A new tetramic acid glycoside, aurantoside L (), was isolated from the sponge collected at Tsushima Is., Nagasaki Prefecture, Japan. The structure of aurantoside L () composed of a tetramic acid bearing a chlorinated polyene system and a trisaccharide part was elucidated using spectral analysis.
View Article and Find Full Text PDFTropical coastal benthic communities will change in species composition and relative dominance due to global (e.g., increasing water temperature) and local (e.
View Article and Find Full Text PDFThe relative influence of geography, currents, and environment on gene flow within sessile marine species remains an open question. Detecting subtle genetic differentiation at small scales is challenging in benthic populations due to large effective population sizes, general lack of resolution in genetic markers, and because barriers to dispersal often remain elusive. Marine lakes can circumvent confounding factors by providing discrete and replicated ecosystems.
View Article and Find Full Text PDFLarge grazers (megaherbivores) have a profound impact on ecosystem functioning. However, how ecosystem multifunctionality is affected by changes in megaherbivore populations remains poorly understood. Understanding the total impact on ecosystem multifunctionality requires an integrative ecosystem approach, which is especially challenging to obtain in marine systems.
View Article and Find Full Text PDFIn this study, we used 16S rRNA gene amplicon sequencing to investigate prokaryotic community composition of the Caribbean sponges Xestospongia muta and Agelas sventres from three depth ranges: < 30 m (shallow), 30-60 m (upper mesophotic), and 60-90 m (lower mesophotic). The prokaryotic community in shallow samples of X. muta was enriched in Cyanobacteria, Chloroflexota, and Crenarchaeota compared to samples from mesophotic depths, while mesophotic samples of X.
View Article and Find Full Text PDFMarine sponges (phylum Porifera) are leading organisms for the discovery of bioactive compounds from nature. Their often rich and species-specific microbiota is hypothesised to be producing many of these compounds. Yet, environmental influences on the sponge-associated microbiota and bioactive compound production remain elusive.
View Article and Find Full Text PDFPleistocene environmental changes are generally assumed to have dramatically affected species' demography via changes in habitat availability, but this is challenging to investigate due to our limited knowledge of how Pleistocene ecosystems changed through time. Here, we tracked changes in shallow marine habitat availability resulting from Pleistocene sea level fluctuations throughout the last glacial cycle (120-14 thousand years ago; kya) and assessed correlations with past changes in genetic diversity inferred from genome-wide SNPs, obtained via ddRAD sequencing, in Caribbean hawksbill turtles, which feed in coral reefs commonly found in shallow tropical waters. We found sea level regression resulted in an average 75% reduction in shallow marine habitat availability during the last glacial cycle.
View Article and Find Full Text PDFThe diversification of a host lineage can be influenced by both the external environment and its assemblage of microbes. Here, we use a young lineage of spiders, distributed along a chronologically arranged series of volcanic mountains, to investigate how their associated microbial communities have changed as the spiders colonized new locations. Using the stick spider Ariamnes waikula (Araneae, Theridiidae) on the island of Hawai'i, and outgroup taxa on older islands, we tested whether each component of the "holobiont" (spider hosts, intracellular endosymbionts and gut microbial communities) showed correlated signatures of diversity due to sequential colonization from older to younger volcanoes.
View Article and Find Full Text PDFHeredity (Edinb)
December 2021
The occasional westward transport of warm water of the Agulhas Current, "Agulhas leakage", around southern Africa has been suggested to facilitate tropical marine connectivity between the Atlantic and Indian oceans, but the "Agulhas leakage" hypothesis does not explain the signatures of eastward gene flow observed in many tropical marine fauna. We investigated an alternative hypothesis: the establishment of a warm-water corridor during comparatively warm interglacial periods. The "warm-water corridor" hypothesis was investigated by studying the population genomic structure of Atlantic and Southwest Indian Ocean green turtles (N = 27) using 12,035 genome-wide single nucleotide polymorphisms (SNPs) obtained via ddRAD sequencing.
View Article and Find Full Text PDFPost-translational modifications on histones can be stable epigenetic marks or transient signals that can occur in response to internal and external stimuli. Levels of histone modifications fluctuate during the cell cycle and vary among different cell types. Here, we describe a simple system to monitor the levels of multiple histone modifications in single cells by multicolor immunofluorescence using directly labeled modification-specific antibodies.
View Article and Find Full Text PDFPeripheral marine ecosystems can harbor endemic diversity and attract tourism attention, yet are generally not included in conservation management plans due to their remoteness or inland positioning. A case study in Raja Ampat of seven landlocked marine lakes containing golden jellyfish (Mastigias spp.) was conducted to address the lack of fundamental insights into evolutionary, ecological and social contexts of these ecosystems.
