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Two new species of cornutan stylophora of the genus Phyllocystis are described from the Volkhov Regional Stage (Middle Ordovician, Dapingian) of Baltica. This indicates a biogeographic connection between the Afro-European part of Gondwana and Baltica since the very beginning of the Middle Ordovician. Both species were confined to cold-water, shallow basins with low water mobility. Analysis of the axial symmetry of stylophorans and the location of the hydropore indicates the absence of torsion in their ontogeny and the location of the ambulacral system to the right of their anteroposterior axis. To explain this morphology, two alternative hypotheses are proposed: (1) inversion in the development of right and left coeloms; (2) inverted state of stylophorans compared to other invertebrates, in which respect they resemble chordates in terms of the position of the dorsal and ventral sides. [ABSTRACT FROM AUTHOR]

Exceptional fossils preserve non-biomineralized tissues in the geological record and provide crucial information on the evolution of life on Earth. Exceptionally preserved fossils are rarely discovered complete, challenging their morphological description and their palaeontological interpretation. Although decay experiments reconstructing degradation sequences in modern animals are necessary to better understand taphonomic processes involved in exceptional preservation, their applicability to some enigmatic and/or extinct fossil taxa remains limited. Here, based on a representative sample of 423 specimens collected from a single stratigraphic level from the Early Ordovician Fezouata Biota, we reconstruct the degradation sequence of both skeletal remains and soft tissues of stylophorans, an extinct clade of echinoderms. The rare preservation of the water vascular system can be explained by the rapid post-mortem opening of the cover plates resulting from the fast decay of associated muscles and the action of ligaments. In contrast, the proximal aulacophore and associated stylocone formed a particularly decay-resistant closed module, thus favouring the preferential preservation of included soft parts (fore-gut). The non-random location and frequency of pyritised intra-skeletal structures strongly suggest that skeletal elements dictated the preservation of underlying soft parts. As such, taphonomic investigations should not only focus on the environment surrounding a decaying animal, but also on the different environments created within a particular carcass. [ABSTRACT FROM AUTHOR]

The mid-Ordovician mitrocystitid mitrate Mitrocystella incipiens was one of the most widespread stylophorans in the high latitude Mediterranean Province, with occurrences in the Armorican Massif (France), the Iberian Peninsula (Portugal and Spain) and the Prague Basin (Czech Republic), all restricted so far to the late Darriwilian (Hustedograptus teretiusculus Zone). The description of this taxon in the Corréjou Member (Postolonnec Formation) of the Crozon Peninsula (western Brittany, France) not only extends its spatial distribution within the Armorican Massif, but also its stratigraphic range into the mid-Darriwilian (Didymograptus artusZone). The remarkable preser­vation of the new material and associated sedimentological evidence both suggest rapid burial by storm deposits.

Spherulites are radial distributions of acicular crystals, common in biogenic, geologic, and synthetic systems, yet exactly how spherulitic crystals nucleate and grow is still poorly understood. To investigate these processes in more detail, we chose scleractinian corals as a model system, because they are well known to form their skeletons from aragonite (CaCO3) spherulites, and because a comparative study of crystal structures across coral species has not been performed previously. We observed that all 12 diverse coral species analyzed here exhibit plumose spherulites in their skeletons, with well-defined centers of calcification (CoCs), and crystalline fibers radiating from them. In 7 of the 12 species, we observed a skeletal structural motif not observed previously: randomly oriented, equant crystals, which we termed "sprinkles". In Acropora pharaonis, these sprinkles are localized at the CoCs, while in 6 other species, sprinkles are either layered at the growth front (GF) of the spherulites, or randomly distributed. At the nano- and micro-scale, coral skeletons fill space as much as single crystals of aragonite. Based on these observations, we tentatively propose a spherulite formation mechanism in which growth front nucleation (GFN) of randomly oriented sprinkles, competition for space, and coarsening produce spherulites, rather than the previously assumed slightly misoriented nucleations termed "non-crystallographic branching". Phase-field simulations support this mechanism, and, using a minimal set of thermodynamic parameters, are able to reproduce all of the microstructural variation observed experimentally in all of the investigated coral skeletons. Beyond coral skeletons, other spherulitic systems, from aspirin to semicrystalline polymers and chocolate, may also form according to the mechanism for spherulite formation proposed here. STATEMENT OF SIGNIFICANCE: Understanding the fundamental mechanisms of spherulite nucleation and growth has broad ranging applications in the fields of metallurgy, polymers, food science, and pharmaceutical production. Using the skeletons of reef-building corals as a model system for investigating these processes, we propose a new spherulite growth mechanism that can not only explain the micro-structural diversity observed in distantly related coral species, but may point to a universal growth mechanism in a wide range of biologically and technologically relevant spherulitic materials systems.

