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- Origin and history of Phoxinus (Cyprinidae) introductions in the Douro Basin (Iberian Peninsula): an update inferred from genetic dataPublication . Garcia-Raventós, Aina; Martins, Filipa M.S.; Teixeira, Amílcar; Sousa, Ronaldo; Froufe, Elsa; Varandas, Simone; Lopes-Lima, Manuel; Beja, Pedro; Filipe, Ana FilipaThe number of non-native freshwater fishes in the Iberian Peninsula has been greatly increasing. In this study, individuals of the genus Phoxinus were detected in 18 out of 138 stream sites sampled across the Douro Basin in 2017 and 2018. A total of 26 individuals were barcoded using partial cytochrome c oxidase subunit I (COI) and cytochrome b (cytb) genes for species identification and determination of geographical origin. Molecular data provided the first record of a second Phoxinus species in western Douro (Portugal, Iberian Peninsula), with haplotypes closely matching those found in the Charente River (southern France). This species is suspected to be a recent introduction associated with the use of minnows as live bait by freshwater anglers, which was facilitated by human movements between France and Portugal. Individuals from watercourses in eastern Douro (Spain) were genetically assigned to Phoxinus bigerri, an introduced species previously known for that region, which confirms reports of introduction events from Ebro to Douro Basin probably also related to freshwater angling and facilitated by geographic proximity. The potential ecological impacts of this genus in the region are unknown and need further investigation.
- Phylogeny of European Anodontini (Bivalvia: Unionidae) with a redescription of Anodonta exulcerataPublication . Riccardi, Nicoletta; Froufe, Elsa; Bogan, Arthur E.; Zieritz, Alexandra; Teixeira, Amílcar; Vanetti, Isabella; Varandas, Simone; Zaccara, Serena; Nagel, Karl Otto; Lopes-Lima, ManuelFreshwater bivalves are highly threatened and globally declining due to multiple anthropogenic impacts, making them important conservation targets. Because conservation policies and actions generally occur at the species level, accurate species identification and delimitation is critical. A recent phylogenetic study of Italian mussel populations revalidated an Anodonta species bringing the number of known European Anodontini from three to four species. The current study contributes to the clarification of the taxonomy and systematics of European Anodontini, using a combination of molecular, morphological and anatomical data, and constructs phylogenies based on complete mitogenomes. A redescription of A. exulcerata and a comparative analysis of morphological and anatomical characters with respect to the other two species of Anodonta present in the area are provided. No reliable diagnostic character has emerged from comparative analysis of the morphometric characters of 109 specimens from 16 sites across the Italian peninsula. In fact, the discriminant analysis resulted in a greater probability of correct assignment to the site of origin than to the species. This confirms the difficulties of an uncritical application of visual characters for the delimitation of species, especially for Anodontinae.
- Freshwater mussels in Italy: from no-name species and no-right species to useless regulationPublication . Riccardi, Nicoletta; Froufe, Elsa; Teixeira, Amílcar; Varandas, Simone; Moro, Giuseppe; Lopes-Lima, ManuelAny conservation management plan requires at the veiy least the following information: (l) clearly defined target species, and data on the species' (2) distribution and (3) population size. For European freshwater mussels this information is missing, deficient or outdated, and unevenly distributed among the different European countries. Paradoxically, the Southem European countries, more vulnerable to the impacts of climate change and water shortage, are those more poorly studied. Despite being recognized as a center of endemism and one of the major refugia of the glacial ages for several taxa, Italy is no exception. Information deficiencies result, at least in part, from objective difficulties, ex. taxonomic uncertainties and misidentifications. Thcsc latter affect both the legislation and the aUocation offunds, which are stricüy interdependent. Two Italian examples will be used to illustrate a paradox that practically hinders both the acquisition of information and, a fortiori, possible conservation actions: l) a "new" species that will not be included in the inventory or protected until the legislative bureaucratic procedure hás taken its course; 2) an "old" species that will become exünct without any conservation plan, because it appears only in the Annex V of the European Directive. Unfortunately, these two examples represent only the tip of the iceberg; underneath there are many legislative inconsistencies that contribute to forming a "cultural threat". A scaling up from the Italian to the European levei shows a further "threat": triggered by funding limitations, the growing spread of data-sharing infrastructures amplifies "errors" (e. g. mis-identifications). Like in avicious circle, species are going lost whüe the few resources still avaüable are absorbed to "capitalize" on already existing, mostly inadequate, knowledge.
