Phylogeography of Eleotris fusca (Teleostei: Gobioidei: Eleotridae) in the Indo-Pacific area reveals a cryptic species in the Indian Ocean

International audienceIndo-Pacific insular freshwater systems are mainly dominated by amphidromous species. Eleotris fusca is a widespread one, its life cycle is characterised by a marine pelagic larval phase allowing the species to disperse in the ocean and then to recruit to remote island rivers. In the present study, the population structure of E. fusca over its Indo-Pacific distribution range (Western Indian Ocean to French Polynesia, Pacific Ocean) was evaluated. We analysed a section of mitochondrial COI of 557 individuals sampled from 28 islands to visualise the population structure. Haplotypes diversity (Hd) was between 0.458 and 1 and, nucleotide diversity (π) was between 0.001 and 0.02. Two distinct genetic groups appeared, one in the Indian Ocean and the other in the Pacific Ocean (FST mean = 0.901; 5.2% average divergence). Given these results, complete mitogenomes (mtDNA) were sequenced and combined with the nuclear Rhodopsin (Rh) gene for a subset of individuals. The two phylogenetic trees based on each analysis showed the same genetic pattern: two different groups belonging to the Indian and the Pacific oceans (6.6 and 1.6% of divergence for mtDNA and Rh gene respectively), which supported species level differentiation. These analyses revealed the presence of two sister species confounded until present under the name of Eleotris fusca. One of them is cryptic and endemic of the Indian Ocean and the other one is the true E. fusca, which keeps, nevertheless, its status of widespread species

Molecular systematics and biogeography of the Hemigalinae civets (Mammalia, Carnivora)

Due to the difficulty in obtaining samples, the systematics of the Hemigalinae civets has not been fully resolved. The aim of this study was to clarify the relationships of the species and the intraspecific diversity within this subfamily, and to explore the environmental factors that might have affected its evolution. Using two mitochondrial and two nuclear markers, we confirmed that the Hemigalinae comprises Owston’s civet, the otter civet, Hose’s civet and the banded civet, but also the Sulawesi palm civet (formerly included in the Paradoxurinae). Our study showed that the banded and Owston’s civets are sister species, and suggested that Hose’s civet is sister to these two. Within the banded civet, we observed a high divergence between individuals from the Mentawai Islands and those from Sumatra and Borneo (while the latter two were not strongly divergent), likely due to the deep sea channel between the Mentawai Islands and Sumatra. Unexpectedly, the Sumatran and Peninsular Malaysian individuals were not closely related, despite the fact that these two regions have repeatedly been connected during the last glaciations. No high polymorphism was found within Owston’s civet, although three groups were obtained: southern China, northern Vietnam and central Vietnam, which might be related to Pleistocene climatic fluctuations

Does your lip stick? Evolutionary aspects of the mouth morphology of the Indo‐Pacific clinging goby of the Sicyopterus genus (Teleostei: Gobioidei: Sicydiinae) based on mitogenome phylogeny

International audienc

Data from: The complex phylogeography of the Indo-Malayan Alophoixus bulbuls with the description of a putative new ring species complex

The Indo-Malayan bioregion has provided some of the most spectacular discoveries of new vertebrate species (e.g. saola, khanyou, bare-faced bulbul) over the last 25 years. Yet, very little is known about the processes that led to the current biodiversity in this region. We reconstructed the phylogeographic history of a group of closely related passerines, the Alophoixus bulbuls. These birds are continuously distributed in Indo-Malaya around the Thailand lowlands such that their distribution resembles a ring. Our analyses revealed a single colonization event of the mainland from Sundaland with sequential divergence of taxa from southwest to northeast characterized by significant gene flow between parapatric taxa, and reduced or ancient gene flow involving the two taxa at the extremities of the ring. We detected evidence of population expansion in two subspecies, including one that was involved in the closing of the ring. Hence, our analyses indicate that the diversification pattern of Alophoixus bulbuls fits a ring species model driven by geographic isolation. To our knowledge, the Alophoixus bulbuls represent the first case of a putative broken ring species complex in Indo-Malaya. We also discuss the implications of our results on our understanding of the biogeography in Indo-Malaya

Input files for the different analyses

The compressed folder includes the input files used for the following analyses: a) gene trees, b) species tree, c) Structure, d) Isolation with migration model analyses, e) the phased sequence data for all loci and f) a spreadsheet to make the link between the acronyms used in the analyses input files and the Tissue number/localities/subspecie

The Antarctic fish genus Artedidraco is paraphyletic (Teleostei, Notothenioidei, Artedidraconidae)