The mid-Ordovician mitrocystitid mitrate Mitrocystella incipiens was one of the most widespread stylophorans in the high latitude Mediterranean Province, with occurrences in the Armorican Massif (France), the Iberian Peninsula (Portugal and Spain) and the Prague Basin (Czech Republic), all restricted so far to the late Darriwilian (Hustedograptus teretiusculus Zone). The description of this taxon in the Corréjou Member (Postolonnec Formation) of the Crozon Peninsula (western Brittany, France) not only extends its spatial distribution within the Armorican Massif, but also its stratigraphic range into the mid-Darriwilian (Didymograptus artusZone). The remarkable preser­vation of the new material and associated sedimentological evidence both suggest rapid burial by storm deposits. [ABSTRACT FROM AUTHOR]

Despite being exposed to extreme water temperatures and solar irradiances, Red Sea corals are relatively resistant to bleaching. While their thermal tolerance is well described, little is known about their resistance to ultraviolet-B radiation (UVB). Here, we performed a short-term (2 days) UVB-removal incubation with Stylophora pistillata, and in situ measurements with Pocillopora verrucosa complemented by a long-term (46 days) transplantation and UVB-removal experiment. Using a suite of physiological parameters (effective quantum yield (Fv’/Fm’), oxidative stress (lipid peroxidation, LPO), and primary production), we assessed the impacts of UVB on the physiology and acclimation capacity of Red Sea corals. Shielding S. pistillata from UVB did not change the gross primary production or Fv’/Fm’, and respiration and LPO in the host remained unaffected. In situ, P. verrucosa exhibited less varying and significantly higher Fv’/Fm’ in 8 m depth (0.61 ± 0.04) than in 4 m (0.52 ± 0.06), 2 m (0.51 ± 0.09), and 0.5 m (0.50 ± 0.11), where water temperatures ranged from 30.5–33.4, 30.6–34.0, 30.8–34.5, 30.6–37.3°C and daily UVB exposures averaged 0.9, 2.9, 11.8 and 21.4 kJ m-2, respectively. Fv’/Fm’ correlated the strongest with UVB (-0.57), followed by PAR (-0.54) and temperature (-0.40), suggesting that UVB is a key determinant of photosynthetic efficiency. Fv’/Fm’ of upward transplanted specimens (T 1m) was initially decreased but gradually increased and reached the same values as shallow corals (1 m) after 44 days. UVB removal significantly increased the Fv’/Fm’ of transplanted corals in the first 20 days. Oxidative stress was initially highest in T 1m samples under full sunlight but equalized with 1 m specimens by day 46, whereas oxidative stress was significantly reduced by day 4 in T 1m corals sheltered from UVB. Overall, UVB-removal generally had little impact on the physiology of shallow-water S. pistillata and P. verrucosa but considerably accelerated the acclimation of upward transplanted corals. Our study highlights that UVB is a crucial stressor governing the photoacclimation capacity of these Red Sea coral species.

