Three new cryptic species of the lamprey genus Lampetra Bonnaterre, 1788 (Petromyzontiformes: Petromyzontidae) from the Iberian Peninsula.

The Iberian Peninsula is a repository for biodiversity, presenting high levels of endemism in both plants and animals. In this peninsular region, brook lampreys confined to small, isolated river basins evolved in allopatry giving rise to evolutionary lineages, as revealed by mitochondrial DNA markers. For a better understanding of the taxonomic status and relationships of Iberian populations of the genus Lampetra, we combined previous data from genetics and morphological analysis (assessed here), and describe three new species of the lamprey genus Lampetra Bonnaterre, 1788 in Portugal. In this region L. planeri actually represent a complex of cryptic species, each having smaller geographic ranges than L. planeri, and consequently, greater vulnerability to extinction. The description of Lampetra alavariensis sp. nov. is based on 36 specimens collected on Ribeira de Mangas, a tributary of river Esmoriz, in Northern Portugal. Lampetra auremensis sp. nov. is described on the basis of 31 specimens collected on Ribeira do Olival, a small tributary of river Nabão (Tagus basin). Finally, Lampetra lusitanica sp. nov. is described based on 38 specimens from Ribeira da Marateca, Sado river basin, the southernmost distribution of the genus Lampetra. The recognition of these new species will contribute to the conservation of these already imperilled taxa and will help prevent the extinction of three important evolutionary lineages

Trace elements accumulation in the sea lamprey along the major hydrographic basins of Portugal

Trace elements accumulation in the sea lamprey along the major hydrographic basins of Portuga

Structural lipid changes and Na+/K+-ATPase activity of gill cells'basolateral membranes during saltwater acclimation in sea lamprey (Petromyzon marinus, L.) juveniles

Seawater acclimation is a critical period for anadromous species and a process yet to be understood in lampreys. Considering that changes in lipid composition of the gill cells' basolateral membranes may disrupt the major transporter Na+K+-ATPase, the goal of this study was to detect changes at this level during juvenile sea lamprey seawater acclimation. The results showed that saltwater acclimation has a direct effect on the fatty acid composition of gill cells basolateral membrane's phospholipids. When held in full-strength seawater, the fatty acid profile of basolateral membrane's phospholipids suffered a restructure by increasing either saturation or the ratio between oleic acid and eicosapentaenoic acid. Simultaneously, the activity of Na+K+- 2 ATPase revealed a significant and positive correlation with basolateral membrane's cholesterol content in the presence of highest salinity. Our results pointed out for lipid adjustments involving the functional transporter present on the gill cell basolateral membranes to ensure the role played by branchial Na+K+-ATPase in ion transport during saltwater acclimation process. The responses observed contributed to the strategy adopted by gill cell's basolateral membranes to compensate for osmotic and ionic stressors, to ensure the success of the process of seawater acclimation associated with the downstream trophic migration of juvenile sea lamprey.This work was financially supported by the Foundation for Science and Technology (FCT) project PTDC/BIA-BEC/103258/2008 and project UID/MAR/04292/2013 (national funds FCT/MEC–PIDDAC through Acordo de Parceria PT2020)

Session D2: Coimbra Fishway: Restoring Connectivity in River Mondego

Abstract: River Mondego is the largest Portuguese river with its basin entirely within national territory. The Açude-Ponte dam was built in Mondego in the 80’s, along with three other large dams to mitigate floods and to allow the integrated use of river basin water resources for hydroelectric power generation, public supply, industry and irrigation. Considering the river importance for several fish species, namely sea-lamprey and shad, a fishway was constructed. Several structural and hydraulic problems soon revealed that this fishway was inefficient therefore this dam became the first impassable obstacle in the River Mondego. In 2011, after several years of biological and hydraulic monitoring, and once the reasons for the fishway inefficiency were perfectly identified, a vertical-slot fishway was built to restore river connectivity. The efficiency and effectiveness of the Coimbra Fishway has been studied since 2012 using several monitoring techniques (visual counts, biotelemetry techniques and CPUE abundance with electrofishing). Monitoring results show that several autochthonous species use the fishway, including the diadromous sea-lamprey, allis and twaite shad and European-eel. More than 1,500.000 fish have used the fishway during the upstream or downstream migration. PIT telemetry has shown an efficiency of 30% for Petromyzon marinus and 14% for Luciobarbus bocagei. Pre and post fishway construction electrofishing monitoring shows improvements in sealamprey larvae abundance both upstream and downstream from the Açude-Ponte dam. Coimbra Fishway project is improving fish migration in River Mondego, but it’s also an integrated project involving other important aspects such as fisheries and river basin management and environmental education. Changes in exploitation regimes of upstream hydropower dams and in the Açude-Ponte are also planned to increase the fishway efficiency. Finally, several activities have been carried out in association with this project to raise public awareness regarding environmental issues, particularly those related with river longitudinal continuity