- Multiple introductions and first record of Phoxinus phoxinus in the Douro Basin revealed by molecular dataPublication . Garcia-Raventós, Aina; Martins, Filipa; Magalhães, Maria Filomena; Ramião, José; Ferreira, Mário; Carona, Sara; Carvalho, Francisco; Sousa, Ronaldo; Froufe, Elsa; Teixeira, Amílcar; Varandas, Simone; Lopes-Lima, Manuel; Beja, Pedro; Filipe, Ana FilipaBiological invasions are a major threat to global biodiversity. Freshwater ecosystems are particularly vulnerable to anthropogenic introductions. This is the case of the minnows (Phoxinus genus), which have been used as a live bait since the 1900s. Until recently, Phoxinus phoxinus was thought to be distributed across most of the European watercourses, including the Iberian Peninsula (Ebro Basin and Cantabrian region). In 2007, these Iberian populations were identified as Phoxinus bigerri, including the traslocated populations in the Douro Basin near Burgos (Spain). Currently, little is known about the distribution of Phoxinus bigerri in the Douro Basin. During early summer 2017, we sampled 75 stream reaches using electrofishing across the Douro Basin (Portugal and Spain). We identified 267 individuals as the Pyrenean minnow P. bigerri, and we cliped and stored fin tissues from 153 individuals in 96% ethanol for DNA reference collection. Among those, 26 were barcoded for cytochrome oxidase I (COI) and cytochrome b (Cytb) genes to confirm the taxonomic identification at the species level. Results confirmed for the first time the presence of the common minnow P. phoxinus in the Douro basin, being five individuals collected in the western Douro (Portugal near Porto) closely related to populations from Adour Basin in France. The remaining 21 individuals from eastern Douro (Spain near Brugos) were identified as P. bigerri, as expected. Our study is the first record of P. phoxinus in the Douro Basin, which can be easly missidentified when using only morphologically identifications. The study highlights the value of using molecular approaches for detecting new introductions and tracking spread histories, which can be relevant for designing proper management plans. The P. phoxinus introduction in western Douro (Portugal) seem to be related with human activities (sport fisheries by Portuguese immigrants living in France) rather than geographical proximity.
- First record of the freshwater jellyfish Craspedacusta sowerbii Lankester, 1880 in Greece suggests distinct European invasion eventsPublication . Karaouzas, Ioannis; Zogaris, Stamatis; Lopes-Lima, Manuel; Froufe, Elsa; Varandas, Simone; Teixeira, Amílcar; Sousa, RonaldoThis contribution presents the first record of the freshwater jellyfish Craspedacusta sowerbii Lankester, 1880 in Greece. The species was found in a water transfer canal adjacent to Lake Marathon, 45 km northeast of Athens; this is the southernmost record of this invasive alien medusa in the Balkan Peninsula and Europe. A review of recently published records shows that this species has expanded its range in Europe and the Mediterranean countries. Genetic analysis of the Greek specimen suggests that the phylogeny of C. sowerbii needs further evaluation since we are probably dealing with a distinct species within the genus Craspedacusta, and that the Greek population represents a distinct invasion event from that previously recorded in central Europe. However, due to a lack of molecular information on the native and invasive ranges, further phylogenetic studies are necessary to clarify this issue.