Canopies of branching corals harbor a wide range of sessile- and mobile-dwelling species that benefit from the physical compartments and the micro-environments created by the complex three-dimensional structures. Although different compartments within canopies are differentially used by inhabitant species, the distribution of mobile animals between coral canopy compartments are not fully explored. Here, we study Stylophora pistillata, a common branching coral in the Gulf of Eilat that harbors obligatory crabs from the family Trapezia. Two in situ surveys elucidated diel dynamics in compartmental distributions of Trapezia species within S. pistillata canopies compartments, associated with the crab's body size and day/night activities. Whereas all crabs were found within sheltered spaces in the coral canopy understory or in the base during day hours, laboratory experiments revealed that nighttime distributions of small and large crabs (in middle and up compartments, respectively) are not intraspecific competition-borne, but rather, the outcome of preferred crab-size location for a novel feeding type, predation on demersal plankton. This study, thus, disclosed the importance of studying the coral's three-dimensional structures and within canopies' compartments for understanding the biology of dwelling species in the animal forests' canopies. [ABSTRACT FROM AUTHOR]

Deuterostomes comprise three phyla with radically different body plans. Phylogenetic bracketing of the living deuterostome clades suggests the latest common ancestor of echinoderms, hemichordates and chordates was a bilaterally symmetrical worm with pharyngeal openings, with these characters lost in echinoderms. Early fossil echinoderms with pharyngeal openings have been described, but their interpretation is highly controversial. Here, we critically evaluate the evidence for pharyngeal structures (gill bars) in the extinct stylophoran echinoderms Lagynocystis pyramidalis and Jaekelocarpus oklahomensis using virtual models based on high-resolution X-ray tomography scans of three-dimensionally preserved fossil specimens. Multivariate analyses of the size, spacing and arrangement of the internal bars in these fossils indicate they are substantially more similar to gill bars in modern enteropneust hemichordates and cephalochordates than to other internal bar-like structures in fossil blastozoan echinoderms. The close similarity between the internal bars of the stylophorans L. pyramidalis and J. oklahomensis and the gill bars of extant chordates and hemichordates is strong evidence for their homology. Differences between these internal bars and bar-like elements of the respiratory systems in blastozoans suggest these structures might have arisen through parallel evolution across deuterostomes, perhaps underpinned by a common developmental genetic mechanism. [ABSTRACT FROM AUTHOR]

Two new mitrate stylophorans are described from the upper part of the Santa Rosa Formation (Lochkovian) in the Central Subandean Zone of Bolivia and from the Jupiter Formation (Cybèle Member, late Llandovery) of Anticosti Island (Canada). Both stylophorans are identified as allanicytidiine anomalocystitids. The new Bolivian mitrate, Perikefalea racheboeufi gen. and sp. nov. is characterized by a strongly reduced number of plates (five) on its upper thecal surface and a strong spike on its posterior median marginal. The morphology of P. racheboeufi suggests relatively strong affinities with Occultocystis, from the Lower Devonian Talacasto Formation of Argentina. Although incompletely preserved, the Anticosti mitrate, Perikefalea? cybeleae sp. nov., represents the first stylophoran described in the Silurian of North America and the first report of post-Ordovician Allanicytidiinae outside of (peri) Gondwanan regions. Skeletal homologies in mitrates (marginals, infracentrals, posterior spines, adorals, supracentrals) are reevaluated, so as to describe the plate pattern of Perikefalea. This revision was prompted by new fossil evidence from the Furongian–Tremadocian interval suggesting that (1) mitrates derive from "Phyllocystis" jingxiensis-like cornutes with wide marginals, a posteriorly open marginal frame (loss of M5 and ), a zygal plate in central position, and confluent, sutured M3 and G; (2) anomalocystitids derive from Mitrocystites-like mitrocystitidans by modification of two marginals (digital and glossal) into posterior spines. Two distinct terminologies are tentatively proposed for supracentrals in Allanicytidiinae and Anomalocystitinae, because the highly standardized plate patterns of their Siluro-Devonian representatives were possibly acquired independently in the two clades. [ABSTRACT FROM AUTHOR]

