Planktonic Ctenophora of the Madeira archipelago (Northeastern Atlantic)

Ctenophores are fragile gelatinous organisms whose diversity and distribution are relatively unknown. For the first time, the occurrence of four planktonic species, namely Ocyropsis crystallina, Eurhamphaea vexilligera, Cestum veneris, and Beroe sp., was reported from Madeira archipelago waters (NE subtropical Atlantic). This report represents the northernmost records in the Eastern Atlantic Ocean for O. crystallina and E. vexilligera.

Lipid characterization of 14 macroalgal species from Madeira Archipelago: implications for animal and human nutrition

The lipid and fatty acid profiles of 14 marine macroalgal species from the Madeira Archipelago, including two green (Ulvales and Dasycladales), three red (Corallinales, Bonnemaisoniales, and Ceramiales) and nine brown (Fucales, Dictyotales, and Sphacelariales) species were characterised in order to determine their potential use for animal and human nutrition. The total lipid content of species analysed was generally low, varying from 0.2 to 5.2% of dry weight. All species presented an omega 6/omega 3 (n-6/n-3) ratio lower than 10, as recommended by the World Health Organization for proper human health. Polyunsaturated fatty acids (PUFA), including linoleic acid and alpha-linolenic acid were exceptionally high in the green macroalga Ulva sp. Red macroalgae were rich in n-3 long-chain PUFA, particularly Asparagopsis taxiformis, which contained 6.6% of docosahexaenoic acid, and Halopithys incurva with 9.3% of eicosapentaenoic acid. Within Ochrophyta, Dictyota dichotoma is an interesting source of n-3 PUFA due to its high stearidonic acid proportion (8.0%). In addition, H. incurva contained a high proportion of both mono- and digalactosyldiacylglycerols. According to their lipid profiles, most macroalgae analysed might be considered of particular interest for their potential exploitation for human nutrition and livestock and aquaculture production.

A New Signal of Tropicalization in the Northeast Atlantic: The Spread of the Spotfin Burrfish Chilomycterus reticulatus in Madeira Archipelago and Its Invasion Risk

Current trends in the global climate facilitate the displacement of numerous marine species from their native distribution ranges to higher latitudes when facing warming conditions. In this work, we analyzed occurrences of a circumtropical reef fish, the spotfin burrfish, Chilomycterus reticulatus (Linnaeus, 1958), in the Madeira Archipelago (NE Atlantic) between 1898 and 2021. In addition to available data sources, we performed an online survey to assess the distribution and presence of this species in the Madeira Archipelago, along with other relevant information, such as size class and year of the first sighting. In total, 28 valid participants responded to the online survey, georeferencing 119 C. reticulatus sightings and confirming its presence in all archipelago islands. The invasiveness of the species was screened using the Aquatic Species Invasiveness Screening Kit. Five assessments rated the fish as being of medium risk of establishing a local population and becoming invasive. Current temperature trends might have facilitated multiple sightings of this thermophilic species in the Madeira Archipelago. The present study indicates an increase in C. reticulatus sightings in the region. This underlines the need for updated comprehensive information on species diversity and distribution to support informed management and decisions. The spread of yet another thermophilic species in Madeiran waters provides further evidence of an ongoing tropicalization, emphasizing the need for monitoring programs and the potential of citizen science in complementing such programs.

Sharks, rays and chimaeras of the Seine and Unicorn seamounts (NE Atlantic Ocean)

Background Seamounts are underwater mountains which typically rise rather steeply at least several hundred meters above the deep-sea floor. These geological features interrupt water flow and hence may induce changes in the circulation of different water masses, in turn causing different physical and biological effects. For this reason, seamounts are biodiversity hotspots, housing a wide number of species, as is with the case of the Seine and Unicorn seamounts, which are a part of the Madeira-Tore seamount chain located between Portugal mainland, southwestern Europe and Madeira archipelago (NE Atlantic). Methods Fisheries independent surveys allowed the collection of Chondrichthyes specimens from the Seine and Unicorn seamounts. Individuals were caught over the course of two research cruises, first in 2004 and later in 2017, with species distribution ranging from the summit down to 2500 m of depth. Results Fifteen species belonging to 7 different taxonomical families were collected in the two surveyed areas. Two species were recorded for the first time and added to the checklist of the Seine seamount (Centrophorus granulosus and Somniosus rostratus), and three species for the Unicorn seamount (C. granulosus, Centroscymnus coelolepis and Centroselachus crepidater). Distribution and frequency of occurrence for the collected species were evaluated in relation to depth. Conclusions This work is a valuable contribution to the knowledge of seamount-associated fish fauna. Moreover, the checklist of sharks, rays and chimaeras was updated for the Seine and Unicorn seamounts, summing up 20 species.

