Marine Biodiversity Hotspot Research Articles

Characterizing Marine Heatwaves in the Kerguelen Plateau Region

Marine heatwaves (MHWs) are prolonged extreme oceanic warm water events. Globally, the frequency and intensity of MHWs have been increasing in recent years, and it is expected that this trend is reflected in the Kerguelen Plateau region. MHWs can negatively impact the structure of marine biodiversity, marine ecosystems, and commercial fisheries. Considering that the KP is a hot-spot for marine biodiversity, characterizing MHWs and their drivers for this region is important, but has not been performed. Here, we characterize MHWs in the KP region between January 1994 and December 2016 using a combination of remotely sensed observations and output from a publicly available model hindcast simulation. We describe a strong MHW event that starts during the 2011/2012 austral summer and persists through winter, dissipating in late 2012. During the winter months, the anomalous temperature signal deepens from the surface to a depth of at least 150 m. We show that downwelling-favorable winds occur in the region during these months. At the end of 2012, as the MHW dissipates, upwelling-favorable winds prevail. We also show that the ocean temperature on the KP is significantly correlated with key modes of climate variability. Over the KP, temperature at both the ocean surface and at a depth of 150 m correlates significantly with the Indian Ocean Dipole. To the south of the KP, temperature variations are significantly correlated with the El Niño Southern Oscillation, and to both the north and south of the KP, with the Southern Annular Mode. These results suggest there may be potential predictability in ocean temperatures, and their extremes, in the KP region. Strong MHWs, like the event in 2012, may be detrimental to the unique ecosystem of this region, including economically relevant species, such as the Patagonian Toothfish.

Underwater Visual Census of Deeper Vertical Rocky Reefs

Diver-based underwater visual census (UVC), particularly transect-based survey, is a widely used method for the study of tropical and temperate fish assemblages. However, due to logistical constraints associated with conventional SCUBA diving, deeper habitats, such as vertical rocky reefs, are rarely studied and poorly known. This paper describes the Deep Vertical Transect (DVT) method as a safe and effective method for assessing fish in waters up to 50 m of depth. It is based on sampling of vertical transects browsing within it (S-type transect) by divers using Full HD video cameras. The diving profile includes the use of deep decompression stops and Nitrox 50 as a decompression gas. Hence, the study yields information on fish assemblages associated with deeper vertical coralligenous reefs. The results of 51 recorded species, yielded 41 considered as reef-associated and 10 as occasional. This suggests that underwater steep coralligenous reefs are marine biodiversity hotspots. They may be considered to represent a distinctive marine subecosystem, possessing its own food chain, with the depth, in relation to temperature, as the most important factor responsible for the diversity of fish assemblages within this habitat.

Distinctive Community Patterns With Exceptional Diversity of Polychaetes Around a Tectonically Active Archipelago in the Tropical Indian Ocean

Marine soft-sediments sustain functionally important benthic assemblages that are critical for remineralization of organic matter and supply of nutrients to the water column. While these assemblages are well studied along continental margins, investigations from insular margin that surround oceanic islands are very limited. This paper examines the distribution and standing stock of macrozoobenthos at 50, 100, and 200 m depth contours surrounding the Andaman and Nicobar archipelago in the tropical Indian Ocean. The standing stock of macrozoobenthos decreased from the mesophotic reef areas (50 m depth) to the deeper strata (200 m), particularly in the case of the dominant groups, the polychaetes and crustaceans. Smaller-sized, interstitial polychaetes and crustaceans were abundant in the coarser sandy sediments at the shallower sites. The polychaetes were represented by 606 species (279 genera) in the study, of which >50% were rare species. Based on polychaete species composition, three regions were delineated in the study area - the Nicobar margin, the western margin of the Andaman (Bay of Bengal sector), and the eastern margin of the Andaman (Andaman Sea sector). The long, uninterrupted Andaman Island chain formed a geographic barrier separating the eastern and western margins, resulting in the regional distinctions in sediment nature and hydrographic characteristics, which in turn influenced species distribution. Corresponding differences were absent in the case of the Nicobar Islands, which are widely separated by transecting channels, permitting exchange of water between the Bay of Bengal and the Andaman Sea. Within the three regions, polychaete communities changed significantly in taxonomic and functional composition with increasing depth. The well oxygenated, coarse sandy sediments around mesophotic reefs (50 m) harboured predator-dominated assemblages. The 200 m sites, which were characterised by oxygen minimum conditions (<0.5 ml.l-1), particularly around the Andaman Island mass, were dominated by deposit feeders. This study provides the first comprehensive dataset on distribution and standing stock of macrozoobenthos, and community structure of polychaetes along the Andaman and Nicobar insular margin. It also revealed the highest number of polychaete species ever recorded in the northern Indian Ocean, indicating that the Andaman and Nicobar margin is a significant marine biodiversity hotspot.