Canopies of branching corals harbor a wide range of sessile- and mobile-dwelling species that benefit from the physical compartments and the micro-environments created by the complex three-dimensional structures. Although different compartments within canopies are differentially used by inhabitant species, the distribution of mobile animals between coral canopy compartments are not fully explored. Here, we study Stylophora pistillata, a common branching coral in the Gulf of Eilat that harbors obligatory crabs from the family Trapezia. Two in situ surveys elucidated diel dynamics in compartmental distributions of Trapezia species within S. pistillata canopies compartments, associated with the crab’s body size and day/night activities. Whereas all crabs were found within sheltered spaces in the coral canopy understory or in the base during day hours, laboratory experiments revealed that nighttime distributions of small and large crabs (in middle and up compartments, respectively) are not intraspecific competition-borne, but rather, the outcome of preferred crab-size location for a novel feeding type, predation on demersal plankton. This study, thus, disclosed the importance of studying the coral’s three-dimensional structures and within canopies’ compartments for understanding the biology of dwelling species in the animal forests’ canopies.

The locomotion strategies of fossil invertebrates are typically interpreted on the basis of morphological descriptions. However, it has been shown that homologous structures with disparate morphologies in extant invertebrates do not necessarily correlate with differences in their locomotory capability. Here, we present a new methodology for analysing locomotion in fossil invertebrates with a rigid skeleton through an investigation of a cornute stylophoran, an extinct fossil echinoderm with enigmatic morphology that has made its mode of locomotion difficult to reconstruct. We determined the range of motion of a stylophoran arm based on digitized three-dimensional morphology of an early Ordovician form, Phyllocystis crassimarginata. Our analysis showed that efficient arm-forward epifaunal locomotion based on dorsoventral movements, as previously hypothesized for cornute stylophorans, was not possible for this taxon; locomotion driven primarily by lateral movement of the proximal aulacophore was more likely. Three-dimensional digital modelling provides an objective and rigorous methodology for illuminating the movement capabilities and locomotion strategies of fossil invertebrates.

Coral reefs are degrading from the effects of anthropogenic activities, including climate change. Under these stressors, their ability to survive depends upon existing phenotypic plasticity, but also transgenerational adaptation. Parental effects are ubiquitous in nature, yet empirical studies of these effects in corals are scarce, particularly in the context of climate change. This study exposed mature colonies of the common reef-building coral Stylophora pistillata from the Gulf of Aqaba to seawater conditions likely to occur just beyond the end of this century during the peak planulae brooding season (Representative Concentration Pathway 8.5: pH -0.4 and +5°C beyond present day). Parent and planulae physiology were assessed at multiple time points during the experimental incubation. After 5 weeks of incubation, the physiology of the parent colonies exhibited limited treatment-induced changes. All significant time-dependent changes in physiology occurred in both ambient and treatment conditions. Planulae were also resistant to future ocean conditions, with protein content, symbiont density, photochemistry, survival and settlement success not significantly different compared with under ambient conditions. High variability in offspring physiology was independent of parental or offspring treatments and indicate the use of a bet-hedging strategy in this population. This study thus demonstrates weak climate-change-associated carryover effects. Furthermore, planulae display temperature and pH resistance similar to those of adult colonies and therefore do not represent a larger future population size bottleneck. The findings add support to the emerging hypothesis that the Gulf of Aqaba may serve as a coral climate change refugium aided by these corals' inherent broad physiological resistance. [ABSTRACT FROM AUTHOR]

