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-Phoxinus phoxinus in the Seine catchment: m from the Beuvron Stream, Ouagne 47°24'N, 3°29.7'E, MNHN 2014-2748 (A); f from the Oise Stream, Gergny 49°54.6'N, 3°56.1'E, MNHN 2014-2724 (B), nuptial colouration pattern for male (C) and female (D).
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French minnows of the genus Phoxinus are revised based on molecular data (COI and 12S rDNA markers), morphological characters and nuptial colouration patterns. The results delineate six groups of populations, which are recognised as species. Phoxinus phoxinus is found in eastern France in the lower and middle Rhine and Seine drainages. Phoxinus big...
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... bars of variable widths crossing Z2 to Z4 and no stripe long Z3 (vs. presence of a stripe in Z3), the bars are black in Z2 and green in Z3 and Z4 (vs. black from Z2 to Z3). Z2 is golden-yellow (vs. light brownish), Z4 green-yellowish (vs. uniform green, yellow or greyish). Lips as well as pectoral, pelvic and anal fin bases are pinkish (vs. red) (Fig. 6A, C). In the nuptal female, Z4 is green (vs. yellow or greyish), and it has a black line in Z5 between the pectoraland anal fin bases (vs. absent) (Fig. 6B, D). Phoxinus phoxinus is distinguished from P. biggeri by having 75-99 scales in the lateral series (vs. 68-87), a slightly pointed snout (vs. very stout), a subterminal mouth (vs. ...
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... from Z2 to Z3). Z2 is golden-yellow (vs. light brownish), Z4 green-yellowish (vs. uniform green, yellow or greyish). Lips as well as pectoral, pelvic and anal fin bases are pinkish (vs. red) (Fig. 6A, C). In the nuptal female, Z4 is green (vs. yellow or greyish), and it has a black line in Z5 between the pectoraland anal fin bases (vs. absent) (Fig. 6B, D). Phoxinus phoxinus is distinguished from P. biggeri by having 75-99 scales in the lateral series (vs. 68-87), a slightly pointed snout (vs. very stout), a subterminal mouth (vs. terminal or slightly subterminal), a straight to slightly concave anal fin margin (vs. straight to convex), and the caudal peduncle depth 2.8-3.9 times in its ...
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... suboperculum. Z1 blackish. No stripe long Z3. Bars of variable widths crossing Z2 to Z4, bars black in Z2 and green in Z3 and Z4. Z4 greenish yellow, bars poorly contrasted on Z4. Bars distinct on caudal peduncle. Z5 greyish to blackish. Belly pinkish or light orange. Mouth as well as bases of pectoral, pelvic and anal fins with a pinkish tinge (Fig. 6A, ...
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... In the last 20 years, however, their status has changed dramatically as first some morphological studies (Bogutskaya et al. 2004;Kottelat 2007) and later molecular studies (Geiger et al. 2014;Palandačić et al. 2017;Palandačić et al. 2020) have revealed a high level of genetic diversity within this group of fishes. Currently, more than 23 genetic lineages are known in Europe, of which 14 are recognised as valid species (Palandačić et al. 2017;Denys et al. 2020;Bogutskaya et al. 2023). ...
We are in a time of rapid change on multiple levels. Change can be seen as positive by one group and negative by another. As a result, different perspectives on any given change can draw completely different conclusions. In these proceedings we want to address different approaches to change from all kinds of perspectives within the realm of citizen science and participatory research. We discuss both active, transformative change, and the observation of change monitored by citizen science in all kinds of disciplines. We highlight the potential of citizen science to be a change maker in research and society, and as a tool to manage the change happening around us. The proceedings "Change - The transformative power of citizen science" showcase a selection of topics that have been presented and discussed at the ECSA/ACSC 2024 double conference in Vienna and highlight the transformative power, citizen science can have.
... In the last 20 years, however, their status has changed dramatically as first some morphological studies (Bogutskaya et al. 2004;Kottelat 2007) and later molecular studies (Geiger et al. 2014;Palandačić et al. 2017;Palandačić et al. 2020) have revealed a high level of genetic diversity within this group of fishes. Currently, more than 23 genetic lineages are known in Europe, of which 14 are recognised as valid species (Palandačić et al. 2017;Denys et al. 2020;Bogutskaya et al. 2023). ...