View Article and Find Full Text PDFRecent papers have suggested that epifaunal organisms use artificial structures as stepping-stones to spread to areas that are too distant to reach in a single generation. With thousands of artificial structures present in the North Sea, we test the hypothesis that these structures are connected by water currents and act as an interconnected reef. Population genetic structure of the blue mussel, Mytilus edulis, was expected to follow a pattern predicted by a particle tracking model (PTM).
View Article and Find Full Text PDFSponge-associated bacteria have been mostly cultured from shallow water (≤30 m) sponges, whereas only few studies targeted specimens from below 30 m. This study assessed the cultivability of bacteria from two marine sponges and collected from shallow (<30 m), upper mesophotic (30-60 m), and lower mesophotic (60-90 m) reefs. Sponge-associated bacteria were cultivated on six different media, and replicate plates were used to pick individual colonies or to recover the entire biomass.
View Article and Find Full Text PDFIncreasing incubation temperatures may threaten the viability of sea turtle populations. We explored opportunities for decreasing incubation temperatures at a Caribbean rookery with extreme female-biased hatchling production. To investigate the effect of artificial shading, temperatures were measured under simple materials (white sheet, white sand, palm leaves).
View Article and Find Full Text PDF(Selenka, 1867) and (Carter, 1886) occur in a broad range of marine environments and are allegedly widely distributed species in the Indo-Pacific. We coin the term 'moon sponges' for these species as they are spherical in shape with numerous porocalices resembling the lunar surface. Both species have a complex taxonomic history with high synonymization, in particular by Burton (1934, 1959).
View Article and Find Full Text PDFA collection of shrimp from deep reefs in the Dutch Caribbean is described. Most material originates from the Bonaire deep reef expedition (2013) by Wageningen Marine Research of Wageningen University. Some additional material was available from dives on Curaçao (2014).
View Article and Find Full Text PDFStriking genetic structure among marine populations at small spatial scales is becoming evident with extensive molecular studies. Such observations suggest isolation at small scales may play an important role in forming patterns of genetic diversity within species. Isolation-by-distance, isolation-by-environment and historical priority effects are umbrella terms for a suite of processes that underlie genetic structure, but their relative importance at different spatial and temporal scales remains elusive.
View Article and Find Full Text PDFBackground: Mitochondrial introns intermit coding regions of genes and feature characteristic secondary structures and splicing mechanisms. In metazoans, mitochondrial introns have only been detected in sponges, cnidarians, placozoans and one annelid species. Within demosponges, group I and group II introns are present in six families.
View Article and Find Full Text PDFMarine lakes, with populations in landlocked seawater and clearly delineated contours, have the potential to provide a unique model to study early stages of evolution in coastal marine taxa. Here we ask whether populations of the mussel from marine lakes in Berau, East Kalimantan (Indonesia) are isolated from each other and from the coastal mangrove systems. We analyzed sequence data of one mitochondrial marker (Cytochrome Oxidase I (COI)), and two nuclear markers (18S and 28S).
View Article and Find Full Text PDFPLoS One
July 2017
Saba Bank, a submerged atoll in the Caribbean Sea with an area of 2,200 km2, has attained international conservation status due to the rich diversity of species that reside on the bank. In order to assess the role of Saba Bank as a potential reservoir of diversity for the surrounding reefs, we examined the population genetic structure, abundance and health status of two prominent benthic species, the coral Montastraea cavernosa and the sponge Xestospongia muta. Sequence data were collected from 34 colonies of M.
View Article and Find Full Text PDFIn the present study, we compared communities of bacteria in two jellyfish species (the 'golden' jellyfish Mastigias cf.papua and the box jellyfish Tripedalia cf.cystophora) and water in three marine lakes located in the Berau region of northeastern Borneo, Indonesia.
View Article and Find Full Text PDFTropical mountains are hot spots of biodiversity and endemism, but the evolutionary origins of their unique biotas are poorly understood. In varying degrees, local and regional extinction, long-distance colonization, and local recruitment may all contribute to the exceptional character of these communities. Also, it is debated whether mountain endemics mostly originate from local lowland taxa, or from lineages that reach the mountain by long-range dispersal from cool localities elsewhere.
View Article and Find Full Text PDFIn the present study, we sampled bacterial communities associated with mussels inhabiting two distinct coastal marine ecosystems in Kalimantan, Indonesia, namely, marine lakes and coastal mangroves. We used 16S rRNA gene pyrosequencing and predicted metagenomic analysis to compare microbial composition and function. Marine lakes are small landlocked bodies of seawater isolated to varying degrees from the open sea environment.
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