A bacterial strain, designated Sty a-1T, was isolated from a reef-building coral Stylophora sp., collected off coast of Southern Taiwan and characterized using the polyphasic taxonomy approach. Cells of strain Sty a-1T were Gram-staining-negative, aerobic, poly-β-hydroxybutyrate accumulating, motile by means of flagella, non-spore forming, straight rod-shaped and colonies were yellow and circular. Growth occurred at 15-40 °C (optimum, 30-35 °C), at pH 6-10 (optimum, pH 6.5-8) and with 0-7% NaCl (optimum, 2-3%). The predominant fatty acids were iso-C15:0, iso-C17:1ω9c, summed feature 3 (comprising C16:1ω7c and/or C16:1ω6c) and iso-C17:0. The major isoprenoid quinone was Q-8 and the DNA G+C content was 68.5 mol%. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, diphosphatidylglycerol, an uncharacterized aminophospholipid and three uncharacterized lipids. The major polyamines were spermidine, putrescine and homospermidine. Phylogenetic analyses based on 16S rRNA and four housekeeping gene sequences (recA, atpD, rpoA and rpoB) showed that strain Sty a-1T forms a distinct lineage with respect to closely related genera in the family Lysobacteraceae, most closely related to Lysobacter, Silanimonas, Arenimonas and Luteimonas and the levels of 16S rRNA gene sequence similarity with respect to the type species of related genera are less than 95%. On the basis of the genotypic and phenotypic data, strain Sty a-1T represents a novel genus and species of the family Lysobacteraceae, for which the name Coralloluteibacterium stylophorae gen. nov., sp. nov. is proposed. The type strain is Sty a-1T (= BCRC 80968T = LMG 29479T = KCTC 52167T). [ABSTRACT FROM AUTHOR]

While the early acquisition of Symbiodiniaceae algae into coral host tissues has been extensively studied, the dynamics of the migration of algal cells into rapidly expanding coral tissues still lacks a systematic study. This work examined two Red Sea branching coral species, Pocillopora damicornis and Stylophora pistillata, as they were growing and expanding their tissue laterally on glass slides (January−June, 2014; 450 assays; five colonies/species). We measured lateral tissue expansion rates and intratissue dinoflagellate migration rates. Tissue growth rates significantly differed between the two species (with Stylophora faster than Pocillopora), but not between genotypes within a species. Using a “flow-through coral chamber” under the microscope, the migration of dinoflagellates towards the peripheral edges of the expanding coral tissue was quantified. On a five-day timescale, the density of the endosymbiotic dinoflagellate cells, presenting within a 90 µm region of expanding coral tissue (outer edge), increased by a factor of 23.6 for Pocillopora (from 1.2 × 104 cells cm−2 to 2.4 × 105 cells cm−2) and by a factor of 6.8 for Stylophora (from 3.6 × 104 cells cm−2 to 2.4 × 105 cells cm−2). The infection rates were fast (5.2 × 104 and 4.1 × 104 algal cells day-1 cm−2, respectively), further providing evidence of an as yet unknown pathway of algal movement within coral host tissues.

Coral reefs are amongst the most diverse ecosystems on Earth where complex inter-specific interactions are ubiquitous. An example of such interactions is the mutualistic relationship between damselfishes and branching corals in the Northern Red Sea, where the fish use corals as shelter and provide them with nutrients, enhance the flow between their branches, and protect them from predators. By enhancing the flow between the coral branches, the fish ventilate the coral's inner zone, mitigating hypoxic conditions that otherwise develop within that zone during the night. Here, we tested, for the first time, the effects of the damselfish Dascyllus marginatus on photosynthesis and respiration in its host coral Stylophora pistillata. Laboratory experiments using an intermittent-flow respirometer showed that the presence of fish between the coral branches under light conditions augmented the coral's photosynthetic rate. No effect on the coral's respiration was found under dark conditions. When a fish was allowed to enter the inner zone of a dead coral skeleton, its respiration was higher than when it was in a live coral. Field observations indicated that damselfish were present between coral branches 18-34% of the time during daylight hours and at all times during the night. Considering the changes induced by the fish together with the proportion of time they were found between coral branches in the field, the effect of the fish amounted to an augmentation of 3-6% of the coral's daily photosynthesis. Our findings reveal a previously unknown positive contribution of coral-dwelling fish to their host's photosynthesis. [ABSTRACT FROM AUTHOR]