Trace element accumulation in anadromous sea lamprey spawners

The sea lamprey, Petromyzon marinus, is an anadromous cyclostome that occurs in the main Western Europe river basins draining to the Atlantic Ocean and considered a gastronomic delicacy in Portugal, Spain and France. The contamination profile of this species is fairly unknown as far as trace metals are concerned, with only a few studies dedicated to the subject. Trace elements concentration was analysed in muscle and liver samples of adult specimens from eight Portuguese river basins. This study aimed: (i) to assess the profile of essential and nonessential elements accumulation in the muscle and liver of sea lamprey spawners; (ii) to investigate possible differences in the trace element accumulation in adult sea lampreys entering Portuguese river basins; and (iii) to determine the safety of sea lamprey for human consumption regarding elements content. Females accumulated higher levels of elements than males, but only differences in the liver were significant. In a general overview, the accumulation of most elements analysed was low, except for Hg in the muscle, which exceeded the statutory limits for fish concentration. The muscle accumulation profile based on nonessential elements (As, Cd and Hg) evidenced a segregation of the samples into two groups, mostly based on Hg concentration. Distinct trophic levels and contamination of preys and differential duration of the parasitic period may be in the origin of this separation

Salinity and Atrazine Sublethal Levels Induce Gill Cells Basolateral Membrane Phospholipids Modulation in Sea Lamprey Downstream Migrants

Conditions experienced by anadromous fishes while in freshwater may be critical to their subsequent survival in the sea. During the trophic migration to the ocean, juveniles of sea lamprey (Petromyzon marinus L.) are exposed to several stress factors, including different types of pollutants. We analyzed gill histopathological biomarkers, characterized the lipid profile of the basolateral membrane (BLM) of gill cells, and determined NKA activity, in order to evaluate if BLM lipid profile system plays a part in modulation of NKA activity and may be involved in the successful acclimation of sea lamprey juveniles during downstream migration

Meso- and Micro-Habitat Preferences of European River and Brook Lamprey in a Mediterranean River Basin

The European river (Lampetra fluviatilis Linnaeus, 1758) and brook (Lampetra planeri Bloch, 1784) lampreys are considered ‘paired species’, i.e., they are closely related and morphologically very similar but have distinct modes of adult life (anadromous vs. resident). In the Iberian Peninsula, the southern limit of both species’ distribution, they face different pressures (e.g., barriers, pollution, hydrological stress) that reduce the available habitat, which is exacerbated by the actual climate change context. The main objective of the present study was to evaluate meso- and microhabitat preferences of Lampetra sp. On the mesohabitat scale, the environmental variables that influence these species’ distributions on the watershed scale were identified. On the microhabitat level, besides identifying the fine-scale variables that influence the presence and abundance of Lampetra sp., possible changes in habitat preferences throughout the larval stage (i.e., distinct size/age classes) were also assessed. Mesohabitat results suggest that the relative abundance of Lampetra sp. is related to variables such as pH and riparian vegetation. Regarding the microhabitat, the relative abundance of the size classes’ distribution seems to be associated with variables such as substrate granulometry. The results in terms of habitat preferences on a Mediterranean basin are discussed in the context of a climate change scenario (e.g., decrease in habitat quality and availability) and management and conservation perspective

Evidence of Genetic Segregation among Meagre (Argyrosomus regius) Atlantic Spawning Areas

The meagre Argyrosomus regius, one of the largest sciaenidae in the world, is a valuable resource for fisheries and aquaculture. Despite its socioeconomic relevance, knowledge about population dynamics and wild stocks is still scarce, and conservation risks are associated with overexploitation. Two genetic distinct groups, one in the North Atlantic Ocean and one in the eastern Mediterranean Sea, were identified by previous studies. However, little is known about the genetic structure of the Atlantic group, where four important spawning areas have been identified. To assess if each spawning area is an independent breeding unit, the genetic diversity, populational structure, and demographic history of A. regius along the North-East and Eastern Central Atlantic coast were analyzed, using 15 microsatellite loci. Results corroborate the hypothesis tested, suggesting four genetic groups: a first group encompassing individuals from the Gironde spawning area, a second group encompassing individuals from the Tagus spawning area, a third group corresponding to individuals captured in the Algarve region, and a forth group gathering individuals from Morocco and Mauritania. This study reveals the need for specific fisheries management plans considering genetic structure information, and highlights the need for international cooperation

Effects of hydropeaking on the behaviour, fine-scale movements and habitat selection of an Iberian cyprinid fish

Hydropeaking is widely known for changing the quantity and quality of the available habitat downstream of hydroelectric facilities, thus affecting all stages of fish life cycles. Hydropeaking impacts on salmonids are widely studied, but knowledge of its effects on cyprinids, which are dominant in Mediterranean areas, is scarce. In this study, 11 Iberian barbel (Luciobarbus bocagei, Steindachner 1864) were tagged with radio transmitters equipped with ElectroMyoGram (EMG) sensors, aiming: to (a) assess the behaviour, fine-scale movements and habitat selection of the target species in response to periods of artificial and abrupt flow variations (i.e., hydropeaking); and (b) identify, which environmental variables and, in particular, flow components can influence the species behaviour. Results from the six barbel that provided analysable data indicate that fish were more active during the day and in periods of ecological flow. Moreover, during hydropeaking, especially during the increase in flow magnitude, fish activity decreased with the tagged fish showing a refuge-seeking behaviour. This information can be used to minimize the changes caused in the aquatic habitat and fish communities occurring downstream of hydroelectric dams