Diversity dynamics in New Caledonia: towards the end of the museum model?

<p>Abstract</p> <p>Background</p> <p>The high diversity of New Caledonia has traditionally been seen as a result of its Gondwanan origin, old age and long isolation under stable climatic conditions (the museum model). Under this scenario, we would expect species diversification to follow a constant rate model. Alternatively, if New Caledonia was completely submerged after its breakup from Gondwana, as geological evidence indicates, we would expect species diversification to show a characteristic slowdown over time according to a diversity-dependent model where species accumulation decreases as space is filled.</p> <p>Results</p> <p>We reanalyze available datasets for New Caledonia and reconstruct the phylogenies using standardized methodologies; we use two ultrametrization alternatives; and we take into account phylogenetic uncertainty as well as incomplete taxon sampling when conducting diversification rate constancy tests. Our results indicate that for 8 of the 9 available phylogenies, there is significant evidence for a diversification slowdown. For the youngest group under investigation, the apparent lack of evidence of a significant slowdown could be because we are still observing the early phase of a logistic growth (i.e. the clade may be too young to exhibit a change in diversification rates).</p> <p>Conclusions</p> <p>Our results are consistent with a diversity-dependent model of diversification in New Caledonia. In opposition to the museum model, our results provide additional evidence that original New Caledonian biodiversity was wiped out during the episode of submersion, providing an open and empty space facilitating evolutionary radiations.</p

Origine de la biodiversité en Nouvelle-Calédonie (analyse phylogénétique de l'endémisme chez les insectes dictyoptères)

Dans le but d analyser l origine de l endémisme en Nouvelle-Calédonie, l histoire évolutive des Insectes Blattidae (Hexapodes, Dictyoptères) a été reconstruite au niveau moléculaire par l application de différentes méthodes phylogénétiques. Les différents résultats obtenus, aux niveaux régional et local, permettent de modifier fortement les scénarios de l origine de la biodiversité en Nouvelle-Calédonie. Loin d être une relique purement Gondwanienne et une région dont la diversification a été progressive et ancienne ( Modèle Muséum ), la Nouvelle-Calédonie montre les caractéristiques nuancées de toutes les faunes tropicales, avec plusieurs strates de peuplement et une combinaison d événements anciens et récents. Ce scénario se révèle être aussi plus cohérent avec l histoire géologique mouvementée de la Nouvelle-Calédonie, notamment la submersion totale du territoire.PARIS-BIUSJ-Thèses (751052125) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

Integrative taxonomy of the genus Dyscolus (Coleoptera, Carabidae, Platynini) in Ecuadorian Andes

International audienceThe genus Dyscolus Dejean, 1831 is a highly speciose taxon of neotropical Carabidae and the major component of high-altitude ground beetle communities in the tropical Andes. The aim of this study is threefold: (i) refine the taxonomic position of the equatorial members of Dyscolus using molecular data, (ii) provide a delimitation of the species found in Ecuador in páramo and montane forest environments based on a robust combination of molecular and morphological data, (iii) describe the new species and take the nomenclatural decisions made necessary by the results of this study. The seclusion of Dyscolus from more basal platynine clades including Platynus, Batenus and Glyptolenus, is supported by a phylogenetic analysis of the COI marker. Twenty-five new species of Dyscolus, most of them microendemic, are described and illustrated: D. aquator Moret sp. nov. (Tandayapa, Pichincha), D. arauzae Moret sp. nov. (Mt Cayambe, Pichincha), D. arborarius Moret sp. nov. (Parque Nacional Yacuri, Loja), D. barragani Moret sp. nov. (Mt Ayapungu, Chimborazo), D. crespoae Moret sp. nov. (Parque Nacional Podocarpus, Zamora-Chinchipe), D. danglesi Moret sp. nov. (Parque Nacional Yacuri, Loja), D. donosoi Moret sp. nov. (Parque Nacional Podocarpus, Zamora-Chinchipe), D. eleonorae Moret sp. nov. (Cotopaxi and Pichincha provinces), D. famelicus Moret sp. nov. (Papallacta, Napo), D. giselae Moret sp. nov. (Reserva Otonga, Cotopaxi), D. globoculus Moret sp. nov. (Parque Nacional Podocarpus, Zamora-Chinchipe), D. gobbii Moret sp. nov. (Guamaní and Mt Antisana, Pichincha), D. incommunis Moret sp. nov. (Tandayapa, Pichincha), D. marini Moret sp. nov. (Parque Nacional Podocarpus, Loja), D. piscator Moret sp. nov. (Guamaní, Napo), D. placitus Moret sp. nov. (Guamaní, Napo), D. ravidus Moret sp. nov. (Parque Nacional Podocarpus, Loja), D. rivinus Moret sp. nov. (Reserva Otonga, Cotopaxi), D. rugitarsis Moret sp. nov. (Parque Nacional Yacuri, Loja), D. ruizi Moret sp. nov. (Parque Nacional Podocarpus, Loja and Zamora), D. salazarae Moret sp. nov. (Parque Nacional Podocarpus, Loja), D. silvestris Moret sp. nov. (Papallacta, Napo), D. sulcipedis Moret sp. nov. (Parque Nacional Yacuri, Loja), D. verecundior Moret sp. nov. (Mt Illiniza and Mt Corazón, Pichincha) and D. verecundissimus Moret sp. nov. (Mt Chimborazo, Chimborazo). Dyscolus palatus Moret, 1998 is newly synonymized with D. denigratus (Bates, 1891). We demonstrate the subgenus Hydrodyscolus Moret, 1996 to be polyphyletic and therefore consider it a junior synonym of Dyscolus Dejean, 1831