Artisanal fisher perceptions on ghost nets in a tropical South Atlantic marine biodiversity hotspot: Challenges to traditional fishing culture and implications for conservation strategies

Ghost fishing, the ability of fishing equipment to continue to capture organisms even after it is no longer controlled, leads to serious marine impacts, including bycatch, which contributes to biodiversity loss. Insistent complaints from artisanal fisher in the state of Bahia, Brazil, concerning the impacts of nets lost or abandoned by fisher from other regions that operate in their traditional fishing territory were brought to the attention of our research group. Therefore, this study aims to describe the knowledge and classify fisher perceptions in south Bahia regarding ghost fisheries in the region, as well as the resulting impacts and fisher ideas for solving this problem in a coastal coral reef region. Semi-structured interviews were conducted between August 2015 and September 2017 with 60 fishers, 59 men and one woman, that fish with hand lines and hooks in the studied area. A total of 90% of respondents (n = 54) reported having found ghost nets in their ancestral fishing territories, while 93% (n = 56) associated ghost nets with financial losses and marine environment impacts. Most respondents (n = 56; 93%) also indicated lower fishery yields due to ghost nets and indicated (n = 55; 91.9%) that most ghost nets found in the area are used for lobster fishing, which is banned in Brazil. Fishers revealed an active interest in solving this socio-environmental problem, demonstrating detailed knowledge related to the loss of fishing nets in the local marine environment, as they have been finding and removing ghost nets from the local sea. Fisher's ideas to solve this problem included the implementation of fines for fishers caught in breach of regional and national fisheries regulations, and management actions, such as ghost net removal from the sea. Establishing partnerships between fisher and the federal government in curbing ghost fisheries is crucial.

The Giant Marine Gastropod Campanile Giganteum (Lamarck, 1804) as a High‐Resolution Archive of Seasonality in the Eocene Greenhouse World

AbstractGiant gastropods are among the largest mollusks in the fossil record, but their potential as paleoseasonality archives has received little attention. Here, we combine stable isotope and trace element analyses with microscopic observations and growth modeling on shells of two species of the gastropod genus Campanile: the extinct Campanile giganteum from Lutetian (~45 Ma) deposits in the Paris Basin (France), the longest gastropod known from the fossil record, and its modern relative Campanile symbolicum from southwestern Australia. The C. giganteum shells contain original aragonite and have pristine nacre in their apertures. We show that these gastropods attained growth rates exceeding 600 mm/year along their helix, depositing over 300 cm3 aragonite per year. High growth rates and excellent preservation make C. giganteum excellent archives for reconstructing environmental change at high (potentially daily) temporal resolution, while providing enough material for methods such as clumped isotope analysis. Growth models show that Campanile gastropods grew nearly year‐round, albeit slower in winter. Stable oxygen isotope ratios in modern C. symbolicum faithfully record a seasonal variability of 18–25°C in sea surface temperature, only failing to record the coolest winter temperatures (down to ~16°C). Similarly, C. giganteum specimens likely record a nearly complete seasonal temperature range. Assuming constant sea water isotope composition, their oxygen isotope seasonality of up to 2.5‰ would translate to a Lutetian temperature range of 21–32°C in the Paris Basin. We hypothesize that these high and seasonally variable temperatures formed the breeding ground for the Lutetian shallow marine biodiversity hotspot in the Paris Basin.

