The correct identification of the species going under the name Scizymenia dubyi (Schizymeniaceae, Rhodophyta) in the Azores, based on molecular and morphological evidences.

The 62nd Annual Meeting of the Phycological Society of America. New Orleans, Louisiana, EUA, 27-30 de Julho de 2008

Phylogenomic assessment prompts recognition of the Serianthes clade and confirms the monophyly of Serianthes and its relationship with Falcataria and Wallaceodendron in the wider ingoid clade (Leguminosae, Caesalpinioideae)

The Indo-Pacific legume genus Serianthes was recently placed in the Archidendron clade (sensu Koenen et al. 2020), a subclade of the mimosoid clade in subfamily Caesalpinioideae, which also includes Acacia, Archidendron, Archidendropsis, Falcataria, Pararchidendron, Paraserianthes and Wallaceodendron. Serianthes comprises ca. 18 species, five subspecies and two varieties that are characterised by bipinnately compound leaves with alternate sessile leaflets, branched axillary corymbiform panicles and woody indehiscent pods. Generic relationships, as well as species relationships within genera in the Archidendron clade, remain uncertain. While the sister relationship between Serianthes and the genus Falcataria is strongly supported by molecular data, the distinction between Serianthes and the monotypic genus Wallaceodendron has been questioned, based on their similar flower and fruit morphologies. We combined three gene-enriched hybrid capture DNA sequence datasets (generated from the 964 mimobaits v1 probe set, the expanded 997 mimobaits v2 probe set and the GoFlag angiosperm 408 probe set) and used their overlapping markers (77 loci of the target exonic and flanking regions) to test the monophyly of Serianthes and to investigate generic relationships within the Archidendron clade using 55 ingoid plus two outgroup taxa. We show that Serianthes is monophyletic, confirm the Serianthes + Falcataria sister relationship to Wallaceodendron and recognise this combined clade as the Serianthes clade within the Archidendron clade. We also evaluated the use of overlapping loci across datasets in combination with concordance analyses to test generic relationships and further investigate previously unresolved relationships across the wider ingoid clade. Concordance analysis revealed limited gene tree conflicts near the tips of the Archidendron clade, but increased discordance at the base of the clade, which could be attributed to rapid lineage divergence (radiation) and/or incomplete lineage sorting

Small tropical islands as hotspots of crustose calcifying red algal diversity and endemism

In the tropics, crustose calcifying red algae (Corallinophycidae and Peyssonneliales; CCRA) are dominant and important reef builders that serve a suite of ecological functions affecting reef health. However, CCRA taxa have historically been overlooked in floristic and ecological studies because of their high degrees of phenotypic plasticity and morphological convergence that impede reliable identifications based on morphology. This study provides an update of the CCRA diversity of Guam (Mariana Islands) based on a recent DNA barcoding effort. This account of CCRA taxa is compared to (1) the most current species inventories for Guam based on morphological identifications and (2) similar floristic accounts of CCRA from other regions using DNA barcoding. 492 CCRA specimens were collected from Guam for which two markers, COI-5P and psbA, were used for phylogenetic analysis and species delimitation. Phylogenetic relationships were inferred using maximum likelihood. Species richness estimates were obtained through a conservative approach using the Automatic Barcode Gap Discovery method for species delimitation. A total of 154 putative CCRA species were identified, with 106 representatives of the subclass Corallinophycidae and 48 belonging to the order Peyssonneliales. When compared to previous studies based on morphological identification, molecular data suggests that all but one of the CCRA species reported for Guam were incorrectly identified and CCRA species richness is more than six times higher than previously assumed. Species accumulation curves show that CCRA species richness will continue to rise with increased sampling effort and the exploration of new (micro)habitats before reaching a plateau. Guam’s true CCRA richness might eventually exceed the currently reported species richness of all marine red algae for the island. Of the 154 putative species documented in this study, only ten closely match (≥ 98% COI-5P sequence similarity) previously described species, implying that many are probably new species to science. The here-reported CCRA diversity for Guam as a small, remote tropical island in the Western Pacific Ocean is greater than those of well-documented CCRA floras for much larger nearshore ecosystems in Brazil and New Zealand, emphasizing the value of tropical islands as hotspots of marine biodiversity

First detection of critically endangered scalloped hammerhead sharks (Sphyrna lewini) in Guam, Micronesia, in five decades using environmental DNA

Among the hammerhead sharks, scalloped hammerheads (Sphyrna lewini) have undergone the steepest population declines worldwide. Due to their high susceptibility to exploitation, the species is now classified as ‘critically endangered’, the most threatened category listed by the International Union for Conservation of Nature. There is an urgent need for data on the distribution of S. lewini to inform the design and implementation of effective conservation management strategies, and mitigate the risk of global extinction. Environmental DNA (eDNA) is emerging as a powerful method to monitor the geographic distribution, population trends, and habitat usage of rare and endangered species. In comparison to traditional survey methods, eDNA methods offer lower cost, higher detection rates, and are non-invasive. At present, there is no targeted eDNA assay for the detection of S. lewini and existing methods to assess their distribution are either fisheries-dependent, leading to bias, or costly and laborious, leading to impracticality in regions of low or unknown abundance. Here we present an optimised workflow for the detection of S. lewini presence using eDNA methods, and apply these to successfully detect scalloped hammerhead sharks in Guam, of the western Pacific Ocean, where their presence has not been scientifically reported since the 1970s. The detection of S. lewini by eDNA survey methods was achieved from a single-day sampling effort, demonstrating the efficacy of the technique and workflow. If implemented, the eDNA survey methods developed here will enable the rapid generation of information on the distribution of scalloped hammerhead sharks in the western Pacific, and likely globally, and assist in the accurate placement of no-take reserves to best enable the species’ recovery