Morphological and genetic data suggest a complex pattern of inter-island colonisation and differentiation for mining bees (Hymenoptera: Anthophila: Andrena) on the Macaronesian Islands

Oceanic islands have long been considered engines of differentiation and speciation for terrestrial organisms. Here we investigated colonisation and radiation processes in the Madeira Archipelago and the Canary Islands of the Andrena wollastoni group of bees (subgenus Micrandrena), which comprises six endemic species and five endemic subspecies on the islands. Mitochondrial COI sequences support the monophyly of the four species of the Canary Islands and the two species of the Madeira Archipelago and suggest a relatively young age for all taxa. The data do not support a simple stepping-stone model (eastern-western colonisation from the mainland, with splitting into new taxa), but suggest Andrena gomerensis (extant on La Gomera and La Palma) or its ancestor as the basal lineage from which all other taxa evolved. Andrena lineolata (Tene-rife) or its putative ancestor (A. gomerensis) is sister to A. dourada (Porto Santo), A. catula (Gran Canaria), and A. acuta (also Tenerife). Andrena dourada (Porto Santo) and A. wollastoni (Madeira Island) are sister species. Morphologically and morphometrically defined subspecies were not distinguishable with COI DNA sequences. Colonisation likely led from the Canary Islands to the Madeira Archipelago and not from the mainland directly to the latter.

Complete Genome Sequence of Two Deep-Sea Streptomyces Isolates from Madeira Archipelago and Evaluation of Their Biosynthetic Potential

The deep-sea constitutes a true unexplored frontier and a potential source of innovative drug scaffolds. Here, we present the genome sequence of two novel marine actinobacterial strains, MA3_2.13 and S07_1.15, isolated from deep-sea samples (sediments and sponge) and collected at Madeira archipelago (NE Atlantic Ocean; Portugal). The de novo assembly of both genomes was achieved using a hybrid strategy that combines short-reads (Illumina) and long-reads (PacBio) sequencing data. Phylogenetic analyses showed that strain MA3_2.13 is a new species of the Streptomyces genus, whereas strain S07_1.15 is closely related to the type strain of Streptomyces xinghaiensis. In silico analysis revealed that the total length of predicted biosynthetic gene clusters (BGCs) accounted for a high percentage of the MA3_2.13 genome, with several potential new metabolites identified. Strain S07_1.15 had, with a few exceptions, a predicted metabolic profile similar to S. xinghaiensis. In this work, we implemented a straightforward approach for generating high-quality genomes of new bacterial isolates and analyse in silico their potential to produce novel NPs. The inclusion of these in silico dereplication steps allows to minimize the rediscovery rates of traditional natural products screening methodologies and expedite the drug discovery process.

New taxa to the flora of Madeira archipelago islands (Portugal)

73 new references for 72 taxa of vascular plant are here reported for the Madeira archipelago. 55 not previously recorded for Desertas Islands, 12 to Porto Santo Island and 6 for Madeira Island. Of the 72 taxa, 28 are xenophytes, and 10 are new taxa to the flora of the archipelago (of these 9 are xenophytes). Their native status, taxonomy and distribution are briefly discussed.

Analysis of Big Game Fishing Catches of Blue Marlin (Makaira nigricans) in the Madeira Archipelago (Eastern Atlantic) and Factors that Affect Its Presence

The archipelago of Madeira (Portugal) is one of the main European big game fishing locations, where the main target species is the blue marlin (Makaira nigricans). Catch data for these fish were used to analyze their presence over the years, estimate their average weights, and calculate annual fishing success rates. The results showed a marked seasonal effect, with higher average catch rates in summer (June–July), suggesting a migration from the equatorial waters they inhabit at the beginning of the year to northern areas when the waters become warmer. The influences of some environmental factors were analyzed using generalized additive models, and it was observed that the occurrence of blue marlin may be influenced by water temperature, wind, rain, and atmospheric pressure. This fishery did not register a high mortality rate in blue marlin specimens due to the usual practice of catch and release; individuals captured in this fishery can be used as a source of information that allows for follow-up on the status of the blue marlin population in the region.