Francesca Benzoni

King Abdullah University of Science and Technology | KAUST · Division of Biological and Environmental Sciences and Engineering (BESE)

Deep-sea coral frameworks are understudied in the Red Sea, where conditions in the deep are conspicuously warm and saline compared to other basins. Habitat suitability models can be used to predict the distribution pattern of species or assemblages where direct observation is difficult. Here we show how coral frameworks, built by species within the...

Understanding how coral reefs respond to disturbances is fundamental to assessing their resistance and resilience, particularly in the context of climate change. Due to the escalating frequency and intensity of coral bleaching events, it is essential to evaluate spatio-temporal responses of coral reef communities to disentangle the mechanisms under...

Reef-building corals live in close mutualism with dinoflagellate algae (family Symbiodiniaceae), which play key roles in coral physiological performance and survival. Association patterns between host species and endosymbiont algae and their significance are still not fully understood, but they seem to affect the ability of hosts to inhabit differe...

Crustaceans are one of the most widespread and speciose groups of marine organisms, fulfilling multiple ecological roles in numerous ecosystems. On coral reefs, many crustacean species form associations with scleractinian corals. Although the Red Sea is considered a biodiversity hotspot, few studies examined the diversity of coral-associated crusta...

Globally, scleractinian coral diversity peaked in the Early Miocene (Burdigalian) and declined afterwards. In contrast to this global trend, scleractinian coral diversity in the Lower to Middle Miocene was low in the Red Sea, which had begun to open in the Oligocene and experienced its first marine incursion in the Burdigalian. Here, we report on c...

The ecological success of shallow water corals hinges on their association with photosynthetic Symbiodiniaceae algae. This is affected by environmental drivers among which sea temperature is pivotal. In 2016, a prolonged heat wave challenged New Caledonia reefs triggering a severe bleaching event. Here, we tracked 72 coral colonies comprising two s...

Black corals (Hexacorallia: Antipatharia) are a major component of mesophotic and deep marine ecosystems. Due to their preference for light deprived environments, black corals have historically been considered azooxanthellate, yet recent works have found them in association with dinoflagellates of the family Symbiodiniaceae down to 396 m depth. Whi...

Beneficial microorganisms for corals (BMCs), or probiotics, can enhance coral resilience against stressors in laboratory trials. However, the ability of probiotics to restructure the coral microbiome in situ is yet to be determined. As a first step to elucidate this, we inoculated putative probiotic bacteria (pBMCs) on healthy colonies of Pocillopo...

Black corals occur as part of benthic assemblages from shallow to deep waters in all oceans. Despite the importance in many benthic ecosystems, where these act as biodiversity aggregators, antipatharians remain poorly studied, with 75% of the known species occurring below recreational SCUBA diving depth limits. Currently, information regarding the...

Coral-dwelling gall crabs (Cryptochiridae) live in an obligate symbiosis with reef-building corals from shallow to deep waters. In particular, crabs of the genus Opecarcinus are known to occur across the tropical belt in association with the scleractinian family Agariciidae, down to a depth of 89 m. The Red Sea is a semi-enclosed basin that has lon...

Introduction The Red Sea is a narrow rift basin characterized by latitudinal environmental gradients which shape the diversity and distribution of reef-dwelling organisms. Studies on Symbiodiniaceae associated with select hard coral taxa present species- specific assemblages and concordant variation patterns from the North to southeast Red Sea coas...

Sexual reproduction is a crucial process for reef building coral populations to maximize genetic diversity and recover from large scale disturbances. Mass spawning events by Acropora species represent critical opportunities for populations to persist, and a process that is increasingly exploited to actively restore degraded reefs. However, the timi...

Octocorals (Cnidaria: Anthozoa) have a global distribution and form benthic assemblages along the depth gradient, from shallow to deep waters. They often occur below SCUBA diving limits, where they can become dominant habitat builders and aggregate different taxa. During a cruise in February 2023, one octocoral specimen was collected at 1453 m dept...

For decades, hydrothermal activity along the Red Sea Rift was only inferred from metalliferous sediments and hot brines. Active hydrothermal fluid discharge was never directly observed from this young ocean basin, but could be key to understanding the evolution of hydrothermal vent fields and associated life. Here we report the discovery of widespr...

The acrothoracican genus Berndtia Utinomi, 1950 includes small barnacles known to bore into the calcareous skeleton of living scleractinian corals of the genera Psammocora Dana, 1846 and Leptastrea Milne Edwards & Haime, 1849. The six known species of Berndtia are restricted to the tropical Western Pacific. We provide the first record of Berndtia f...

Beneficial Microorganisms for Corals (BMCs), or probiotics, enhance coral resilience against stressors in laboratory trials, being the only sustainable treatment currently explored to retain threatened native corals. However, the ability of probiotics to restructure the coral microbiome in situ is yet to be determined. To elucidate this, we inocula...

Despite covering a large amount of seafloor & representing a significant percentage of coral reef ecosystem biomass, Mesophotic Coral Ecosystems (MCEs) globally have been largely understudied in comparison to their shallow counterparts. The Red Sea is a unique and biodiverse tropical ecosystem, where few mesophotic coral reefs have been studied. To...

