Earthquake, floods and changing land use history: A 200-year overview of environmental changes in Selenga River basin as indicated by n-alkanes and related proxies in sediments from shallow lakes.

The Selenga River basin, located in southern Siberia, is an important component of the Lake Baikal ecosystem, and comprises approximately 80 % of the Baikal watershed. Within the Selenga River basin, two localized study regions were chosen. The first, the Selenga Delta, is one of the largest inland freshwater floodplains in the world and plays an important role in the ecosystem functioning of Baikal.

The Fundão dam failure: Iron ore tailing impact on marine benthic macrofauna.

The Fundão dam failure, the worst environmental disaster in Brazilian history, launched 50 million m of iron ore tailings mud through the Doce River, reaching the Atlantic Ocean. Generally, mine tailings increase the sediment inflow, leading to mud burial of epibenthic macrofauna, and the raise of metal(oid)s concentration causing macrofauna long-term changes. After almost four years, tailings mud was still spreading on the Doce River Shelf, while impacts on marine macrofauna were still unknown.

Finding Aquaporins in Annelids: An Evolutionary Analysis and a Case Study.

Aquaporins (AQPs) are a family of membrane channels facilitating diffusion of water and small solutes into and out of cells. Despite their biological relevance in osmoregulation and ubiquitous distribution throughout metazoans, the presence of AQPs in annelids has been poorly investigated. Here, we searched and annotated sequences in public genomes and transcriptomes of annelids, inferred their evolutionary relationships through phylogenetic analyses and discussed their putative physiological relevance.

A meta-analytic review of fish antioxidant defense and biotransformation systems following pesticide exposure.

Pesticides reach aquatic ecosystems and interact with various targets in cells of fish and other living organisms. Toxicity originates during the metabolization process, which may produce toxic metabolites or reactive oxygen species (ROS). Ethoxyresorufin-O-deethylase (EROD), glutathione S-transferase (GST), catalase (CAT), superoxide dismutase (SOD) activities, and levels of reduced glutathione (GSH) indicate toxicants interacted with drug-metabolizing and antioxidant systems, i.

Revisiting kinorhynch segmentation: variation of segmental patterns in the nervous system of three aberrant species.

Background: Kinorhynch segmentation differs from the patterns found in Chordata, Arthropoda and Annelida which have coeloms and circulatory systems. Due to these differences and their obsolete status as 'Aschelminthes', the microscopic kinorhynchs are often not acknowledged as segmented bilaterians. Yet, morphological studies have shown a conserved segmental arrangement of ectodermal and mesodermal organ systems with spatial correspondence along the anterior-posterior axis.

Geographical sampling bias on the assessment of endemism areas for marine meiobenthic fauna.

Species distribution patterns are constrained by historical and ecological processes in space and time, but very often the species range sizes are geographical sampling biases resulting from unequal sampling effort. One of the most common definitions of endemism is based on the "congruence of distributional areas" criterion, when two or more species have the same distributional limits. By acknowledging that available data of marine meiobenthic species are prone to geographical sampling bias and that can affect the accuracy of the biogeographical signals, the present study combines analyses of inventory incompleteness and recognition of spatial congruence of Gastrotricha, Kinorhyncha, meiobenthic Annelida and Tardigrada in order to better understand the large-scale distribution of these organisms in coastal and shelf areas of the world.

Daily environmental variation influences temporal patterns of marine debris deposition along an estuarine outlet in southern Brazil.

The influence of short-term (daily) variation in environmental conditions (rainfall, wind, tide, river flow) on debris accumulation was examined on two beaches at an estuarine outlet. Sampling occurred over 60 consecutive days along two sections (Internal Area, IA; and External Area, EA) of the Paranaguá Estuary Complex's southern outlet, in Paraná, southern Brazil. The IA is sheltered from direct wave action, whereas the EA is more exposed to wave and wind action from the open ocean.

Pesticide effects on fish cholinesterase variability and mean activity: A meta-analytic review.

Fish cholinesterases (ChEs) - like acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) - are common biomarkers of environmental contamination due to their sensitivity to a variety of toxicants. To understand pesticide effects on fish ChEs mean activity and variability, we conducted a systematic review and meta-analyses. Our goal was to verify (i) if brain and muscle ChEs responded differently to pesticide exposure; (ii) how fish size and life stage (i.

Life-history traits of : Reproduction, development, and larval competence.

The sun coral Lesson, 1829 (Dendrophylliidae) is a widely distributed shallow-water scleractinian that has extended its range to non-native habitats in recent decades. With its rapid spread, this coral is now one of the main invasive species in Brazil. Its high invasive capability is related to opportunistic characteristics, including several reproductive strategies that have allowed it to disperse rapidly and widely.

