Browsing by Author "Doadrio, Ignacio"
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- Broad-scale sampling of primary freshwater fish populations reveals the role of intrinsic traits, inter-basin connectivity, drainage area and latitude on shaping contemporary patterns of genetic diversityPublication . Santos, Carla Sousa; Robalo, Joana Isabel; Pereira, Ana Martins; Branco, Paulo; Santos, José Maria; Ferreira, Maria Teresa; Sousa, Mónica; Doadrio, IgnacioBackground. Worldwide predictions suggest that up to 75% of the freshwater fish species occurring in rivers with reduced discharge could be extinct by 2070 due to the combined effect of climate change and water abstraction. The Mediterranean region is considered to be a hotspot of freshwater fish diversity but also one of the regions where the effects of climate change will be more severe. Iberian cyprinids are currently highly endangered, with over 68% of the species raising some level of conservation concern. Methods. During the FISHATLAS project, the Portuguese hydrographical network was extensively covered (all the 34 river basins and 47 sub-basins) in order to contribute with valuable data on the genetic diversity distribution patterns of native cyprinid species. A total of 188 populations belonging to 16 cyprinid species of Squalius, Luciobarbus, Achondrostoma, Iberochondrostoma, Anaecypris and Pseudochondrostoma were characterized, for a total of 3,678 cytochrome b gene sequences. Results. When the genetic diversity of these populations was mapped, it highlighted differences among populations from the same species and between species with identical distribution areas. Factors shaping the contemporary patterns of genetic diversity were explored and the results revealed the role of latitude, inter-basin connectivity, migratory behaviour, species maximum size, species range and other species intrinsic traits in determining the genetic diversity of sampled populations. Contrastingly, drainage area and hydrological regime (permanent vs. temporary) seem to have no significant effect on genetic diversity. Species intrinsic traits, maximum size attained, inter-basin connectivity and latitude explained over 30% of the haplotype diversity variance and, generally, the levels of diversity were significantly higher for smaller sized species, from connected and southerly river basins. Discussion. Targeting multiple co-distributed species of primary freshwater fish allowed us to assess the relative role of historical versus contemporary factors affecting genetic diversity. Since different patterns were detected for species with identical distribution areas we postulate that contemporary determinants of genetic diversity (species' intrinsic traits and landscape features) must have played a more significant role than historical factors. Implications for conservation in a context of climate change and highly disturbed habitats are detailed, namely the need to focus management and conservation actions on intraspecific genetic data and to frequently conduct combined genetic and demographic surveys.
- Chondrostoma oligolepis, new replacement name for Leuciscus macrolepidotus Steindachner, 1866 (Teleostei: Cyprinidae)Publication . Robalo, Joana Isabel; Doadrio, Ignacio; Almada, Vítor Carvalho; Kottelat, MauriceInexistente
- Descripción de dos especies nuevas del género Squalius Bonaparte, 1837 (Actinopterygii, Leuciscidae) en la Península IbéricaPublication . Doadrio, Ignacio; Sousa-Santos, Carla; Perea, SilviaTwo new species, Squalius gaditanus sp. nov. and Squalius tartessicus sp. nov. are described on the basis of morphological and genetic traits. Squalius gaditanus is restricted to the Barbate, Jara and Miel drainages in the province of Cádiz (Southern Spain). Squalius gaditanus sp. nov. can be distinguished from other Squalius species from the Iberian Peninsula through a combination of morphometric, meristic and genetic characters: 36-40 (χ = 38) pored scales on the lateral line; 6-7 (χ = 6.7) scales above the lateral line; 2-3 (χ = 2.8) scales below the lateral line; vertebrae 37-39 (χ = 38); second infraorbital bone narrower than the third in adults; maxilla with reduced pointed anterior process; posterior process of the maxilla long and thin; lower branch of the pharyngeal bone short and robust; pharyngeal plate of basioccipital rounded and two autapomorphies in the mitochondrial cytochrome b gene. Squalius tartessicus sp. nov. inhabits the Almargem, Gilão, Odiel, Guadiana, Guadalquivir, Guadalete, Guadalhorce, Velez, Guadalfeo and Segura drainages in the southern part of the Iberian Peninsula. Squalius tartessicus sp. nov. can be differentiated from other Squalius species from the Iberian Peninsula through a set of morphometric, meristic and genetic traits: 37-41(χ = 38.8) pored scales on the lateral line; 6-7 (χ = 7) scales above the lateral line; 2-3 (χ = 2.9) scales below the lateral line; 37-39 (χ = 38) number of vertebrae; infraorbital bones unusually wide in adults; maxilla with discernable pointed anterior process; posterior process of the maxilla long and thin; lower branch of the pharyngeal bone short and robust; pharyngeal plate of basioccipital triangular in shape; posterior lamina of cleithrum expanding posteriorly.
