Search Results (99)

This paper provides a comprehensive review of sessile benthic invertebrate biodiversity across three interconnected marine areas in Western Australia’s Gascoyne and southern Pilbara regions: Ningaloo Reef (a UNESCO World Heritage site), the nearby Muiron Islands to its north, and Exmouth Gulf to its east. The study aims to identify taxonomic and spatial knowledge gaps and establish a baseline biodiversity record for the broader region. We collated specimen-based records from seven Australian museums and supplemented them with data from the Atlas of Living Australia, iNaturalist, and a Web of Science literature review. In total, we report 827 verified species of sessile benthic invertebrates in shallow waters (less than 30 m depth) across the Gascoyne and southern Pilbara regions from 4578 records. Ningaloo Reef exhibits the highest diversity, hosting 587 species, including 239 scleractinian corals and 124 sponges. Exmouth Gulf is home to a diverse and unique assemblage of at least 295 species, including 165 species of putative turbid water specialists or regionally restricted species which are not found at Ningaloo Reef or the Muiron Islands. Notably, all three sea pen species identified in this review are recorded exclusively from Exmouth Gulf. The Gulf also hosts a distinctive community of filter-feeding invertebrates, including 125 sponges, 27 tunicates, and 18 anemones that are not found in neighboring regions. The Muiron Islands, although under sampled, host 22 species of sponges, 14 octocorals, and 5 tunicates that have not so far been found at Ningaloo Reef or Exmouth Gulf, highlighting the uniqueness of the islands’ marine invertebrate fauna. The southern sector of Ningaloo Reef is under sampled, and there are gaps in the state faunal collections for many groups, including anemones, corallimorphs, zoanthids, cerianthids, and hydrozoans. Further targeted taxonomic research on existing museum collections is crucial, as only 18% of specimen records have been verified, and 41% of the verified records are only identified to morphospecies. This limits our understanding of regional diversity and distribution patterns but provides ample opportunity for further taxonomic study. Expanding monitoring programs to include Exmouth Gulf and the Muiron Islands, along with unique habitats such as the King Reef artificial reef, and conducting additional biodiversity, demographic, and ecosystem health research is essential to assess the cumulative impacts of climate change and other environmental stressors on the unique and culturally significant marine ecosystems of this region. Full article

Octocorals have proven to be a prolific source of bioactive natural products, exhibiting a wide spectrum of pharmacological activities. Among octocorals, Pennatulaceans, commonly known as sea pens, are among the most dominant soft coral species living in benthic communities. Nonetheless, reports on bioactivity and chemical investigations of this genus are scarce. This prompted us to shed light on the pharmacological potential of the extracts of the sea pen Pennatula phosphorea, Linneus 1758, and gain an overview of its metabolome. Crude octocoral extracts, obtained with a modified Kupchan extraction protocol, were assessed for their bioactivity potential, revealing the hexanic extract to exert anti-inflammatory effects and interesting protective properties in an in vitro model of sarcopenia and in auditory HEI-OC1 cisplatin-treated cells, while the chloroformic extract was active in reducing A375 melanoma cell viability in a concentration-dependent manner. An untargeted metabolomic analysis unveiled that P. phosphorea collects a wide array of glycerophospholipids and phosphosphingolipids belonging to the ceramide phosphoinositol class, which were exclusive or more abundant in the hexanic extract. Their proven anti-inflammatory and cytoprotective effects could demonstrate the activity shown by the P. phosphorea hexanic extract. In addition, a group of prostaglandins, eluted mainly in the chloroformic extract, were putatively annotated. Since prostanoids from marine origin have been demonstrated to exert cytotoxic and anti-proliferative properties against various cancer cell lines, the presence of PGs in the P. phosphorea chloroform extract could justify its anti-melanoma activity. This is the first report on the presence of glycerophospholipids, phosphosphingolipids, and prostaglandins, along with the identification of novel congeners, in sea pens. Full article

The evolutionary history of the Caribbean candelabrum octocorals from the genus Eunicea (Plexauridae: Octocorallia) remains unknown despite their high diversity and abundance in reef environments. Understanding the evolutionary relationships between and within the Eunicea species is critical to accurately measuring the group diversity. Furthermore, this group has a high potential for cryptic diversity and new species, particularly given the rich morphological variability. Conventional molecular markers, however, have not provided a precise positioning for the species inside the genus. Here, we provide the first phylogenomic reconstruction of these candelabrum octocorals employing NextRAD, a reduced-representation sequencing technique, to generate thousands of SNPs. We include 15 morphospecies sampled between valid and new species throughout the Caribbean. At large, the phylogeny is well supported and resolved. In total, 13 species-level clades are discernible, including two lineages with demonstrated genetic and morphological variation that are considered and described as two new species, Eunicea criptica sp. nov. and E. colombiensis sp. nov., both previously assigned as E. clavigera and the second as the “thick morphotype”, thereby increasing the diversity of the group. Understanding the magnitude of species diversity within Eunicea is essential for directing conservation initiatives and clarifying the biological processes in reef ecosystems. Full article