The diversity and evolution of the Red Sea invertebrates in mesophotic and deep-water benthic ecosystems remain largely unexplored. The Palaemonidae is a diversified family of caridean shrimps with numerous taxa in need of taxonomic revisions based on recent molecular analyses. The Red Sea mesophotic and bathyal palaemonid shrimps are largely unstu...

During two scientific expeditions between 2020 and 2022, direct surveys led to the discovery of free-living mesophotic foraminiferal-algal nodules along the coast of the NEOM region (northern Saudi Arabian Red Sea) where they form an unexpected benthic ecosystem in mesophotic water depths on the continental shelf. Being mostly spheroidal, the nodul...

A well-supported evolutionary tree representing most major lineages of scleractinian corals is in sight with the development and application of phylogenomic approaches. Specifically, hybrid-capture techniques are shedding light on the evolution and systematics of corals. Here, we reconstructed a broad phylogeny of Scleractinia to test previous phyl...

Coral-dwelling gall crabs (Cryptochiridae) are obligate symbionts of stony corals and occur on shallow and deep reefs across the tropical belt. The circumtropical genus Opecarcinus associates with Agariciidae corals, a dominant component of Mesophotic Coral Ecosystems (MCEs). Here, we report the first Red Sea mesophotic record, with 89 m as the dee...

Coral reefs accommodate a myriad of species, many of which live in association with a host organism. Decapod crustaceans make up a large part of this associated fauna on coral reefs. Among these, cryptochirid crabs are obligately associated with scleractinian corals, in which they create dwellings where they permanently reside. These gall crabs sho...

Two new symbiotic species of decapod crustaceans, a palaemonid shrimp and a porcellanid crab, are described from the same type locality situated on the campus of the King Abdullah University of Science and Technology (KAUST) in Thuwal, on the Red Sea coast of Saudi Arabia. The palaemonid shrimp Palaemonella jamila sp. nov. is described based on one...

A new snapping shrimp species of the Alpheus edwardsii (Audouin, 1826) group is described based on two specimens, one male and one female, collected on shallow-water reef flats of the Southern Ari Atoll in the Maldives, with a photographic record from Cebu in the Philippines. Alpheus octocellatus sp. nov. appears to be morphologically closest to A....

Introduction The northern Red Sea has been coined a refuge for reef corals due to the exceptional thermal tolerance of these organisms. With ocean warming threatening coral reefs worldwide, a panoptic characterization of corals living in extreme conditions may provide insights into future responses of corals to environmental change. Among other fac...

The family Euphylliidae consists of reef-building zooxanthellate scleractinian corals distributed across the Indo-Pacific. Seven extant genera comprising a total of 22 valid species are currently recognised. Recent studies have re-organised the taxonomy of the family at the genus level based on molecular and morphological data, including a comprehe...

The Red Sea is a suitable model for studying coral reefs under climate change due to its strong environmental gradient that provides a window into future global warming scenarios. For instance, corals in the southern Red Sea thrive at temperatures predicted to occur at the end of the century in other biogeographic regions. Corals in the Red Sea thr...

In November 2020, we observed several individuals and collected one juvenile of an unidentified anthiadine fish (Serranidae) between depths of 250 and 307 m near vertical walls of rocky reefs in the northern Red Sea. Further morphological and molecular analyses revealed that the collected specimen matches Sacura boulengeri, a species previously rep...

Very shallow coral reefs (<5 m deep) are naturally exposed to strong sea surface temperature variations, UV radiation and other stressors exacerbated by climate change, raising great concern over their future. As such, accurate and ecologically informative coral reef maps are fundamental for their management and conservation. Since traditional mapp...

Shallow coral reefs are biodiverse ecosystems currently severely at risk from anthropogenic disturbance and climate change. To ensure their survival through the Anthropocene, ecologically informative maps of these areas, that can guide ecosystem-based management, are necessary. In recent years, Unmanned Aerial Vehicles (UAVs) have emerged as a new...

A black coral, Bathypathes thermophila Chimienti, sp. nov. is described from the Saudi Arabian coasts of the Gulf of Aqaba and north Red Sea (Neom area) using an integrated taxonomic approach. The morphological distinctiveness of the new species is confirmed by molecular analyses. The species thrives in warm and high salinity waters typical of the...

Deep-sea brine pools represent hypersaline environments famed for their extremophile microbes. With anoxia entirely excluding bioturbating megafauna, brine pools are also conducive to the pristine preservation of sedimentary sequences. Here we use bathymetric and geophysical observations to locate a complex of brine pools in the Gulf of Aqaba consi...

The crucial role of crustose coralline algae (CCA) in inducing hard coral larval settlement and ensuring the replenishment of coral reefs is widely accepted, and so are the negative effects of anthropogenic CO2 emissions on both CCA abundance and coral development. However, diversified and well-developed coral reef communities have been recently di...