Atlantic West Ophiothrix spp. in the scope of integrative taxonomy: Confirming the existence of Ophiothrix trindadensis Tommasi, 1970.

We re-describe and confirm the validity of Ophiothrix trindadensis Tommasi, 1970 (Echinodermata: Ophiuroidea). This is a native species from Brazil, however it lacked a type series deposited in scientific collections. The recognition of O.

Erratum: Author Correction: Biodiversity estimates and ecological interpretations of meiofaunal communities are biased by the taxonomic approach.

[This corrects the article DOI: 10.1038/s42003-018-0119-2.].

Biodiversity estimates and ecological interpretations of meiofaunal communities are biased by the taxonomic approach.

Accurate assessments of biodiversity are crucial to advising ecosystem-monitoring programs and understanding ecosystem function. Nevertheless, a standard operating procedure to assess biodiversity accurately and consistently has not been established. This is especially true for meiofauna, a diverse community (>20 phyla) of small benthic invertebrates that have fundamental ecological roles.

Organic contamination as a driver of structural changes of hydroid's assemblages of the coral reefs near to Havana Harbour, Cuba.

Hydroid assemblage's responses to organic contamination were evaluated using sedimentary sterols as explanatory variables. At seven coral reef sites in the Havana west coast, hydroids were collected along three 10 m × 1 m, 10 m deep transects. Five sterols were analysed, i.

Biomarker responses in fish exposed to polycyclic aromatic hydrocarbons (PAHs): Systematic review and meta-analysis.

Biomarkers of antioxidant and biotransformation systems are commonly used to assess polycyclic aromatic hydrocarbons (PAHs) pollution in fish. Despite their extensive application of biomarkers, contradictory results are vastly reported in the literature, even for the same species in similar contamination scenarios. This study aims to verify response patterns of biomarkers in fish exposed to PAHs.

The use of metabarcoding for meiofauna ecological patterns assessment.

Marine meiofauna comprises up to 22 phyla. Its morphological identification requires time and taxonomists' expertise, and molecular tools can make this task faster. We aim to disentangle meiofaunal diversity patterns at Araçá Bay by applying a model selection approach and estimating the effectiveness of metabarcoding (18S rDNA) and morphological methods for estimating the response of meiofauna diversity in small-scale interactions with environmental variables.

Shallow-water brittle stars (Echinodermata: Ophiuroidea) from Araçá Bay (Southeastern Brazil), with spatial distribution considerations.

The detailed study of arm ossicles, particularly the lateral arm plates, is providing valuable information in the elucidation of ophiuroid taxonomy. The present study describes in detail 16 species of brittle stars from Araçá Bay, Brazil. This information is used to construct the first interactive electronic key, providing a valuable resource for a broad range of researchers.

Unraveling the performance of the benthic index AMBI in a subtropical bay: The effects of data transformations and exclusion of low-reliability sites.

We investigated the relationship between the AMBI index and different contamination proxies in an urbanized bay in South America (SE Brazil), and the effect of (a) abundance data transformation and (b) exclusion of low-reliability sites (high SD; low N) on the index' performance. Poor ecological quality and opportunistic species were related to an increase in contaminants concentrations and mud content. Good ecological status and sensitive species (EG I) were mainly related to increased hydrodynamics.

Demystifying the Capitella capitata complex (Annelida, Capitellidae) diversity by morphological and molecular data along the Brazilian coast.

The sibling species of Capitella capitata are globally known for their tolerance to disturbed habitats and the C. capitata complex is often used as an ecological indicator. A recent re-description proposed that C.

Phylogeny and biogeography of the scaleless scale worm (Sigalionidae, Annelida).

is a scaleless group of small scale worms inhabiting sandy bottoms in shallow marine waters. This group was once considered rare, but now 45 described species can be characterized, among others, by their paired, segmental copulatory organs (one to multiple external pairs), which display a complexity of various accessory structures. The evolutionary significance of these unique organs was suggested in the late 1960s, but has been heavily debated since the late 1990s and remains controversial.

In situ ingestion of microfibres by meiofauna from sandy beaches.

Microfibres are widespread contaminants in marine environments across the globe. Detecting in situ ingestion of microfibres by small marine organisms is necessary to understand their potential accumulation in marine food webs and their role in marine pollution. We have examined the gut contents of meiofauna from six sandy beaches in the Atlantic Ocean and the Mediterranean.

Phylogeny and systematics of Protodrilidae (Annelida) inferred with total evidence analyses.

Protodrilidae is a group of small, superficially simple-looking annelids, lacking chaetae and appendages, except for two prostomial palps. Originally considered to be one of the primitive "archiannelid" families, its affinity within Annelida is still highly debated. Protodrilids are found worldwide in the interstices of intertidal and subtidal marine sediments.