Various photographs of the West Atlantic hoary rubble crab, Banareia palmeri (Rathbun, 1894), published on the internet show individuals being perched on branching octocorals. This habitat relationship has not been given attention in the scientific literature. The crab belongs to the brachyuran decapod family Xanthidae, which includes other species that associate with corals and zoantharians. Other aspects of the biology of B. palmeri, such as its diet, are unknown. During a night dive in Bonaire, an individual of B. palmeri was observed cutting off the tip of a sea rod, Pseudoplexaura sp., and pulling the loose fragment to its hiding place. The crab has also been observed in association with other octocoral species, such as Gorgonia ventalina Linnaeus, 1758. Close examination of the crab’s claws revealed that the inner edges resemble saws by bearing tooth-like structures with sharp edges, which explains how this animal is able to cut through the coral’s soft tissue and horny axis. These findings suggest that the crab is an expert in clipping octocoral branches, which may explain why some sea rod branches can be observed missing their original rounded tips and have regenerated pointy ends instead. Considering the octocoral’s regeneration capacity, it would be relevant to study how fast these branch tips are able to heal and whether fragments escaping from the crab’s claws are able to survive. Future examination of the crab’s gut contents and aquarium experiments may be able to provide more information about its dietary preferences. Full article

The Mediterranean Sea, a global biodiversity hotspot, faces significant threats that compromise its ecological health. While Marine Protected Areas (MPAs) play a crucial role in biodiversity conservation, their effectiveness is debated, and empirical data on their impact remain limited. This study evaluates the utility of Local Ecological Knowledge (LEK) from divers along the Spanish Mediterranean coast to assess perceived abundance of sentinel species in both MPAs and non-protected areas, in relation to empirical data, alongside divers’ attitudes toward ocean threats and conservation strategies. Divers perceived higher abundance and subjective health indicators of key species, such as Posidonia oceanica, octocorals, and top predators within MPAs, which aligns with empirical evidence supporting MPA effectiveness in conserving biodiversity and mitigating human disturbances. Notably, divers showed knowledge gaps, particularly underestimating climate change impacts while overemphasizing pollution threats. Diver education emerged as a critical factor in shaping conservation attitudes, with higher education levels correlating with increased environmental awareness and stronger support for conservation measures. This study underscores the potential of leveraging LEK in marine conservation strategies while acknowledging limitations related to self-reported data and regional specificity, advocating for expanded geographic scope and integration with empirical data in future research. Full article

We sequenced and analyzed the complete mitogenome of a Norwegian isolate of the octocoral Alcyonium digitatum using the Ion Torrent sequencing technology. The 18,790 bp circular mitochondrial genome was found to harbor the same set of 17 genes, which encode 14 protein subunits, two structural ribosomal RNAs and one tRNA, as reported in other octocorals. In addition, we detected a new tRNA^Pro-like gene sequence nested within the MutS protein coding region. This putative tRNA gene feature appears to be conserved among the octocorals but has not been reported previously. The A. digitatum mitogenome was also shown to harbor an optional gene (ORFA) that encodes a putative protein of 191 amino acids with unknown function. A mitogenome-based phylogenetic analysis, presented as a maximum likelihood tree, showed that A. digitatum clustered with high statistical confidence with two other Alcyonium species endemic to the Mediterranean Sea and the Southeast Pacific Ocean. Full article

The high diversity and biomass of organisms associated with coral communities depend directly on the maintenance or changes in the benthic composition. Over a decade, we evaluated the spatiotemporal variation in the benthic structure and composition of an insular coral community in the Northeastern Tropical Pacific. Our results show that local conditions drive spatiotemporal differences, and benthic organisms such as sponges, crustose coralline algae, octocorals, and hydrocorals all increased in abundance (cover) in response to negative thermal anomalies caused by the 2010–2011 La Niña event. In contrast, abnormally high temperatures, such as those recorded during the 2015–2016 El Niño Southern Oscillation (ENSO) event, explain the loss of scleractinian corals and crustose coralline algae coverage, which reduced the benthic groups’ richness (BGR), diversity (H’_BG), and evenness (J’_BG), with evidence of a consequent decrease in ecosystem function recorded the following year. Our analysis also showed that sites with high habitat heterogeneity harbored higher average BRG and H’_BG values and were less affected by environmental fluctuations than sites with high live scleractinian coral cover and lower BRG and H’_BG values. Therefore, the benthic structure was impacted differently by the same perturbation, and changes in the benthic community composition affected the groups associated with the community and ecological functions. More importantly, regional stressors such as the ENSO event caused only temporary changes in the benthic community structure, demonstrating the high resilience of the community to annual and interannual stressors. Full article