Origine de la biodiversité en Nouvelle-Calédonie (analyse phylogénétique de l'endémisme chez les insectes dictyoptères)

Dans le but d analyser l origine de l endémisme en Nouvelle-Calédonie, l histoire évolutive des Insectes Blattidae (Hexapodes, Dictyoptères) a été reconstruite au niveau moléculaire par l application de différentes méthodes phylogénétiques. Les différents résultats obtenus, aux niveaux régional et local, permettent de modifier fortement les scénarios de l origine de la biodiversité en Nouvelle-Calédonie. Loin d être une relique purement Gondwanienne et une région dont la diversification a été progressive et ancienne ( Modèle Muséum ), la Nouvelle-Calédonie montre les caractéristiques nuancées de toutes les faunes tropicales, avec plusieurs strates de peuplement et une combinaison d événements anciens et récents. Ce scénario se révèle être aussi plus cohérent avec l histoire géologique mouvementée de la Nouvelle-Calédonie, notamment la submersion totale du territoire.PARIS-BIUSJ-Thèses (751052125) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

Integrative taxonomy of the genus &lt;I&gt;Dyscolus&lt;/I&gt; (Coleoptera, Carabidae, Platynini) in Ecuadorian Andes

The genus Dyscolus Dejean, 1831 is a highly speciose taxon of neotropical Carabidae and the major component of high-altitude ground beetle communities in the tropical Andes. The aim of this study is threefold: (i) refine the taxonomic position of the equatorial members of Dyscolus using molecular data, (ii) provide a delimitation of the species found in Ecuador in páramo and montane forest environments based on a robust combination of molecular and morphological data, (iii) describe the new species and take the nomenclatural decisions made necessary by the results of this study. The seclusion of Dyscolus from more basal platynine clades including Platynus, Batenus and Glyptolenus, is supported by a phylogenetic analysis of the COI marker. Twenty-five new species of Dyscolus, most of them microendemic, are described and illustrated: D. aquator Moret sp. nov. (Tandayapa, Pichincha), D. arauzae Moret sp. nov. (Mt Cayambe, Pichincha), D. arborarius Moret sp. nov. (Parque Nacional Yacuri, Loja), D. barragani Moret sp. nov. (Mt Ayapungu, Chimborazo), D. crespoae Moret sp. nov. (Parque Nacional Podocarpus, Zamora-Chinchipe), D. danglesi Moret sp. nov. (Parque Nacional Yacuri, Loja), D. donosoi Moret sp. nov. (Parque Nacional Podocarpus, Zamora-Chinchipe), D. eleonorae Moret sp. nov. (Cotopaxi and Pichincha provinces), D. famelicus Moret sp. nov. (Papallacta, Napo), D. giselae Moret sp. nov. (Reserva Otonga, Cotopaxi), D. globoculus Moret sp. nov. (Parque Nacional Podocarpus, Zamora-Chinchipe), D. gobbii Moret sp. nov. (Guamaní and Mt Antisana, Pichincha), D. incommunis Moret sp. nov. (Tandayapa, Pichincha), D. marini Moret sp. nov. (Parque Nacional Podocarpus, Loja), D. piscator Moret sp. nov. (Guamaní, Napo), D. placitus Moret sp. nov. (Guamaní, Napo), D. ravidus Moret sp. nov. (Parque Nacional Podocarpus, Loja), D. rivinus Moret sp. nov. (Reserva Otonga, Cotopaxi), D. rugitarsis Moret sp. nov. (Parque Nacional Yacuri, Loja), D. ruizi Moret sp. nov. (Parque Nacional Podocarpus, Loja and Zamora), D. salazarae Moret sp. nov. (Parque Nacional Podocarpus, Loja), D. silvestris Moret sp. nov. (Papallacta, Napo), D. sulcipedis Moret sp. nov. (Parque Nacional Yacuri, Loja), D. verecundior Moret sp. nov. (Mt Illiniza and Mt Corazón, Pichincha) and D. verecundissimus Moret sp. nov. (Mt Chimborazo, Chimborazo). Dyscolus palatus Moret, 1998 is newly synonymized with D. denigratus (Bates, 1891). We demonstrate the subgenus Hydrodyscolus Moret, 1996 to be polyphyletic and therefore consider it a junior synonym of Dyscolus Dejean, 1831.</p