... (Teleostei: Leuciscidae) are cryophilic and rheophilic species spanning a wide range of habitats throughout Eurasia (Freyhof & Kottelat, 2007;Keith et al., 2020). The total number of Phoxinus species is yet to be determined, as this genus' taxonomy is still being explored following advances in molecular tools (e.g., Bogutskaya et al., 2020Bogutskaya et al., , 2023Denys et al., 2020;Palandači c et al., 2015Palandači c et al., , 2017Turan et al., 2023). Several difficulties are encountered in the species delineation in this genus: (1) This genus is an example of cryptic diversity highlighted by molecular data (Bayçelebi et al., 2024;Bogutskaya et al., 2023;Corral-Lou et al., 2019;Denys et al., 2020;Kottelat, 2007;Palandači c et al., 2017;Vuci c et al., 2018;Turan et al., 2023); (2) there is phenotypic diversity within the genetic lineages (Bianco & De Bonis, 2015;Bogutskaya et al., 2020;Collin & Fumagalli, 2015;Ramler et al., 2017); (3) in Europe, the distribution of lineages and species tends not to follow zoogeographical patterns and to cross drainage basin boundaries (Corral-Lou et al., 2019;Denys et al., 2020;De Santis et al., 2021;Garcia-Raventós et al., 2020;Palandači c et al., 2015Palandači c et al., , 2017Palandači c et al., , 2020Palandači c et al., , 2022, (4) different genetic lineages were shown to produce hybrids under natural conditions (Corral-Lou et al., 2019;Palandači c et al., 2015Palandači c et al., , 2017; and (5) the resulting management of minnows-if there is any-was further blurred by numerous anthropogenic introduction events. ...
... The total number of Phoxinus species is yet to be determined, as this genus' taxonomy is still being explored following advances in molecular tools (e.g., Bogutskaya et al., 2020Bogutskaya et al., , 2023Denys et al., 2020;Palandači c et al., 2015Palandači c et al., , 2017Turan et al., 2023). Several difficulties are encountered in the species delineation in this genus: (1) This genus is an example of cryptic diversity highlighted by molecular data (Bayçelebi et al., 2024;Bogutskaya et al., 2023;Corral-Lou et al., 2019;Denys et al., 2020;Kottelat, 2007;Palandači c et al., 2017;Vuci c et al., 2018;Turan et al., 2023); (2) there is phenotypic diversity within the genetic lineages (Bianco & De Bonis, 2015;Bogutskaya et al., 2020;Collin & Fumagalli, 2015;Ramler et al., 2017); (3) in Europe, the distribution of lineages and species tends not to follow zoogeographical patterns and to cross drainage basin boundaries (Corral-Lou et al., 2019;Denys et al., 2020;De Santis et al., 2021;Garcia-Raventós et al., 2020;Palandači c et al., 2015Palandači c et al., , 2017Palandači c et al., , 2020Palandači c et al., , 2022, (4) different genetic lineages were shown to produce hybrids under natural conditions (Corral-Lou et al., 2019;Palandači c et al., 2015Palandači c et al., , 2017; and (5) the resulting management of minnows-if there is any-was further blurred by numerous anthropogenic introduction events. Introductions have been documented for several species and are reported to result from the use of Phoxinus minnows as live bait for trout angling (Corral-Lou et al., 2019;De Santis et al., 2021;Miró & Ventura, 2015;Palandači c et al., 2020Palandači c et al., , 2022, even if the study of the mosaic-like distribution created through translocations is still at its very beginning. ...
... The total number of Phoxinus species is yet to be determined, as this genus' taxonomy is still being explored following advances in molecular tools (e.g., Bogutskaya et al., 2020Bogutskaya et al., , 2023Denys et al., 2020;Palandači c et al., 2015Palandači c et al., , 2017Turan et al., 2023). Several difficulties are encountered in the species delineation in this genus: (1) This genus is an example of cryptic diversity highlighted by molecular data (Bayçelebi et al., 2024;Bogutskaya et al., 2023;Corral-Lou et al., 2019;Denys et al., 2020;Kottelat, 2007;Palandači c et al., 2017;Vuci c et al., 2018;Turan et al., 2023); (2) there is phenotypic diversity within the genetic lineages (Bianco & De Bonis, 2015;Bogutskaya et al., 2020;Collin & Fumagalli, 2015;Ramler et al., 2017); (3) in Europe, the distribution of lineages and species tends not to follow zoogeographical patterns and to cross drainage basin boundaries (Corral-Lou et al., 2019;Denys et al., 2020;De Santis et al., 2021;Garcia-Raventós et al., 2020;Palandači c et al., 2015Palandači c et al., , 2017Palandači c et al., , 2020Palandači c et al., , 2022, (4) different genetic lineages were shown to produce hybrids under natural conditions (Corral-Lou et al., 2019;Palandači c et al., 2015Palandači c et al., , 2017; and (5) the resulting management of minnows-if there is any-was further blurred by numerous anthropogenic introduction events. Introductions have been documented for several species and are reported to result from the use of Phoxinus minnows as live bait for trout angling (Corral-Lou et al., 2019;De Santis et al., 2021;Miró & Ventura, 2015;Palandači c et al., 2020Palandači c et al., , 2022, even if the study of the mosaic-like distribution created through translocations is still at its very beginning. ...
