Long-term monitoring of the fish community in the Minho Estuary (NW Iberian Peninsula).

Background: The paper presents an extensive fish sampling dataset spanning a long-term period from 2010 to 2019. The data were collected in Lenta Marina, an upstream area in the Minho Estuary of the NW Iberian Peninsula, which belongs to a LTSER (Long-Term Socio-Ecological Research) platform. To capture fish, fyke nets were utilised as the sampling method and deployed at Lenta Marina. This dataset offers valuable insights into the abundance of each collected taxa recorded over time. New information: The dataset reports a comprehensive compilation of data on the abundance of fish species observed in the area during the sampling period (includes zeroes when a given taxonomic entity was absent in a given sampling event). It provides a detailed record of the abundances of the fish community through time in a frequent sampling regime (on average, sampling was done every 6 days). The dataset shows that the amount of fish from invasive taxa exceeds the count of fish from native taxa in the Minho Estuary.

Dataset of the complete mitogenome of the deep-sea sailfin roughshark, Oxynotus paradoxus Frade, 1929.

Chondrichthyans comprise a diverse group of vertebrate species with extraordinary ecological relevance. Yet, multiple members of this evolutionary lineage are associated with significant extinction risk. The sailfin roughshark Oxynotus paradoxus is a deep-water benthic shark currently listed as vulnerable due to population declines in parts of its range. Here we provide the first complete mitochondrial genome of O. paradoxus, comprising also the first record for the genus and family Oxynotidae. These data can facilitate future monitoring of the genetic diversity in this and related species. Genomic DNA was extracted from O. paradoxus collected in the eastern North Atlantic off western Portugal (37.59°N, 9.51°W) and sent for Illumina Paired-End (2 × 150 bp) library construction and whole genome sequencing on a Novaseq6000 platform. Trimmomatic (version 0.38) was used to remove adapters and MitoZ (version 3.4) to assemble and annotate the mitogenome. This mitogenome with 17 100 bp has a total of 38 genes, 13 of which are protein-coding genes, 23 transfer RNA genes, and 2 ribosomal RNA genes. Eight transfer RNAs and 1 protein-coding gene (NADH dehydrogenase subunit 6, NAD6) are in the complementary strand. In the provided phylogenetic inference, with all available and verified Squalomorphii mitogenomes, the four orders are well separated, and as expected, O. paradoxus is placed in the Squaliformes order. This data reinforces the need for more genomic resources for the Oxynotidae family.

The benthic food web connects the estuarine habitat mosaic to adjacent ecosystems.

Energy flows from land to sea and between pelagic and benthic environments have the potential to increase the connectivity between estuaries and adjacent ecosystems as well as among estuarine habitats. To identify such energy flows and the main trophic pathways of energy transfer in the Minho River estuary, we investigated the spatial and temporal fluctuations of carbon and nitrogen stable isotope ratios in benthic (and their potential food sources) and epibenthic consumers. Sampling was conducted along the estuarine salinity gradient from winter to summer of 2011. We found that the carbon (δ13C = 13C/12C) and nitrogen (δ15N = 15N/14N) stable isotope ratios of the most abundant benthic and epibenthic consumers varied along the salinity gradient. The δ13C values increased seaward, whereas the opposite pattern was found for the δ15N, especially during the summer. The stable isotope ratios revealed two trophic pathways in the Minho estuary food web. The first pathway is supported by phytoplankton and represented by filter feeders such as zooplankton and some deposit feeders, particularly amphipods and polychaetes. The second pathway is supported by detritus and composed essentially of deposit feeders, which by being consumed, allow detritus to be incorporated into higher trophic levels. Spatial and temporal feeding variations in the estuarine benthic food web are driven by hydrology and proximity to adjacent ecosystems (terrestrial, marine). During high river discharge periods, the δ13CPOC (ca. -28‰) and C: NPOM (>10) values suggested an increase of terrestrial-derived OM to the particulate OM pool, which was then used by suspension feeders. During low river discharge periods, marine intrusion increased upriver, which was reflected in benthic consumers' 13C-enriched stable isotope values. No relationship was found between food quality (phytoplankton vs. detritus) and food chain length because the lowest and highest values were associated with freshwater and saltmarsh areas, respectively, both dominated by the detrital pathway. This study demonstrates that benthic consumers enhance the connectivity between estuaries and its adjacent ecosystems by utilizing subsidies of terrestrial and marine origin and that benthic-pelagic coupling is an important energy transfer mechanism to the benthic food web.