Scleractinian corals are a diverse group of ecologically important yet highly threatened marine invertebrates, which can be challenging to identify to the species level. An influx of molecular studies has transformed scleractinian systematics, highlighting that cryptic species may be more common than previously understood. In this study, we test th...

The scleractinian coral family Dendrophylliidae is a major component of shallow and deep-water coral ecosystems worldwide, but our knowledge on the evolutionary history of the family remains scarce. Here, we used ezRAD coupled with Illumina sequencing technology and reconstructed the complete mitochondrial genome of Dendrophyllia minuscula (GenBank...

The Stylasteridae, commonly known as lace corals, is a family of colonial calcifying hydrozoans mostly inhabiting deep waters. Stylasterids show a cosmopolitan distribution but, in some areas, they are characterized by low species diversity, such as in the Red Sea, where only a shallow-water species has been reported so far. With this work, we prov...

We present the NEOM Brine Pools, the first complex of brine pools discovered in the Gulf of Aqaba. The discovery was made at 1,770 m water depth and consists of one large pool (10,000 m ² ) flanked by three minor ones (<10 m ² ). Situated immediately at the toe-of-slope, the largest of the NEOM brine pools episodically receives terrestrial outwash...

The Red Sea is a maritime rift. Tsunamigenic submarine landslides are common in these deep, steep-sided, and seismically active basins. Because the rift is narrow, tsunami formed on one margin dissipate little before impacting the opposite side. Red Sea slope failures are therefore especially hazardous. We examine the tsunamigenic potential of an i...

The ability of corals to modulate their nutrition strategy in response to variable nutrient supply remains poorly understood, limiting our understanding of energy flow in coral reef ecosystems and thus our comprehension of their resilience to global changes. We used a naturally occurring nutrient gradient along the reef flat of two seabird-inhabite...

Sometimes called the “lab rat” of coral research, Stylophora pistillata (Esper, 1797) has been extensively used in coral biology in studies ranging from reef ecology to coral metabolic processes, and has been used as a model for investigations into molecular and cellular biology. Previously thought to be a common species spanning a wide distributio...

Climate change is causing the distribution and abundance of many organisms to change. In particular, organisms typical of the tropics are increasing in abundance in many subtropical regions, a process known as tropicalization. Here, we examine changes in coral abundance and assemblage structure in the Solitary Islands Marine Park (SIMP), over a 23-...

According to current experimental evidence, coral reefs could disappear within the century if CO2 emissions remain unabated. However, recent discoveries of diverse and high cover reefs that already live under extreme conditions suggest that some corals might thrive well under hot, high-pCO2, and deoxygenated seawater. Volcanic CO2 vents, semi-enclo...

Coral research is being ushered into the genomic era. To fully capitalize on the potential discoveries from this genomic revolution, the rapidly increasing number of high-quality genomes requires effective pairing with rigorous taxonomic characterizations of specimens and the contextualization of their ecological relevance. However, to date there i...

According to current experimental evidence, coral reefs could disappear within the century if CO2 emissions remain unabated. However, recent discoveries of diverse and high cover reefs that already thrive under extreme conditions seem to contradict these projections. Volcanic CO2 vents, semi-enclosed lagoons and mangrove estuaries are unique study...

The advent of high throughput sequencing technologies provides an opportunity to resolve phylogenetic relationships among closely related species. By incorporating hundreds to thousands of unlinked loci and single nucleotide polymorphisms (SNPs), phylogenomic analyses have a far greater potential to resolve species boundaries than approaches that r...

Modern systematics integrating molecular and morphological data has greatly improved our understanding of coral evolutionary relationships during the last two decades and led to a deeply revised taxonomy of the order Scleractinia. The family Merulinidae (Cnidaria: Scleractinia) was recently subjected to a series of revisions following this integrat...

Anomalous heat waves are causing a major decline of hard corals around the world and threatening the persistence of coral reefs. There are, however, reefs that had been exposed to recurrent thermal stress over the years and whose corals appeared tolerant against heat. One of the mechanisms that could explain this phenomenon is local adaptation, but...

Accurate delimitation of species and their relationships is a fundamental issue in evolutionary biology and taxonomy and provides essential implications for conservation management. Scleractinian corals are difficult to identify because of their ecophenotypic and geographic variation and their morphological plasticity. Furthermore, phylogenies base...

Zanclea divergens is a tropical hydrozoan living in symbiotic association with bryozoans and currently reported from Papua New Guinea, Indonesia, and Maldives. Here, we used an integrative approach to assess the morpho-molecular diversity of the species across the Indo-Pacific. Phylogenetic and species delimitation analyses based on seven mitochond...

Anomalous heat waves are causing a major decline of hard corals around the world and threatening the persistence of coral reefs. There are, however, reefs that had been exposed to recurrent thermal stress over the years and whose corals appeared tolerant against heat. One of the mechanisms that could explain this phenomenon is local adaptation, but...

Coral reef biodiversity is dominated by invertebrates, many of which are involved in symbiotic associations. The study of these relationships has led scientists to investigate possible coevolution events among the organisms involved. Despite the increasing interest in coevolution patterns, studies of marine coevolutionary events between invertebrat...