Corals at the world's southernmost coral reef of Lord Howe Island ( LHI) experience large temperature and light fluctuations and need to deal with periods of cold temperature (<18°C), but few studies have investigated how corals are able to cope with these conditions. Our study characterized the response of key photophysiological parameters, as well as photoacclimatory and photoprotective pigments (chlorophylls, xanthophylls, and β-carotene), to short-term (5-d) cold stress (~15°C; 7°C below control) in three LHI coral species hosting distinct Symbiodinium ITS2 types, and compared the coral-symbiont response to that under elevated temperature (~29°C; 7°C above control). Under cold stress, Stylophora sp. hosting Symbiodinium C118 showed the strongest effects with regard to losses of photochemical performance and symbionts. Pocillopora damicornis hosting Symbiodinium C100/C118 showed less severe bleaching responses to reduced temperature than to elevated temperature, while Porites heronensis hosting Symbiodinium C111* withstood both reduced and elevated temperature. Under cold stress, photoprotection in the form of xanthophyll de-epoxidation increased in unbleached P. heronensis (by 178%) and bleached Stylophora sp. (by 225%), while under heat stress this parameter increased in unbleached P. heronensis (by 182%) and in bleached P. damicornis (by 286%). The xanthophyll pool size was stable in all species at all temperatures. Our comparative study demonstrates high variability in the bleaching vulnerability of these coral species to low and high thermal extremes and shows that this variability is not solely determined by the ability to activate xanthophyll de-epoxidation. [ABSTRACT FROM AUTHOR]

Marked shifts in the composition of coral assemblages are occurring at many locations, but it is unknown whether these are permanent shifts reinforced by patterns of population replenishment. This study examined the composition of juvenile coral assemblages across the United Arab Emirates (UAE). Densities of juvenile corals varied significantly among locations, but were highest where coral cover was highest. Juvenile coral assemblages within the Persian Gulf were dominated by Porites , while no Acropora were recorded. We expect therefore, continued declines in Acropora abundance, while observed dominance of Porites is likely to persist. In the Oman Sea, Pocillopora was the dominant juvenile coral, with Acropora and Stylophora also recorded. This study shows that taxonomic differences in replenishment are reinforcing temporal shifts in coral composition within the southern Persian Gulf, but not in the Oman Sea. Differences in environmental conditions and disturbance regimes likely explain the divergent responses between regions. [ABSTRACT FROM AUTHOR]

Reef coral calcification depends on regulation of pH in the internal calcifying fluid (CF) in which the coral skeleton forms. However, little is known about calcifying fluid pH (pHCF) regulation, despite its importance in determining the response of corals to ocean acidification. Here, we investigate pHCF in the coral Stylophora pistillata in seawater maintained at constant pH with manipulated carbonate chemistry to alter dissolved inorganic carbon (DIC) concentration, and therefore total alkalinity (AT).We also investigate the intracellular pH of calcifying cells, photosynthesis, respiration and calcification rates under the same conditions. Our results show that despite constant pH in the surrounding seawater, pHCF is sensitive to shifts in carbonate chemistry associated with changes in [DIC] and [AT], revealing that seawater pH is not the sole driver of pHCF. Notably, when we synthesize our results with published data, we identify linear relationships of pHCF with the seawater [DIC]/[H+] ratio, [AT]/ [H+] ratio and [CO32- ]. Our findings contribute new insights into the mechanisms determining the sensitivity of coral calcification to changes in seawater carbonate chemistry, which are needed for predicting effects of environmental change on coral reefs and for robust interpretations of isotopic palaeoenvironmental records in coral skeletons. [ABSTRACT FROM AUTHOR]