Global distribution of coral diversity: Biodiversity knowledge gradients related to spatial resolution

AbstractBiodiversity knowledge shortfalls, especially incomplete information on species distributions, can lead to false conclusions about global biodiversity patterns. Diversity estimation theory statistically uses species occurrence records and sampling completeness (coverage) to predict diversity in terms of species richness, dominance and evenness. We estimated Scleractinia coral species diversity at different spatial resolutions, based on 109,296 occurrences and range data for 697 species, using an incidence‐based Hill's numbers approach through a rarefaction and extrapolation technique. We found that spatial patterns of diversity estimates were dependent on a geographic scale. The latitudinal and longitudinal diversity gradients, particularly at finer spatial scales, differed from species range‐based coral biodiversity hotspots of previous studies. The western Indian Ocean was predicted to have the most coral species, with greater diversities than in the Indo‐Pacific Coral Triangle. We concluded that the identification of marine biodiversity hotspots is sensitive to species commission errors (from range maps) and biased sampling coverage. Moreover, estimates of the geographic distribution of species richness informed us of a set of priority areas (the northeastern coast of Australia, central Coral Triangle and coast of Madagascar) for future sampling of unknown coral species occurrence. Our findings of biogeographical survey priorities contribute to filling biodiversity shortfalls for tropical coral reefs through sampling completeness, and consequently for development of conservation planning.

Biodiversity and structure of marine sponge assemblages around a subtropical island

We evaluated the structural responses of marine sponge assemblages to different substrates as well as their positioning around Ilha Grande, a local hotspot of marine biodiversity sheltered in a bay area off Southeast Brazil. Sampling sites were distributed between sides of the island facing the continent (North) and ocean (South) across two depth-dependent substrates. As proved by ordination and permutation analyses, these two factors accounted for nearly half the variation observed among assemblages, either with species abundance or coverage area data. Out of 46 OTUs surveyed (~ 3000 individuals), Tedania (Tedania) ignis, Scopalina ruetzleri, and Iotrochota arenosa dominated the community, even though most of the dissimilarity detected among assemblages relied on 20% of the OTUs. The northern side was proved as more diverse, and the south-facing side held more unspecific, putatively new OTUs. Assemblages dwelling on rocky-to-sandy interface bottoms were meager in species number, although they mainly included Dragmacidon reticulatum and the endemic Brazilian sponge Polymastia janeirensis. By highlighting structuring factors operating on Ilha Grande’s sponge assemblage, we hope to support future monitoring surveys on an environment increasingly impacted by human activities over the years.

A Preliminary inventory of alien and cryptogenic species in Monastir Bay, Tunisia: spatial distribution, introduction trends and pathways

The Mediterranean Sea is a marine biodiversity hotspot under threat. One of the major impacts on its biological resources and services comes from the invasiveness of non-indigenous species (NIS). Nevertheless, NIS monitoring programs in the south basin of the Mediterranean Sea are in an early implementation stage. This study aims to describe NIS and cryptogenic species distribution in Monastir Bay (Tunisia) and to identify risk areas for the introduction and spread of invasive species, providing a baseline for future monitoring programs. To this end, a series of Rapid Assessment Surveys were carried out to identify NIS and cryptogenic species in one marina, five fishing ports, two aquaculture farms and the Special Conservation Area of the Kuriat islands. 24 species were found, of which 11 constitute new records for Monastir Bay, which represent a 33.3% of the total NIS reported in this Bay. Assemblages differed between substrata types, being NIS more abundant in artificial than in natural substrata. Regarding locations, Cap Monastir Marina was the most invaded site, the most transited by vessels and the only one visited by international sailing. Hence, this marina constitutes the main risk area to be monitored, although the fishing ports and fishing farms in the semi-enclosed coastal lagoon of Monastir Bay can also be considered as risk areas. Nevertheless, more research effort is needed in Monastir Bay in order to update the records of NIS and cryptogenic species and increase insight on the ecological evolution of these species and their related impacts on natural communities and marine resources.

Microplastics on the Menu: Plastics Pollute Indonesian Manta Ray and Whale Shark Feeding Grounds