On the presence of the giant freshwater prawn, Macrobrachium rosenbergii, in French Guiana confirmed by citizen science and genetic analyses

We report for the first time the presence of self-sustaining populations of Macrobrachium rosenbergii in French Guiana. Genetic analyses of the cytochrome c oxidase subunit I marker (COI) confirmed the identity of the species as well as historical records about the introduction of the species from commercial stocks. Despite the limited presence of Macrobrachium rosenbergii in French Guiana, the species is recorded in several river basins, including two where the species has never been farmed. This suggests that the species is able to disperse locally and highlights its potential invasive nature in the territory

Explosive Evolution of an Ancient Group of Cyphophthalmi (Arachnida: Opiliones) in the Balkan Peninsula

Aim: To investigate the phylogeny of the genus Cyphophthalmus in the Balkan Peninsula and to test the current recognition of ‘phyletic lines’ and phylogenetic groups proposed in previous studies in order to elucidate the biogeographical history of the region. Location: Europe, Balkan Peninsula, Adria microplate. Methods: Two mitochondrial (cytochrome c oxidase subunit I and 16S rRNA) and two nuclear (28S rRNA and 18S rRNA) markers were used to infer the phylogenetic history of the group. Molecular dating with relaxed molecular clocks was used to elucidate the relative time of diversification within the genus Cyphophthalmus and its constituent lineages. Results: Our analyses confirm the monophyly of the genus Cyphophthalmus, and that of the Aegean and gjorgjevici lineages, whereas the ‘Dinaric lineage’ appears paraphyletic. Main conclusions: We show that the genus Cyphophthalmus is an old endemic from the Balkan biogeographical region, which gave origin to at least three main lineages. Those lineages have diversified within overlapping ranges. According to our molecular dating, they have also diversified within the same timeframe. The Dinaric Alps, although presenting a large number of species, cannot be inferred as the centre of origin of the group. Instead, the biogeographical evolution of the genus could be related to the palaeogeographic history of the Adria microplate.Organismic and Evolutionary Biolog

Comparative phylogeography of the centipedes Cryptops pictus and C. niuensis (Chilopoda) in New Caledonia, Fiji and Vanuatu

The South Pacific is a biodiverse region of extreme evolutionary importance because it harbors ancient lineages and recent radiations. However, few population-level studies of genetic variation have been conducted in the land masses of this region. Likewise, the number of population-level studies using myriapods as models is extremely small. In this article, we compare the genetic structure of two species of centipedes in the genus Cryptops endemic to the South Pacific, one from a continental island, the other from oceanic islands. The level of genetic diversity and structure in C. pictus, a species endemic to New Caledonia, is much higher than in C. niuensis in Fiji and Vanuatu, despite the fact that C. niuensis is spread across two different archipelagos and several islands. The most likely explanation is the relatively young age of the remnants of the Vitiaz Arc (Fiji and Vanuatu) compared to New Caledonia. Using the emergence of Fiji-Vanuatu as a calibration point, C. pictus is estimated to have diverged by 23.4 Mya (upper 95% confidence interval) with a mean estimate of 11.7 Mya versus the 9.7 Mya of C. niuensis. Considering the absence of shared sequences between specimens from different sampling sites and the high genetic structuring within populations, C. pictus appears to be an ideal candidate to assess historical processes at a micro-evolutionary scale in New Caledonia.Organismic and Evolutionary Biolog

Online database for mosquito (Diptera, Culicidae) occurrence records in French Guiana

International audienceA database providing information on mosquito specimens (Arthropoda: Diptera: Culicidae) collected in French Guiana is presented. Field collections were initiated in 2013 under the auspices of the CEnter for the study of Biodiversity in Amazonia (CEBA: http://www.labexceba.fr/en/). This study is part of an ongoing process aiming to understand the distribution of mosquitoes, including vector species, across French Guiana. Occurrences are recorded after each collecting trip in a database managed by the laboratory Evolution et Diversité Biologique (EDB), Toulouse, France. The dataset is updated monthly and is available online. Voucher specimens and their associated DNA are stored at the laboratory Ecologie des Forêts de Guyane (Ecofog), Kourou, French Guiana. The latest version of the dataset is accessible through EDB's Integrated Publication Toolkit at http://130.120.204.55:8080/ipt/resource.do?r=mosquitoes_of_ french_guiana or through the Global Biodiversity Information Facility data portal at http://www.gbif.org/ dataset/5a8aa2ad-261c-4f61-a98e-26dd752fe1c5 It can also be viewed through the Guyanensis platform at http://guyanensis.ups-tlse.f