- Genetic diversity of the pan-European freshwater mussel Anodonta anatina (Bivalvia: Unionoida) based on CO1: new phylogenetic insights and implications for conservationPublication . Froufe, Elsa; Sobral, Carina; Teixeira, Amílcar; Sousa, Ronaldo; Varandas, Simone; Aldridge, David C.; Lopes-Lima, Manuel1. The duck mussel, Anodonta anatina, has been described as abundant and widespread in Europe. However, it is listed as near threatened or threatened in several countries owing to severe declines in abundance and/or spatial distribution. 2. Despite its potential ecological importance and conservation status almost nothing is known regarding its genetic diversity. 3. As a preliminary analysis, variation within the cytochrome oxidase 1 mitochondrial gene was determined from European specimens from Portugal in the south west, to Ukraine in the east, and Sweden in the north. 4. Three major mtDNA clades were retrieved: clade 1 includes all the individuals from Iberia, except those from the Ebro basin; clade 2 includes all the European non-Iberian and non-Italian samples; and clade 3 includes all the individuals from Italy and from the Ebro basin. AMOVA analysis revealed significant genetic differences among the three clades. Within each of the major clades, several geographically related haplogroups were also retrieved, especially in Iberia, where four genetically distinct groups (North-West, South-Central, South-West and Ebro) were revealed. 5. Given the evidence of regional declines of A. anatina in Europe, the confirmation of geographically distinct genotypes indicates a need for the development of management strategies directed towards the conservation of localized populations.
- Reproductive cycle and strategy of Anodonta anatina (L., 1758): Notes on hermaphroditismPublication . Hinzmann, Mariana; Lopes-Lima, Manuel; Teixeira, Amílcar; Varandas, Simone; Sousa, Ronaldo; Lopes, Anabela; Froufe, Elsa; Machado, JorgeFreshwater mussels have decreased dramatically in Iberia over the last decades. These animals are responsible for important ecosystem services such as recycling nutrients and improving water clarity. Under this view a better knowledge on the biological features of these animals is extremely important for future conservation and management actions. In this study the reproductive and gametogenic cycle of Anodonta anatina were studied during 2 years in one population as well as the sex ratio and hermaphroditism in six distinct populations, using standard histology. Gametogenesis was continuous in both sexes and germinal epithelium in early stages of development. Gametes were present throughout the reproductive cycle. Oogenesis and spermatogenesis occurred mainly between January and May. Larvae brooding occurred between September and March and main glochidia discharge occurred over a short period (2–3 weeks) in March. For the sex‐ratio and hermaphroditism assessments a variable number of individuals were collected from several populations from lakes and rivers. Previous studies described A. anatina as mainly dioecious with only a few populations presenting occasional hermaphroditism. However, the present study indicates that A. anatina sexual behavior is influenced by environmental conditions, being mainly dioecious in rivers with increased hermaphroditism in standing waters. Although selffertilization was not confirmed, additional studies with molecular characterization of larvae using fast evolving markers should be used in future studies to enlighten this process. Overall, this study indicates that for more efficient conservation actions and management plans, freshwater mussel reproductive biology should be studied at the population level mainly in the subfamily Anodontinae.