Octocoral of the genus Clavularia is a kind of marine invertebrate possessing abundant cytotoxic secondary metabolites, such as prostanoids and dolabellanes. In our continuous natural product study of C. spp., two previously undescribed prostanoids [clavulone I-15-one (1) and 12-O-deacetylclavulone I (2)] and eleven known analogs (3–13) were identified. The structures of these new compounds were elucidated based on analysis of their 1D and 2D NMR, HRESIMS, and IR data. Additionally, all tested prostanoids (1 and 3–13) showed potent cytotoxic activities against the human oral cancer cell line (Ca9-22). The major compound 3 showed cytotoxic activity against the Ca9-22 cells with the IC₅₀ value of 2.11 ± 0.03 μg/mL, which echoes the cytotoxic effect of the coral extract. In addition, in silico tools were used to predict the possible effects of isolated compounds on human tumor cell lines and nitric oxide production, as well as the pharmacological potentials. Full article

The recent rise in ocean temperatures, accompanied by other environmental changes, has notably increased the occurrence and spread of diseases in Octocorallia, many species of which are integral to shallow tropical and subtropical coral reef ecosystems. This study focuses on the understanding of these diseases, which has been largely limited to symptomatic descriptions, with clear etiological factors identified in only a fraction of cases. A key example is the multifocal purple spots syndrome (MFPS) affecting the common Caribbean octocoral sea fan Gorgonia ventalina, linked to the gall-forming copepods of the genus Sphaerippe, a member of the widespread family, Lamippidae. The specialized nature of these copepods as endoparasites in octocorals suggests the potential for the discovery of similar diseases across this host spectrum. Our investigation employed four molecular markers to study disease hotspots in Saint Eustatius, Curaçao, northwest and southwest Cuba, and Bonaire. This led to the discovery of a group of copepod species in these varied Caribbean locations. Importantly, these species are morphologically indistinguishable through traditional methods, challenging established taxonomic approaches. The observed diversity of symbionts, despite the host species’ genetic uniformity, is likely due to variations in larval dispersal mechanisms. Our phylogenetic analyses confirmed that the Lamippidae copepods belong to the order, Poecilostomatoida (Copepoda), and revealed their sister group relationship with the Anchimolgidae, Rhynchomolgidae, and Xarifiidae clades, known for their symbiotic relationships with scleractinian corals. These results add to our understanding of the evolutionary and ecological interactions of copepods and their hosts, and the diseases that they cause, and are important data in a changing climate. Full article

This research provides an extensive analysis of the biodiversity and distribution patterns of copepod crustaceans associated with octocoral species. A comprehensive dataset comprising 966 records pertaining to 233 copepod species, encompassing 54 genera, 18 families, and 3 orders, was compiled from 92 scientific papers published between 1858 and 2023, and updated as open data to GBIF. These copepods were found to be closely associated with 183 octocoral species, representing 72 genera and 28 families. The analysis revealed a total of 393 distinct interspecific associations between copepods, classified under the orders Cyclopoida, Harpacticoida, and Siphonostomatoida, and diverse octocorals. Approximately 60% of these associations were reported only once in the literature, which poses challenges to assessing the level of host specificity among the majority of copepod species linked with octocorals. Notably, over 91% of the recorded copepod species were found at depths not exceeding 30 m, with only four copepod species reported at greater depths surpassing 500 m. The presence of these symbiotic copepods was documented across 215 sampling sites situated within 8 of the 12 defined marine ecoregions, with particular attention to the Western Indo-Pacific, Central Indo-Pacific, and Temperate Northern regions. Despite the comprehensive examination of available data, this study highlights substantial gaps in our comprehension of copepod crustacean diversity and distribution in association with octocorals. Moreover, crucial information concerning symbiotic copepods is conspicuously absent for approximately 94% of potential octocoral host species. These disparities emphasize the imperative need for further scientific inquiry to unveil the intricacies of symbiotic relationships and to contribute to a more holistic understanding of copepod–octocoral associations. Full article