Phoxinus minnows are small freshwater fish found throughout Eurasia. The taxonomy of this genus is still under investigation, and new species are regularly described. They are frequently introduced outside their native range due to their use as live bait for angling, and such fish introductions can have diverse impacts on the recipient areas. Before the rise in interest regarding the diversity of this genus in the past 15 years, studies carried out on their biology and ecology reported their findings for the Eurasian minnow Phoxinus phoxinus Linnaeus, 1758, which was then considered ubiquitous. A parasites checklist for Phoxinus minnows has yet to be published, and the recent progress on the taxonomy of this genus has enabled us to propose a reassignment of parasite records to their proper host. The most thoroughly studied potential species were the North European species Phoxinus sp. 7 sensu Palandačić et al. 2017, Phoxinus isetensis, and P. phoxinus. We were able to highlight a gap in knowledge for numerous species that have received little‐to‐no attention in terms of parasitology. Systematic molecular identification of Phoxinus minnows should be conducted when studying their parasites, as a reliable identification of the host is vital in parasitology research. Future research will certainly reveal a species‐specific composition of the parasitofauna occurring in Phoxinus, especially among widespread parasites such as Gyrodactylus and Diplostomum. Such specificities could even become tools for assessing the introduction routes of Phoxinus species.
... and Salmo trutta). Moreover, two of the four taxa (i.e., Alburnoides bipunctatus and Rhodeus amaratus) showing signs of improvement are supposed to have increased their range mainly through human driven translocation and water temperature increase (Van Damme et al., 2007;Keith et al., 2020). The foregoing makes the Tison-Rosbery et al. (2022) statement of a recovery of pollution-sensitive taxa not fully supported by our results, at least during the time range of our study. ...
We evaluate, for the first time, variations of the national Fish-Based-Index (FBI) over a seventeen-year period for 1583 sampled sites evenly distributed across the French territory. As far as we know this is one of the first studies analyzing the temporal trends of a fish-based biotic indicator for such a consistent set of records going back over almost two decades. Our results provide four important insights. First, the index is efficient in discriminating sites in good condition from sites experiencing anthropogenic disturbances. Second, according to the index, the ecological state of French riverine fish assemblages is rather poor, as around half of the assessed sites, thought to reflect the diverse conditions within the French riverine system, are significantly impaired. Third, according to the index, there is no noticeable amelioration through time of sites fish assemblage structure and function despite management efforts initiated two decades ago to comply with the EU’s 2000 Water Framework Directive. Fourth, the index might start being influenced by climate change as early signs of response to warming are happening since the last 10 yr. According to the FBI, the current efforts for improving the biological condition of riverine systems in France are not yet creating desired outcomes.
... Due to their complex taxonomy, they have been the focus of many recent studies (Bogutskaya et al., 2019;Corral-Lou et al., 2019;Palandači c et al., 2015Palandači c et al., , 2017aPalandači c et al., , 2020Vuci c et al., 2018), which revealed a high molecular and morphological diversity that was not fully consistent with previous taxonomic concepts based solely on morphology (B an arescu, 1992;Kottelat, 2007;Kottelat & Freyhof, 2007). These studies indicated, on the one hand, morphologically diagnosable clades corresponding to species (Bayçelebi et al., 2024;Bogutskaya et al., 2019;Denys et al., 2020;Palandači c et al., 2017a;Turan et al., 2023) and, on the other hand, a number of clades that still require an integrative research to clarify their phylogeny and taxonomic identity (Corral-Lou et al., 2019;De Santis et al., 2020;Palandači c et al., 2017a). Among the highlighted problems to be addressed were the high intraspecific phenotypic diversity, which makes it difficult to diagnose morphologically similar species (Bogutskaya et al., 2019), and the insufficient information provided by the currently analysed molecular markers for final species delimitation . ...