Stylophorans are a Palaeozoic group of non-pentamerous echinoderms, morphologically well-adapted to a benthic mode of life on soft sediment seafloors. By developing a thin and wide theca, they successively increased the surface area in contact with the substrate resulting in an even distribution of the body mass resting on the ground, and efficiently preventing the body from sinking into non-indurated sediments (snowshoe strategy). In stylophorans, the body surface is dramatically increased in result of the expansion of two integumentary areas on the lower thecal surface. While infracentral areas are reduced in primitive forms to the detriment of massive marginals; in boot-shape cornutes, infracentral areas are larger, polyplated and framed by very delicate marginals. In heart-shaped cornutes, the reduction of both infracentral areas is compensated by the development of spiny elements on the theca outline. In forms where the degree of bilateral symmetry is high, the left infracentral area is larger than the right area, resulting in an elongated thecal shape. In structural geology, changes of shape of a rock submitted to a strain can be categorized by translating the obtained deformation into a strain ellipsoid plotted on a Flinn diagram, while in biology changes of shapes of organisms are traditionally measured through morphometric analysis. By applying Flinn's principle of strain ellipsoid to biological objects, the present study aims to characterize different life adaptations across stylophorans, observing changes of shape of both infracentral areas interpreted as two ellipsoids. Once plotted on a Flinn diagram, three significantly separated clusters are observed when focusing on the left area. This concerns forms with reduced infracentral areas, highly and weakly asymmetrical forms. According to these results, three new morphological adaptations are described (water strider, flat fish and stream-lined body). These newly described adaptations enabled snowshoe strategist stylophorans to remain stable on top of the seafloor. [ABSTRACT FROM AUTHOR]

Corals acquire nutrients via the transfer of photosynthates by their endosymbionts (autotrophy), or via zooplankton predation by the animal (heterotrophy). During stress events, corals lose their endosymbionts, and undergo starvation, unless they increase their heterotrophic capacities. Molecular mechanisms by which heterotrophy sustains metabolism in stressed corals remain elusive. Here for the first time, to the best of our knowledge, we identified specific genes expressed in heterotrophically fed and unfed colonies of the scleractinian coral Stylophora pistillata, maintained under normal and lightstress conditions. Physiological parameters and gene expression profiling demonstrated that fed corals better resisted stress than unfed ones by exhibiting less oxidative damage and protein degradation. Processes affected in lightstressed unfed corals (HLU), were related to energy and metabolite supply, carbohydrate biosynthesis, ion and nutrient transport, oxidative stress, Ca2+ homeostasis, metabolism and calcification (carbonic anhydrases, calcium-transporting ATPase, bone morphogenetic proteins). Two genes (cp2u1 and cp1a2), which belong to the cytochrome P450 superfamily, were also upregulated 249 and 10 times, respectively, in HLU corals. In contrast, few of these processes were affected in light-stressed fed corals (HLF) because feeding supplied antioxidants and energetic molecules, which help repair oxidative damage. Altogether, these results show that heterotrophy helps prevent the cascade of metabolic problems downstream of oxidative stress. [ABSTRACT FROM AUTHOR]

Nearly all coral reefs bordering nations have experienced net losses in reef biodiversity, goods and services, even without considering the ever-developing global change impacts. In response, this overview wishes to reveal through prospects of active reef-restoration, the currently non-marketed or poorly marketed reef services, focusing on a single coral species ( Stylophora pistillata ). It is implied that the integration of equity capitals and other commodification with reef-restoration practices will improve total reef services. Two tiers of market-related activities are defined, the traditional first-tier instruments (valuating costs/gains for extracting tradable goods and services) and novel second-tier instruments (new/expanded monetary tools developed as by-products of reef restoration measures). The emerging new suite of economic mechanisms based on restoration methodologies could be served as an incentive for ecosystem conservation, enhancing the sum values of all services generated by coral reefs, where the same stocks of farmed/transplanted coral colonies will be used as market instruments. I found that active restoration measures disclose 12 classes of second-tier goods and services, which may partly/wholly finance restoration acts, bringing to light reef capitalizations that allow the expansion of markets with products that have not been considered before. The degree to which the second tier of market-related services could buffer coral-reef degradation is still unclear and would vary with different reef types and in various reef restoration scenarios; however, reducing the uncertainty associated with restoration. It is expected that the expansion of markets with the new products and the enhancement of those already existing will be materialized even if reef ecosystems will recover into different statuses. [ABSTRACT FROM AUTHOR]