- Multiple introductions and first record of Phoxinus phoxinus in the Douro basin revealed by molecular dataPublication . Garcia-Raventós, Aina; Martins, Filipa; Magalhães, Maria Filomena; Ramião, José; Ferreira, Mário; Carona, Sara; Carvalho, Francisco; Sousa, Ronaldo; Froufe, Elsa; Teixeira, Amílcar; Varandas, Simone; Lopes-Lima, Manuel; Beja, Pedro; Filipe, Ana FilipaBiological invasions are a major threat to global biodiversity. Freshwater ecosystems are particularly vulnerable to anthropogenic introductions. This is the case of the minnows (Phoxinus genus), which have been used as a live bait since the 1900s. Until recently, Phoxinus phoxinus was thought to be distributed across most of the European watercourses, including the Iberian Peninsula (Ebro Basin and Cantabrian region). In 2007, these Iberian populations were identified as Phoxinus bigerri, including the traslocated populations in the Douro Basin near Burgos (Spain). Currently, little is known about the distribution of Phoxinus bigerri in the Douro Basin. During early summer 2017, we sampled 75 stream reaches using electrofishing across the Douro Basin (Portugal and Spain). We identified 267 individuals as the Pyrenean minnow P. bigerri, and we cliped and stored fin tissues from 153 individuals in 96% ethanol for DNA reference collection. Among those, 26 were barcoded for cytochrome oxidase I (COI) and cytochrome b (Cytb) genes to confirm the taxonomic identification at the species level. Results confirmed for the first time the presence of the common minnow P. phoxinus in the Douro basin, being five individuals collected in the western Douro (Portugal near Porto) closely related to populations from Adour Basin in France. The remaining 21 individuals from eastern Douro (Spain near Brugos) were identified as P. bigerri, as expected. Our study is the first record of P. phoxinus in the Douro Basin, which can be easly missidentified when using only morphologically identifications. The study highlights the value of using molecular approaches for detecting new introductions and tracking spread histories, which can be relevant for designing proper management plans. The P. phoxinus introduction in western Douro (Portugal) seem to be related with human activities (sport fisheries by Portuguese immigrants living in France) rather than geographical proximity.
- The strange case of the tetragenous Anodonta anatinaPublication . Lopes-Lima, Manuel; Hinzmann, Mariana; Teixeira, Amílcar; Varandas, Simone; Machado, Jorge; Sousa, Ronaldo; Froufe, ElsaUnionoid freshwater mussels have a unique life cycle with a form of parental care where the larvae are developed and kept inside the gills until release, followed by an obligate parasitic stage on fish. The size and location of the marsupium have been used as important phylogenetic characters in unionoids and in Anodontini its location was described exclusively on the outer demibranchs. Two recent surveys in a lake in the North of Portugal revealed large anodontine mussels morphological identical to Anodonta anatina but with glochidia in both demibranchs and with an unusual large size. In order to establish the identity of these mussels, a barcoding approach was used and an anatomical description of the gills and glochidia was performed. These mussels were identified as A. anatina and presented an inner demibranch pair with tripartite tubes. The glochidial sizes were much higher than previously reported for the species reaching maximum (length × height) values of 566 × 552 μm. This species reveals a high ecological plasticity being able to change its size and anatomy to increase its fertility as well as infestation performance. J. Exp. Zool. 9999A:XX-XX, 2015. © 2015 Wiley Periodicals, Inc.
- Ecological status of a Margaritifera margaritifera (Linnaeus, 1758) population at the southern edge of its distribution (River Paiva, Portugal)Publication . Amorim, Ângela; Sobral, Carina; Froufe, Elsa; Varandas, Simone; Teixeira, Amílcar; Lopes-Lima, ManuelAn important population of the critically endangered pearl mussel Margaritifera margaritifera (Linnaeus, 1758) was surveyed at the edge of its southern distribution (River Paiva, Portugal). Although an earlier study suggested that this population had a very low number of individuals (<500), a narrow distribution, and was mainly comprised by old specimens our data contradict these findings. Our assessment estimated a population with probably more than 5,000 individuals distributed across 80 km of the river length. From the 32 sites surveyed, 19 contained M. Margaritifera with higher abundances verified in the middle and upper parts of the river (a maximum of 78 ind. per 100 m of river stretch was recorded). The pearl mussels showed a clear preference for areas near the banks, in shallow water, sandier and gravel sediments, and a high degree of riparian vegetation cover. The population structure was skewed with a very high percentage of large (and old) animals but 3.7 % of the individuals collected were juveniles (\60 mm in length); therefore, this population can be considered functional. Environmental characterization indicated that this river is still in excellent or good condition although some areas showed deterioration due to discharge of domestic effluents. The main conservation requirements of M. margaritifera in the River Paiva include maintaining the water quality (and if possible stopping the discharge of domestic effluents), increasing riparian vegetation cover, removing several weirs to increase connectivity, and increasing trout density.