The implications of plastic pollution, including microplastics, on marine ecosystems and species are increasingly seen as an environmental disaster. Yet few reports focus on filter-feeding megafauna in regions heavily impacted by plastic pollution, such as Indonesia in the Coral Triangle, a global marine biodiversity hotspot. Here, we evaluate plastic abundance and characterize debris from feeding grounds for manta rays (Mobula alfredi) and whale sharks (Rhincodon typus) in three coastal locations in Indonesia: Nusa Penida Marine Protected Area, Komodo National Park, and Pantai Bentar, East Java. A 200 µm plankton net was used to sample the top 0.5 m of the water column (‘trawl survey’) and floating plastics were assessed along ~ 440 m long transects (‘visual survey’) during the Indonesian north-west (‘wet’) and south-east (‘dry’) monsoon seasons during 2016 – 2018. Microplastics were identified visually, measured and categorized from trawl samples, and larger floating plastics were counted from vessels in visual transects. Plastic abundance ranged widely from 0.04 to 0.90 pieces m-3 (trawl survey) and 210 to 40,844 pieces km-2 (visual survey). Results from linear models showed significant seasonal and location differences in estimated plastic abundance for trawl and visual surveys in Nusa Penida and Komodo. Plastic abundance was up to ~ 44 times higher in the wet than the dry season, with the largest seasonal effect observed in Nusa Penida. Overall, small pieces 50% combined) were the most prevalent plastics. Theoretical plastic ingestion rates were calculated using estimated filtration volumes of manta rays and whale sharks and the mean plastic abundance in their feeding grounds. Upper plastic ingestion estimates for manta rays were ~ 63 and 25 pieces h-1 for Nusa Penida and Komodo locations, respectively, and ~137 pieces h-1 for whale sharks in Java. Analysis of manta ray egested material confirmed plastic ingestion, the consequences of which might include exposure to toxic plastic additives and adhered persistent organic pollutants. Communicating this information to communities who stand to benefit from healthy megafauna populations might help local governments as they work towards reducing plastics in the marine environment.

Capturing the big picture of Mediterranean marine biodiversity with an end-to-end model of climate and fishing impacts

The Mediterranean Sea is one of the main hotspots of marine biodiversity in the world. The combined pressures of fishing activity and climate change have also made it a hotspot of global change amidst increasing concern about the worsening status of exploited marine species. To anticipate the impacts of global changes in the Mediterranean Sea, more integrated modelling approaches are needed, which can then help policymakers prioritize management actions and formulate strategies to mitigate impacts and adapt to changes. The aim of this study was to develop a holistic model of marine biodiversity in the Mediterranean Sea with an explicit representation of the spatial, multispecies dynamics of exploited resources subject to the combined influence of climate variability and fishing pressure. To this end, we used the individual-based OSMOSE model (Object-oriented Simulator of Marine ecOSystEms), including 100 marine species (fish, cephalopods and crustaceans) representing about 95% of the total declared catch, at a high spatial resolution (400 km2) and a large spatial scale (the entire Mediterranean basin) – the first time such a resolution and scale have been modelled. We then combined OSMOSE with the NEMOMED 12 physical model and the Eco3M-S biogeochemical low trophic level model to build the end-to-end model, OSMOSE-MED. We fitted OSMOSE-MED model with observed or estimated biomass and commercial catch data using a likelihood approach and an evolutionary optimization algorithm. The outputs of OSMOSE-MED were then verified against observed biomass and catch data, and compared with independent datasets (MEDITS data, diet composition and trophic levels). The model results – at different hierarchical levels, from individuals to the scale of the ecosystem – were consistent with current knowledge of the structure, functioning and dynamics of the ecosystems in the Mediterranean Sea. While the model could be further improved in future iterations, all the modelling steps – the comprehensive representation of key ecological processes and feedback, the selective parameterization of the model, and the comparison with observed data in the validation process – strengthened the predictive performance of OSMOSE-MED and thus its relevance as an impact model to explore the future of marine biodiversity under scenarios of global change. It is a promising tool to support ecosystem-based fishery management in the Mediterranean Sea.

Non-indigenous macrophytes in Adriatic ports and transitional waters: Trends, taxonomy, introduction vectors, pathways and management

The Adriatic Sea is considered as a hotspot of marine biodiversity but, due to intense human activities (e.g. maritime transport, mariculture), it is also a recipient area of non-indigenous species (NIS). This study analyzed the scientific literature on non-indigenous macrophytes (NIM) recorded in ports, marinas and transitional waters (TWs) of the Adriatic Sea, in the period 1987–2018. The results show that 51 out of 118 Mediterranean NIM are found in Adriatic ports and TWs. The Venice Lagoon is the main Adriatic recipient area of NIM. Mariculture is the main vector of introduction, whereas the principal pathways of NIM dispersal are shipping and shellfish transfer. The largest group of NIM is of temperate northern Pacific origin. This study corroborated the fact that ports and TWs act as dispersal hubs and invasion hotspots. The importance of early detection of NIM at such sites should be considered in any environmental management strategy.

