New Caledonia for the first time and describe three new species of Gasteruption: G. lacoulee Jennings, Krogmann & Parslow, sp. nov., G. maquis Jennings, Krogmann & Parslow, sp. nov., and G. sarramea Jennings, Krogmann & Parslow, sp. nov. An identification key to the Gasteruptiidae of New Caledonia is provided.

International audience; Invasive species usually go through a period of reduced genetic variability due to a bottleneck. The genetic constitution of an invading population should therefore reflect the time since invasion and the number of introduction events. We studied genetic population structure of three rat species occurring sympatrically on the island of Futuna (46km(2)), where they were introduced recently (Rattus rattus), 80-170 years ago (R.norvegicus) and about 3000 years ago (R.exulans). From 2007 to 2012, we trapped 3900 rats during a rodent regulation programme over 20000 trap nights and took 565 rat tissue samples for genetic analyses. By examining genetic variation and spatial distribution of genetic resemblance, we evaluated the consequences of the time after introduction for genetic population structure. Observed heterozygosity, expected heterozygosity, number of alleles and allelic richness generally increased with increasing length of time a species was introduced to the island. The species with longer invasion history had also higher spatial admixture. However, in R.norvegicus, the observed heterozygosity was lower and inbreeding higher than expected by the invasion history. We relate this with the assumption that this species was introduced once or a few times and in low numbers, while R.exulans was intentionally introduced many times by Polynesian navigators and R.rattus had a high chance of being introduced on multiple occasions in recent times.

Assuming that a simple drowning model is applicable to all islands facing future climate change and sea-level rise (SLR), the future existence of up to 12% of islands is said to be compromised – and therefore these should not be considered for active management and protection [1,2]. This includes tropical atolls and their low-lying islands. However, we reject the triage strategy elaborated by Courchamp et al. [1]. Evidence from geology, sedimentology, and oceanography, and from the ecology of invasive species, shows that island conservation, especially of low islands, should remain a priority.