- Different stocks of brook lamprey in Spain and their origin from Lampetra fluviatilis at two distinct times and placesPublication . Pereira, Ana Martins; Doadrio, Ignacio; Robalo, Joana Isabel; Almada, Vítor CarvalhoUsing the mitochondrial non-coding region I, it was shown that the two Spanish Lampetra planeri populations (Cares–Deva and Olabidea–Ugarana) correspond to different genetic units. The Cares–Deva population is probably a recent offshoot of Lampetra fluviatilis, being the Olabidea–Ugarana population less diverse and of older origin.
- Genetic relationships of brook lamprey of the genus Lampetra in a Pyrenean stream in SpainPublication . Pereira, Ana Martins; Almada, Vítor Carvalho; Doadrio, IgnacioThe genetic relationships of a population of brook lamprey Lampetra planeri from Spain were analysed using a fragment of the mitochondrial non-coding region in order to describe its relationships with other European Lampetra populations. DNA sequences were obtained from ten larvae, all corresponding to a single private haplotype. Its closest haplotype differed by five mutations and was found in several samples of Lampetra fluviatlis, both from the North Sea and the Baltic. These results argue for the great conservation value of this brook lamprey population, likely originated from L. fluviatilis ancestors.
- Historical biogeography of european leuciscins (Cyprinidae): Evaluating the Lago Mare dispersal hypothesisPublication . Levy, André; Doadrio, Ignacio; Almada, Vítor CarvalhoABSTRACT Aim To test the importance of the Lago Mare stage of the Messinian Salinity Crisis for the dispersal and diversification of European leuciscins (Cyprinidae: Leuciscinae). Location Europe. Methods Cytochrome b sequences of European leuciscins were employed to investigate phylogenetic relationships among species, using Bayesian inference, and to estimate times of diversification, using a relaxed molecular clock. The distributions of 190 European leuciscins were compiled, and regional species compositions were compared using a taxonomic similarity index and an area cladogram. Results Leuciscins restricted to the Iberian and Italian peninsulas and the West and South Balkan regions are phylogenetically more closely related to northern European species than to species from another southern European area. Application of a relaxed molecular clock to a Bayesian phylogeny indicates that most southern clades originated and diversified prior to the Messinian. Southern European regions are taxonomically distinct from one another, and from a more taxonomically homogeneous group of areas that includes Anatolia, East Balkans, Middle East, North Europe and West Russia. Main conclusions The scenario of a Messinian period of dispersal of Paratethyan fauna into Mediterranean regions, via the Lago Mare, predicts a rapid period of diversification and a pattern of close association among southern European faunas. Phylogenetic relationships among leuciscins, the timing of cladogenic events, and the taxonomic similarity among geographical regions do not conform to this expectation. The depth of clades endemic to southern Europe, together with the high levels of endemism in these regions, suggests that the faunas in these regions diverged prior to the Messinian and have evolved largely in isolation from one another. Our results support a model of gradual colonization of Mediterranean regions since the Oligocene. Subsequent connections between adjacent areas may have occurred in the Messinian or Pleistocene.
- Historical biogeography of the Iberian Peninsula: multilocus phylogeny and ancestral area reconstruction for the freshwater fish genus Squalius (Actinopterygii, Leuciscidae)Publication . Perea, Silvia; Sousa‐Santos, Carla; Robalo, Joana; Doadrio, IgnacioThe Iberian Peninsula is one of the most ancient geological areas in Europe. Its complex orography is a consequence of several geological episodes related with two orogenic episodes that occurred from Late Devonian (Variscan orogeny) to the Cenozoic (Alpine orogeny). Unraveling the evolutionary history of strict freshwater fauna, such as leuciscid fishes, may contribute to our understanding of the paleogeographic history of a region and its configuration along time. Within the Iberian freshwater fish fauna, the genus Squalius is one of the oldest and most diversified leuciscids. Here, we used phylogenetic, phylogeographic, and ancestral area reconstruction approaches to infer relationships among Iberian drainages and the biogeographic history of these Squalius species, particularly of two of the most widely distributed species, S. carolitertii and S. pyrenaicus. Our results confirmed, in agreement with previous studies, an underestimation of the real diversity of Squalius in the Iberian Peninsula and identified divergent evolutionary lineages, highlighting the reticulate evolutionary history of the Iberian Squalius species. The ancestral reconstruction analyses indicated that several vicariance and dispersal processes occurred among different Squalius lineages, linked to the paleogeographic configuration of the Iberian Peninsula during the Cenozoic period.