Larger Benthic Foraminifera from the Panna and Mukta Fields Offshore India: Paleobiogeographical Implications

AbstractA previously undocumented, diverse assemblage of very shallow-water larger benthic foraminifera (LBF) is described from the Panna-Mukta fields, offshore India. This location lies at the margin of the late Eocene to early Miocene Arabian Peninsula marine biodiversity hotspot. The assemblage has similar characteristics to those from the Middle East, Oman and Turkey, but shares little in common with onshore western Indian assemblages. In addition, the material contains several unusual and possibly new taxa, and extends the geographic ranges of several existing LBF. The succession spans the Eocene and Oligocene, with an unconformity between the middle and upper Eocene. As such it offers insight into the response of shallow-water taxa to the Eocene–Oligocene Transition extinction event from an unusual setting in a little studied region. Our data show that LBF taxonomic richness in the Panna Mukta fields is comparable with highly diverse assemblages found in Oman, indicating it may be an eastward extension of this high diversity region. Moreover, significant decreases in diversity are seen between the middle and upper Eocene and the upper Eocene and Oligocene. Major extinctions are known to occur in global LBF records at both of these levels, and the Panna Mukta succession therefore further confirms these are global events, extending across the platform and having a dramatic (at least short-term) effect on high biodiversity regions.

High coral reef connectivity across the Indian Ocean is revealed 6\u20137\xa0Ma ago by a turbid-water scleractinian assemblage from Tanzania (Eastern Africa)

The present centre of coral diversity in the Western Indian Ocean is defined by the northern Mozambique Channel with an extension northward to Mafia Island in Tanzania (Eastern Africa). The geological and evolutionary history of this hotspot of marine biodiversity remains so far completely obscure, because Cenozoic fossil reef communities of this area are not well known. This study presents a new fossil scleractinian fauna from the Mikindani Formation in southern Tanzania. It comprises 16 symbiotic coral taxa of which nine could be identified to the species and five to the genus level. Coral habitat consisted of low-relief biostromes that developed in shallow water at the front of the Rovuma Delta under conditions of variable sediment input. The biostromes are dated to be Messinian based on associated calcareous nannoplankton and planktic foraminifers. The studied coral assemblage shows close affinities with the Recent Western Indian Ocean biogeographic province and Central Indo-West Pacific biogeographic region as well as with the Miocene of Indonesia. Faunistic relations with the Oligocene-early Miocene of Somalia and Iran do not exist. The patterns of species distribution document a major palaeobiogeographic change in the Indian Ocean that correlates with the onset of the Miocene Indian Ocean Equatorial Jet during the middle Miocene. The clear Indonesian affinity of the Messinian coral fauna from southern Tanzania implies that this westerly oceanic surface current provided high biogeographic connectivity across the Indian Ocean during the late Miocene. Today, the coastal waters of Indonesia are located in the Coral Triangle. Diversification of this global epicentre of marine biodiversity started in the early Miocene and it was established already during the middle Miocene. Our results indicate that the East African hotspot of coral biodiversity originated as an offshoot of the Coral Triangle in the middle to late Miocene.

Historical biogeography of herbivorous coral reef fishes: The formation of an Atlantic fauna

AbstractAimTo describe the global biogeography of key herbivorous coral reef fish groups since their presumed origins, using data from both fossil and extant species.LocationGlobal Cenozoic reefs.TaxonAcanthuridae (surgeonfishes), Siganidae (rabbitfishes) and Scarini (parrotfishes).MethodsWe applied the fossilized birth–death model to build chronograms including a comprehensive sampling of extant species and all the fossil occurrences described for each group. With the resulting chronograms, we built biogeographical models considering the geological changes in reef habitat availability since the ancient Tethys Sea. Finally, we used biogeographical stochastic mappings to trace the routes of colonization of the Atlantic Ocean by lineages in our focal taxa.ResultsWe found that the Palaeocene–Eocene was a period of significant lineage origination for surgeonfishes and rabbitfishes in the central Tethys Sea with the appearance of ancient genera. Most of these genera were probably extinct by the Eocene–Oligocene boundary as they do not correspond with modern taxa. Parrotfishes, however, originated in the early Oligocene, an epoch that corresponds with the geographical transition of the marine biodiversity hotspot. In all groups, extant genera had similar origin times and all expanded in the Miocene, mainly in the Indo‐Pacific. In the Atlantic, only one parrotfish lineage with Tethyan ancestry appears to have survived. It subsequently gave rise to extant endemic genera (Sparisoma and Cryptotomus). The other extant lineages in the Atlantic all have Indo‐Pacific origins and colonized more recently using different dispersal pathways.Main conclusionsThe Indo‐Pacific herbivorous fish fauna is the result of ongoing lineage expansion that started in the central Tethys. The Atlantic is a composite fauna with just one endemic lineage and at least four colonization events from the Indo‐Pacific.