Artedidraconids (Plunderfishes) are small benthic notothenioid fishes of the Antarctic and South Georgia shelf and slope. The family Artedidraconidae is monophyletic; however, the relationships within the family have remained poorly explored until now, and based on a small sample of the genus Artedidraco. The present study focuses on the interrelationships among the artedidraconid genera and the phylogeny of the genus Artedidraco. 2,353 base pairs from 77 specimens were sequenced from the partial mitochondrial cytochrome oxidase I gene and cytochrome b gene, the partial mitochondrial control region and the partial nuclear rhodopsin retrogene. The genus Artedidraco is not monophyletic, confirming the preliminary relationships found by Derome et al. (Mol Phylogenet Evol 24:139–152, 2002): Pogonophryne, Dolloidraco and Histiodraco are well embedded within the genus Artedidraco. From Artedidraco skottsbergi and A. loennbergi to A. orianae and A. mirus, the tree shows that there is an increasing number of upper lateral line tubular scales and decreasing number of disc-shaped scales. There is also a trend toward a decrease in the number of epipleural ribs and an increase in number of pleural ribs along the tree

Feeding ecology of two deep-sea skates bycaught on demersal longlines off Kerguelen Islands, Southern Indian Ocean

International audienceElasmobranchs, and particularly skates (Rajiforms), are commonly caught in fisheries worldwide as targeted catch or bycatch. Their life history traits make them particularly sensitive to elevated fishing mortality, especially in slow-growing deep-sea species. Knowledge of their ecology is key to ensure effective conservation and mitigation measures, especially dietary references to understand trophic relationships within the ecosystem. This study presents the first comprehensive description of diet composition and trophic position of two skate species (Bathyraja eatonii and B. irrasa) caught as bycatch in the French Patagonian toothfish (Dissostichus eleginoides) fishery in the Indian sector of the Southern Ocean (Kerguelen waters). Stomach content and stable isotopic analyses were performed on both species according to sex and maturity stage. DNA barcoding analysis was performed on prey tissue samples to identify or confirm identification of prey items found in stomachs. Overall, both skate species were generalist feeders with high δ15N values. The higher δ15N values of B. irrasa result in a higher estimated trophic position than B. eatonii. The diet of B. eatonii mainly consisted of fish, pelagic crustaceans and squids, while B. irrasa preyed more on benthic crustaceans, fish and annelids. While sex had no effect on diet and trophic position for both species, maturity stage influenced the prey composition of B. irrasa. Annelids and isopods were prevalent in the stomachs of immature individuals of B. irrasa, while mature individuals fed more on decapods and fish. Our results revealed a wide range of prey items for these two generalist predators (>57 species). Understanding the diet, trophic position and trophic relationships of B. eatonii and B. irrasa is critical to a better comprehension of the impact of the exploitation of top predators on the subantarctic demersal ecosystem

Trematominae and Artedidraconinae: contrasted mitogenome evolution for two Antarctic radiations

Cellular respiration has been widely studied in Antarctic teleost fishes because of their peculiar adaptations to an extreme environment. In parallel mitochondrial sequence markers have become highly popular for molecular systematics. However, there are few whole mitochondrial genome sequences published, and none available for some of the subfamilies. Here, we present two large mitogenome datasets including most species and multiple sequences for many species of two subfamilies, Trematominae and Artedidraconinae (Duhamel et al. 2014). These include two highly diverse but very different adaptative radiations, with contrasting divergence dates, morphological polymorphism, and habitat dominance. The sampling is based on a well identified, extensive collection resulting from the 2008 CEAMARC survey and the subsequent REVOLTA surveys in Terre Adélie (IPEV), already DNA barcoded and sequenced in previous studies. The mitogenome sequences for these two subfamilies differ in composition, gene order, and relative divergence of mitochondrial markers, with strong, taxon-specific biases like very high C contents in some regions. The gene order change provides a synapomorphy for the subfamily Trematominae and an interesting development in teleost mitogenomes. The complete Artedidraconinae mitogenomes provide a much higher amount of variable sites (approx*30), while previous sequence datasets were plagued by low informativeness (Lecointre et al. 2011). As already established on single mitochondrial genes, intraspecific variability is lower than interspecific variability within each subfamily, however interspecific variability in Artedidraconinae is lower or similar to intraspecific variability in Trematominae. This expanded dataset confirms the unusual evolution of the mitochondrial coded sequences involved in the cellular respiration in Antarctic Nototheniidae, as well as the usefulness of complete mitochondrial genomes for their systematics. The two level multiplexing (Timmermans et al. 2010) and next generation sequencing of long PCR amplicons (following Hinsinger et al. 2015) is efficient to obtain large mitogenomic datasets representative of both inter- and intraspecific variability, key to the understanding of mitochondrial evolution and a step closer to resolving the relationships among these taxa.RECTO (Refugia and Ecosystem Tolerance in the Southern Ocean, BR/154/A1/RECTO