A glimpse into the trophic ecology of deep-water sharks in an important crustacean fishing ground.

Deep-water sharks are among the most vulnerable deep-water taxa because of their extremely conservative life-history strategies (i.e., late maturation, slow growth, and reproductive rates), yet little is known about their biology and ecology. Thus, this study aimed at investigating the trophic ecology of five deep-water shark species, the birdbeak dogfish (Deania calcea), the arrowhead (D. profundorum), the smooth lanternshark (Etmopterus pusillus), the blackmouth catshark (Galeus melastomus) and the knifetooth dogfish (Scymnodon ringens) sampled onboard a crustacean bottom-trawler off the south-west coast of Portugal. We combined carbon and nitrogen stable isotopes with RNA and DNA (RD) ratios to investigate the main groups of prey assimilated by these species and their nutritional condition, respectively. Stable isotopes revealed overall small interspecific variability in the contribution of different taxonomic groups to sharks' tissues, as well as in the origin of their prey. S. ringens presented higher δ15 N and δ13 C values than the other species, suggesting reliance on bathyal cephalopods, crustaceans and teleosts; the remaining species likely assimilated bathy-mesopelagic prey. The RD ratios indicated that most of the individuals had an overall adequate nutritional condition and had recently eaten. This information, combined with the fact that stable isotopes indicate that sharks assimilated prey from the local or nearby food webs (including commercially important shrimps), suggests a potential overlap between this fishing area and their foraging grounds, which requires further attention.

Influence of climate change and extreme weather events on an estuarine fish community.

Extreme weather events are becoming more frequent as a result of climate change, and the increasing frequency of these events may lead to significant changes in fish assemblages. In this sense, this work aimed to study the effects of climate change and extreme weather events on fish assemblages in the Rio Minho estuary (Portugal). Between 2010 and 2019, continuous weekly sampling with fyke nets was carried out to assess the dynamics of fish assemblages in the estuary. In addition, temperature and precipitation data were obtained from satellite information to assess the relationship between climatic variables and fish composition, structure, and diversity. Fish populations changed significantly over time, becoming less diverse and largely dominated by a few, mostly invasive species (e.g., carp, goldfish, pumpkinseed, and tench), while the abundance of most native species declined over the years (e.g., panjorca, stickleback, and shad). High temperatures and low precipitation negatively affected native species, while the invasive species benefited from increased temperatures and extreme weather events (droughts and floods).

The complete mitochondrial genome of the endemic Iberian pygmy skate Neoraja iberica Stehmann, Séret, Costa, & Baro 2008 (Elasmobranchii, Rajidae).

Skates, Chondrichthyes fishes from order Rajiformes, are the most species-rich group of all Batoidea. However, their phylogenetic relationships and systematics is still a highly discussed and controversial subject. The use of complete mitogenome has shown to be a promising tool to fill this gap of knowledge. Here, the complete mitogenome of the Iberian pygmy skate Neoraja iberica (Stehmann, Séret, Costa & Baro 2008) was sequenced and assembled. The mitogenome is 16,723 bp long and its gene content (i.e. 13 protein-coding genes, 22 transfer RNA, and 2 ribosomal RNA genes) and arrangement are the expected for Batoidea. Phylogenetic reconstructions, including 89 Rajiformes and two outgroup Rhinopristiformes, recovered family Rajidae as monophyletic, and further divided in the monophyletic tribe Rajini, sister to tribes Amblyrajini and Rostrorajini. The newly sequenced N. iberica mitogenome is the first representative of the tribe Rostrorajini.