Disasters and biodiversity: case study on the endangered endemic marine ornamental Banggai cardinalfish

Disasters are notoriously unpredictable; they can strike anytime, anywhere. However, in this Anthropocene Epoch, humanity has increased the likelihood of many disasters, as well as their likely severity and socio-ecological impacts, with implications for the future of natural resources; in particular, marine ecosystems and biodiversity, and the human communities who rely on them. This case study focussed on the Banggai cardinalfish (Pterapogon kauderni), a unique species of global conservation concern, and its native habitat in the Banggai Archipelago, at the centre of the Coral Triangle (CT) global marine biodiversity hotspot. To evaluate future risks and implications, we looked back to the past, including an overview of what is known regarding the origins and evolution of this species and its habitat, as well as past natural disasters in the Banggai Archipelago, Central Sulawesi, Indonesia. We then reviewed current status and trends affecting the likelihood of exposure and the vulnerability of endemic P. kauderni populations and habitat, overall and at the evolutionary significant unit (ESU) scale, to disasters caused by tectonic phenomena, disasters related to weather and anthropogenic climate change (e.g. mass coral bleaching, sea level rise), and the synergies between disaster impacts and localised human activities. Finally, we considered management options with potential for mitigating disaster risk and increasing resilience, with benefits for both biodiversity and human welfare, as well as avenues for future research. We conclude that local action can buy time, but it is likely that the eventual fate of this “flagship” species, as well as the human communities of this equatorial archipelago, depend on effective global action to curb the drivers of anthropogenic climate change.

The Critical Importance of Rhodoliths in the Life Cycle Completion of Both Macro- and Microalgae, and as Holobionts for the Establishment and Maintenance of Marine Biodiversity

Rhodoliths are the main hard substrata for the attachment of benthic macroalgae in the NW Gulf of Mexico rubble habitats that are associated with salt domes, unique deep bank habitats at ~50-90m depth on the continental shelf offshore Louisiana and Texas. With the advent of additional sequencing technologies, methodologies for biodiversity assessments are now rapidly shifting to DNA metabarcoding, i.e. High Throughput Sequencing (HTS) of environmental DNA mixtures with standardized molecular markers, such as 16S V4, for rapid, cost-effective biodiversity measurement. We newly tested 16S V4 metabarcoding on endolithic portions of mesophtic rhodoliths exhibiting low phototroph colonization that revealed a hidden, cryptic algal diversity targeting spores, propagules, and unsuspected life history stages. We explored cryo-SEM as a potentially more informative method than regular SEM to minimize artefacts of sample preparation in the study of endolithic cell inclusions which brought to light a suite of microalgal stages. We were able to differentiate floridean starch from cellular inclusions. We associated the effect of anatomical growth pattern on presence or absence of cellular inclusions in biogenic rhodoliths. Analyses of combined 16S V4 metabarcodes and 16S Sanger sequences of two red algal orders, the Halymeniales and Bonnemaisoniales, increased the established record of diversity in the region. We view rhodoliths as marine biodiversity hotspots that may function as seedbanks, temporary reservoirs for life history stages of ecologically important eukaryotic microalgae, or as refugia for ecosystem resilience following environmental stress.

Nature-based and technology-based solutions for sustainable blue growth and climate change mitigation in marine biodiversity hotspots

This paper discusses the urgent need for human interventions in maximizing the promise of blue growth while ensuring sustainability in all its dimensions. It spares no efforts in highlighting the critical nexus between ocean conservation, climate change mitigation and the ecosystem services. The interpretation underscores the threat that unchecked deterioration of marine environment would present for health of the planet and its people. It is evident that the nature-based solutions provide the best options, but the significance of disruptive technologies and innovations cannot be underestimated. However, the decisions pertaining to devising and applying solutions should be informed by scientific reasoning and available evidence. Increasing attention given to blue economy shows the importance of exploring the sustainable solutions by shaping research that helps in identifying the tangible and integrated actions to fast track our progress towards implementing the Sustainable Development Goals.