... Therefore, this study showed that phenotypic diversity is a problem for Phoxinus taxonomy, and morphology alone cannot be diagnostic for most species. There are characters that delimit some species (Bogutskaya et al., 2019;Denys et al., 2020), but in general, there are no discrete morphological groups, especially within an expanded sample set. P. bigerri, the geo- were not species-identifying in this study (e.g., Denys et al., 2020). ...
... There are characters that delimit some species (Bogutskaya et al., 2019;Denys et al., 2020), but in general, there are no discrete morphological groups, especially within an expanded sample set. P. bigerri, the geo- were not species-identifying in this study (e.g., Denys et al., 2020). -8). ...
The present drainage network of Bulgaria is the result of a complex Neogene and Quaternary evolution. Karst, which has developed on 23% of the territory, further complicates the hydrological pattern. Fresh waters of Bulgaria drain into the Black Sea and the Aegean Sea basins and can be roughly divided into the Danube (Middle and Lower Danube), non‐Danube Black Sea, East Aegean, and West Aegean hydrological regions. Phoxinus, a small leuciscid fish, has a mosaic distribution in all four of these regions, inhabiting small mountainous and semi‐mountainous streams. Based on morphology, it was identified as three species, Phoxinus phoxinus in the Danube, Phoxinus strandjae in the non‐Danube, and Phoxinus strymonicus in West Aegean region. Later, molecular data revealed Phoxinus csikii and Phoxinus lumaireul in the Middle Danube and P. csikii in the Lower Danube. Phoxinus has been the focus of many studies, showing a high molecular and morphological diversity, which is not entirely consistent with previous morphology‐only‐based taxonomic concepts. In this study, molecular (a mitochondrial marker and a nuclear marker) and morphological data from both historical and recently sampled collections were analysed to assess the applicability of the integrative approach in Phoxinus. The results showed a significant influence of the complex paleo‐ and recent hydrology on the currently observed genetic structure of the considered populations and species. Furthermore, the study also demonstrated a strong influence of phenotypic plasticity on the morphological analysis of Phoxinus and the lack of a clear differentiation between P. csikii and P. strandjae. A barcoded specimen was designated as neotype to fix the species named P. strandjae in the current taxonomic concept. Finally, a significant discordance between genetically delimited clades and phenotypic groups did not allow a proper delineation of the species distributed in Bulgaria, demonstrating that more molecular markers are needed for further taxonomic study of the Phoxinus complex.
... One such example of cryptic diversity is the case of minnows Phoxinus spp. (Leuciscidae) (Kottelat 2007;Palandačić et al. 2017;Corral-Lou et al. 2019;Denys et al. 2020), small freshwater fish widely distributed across Eurasia, for which reliable diagnosis on the field is impeded by the difficulty of observing the diagnostic characters (Bianco 2014), except the nuptial coloration pattern shown in French species , i.e. only during their spawning period. ...
... only during their spawning period. There are currently 26 valid Phoxinus species in Eurasia (Berg 1949;Mitrofanov et al. 1987;Chen 1988;Kottelat 2006Kottelat , 2007Bianco and De Bonis 2015;Zhang and Zhao 2016;Palandačić et al. 2017;Bogutskaya et al. 2020Bogutskaya et al. , 2023Denys et al. 2020;Dyldin et al. 2023;Turan et al. 2023;Artaev et al. 2024;Bayçelebi et al. 2024), 5 more molecular lineages potentially corresponding to distinct species (Palandačić et al. 2017) and the taxonomy of this genus is still under study, owing notably on the emergence of molecular tools. Within the genus, several introduction events have been documented e.g. ...
... Corral-Lou et al. (2019) highlighted the introduction in Catalonia of P. septimaniae and of a lineage from the Garonne which may be Phoxinus dragarum Denys, Dettai, Persat, Daszkiewicz, Hautecoeur and Keith, 2020 which is endemic to the Garonne drainage basin. Similarly, Denys et al. (2020) affirmed the introduction of P. dragarum in the Guadalquivir drainage basin on the basis of the nuptial coloration of the specimen illustrated by Sáez-Gómez and Prenda (2019). Garcia-Raventós et al. (2020) noted the introduction of a population from the Charente drainage basin (Western France) in the Sousa river (Portugal). ...