Habitat use and food sources of European flounder larvae (Platichthys flesus, L. 1758) across the Minho River estuary salinity gradient (NW Iberian Peninsula).

The European flounder (Platichthys flesus Linnaeus, 1758) exhibits plasticity for several life traits throughout its distribution range, including ontogenetic habitat shifts during early life, as well as the timing and duration of spawning. Estuaries are preferred as nursery habitat; however, the importance of specific salinity zones for larval development is not well-understood. Therefore, we aimed to identify the significance of distinct estuarine salinity habitats (i.e., tidal freshwater, brackish) along the Minho River estuary (NW-Iberian Peninsula, Europe) for larval development by combining field observations with carbon (C) and nitrogen (N) stable isotope analysis. Sampling occurred between January 2015 and January 2016 in six sampling stations across the estuarine salinity gradient. A total of 29 larvae were collected in the Minho River estuary from March till September 2015. Spawning likely occurred near the river mouth because the highest abundance of larvae occurred in the brackish estuary. Timing for migration towards freshwater was variable with metamorphosis likely occurring in both brackish and freshwater habitats. European flounder larvae obtained their diet from the benthic food web, indicating that benthic habitat is fundamental for larval development, including prior to settlement. This study provides further evidence on the behavioral plasticity of European flounder during early life regarding both habitat use and timing of migration towards freshwater habitats. Additionally, this study demonstrates the importance of preserving estuarine connectivity for this migratory species.

Benthic food webs support the production of sympatric flatfish larvae in estuarine nursery habitat.

Identifying nursery habitats is of paramount importance to define proper management and conservation strategies for flatfish species. Flatfish nursery studies usually report upon habitat occupation, but few attempted to quantify the importance of those habitats to larvae development. The reliance of two sympatric flatfish species larvae, the European flounder Platichthys flesus and the common sole Solea solea, on the estuarine food web (benthic vs. pelagic) was determined through carbon and nitrogen stable isotope analysis. The organic matter sources supporting the production of P. flesus and S. solea larvae biomass originates chiefly in the benthic food web. However, these species have significantly different δ13C and δ15N values which suggests that they prey on organisms that use a different mixture of sources or assimilate different components from similar OM pools (or both).

Implante dentário em incisivo central versus faceta dentária: trabalhando com diferentes substratos: passo a passo clínico / Dental implant in a central incisor versus ceramic veneers: working with different substrates: clinical step by step

No tratamento odontológico que almeje a estética é fundamental a realização de um planejamento clínico minucioso. Nesse contexto os implantes dentários unitários têm sido comumente empregados para a substituição de dentes perdidos. No entanto, a reabilitação de um dente/implante anterossuperior ainda é um desafio para os profissionais de odontologia. Este artigo tem por objetivo demonstrar o passo a passo de um caso clínico com implante dentário em um incisivo central, prótese sobre implante e facetas, com ênfase em uma solução clínica para igualar o substrato de uma coroa sobre implante com a cor de dentina de um dente preparado para faceta dentária, ressaltando a importância de restaurações estéticas em diferentes substratos...

A rigorous clinical planning is fundamental towards aesthetic treatments. In this context, single-unit dental implants has been commonly used to replace missing teeth. However, the rehabilitation of an anterior maxillary tooth/implant is still a challenge for dental professionals. This article aims to demonstrate the step by step of a clinical case with dental implant in a central incisor, implant-supported restorations and ceramic veneers, with emphasis on a clinical solution for matching the shade of an implant-supported crown and dentin shade of a tooth prepared for ceramic laminate, emphasizing the importance of aesthetic restorations on different substrates...