Functional reef fish groups of the Mexican Caribbean: implications of habitat complexity

The Caribbean Sea is considered a unique biogeographic region and is among the top 5 world hotspots of marine biodiversity. Yet, over the last years it is among the regions where the most serious declines in terms of reef area, health, and productivity is occurring. In this study, the coral reef fish community of the Mexican Caribbean was analyzed and classified into functional groups. The aims of this study were: 1) determine the functional relationships of the fish community based on diet and morphology, and 2) determine the extent of the influence of habitat complexity and the protection of the Sian-Ka'an reserve on the fish richness and functional diversity of the ecosystem. Eleven reef localities of the Yucatan Peninsula and 160 species were analyzed. Twenty-eight functional groups were described for both ecological and morphological variables. Our results indicate that variation in habitat complexity was a significant factor related to fish richness and functional diversity; however, the protection of the reserve does not show a relationship with any of the response variables. On the other hand, the slope is the reef zone with the highest fish richness in all localities, creating a belt of richness and connectivity in the whole area.

Microbial and Small Eukaryotes Associated With Reefs in the Upper Gulf of Thailand

Reef sites of Ko Samae San (S), Khao Ma Cho (K) and Ko Tao Mo (T) in the upper Gulf of Thailand have abundant corals and represent a hotspot of marine biodiversity. Coral reefs serve as major networks of food and energy, where bacteria, microbial eukaryotes (fungi) and small eukaryotes play significant roles as primary producers that convert inorganic compounds to organic compounds, degraders of toxic substances, and recyclers. These functions sustain food and energy supplies. Advances in metagenomics and next-generation sequencing can provide knowledge of diversity without cultivation limitations (e.g. culture media and culture condition). Scientists have researched bacterial diversity of coral sites; however, a database for fungi and small eukaryotes from Thailand’s sites with abundant corals is lacking. The present study utilized metagenomics combined F-RISA and 18S rRNA gene sequencing to unveil the first culture-independent microbial and small eukaryotes from these sites at two times in year and across four species of corals (Porites lutea, Platygyra sinensis, Acropora humilis and Acropora millepora), seawater and sediment. Results showed that the small eukaryotic communities on corals were distinct from communities in the surrounding seawater and sediment. The communities were relatively similar at the three sites and during the two periods of time. Pearson’s correlations indicated the community diversity were associated with water quality (e.g. dissolved oxygen concentrations and density of water).

Pliocene corals from the Togopi Formation of the Dent Peninsula, Sabah, northeastern Borneo, Malaysia

Saw, J.V.M., Hunter, A.W., Johnson, K.G. & Abdul Rahman, A.H.B., November 2018. Pliocene corals from the Togopi Formation of the Dent Peninsula, Sabah, northeastern Borneo, Malaysia. Alcheringa 43, 291–319. ISSN 0311-5518The palaeobiology of the Malay Archipelago region remains poorly documented, despite its present-day significance as a modern global marine biodiversity hotspot. The Togopi Formation of the Dent Peninsula, situated in Borneo on the western Sulu Sea and eastern coast of Sabah, Malaysia, preserves Plio-Pleistocene sedimentary sequences interpreted to represent localized transgressive episodes, and which have a relatively high coral diversity. Fossil corals were sampled from three available quarries on the Dent Peninsula, the sediments of which have been previously dated as 4.5–3.4 Ma in age based on foraminiferal data and radiometric analyses. These Pliocene corals are identified here based on their macromorphology, micromorphology and microstructural characteristics. In total, this study describes 28 fossil coral taxa, with 16 genera recognized and 22 taxa identified to species level, 21 of which can be confidently assigned to extant species. These new data have resulted in revised stratigraphic ranges for eight of these species. As the most comprehensive systematic survey of corals from the Pliocene of the Indo-Pacific to date, this study indicates a high diversity of corals on the margin of the Sabah Sea, Borneo, at this time, including taxa found today, thus casting doubt on the local impact of the Plio-Pleistocene extinction previously reported from faunal analyses of the central Indo-Pacific.Jasmin V.M. Saw [varnmay@yahoo.com] Department of Petroleum Geosciences, Universiti Teknologi PETRONAS, 32610 Seri Iskandar, Perak, Malaysia; Aaron W. Hunter* [awh31@cam.ac.uk] Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK; Kenneth G. Johnson [k.johnson@nhm.ac.uk] Department of Earth Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD, UK; Abdul Hadi B Abdul Rahman [hadi_rahman@utp.edu.my] Department of Petroleum Geosciences, Universiti Teknologi PETRONAS, 32610 Seri Iskandar, Perak, Malaysia. *Also affiliated with: School of Earth Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.