A new shrimp species of the genus Periclimenes is described based on specimens collected in the Bissagos Islands, Guinea-Bissau. Specimens were collected from an unidentified octocoral. This is the ninth species in the genus known to be from the East Atlantic and Mediterranean. Full article

The rapid reduction in coral reefs worldwide has led to increasing attention toward protecting and restoring coral reef ecosystems. Coral reefs not only have a rich diversity of coral species, but they can also provide important products and services for human beings. One type of coral, Echinogorgia, has important scientific research value and application prospects. To understand the diversity of coral species, diving surveys were conducted in Xiamen Bay in 2017 and 2021, and a total of 928 samples were collected. Taxonomic research was conducted using methods such as morphological identification through electron microscopy. Specific phylogenetic trees of the COI gene, mtMuts gene, and ITS1 gene were analyzed. There were 47 specimens of Echinogorgia coral included among 928 samples. Fifteen species of Echinogorgia were identified, including Echinogorgia ramosa, Echinogorgia flexilis, Echinogorgia russelli, Echinogorgia ramulosa, and Echinogorgia gracilima (which represent the newly recorded species in the waters of China). This study increases the species diversity records in China and contributes to new geographical distribution information of Echinogorgia worldwide. The primary data also serve as the baseline data for long-term biomonitoring programs to estimate the status of octocorals in Xiamen Bay. Full article

We document the benthic ctenophores Coeloplana sp. and Vallicula multiformis from Oman, extending their geographic range. A new Coeloplana species was found forming aggregations on gorgonians of two octocoral host genera, Melithaea and Euplexaura, representing associations previously unknown to occur in the Indo-West Pacific region. Our findings also illustrate the concurrent presence of the ectocommensal ophiuroid Ophiothela mirabilis, which adversely affects other Coeloplana species in the tropical West Atlantic, where it is considered invasive. This exploration contributes to our understanding of the biogeography, species distribution, and ectosymbiotic associations of these genera, setting the stage for a comprehensive species description and in-depth analysis of host relationships in future studies. Full article

Inflammation is a critical defense mechanism that is utilized by the body to protect itself against pathogens and other noxious invaders. However, if the inflammatory response becomes exaggerated or uncontrollable, its original protective role is not only demolished but it also becomes detrimental to the affected tissues or even to the entire body. Thus, regulating the inflammatory process is crucial to ensure that it is resolved promptly to prevent any subsequent damage. The role of neutrophils in inflammation has been highlighted in recent decades by a plethora of studies focusing on neutrophilic inflammatory diseases as well as the mechanisms to regulate the activity of neutrophils during the overwhelmed inflammatory process. As natural products have demonstrated promising effects in a wide range of pharmacological activities, they have been investigated for the discovery of new anti-inflammatory therapeutics to overcome the drawbacks of current synthetic agents. Octocorals have attracted scientists as a plentiful source of novel and intriguing marine scaffolds that exhibit many pharmacological activities, including anti-inflammatory effects. In this review, we aim to provide a summary of the neutrophilic anti-inflammatory properties of these marine organisms that were demonstrated in 46 studies from 1995 to the present (April 2023). We hope the present work offers a comprehensive overview of the anti-inflammatory potential of octocorals and encourages researchers to identify promising leads among numerous compounds isolated from octocorals over the past few decades to be further developed into anti-inflammatory therapeutic agents. Full article

The Persian Gulf, a young and shallow epicontinental sea, is known for its unique geological and oceanographic characteristics that foster its diverse and productive marine ecosystems. A substantial portion of the Gulf’s seafloor consists of unconsolidated soft sediments, making it unsuitable for colonization by many sessile organisms. Consequently, relatively few hard grounds and submerged banks provide suitable habitats for benthic and substrate dwellers. This study documents a unique marine habitat on an offshore submerged bank, likely a raised salt dome, south of Qeshm Island, Iran. This area is home to a high concentration of ahermatypic coral species and remains relatively sheltered from human activities. The bank’s geographic location allows inflow currents from the Strait of Hormuz to transport larvae and nutrients, providing suitable substrates for various sessile invertebrates. Moreover, it causes the formation of Taylor columns, which affect fluid dynamics and circulation patterns, indirectly enhancing biodiversity. Despite facing risks from large-scale regional and localized threats, the bank’s remoteness from the main coast and its depth provide some protection. This study emphasizes the need for continued exploration and the implementation of effective conservation measures in the region, along with additional research to clarify the ecological and physical parameters supporting its diversity. It also presents the first in situ photographic evidence for the occurrence of some octocoral genera in the Gulf. Future research should investigate how the species compositions of hidden banks and shoals contribute to the overall biodiversity of the Persian Gulf. Full article