The introduction of freshwater fish species is a leading cause of aquatic biodiversity erosion and can spread parasites to native populations. Hidden diversity evidenced by recent taxonomic revisions can add further complexity to the issue by rendering biological assessment data incomplete. The Eurasian minnows Phoxinus are one such example of cryptic diversity, with several described species being invasive. Current non-native fish populations in the small Mediterranean island of Corsica (France) are the result of successive waves of introductions, including several Phoxinus species. This study aims at determining which Phoxinus species were introduced to Corsica using the cytochrome oxidase subunit I barcoding marker, reconstructing their introduction routes and examining their parasite communities. The study found four species in Corsica: Phoxinus phoxinus and Phoxinus csikii mainly in the northernmost studied drainage basin and Phoxinus dragarum and Phoxinus septimaniae in the Tavignano drainage basin. P. phoxinus and P. csikii were most likely introduced through a live bait wholesaler while P. dragarum and P. septimaniae were probably introduced by recreational anglers bringing their bait from continental France. The molecular study of their Gyrodactylus (Platyhelminthes: Monogenea) parasites with the ITS marker allowed us to hypothesize inter-drainage basin secondary introduction routes for P. phoxinus and P. dragarum. In several sampling sites, Phoxinus minnows had black spot disease caused by encysted metacercariae of Digenea, likely Posthodiplostomum cuticola. These parasites were also found on the brown trout Salmo trutta in a locality where this patrimonial species co-occurs with Phoxinus minnows. Barcoding should be used in fish communities monitoring to help to accurately identify cryptic species.
... Before the implementation of genetic methods to the taxonomy, the genus Phoxinus was represented by a few species despite its wide geographic range (Kottelat 1997). Although detailed morphological studies still contribute to identification of new species in Phoxinus (Kottelat 2007;Bianco and De Bonis 2015), introduction of genetic methods to Phoxinus taxonomy has resulted in a significant increase in the numbers of newly described species, and taxonomic and geographic range revisions (Palandačić et al. 2015(Palandačić et al. , 2017(Palandačić et al. , 2020Vucić et al. 2018;Denys et al. 2020;Turan et al. 2023). In particular, recent genetic studies have revealed: i) deep genetic divergences within the genus, and ii) presence of numerous yet undescribed species. ...
Taxonomic revision of Phoxinus from the Caucasus revealed two distinct species. One species, P. colchicus, was known from eastern drainage of Black Sea, but was recorded also in the middle reach of the Kuban (Sea of Azov basin), for the first time. The Kuban population represents a genetically unique sub-lineage of P. colchicus. Its ancestors might have colonized the Kuban system through the event of ancient river capture. Another species inhabits only the Adagum River basin in the lower Kuban and represents a new narrow-ranged endemic species-Phoxinus adagumicus sp. nov. According to mtDNA phylogeny (COI and cytb), P. adagumicus sp. nov. represents deeply divergent and one of the two early branched lineages of the genus Phoxinus being distant to other species (min. p-distance = 0.074) including geographical neighbors-P. chrysoprasius from Crimean Peninsula and P. colchicus from the Caucasus. The new species differs from most Phoxinus species by frequently occurring single-row pharyngeal teeth (modal formula 5-4). The narrow geographic range (ca. 55 km in length and 15-20 km in width) and high anthropogenic load on local water systems suggests the new species is under threat and needs protection.
... All European minnows were previously identified as Phoxinus phoxinus (Linnaeus 1758). With the development of molecular and morphological techniques, numerous Phoxinus species' designations as synonyms of P. phoxinus (such as the list of synonyms published by Kottelat 2007) started to be questioned (Palandačić et al. 2015(Palandačić et al. , 2017(Palandačić et al. , 2020Vucić et al. 2018;Bogutskaya et al. 2019Bogutskaya et al. , 2023Denys et al. 2020;Turan et al. 2023). The first study on this was by Kottelat (2007), who described three species from Greece and southern France. ...
... The latest studies, P. krkae Bogutskaya et al. (2019), described a new minnow from Croatia and initially identified it as a molecular clad and Palandačić et al. (2020) researched museum collections to help with the genetic evaluation of species introductions in freshwater fishes (Cyprinidae: Phoxinus species complex): European minnows through time. In 2020, Denys et al. (2020) revised Phoxinus in France and described two new species (Teleostei, Leuciscidae) and also created zones of coloration in Phoxinus. Finally, Turan et al. (2023) described a new species from Türkiye. ...