- Identification of ESUs in the critically endangered portuguese minnow Chondrostoma lusitanicum Collares-Pereira 1980, based on a phylogeographical analysisPublication . Robalo, Joana Isabel; Doadrio, Ignacio; Valente, Alexandre; Almada, Vítor CarvalhoIn this paper, we analysed the phylogeography of the Critically Endangered fish Chondrostoma lusitanicum (Cyprinidae) endemic to Portugal. A fragment of the mitochondrial cyt b gene and one from the nuclear beta-actin gene were sequenced. The results support recognition of 3 ESU’s distributed as follows: 1) Sado River, 2) the Tagus River basin and 3 independent nearby coastal rivers (collectively named ‘‘West’’) and 3) Lagoa de Albufeira, a small coastal lagoon between Tagus and Sado basins.
- Insights on speciation patterns in the genus Iberochondrostoma (Cyprinidae): Evidence from mitochondrial and nuclear dataPublication . Robalo, Joana Isabel; Doadrio, Ignacio; Valente, Alexandre; Almada, Vítor CarvalhoIn this paper, the patterns of cladogenesis in the cyprinid fish genus Iberochondrostoma were analysed using a mitochondrial (cytochrome b) and a nuclear (beta-actin) gene fragment. The two genes yielded discordant results. While the cytochrome b gene yielded a fully dichotomous tree, where all species of the genus are monophyletic, the much slower beta-actin gene yielded star-like relationships. However, when information from both genes was considered together, the data suggested the persistence of a very large central unit from which at least two peripheral clades arose at different times. This pattern which is akin to peripatric speciation was shown to be compatible with the paleogeographical information available. It is suggested that combining the techniques of phylogeny and phylogeography and the use of multiple markers varying in their rate of evolution may enrich our understanding of speciation and evolution of clades beyond species level.
- Metapopulations in temporary streams - The role of drought-flood cycles in promoting high genetic diversity in a critically endangered freshwater fish and its consequences for the futurePublication . Santos, Carla Sousa; Robalo, Joana Isabel; Francisco, Sara Martins; Carrapato, Carlos; Cardoso, Ana Cristina; Doadrio, IgnacioGenetic factors have direct and indirect impacts in the viability of endangered species. Assessing their genetic diversity levels and population structure is thus fundamental for conservation and management. In this paper we use mitochondria] and nuclear markers to address phylogeographic and demographic data on the critically endangered Anaecypris hispanica, using a broad sampling set which covered its known distribution area in the Iberian Peninsula. Our results showed that the populations of A. hispanica are strongly differentiated (high and significant Phi(ST) and F-ST values, corroborated by the results from AMOVA and SAMOVA) and genetically diversified. We suggest that the restricted gene flow between populations may have been potentiated by ecological, hydrological and anthropogenic causes. Bayesian skyline plots revealed a signal for expansion for all populations (t(MRCA) between 68 kya and 1.33 Mya) and a genetic diversity latitudinal gradient was detected between the populations from the Upper (more diversified) and the Lower (less diversified) Guadiana river basin. We postulate a Pleistocenic westwards colonization route for A. hispanica in the Guadiana river basin, which is in agreement with the tempo and mode of paleoevolution of this drainage. The colonization of River Guadalquivir around 60 kya with migrants from the Upper Guadiana, most likely by stream capture, is also suggested. This study highlights the view that critically endangered species facing range retreats (about 47% of its known populations have disappeared in the last 15 years) are not necessarily small and genetically depleted. However, the extinction risk is not negligible since A. hispanica faces the combined effect of several deterministic and stochastic negative factors and, moreover, recolonization events after localized extinctions are very unlikely to occur due to the strong isolation of populations and to the patchily ecologically-conditioned distribution of fish. The inferred species distribution models highlight the significant contribution of temperature seasonality and isothermality to A. hispanica occurrence in Guadiana environments and emphasize the importance of stable climatic conditions for the preservation of this species. Given the strong population structure, high percentage of private haplotypes and virtual absence of inter-basin gene flow we suggest that each A. hispanica population should be considered as an independent Operational Conservation Unit and that ex-situ and in-situ actions should be conducted in parallel to allow for the long-term survival of the species and the preservation of the genetic integrity of its populations. (C) 2014 Elsevier Inc. All rights reserved.
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