Permanent grasslands in Europe : Land use change and intensification decrease their multifunctionality

Acknowledgments We acknowledge the financial support of this work by European Union Horizon 2020 research and innovation programme, under grant agreement 774124, project SUPER-G (Developing Sustainable Permanent Grassland Systems and Policies).Peer reviewedPublisher PD

Development of Gene Expression Markers of Acute Heat-Light Stress in Reef-Building Corals of the Genus Porites

Coral reefs are declining worldwide due to increased incidence of climate-induced coral bleaching, which will have widespread biodiversity and economic impacts. A simple method to measure the sub-bleaching level of heat-light stress experienced by corals would greatly inform reef management practices by making it possible to assess the distribution of bleaching risks among individual reef sites. Gene expression analysis based on quantitative PCR (qPCR) can be used as a diagnostic tool to determine coral condition in situ. We evaluated the expression of 13 candidate genes during heat-light stress in a common Caribbean coral Porites astreoides, and observed strong and consistent changes in gene expression in two independent experiments. Furthermore, we found that the apparent return to baseline expression levels during a recovery phase was rapid, despite visible signs of colony bleaching. We show that the response to acute heat-light stress in P. astreoides can be monitored by measuring the difference in expression of only two genes: Hsp16 and actin. We demonstrate that this assay discriminates between corals sampled from two field sites experiencing different temperatures. We also show that the assay is applicable to an Indo-Pacific congener, P. lobata, and therefore could potentially be used to diagnose acute heat-light stress on coral reefs worldwide

Episodic eruptions of volcanic ash trigger a reversible cascade of nuisance species outbreaks in pristine coral habitats.

Volcanically active islands abound in the tropical Pacific and harbor complex coral communities. Whereas lava streams and deep ash deposits are well-known to devastate coral communities through burial and smothering, little is known about the effect of moderate amounts of small particulate ash deposits on reef communities. Volcanic ash contains a diversity of chemical compounds that can induce nutrient enrichments triggering changes in benthic composition. Two independently collected data sets on the marine benthos of the pristine and remote reefs around Pagan Island, Northern Mariana Islands, reveal a sudden critical transition to cyanobacteria-dominated communities in 2009-2010, which coincides with a period of continuous volcanic ash eruptions. Concurrently, localized outbreaks of the coral-killing cyanobacteriosponge Terpios hoshinota displayed a remarkable symbiosis with filamentous cyanobacteria, which supported the rapid overgrowth of massive coral colonies and allowed the sponge to colonize substrate types from which it has not been documented before. The chemical composition of tephra from Pagan indicates that the outbreak of nuisance species on its reefs might represent an early succession stage of iron enrichment (a.k.a. "black reefs") similar to that caused by anthropogenic debris like ship wrecks or natural events like particulate deposition from wildfire smoke plumes or desert dust storms. Once Pagan's volcanic activity ceased in 2011, the cyanobacterial bloom disappeared. Another group of well-known nuisance algae in the tropical Pacific, the pelagophytes, did not reach bloom densities during this period of ash eruptions but new species records for the Northern Mariana Islands were documented. These field observations indicate that the study of population dynamics of pristine coral communities can advance our understanding of the resilience of tropical reef systems to natural and anthropogenic disturbances

Branching <i>Lithophyllum</i> Coralline Algae: Dominant Reef Builders on Herbivory-Depressed Tropical Reefs after High Coral Mortality

A unique shift in benthic community composition, where scleractinian corals are replaced by coralline algae, has been observed on coral reefs in Guam in the western Pacific. Guam’s reefs have been subjected to intense fishing pressure and impaired water quality for decades. Since 2013, heat stress has emerged as an additional major threat to the island’s coral reefs. After a severe coral bleaching and mortality event in 2017, branching coralline algae of the genus Lithophyllum rapidly overgrew dead coral skeletons of the ecosystem engineer Acropora abrotanoides and have since become major components of forereef communities over a broad depth range. By now, the persistence of increased Lithophyllum cover meets the temporal criterium of phase shifts, but accurate estimates on the degree of dominance over appropriate spatial scales are lacking due to the absence of reliable baseline data. The ecological impacts of coral reef transitions towards increased coralline cover are unclear. Whereas carbonate budgets and reef growth could remain positive in the long term, the downstream effect of changes in structural complexity, (micro)habitat diversity, and benthic community composition on ecological processes and reef-associated faunal assemblages is unknown

<i>Terpios</i> and associated cyanobacteria overgrowing corals, macroalgae, and bare reef substrates.

<p>A,B. <i>Terpios</i> overgrowing some of the largest <i>Porites</i> colonies found in Pagan. C,D. Vigorous outgrowths of filamentous cyanobacteria at the coral-facing margin of the sponge. E,F. Fleshy macroalgae [<i>Gracilaria salicornia</i> (C. Agardh) E.Y. Dawson], calcified green algae (<i>Halimeda</i> spp.), and geniculate coralline algae (<i>Amphiroa</i> and <i>Jania</i> spp.) overgrown by <i>Terpios</i>. G. <i>Terpios</i> outbreak covering large areas of otherwise turf or biofilm covered boulders. H. Close-up of <i>Terpios</i> overgrowing boulders with tufts of filamentous cyanobacteria emerging from the sponge surface.</p