Phoxinus radeki , a new species, is described from the Ergene River (Aegean Sea Basin). It is distinguished from Phoxinus species in Türkiye and the adjacent area by having the scales of the breast, scaled but separated unscaled area anteriorly, short dark rectangular blotches along the lateral line between the lateral line and belly yellowish in both males and females, body depth dorsal fin origin 16–21% SL, caudal peduncle depth 8–10% SL. Additionally, molecular results demonstrated that the new species differed from its closest congeners with a mean genetic distance value of 3.08% (min. 2.82–max. 3.29) and moderately support values in cytochrome b (Cyt b ) gene partial sequences (1064 bp.). Further, the species delimitation analysis identified the new species as a single MOTU independent of other Phoxinus species.
... Here, we focused on the most abundant Gammarid species in the area that we named hereafter Gammarus sp. as this species has not yet been officially named, although it has been shown to be phylogenetically independent from its most closely related species, Gammarus fossarum (Carnevali 2022, Piscart unpubl.). For the fish species, we focused on the Occitanean minnow P. dragarum, a Cyprinid species measuring ~ 50-90 mm as an adult and abundant in cold rivers (Denys et al. 2020). It is a gregarious and omnivorous species Figure 1. ...
Testing whether intra- and interspecific biodiversity facets co-vary spatially across trophic levels is of utmost importance to generalize processes driving biodiversity patterns in natural landscapes. Similar processes are expected to act on intra- and interspecific diversity, which should lead to positive co-variation between genetic and species diversity. Although this prediction has been verified within trophic levels, it has rarely been tested across multiple trophic levels. To meet this challenge, we focused on a riverine freshwater ecosystem in which we sampled intra- (genomic diversity) and interspecific (species diversity) data across three trophic levels: riparian trees, benthic macroinvertebrates and fishes. For each trophic level, we quantified α- and β-diversity at both the intra- (SNP diversity within populations of Alnus glutinosa, Gammarus sp. or Phoxinus dragarum) and interspecific levels (species diversity within communities). We first tested for a global spatial co-variation of diversity across trophic levels and diversity facets. We then tested whether relevant environmental parameters similarly affected each biodiversity estimate and explained potential spatial co-variation among biodiversity components. We did not evidence any spatial co-variation of biodiversity across trophic levels and diversity facets, neither for α- nor for β-diversity. We found that sites situated in the Western part of the sampling area had higher α-diversities, and that highly connected sites had lower β-diversities, which holds true for all trophic levels and diversity facets. Nonetheless, the effects of other environmental predictors were specific to each biodiversity component, likely explaining the absence of spatial co-variation among biodiversity components. Our study demonstrates that global biodiversity patterns in rivers can be hard to generalize and are rather idiosyncratic, even though a few processes might have consistent impacts on biodiversity components across trophic levels.
... Here, we compared estimates of genetic diversity and differentiation and spatial patterns of genetic variability using both STR and SNP data from two freshwater fish species inhabiting a large dendritic river network in southwestern France: the Garonne minnow (Phoxinus dragarum [31]) and the Languedoc gudgeon (Gobio occitaniae [32]). In both species, SNPs were obtained from a pool-seq procedure [17] and mapped to newly developed genome assemblies. ...
... The study took place in two large river basins in southern France: the Garonne and the Dordogne watersheds. We focused on two abundant cyprinid species: the Garonne minnow Phoxinus dragarum [31] and the Languedoc gudgeon Gobio occitaniae [32]. These two cyprinid species are often found in sympatry, usually in fresh shallow waters. ...
Biodiversity is facing an unprecedented crisis and substantial efforts are needed to conserve natural populations, especially in river ecosystems. The use of molecular tools to guide conservation practices in rivers has grown in popularity over the last decades, but the amount of precision and/or biological information that would be gained by switching from the traditional short tandem repeats (STRs) to the increasingly used single nucleotide polymorphisms (SNPs) is still debated. Here, we compared the usefulness of STRs and SNPs to study spatial patterns of genetic variability in two freshwater fish species (Phoxinus dragarum and Gobio occitaniae) in southern France. SNPs were obtained from a pool-seq procedure and mapped to new genome assemblies. They provided much more precise estimates of genetic diversity and genetic differentiation than STRs, but both markers allowed the detection of very similar genetic structures in each species, which could be useful for delineating conservation units. While both markers provided similar outcomes, there were two discrepancies in genetic structures that could, nonetheless, be explained by unrecorded stocking events. Overall, we demonstrated that SNPs are not unconditionally superior to STRs in the context of large-scale riverscape genetic conservation, and that the choice of marker should primarily be based on research questions and resources available.