In the gardening approach for reef restoration, coral stocks are farmed in underwater nurseries (phase I) prior to their transplantation onto degraded reefs (phase II). The phase I aspects were already evaluated in the literature, but very little is known about the phase II outcomes. Assessing phase II feasibility, we transplanted 554 nursery-farmed colonies of two branching species ( Stylophora pistillata, Pocillopora damicornis ) onto five denuded knolls in Eilat (Red Sea). The performance of the transplants was compared for 17 months with 76 natal colonies and 217 colonies maintained at the coral-nursery. At the natural reef, rates of full/partial mortalities, detachment and fish herbivory were considerably higher than the nursery values. While corallivory on Pocillopora transplants was comparable to that observed in natal colonies, herbivory on Stylophora transplants increased 2.2 fold compared to natal controls. Their survivorship was similar to the survivorship observed in natal colonies in the 9 months post transplantation, but was 30% higher after 17 months. In contrast, no enhanced mortality was documented in Pocillopora transplants throughout the entire period. The detachment levels of the Stylophora and Pocillopora transplants were 3 and 10 times higher, respectively, than those observed in natal colonies, and the growth rates of the transplants were identical to the rates observed in the nursery control groups. Transplants showed a 2.5–3.3 fold increase in colonial ecological-volumes, resulting in enhanced acquired space/habitats for coral-dwelling species like Trapezia , Alpheus , Spirobranchus and Lithophaga . The successful integration of farmed transplants in Eilat’s degraded reef and their provision of new ecological niches for reef-associated fauna, coupled with economic assessments, indicate that transplantation of farmed corals is an easy, cost-effective mean to counteract degradation of coral reefs. Results also imply that the selection of coral species for reef restoration should take into consideration their autogenic/allogenic engineering properties, particularly if the aims are to restore the whole reef community, rather than simply focus on coral coverage. [ABSTRACT FROM AUTHOR]

Changing light environments force photoautotroph cells, including coral symbionts, to acclimate to maintain photosynthesis. Photosystem II (PSII) is subjected to photoinactivation at a rate proportional to the incident light, and cells must adjust their rates of protein repair to counter this photoinactivation. We examined PSII function in the coral symbiont Symbiodinium to determine the effect of photoacclimation on their capacity for PSII repair. Colonies of the coral Stylophora pistillata were collected from moderate light environments on the Lizard Island reef (Queensland, Australia) and transported to a local field station, where they were assigned to lower or higher light regimes and allowed to acclimate for 2 weeks. Following this photoacclimation period, the low-light acclimated corals showed greater symbiont density, higher chlorophyll per symbiont cell, and higher photosystem II protein than high-light acclimated corals did. Subsequently, we treated the corals with lincomycin, an inhibitor of chloroplastic protein synthesis, and exposed them to a high-light treatment to separate the effect of de novo protein synthesis in PSII repair from intrinsic susceptibility to photoinactivation. Low-light acclimated corals showed a sharp initial drop in PSII function but inhibition of PSII repair provoked only a modest additional drop in PSII function, compared to uninhibited corals. In high-light acclimated corals inhibition of PSII repair provoked a larger drop in PSII function, compared to uninhibited high-light corals. The greater lincomycin effects in the corals pre-acclimated to high-light show that high-light leads to an increased reliance on the PSII repair cycle. [ABSTRACT FROM AUTHOR]

Abstract: Ex situ aquaculture of scleractinian corals is considered as a sustainable solution to fulfill the growing demand of these highly priced organisms by the marine aquarium industry. The economic feasibility of ex situ coral aquaculture is strongly dependent on the trade-offs achieved between coral production and energy costs, namely those directly resulting from the need to employ artificial lighting systems. In the present study, we hypothesize that light spectrum can influence the growth performance of cultured scleractinian corals when these are exposed to identical photosynthetically active radiation (PAR) intensities. To test our hypothesis we evaluated the effect of contrasting light spectra delivering an identical PAR of 250±10μmol quanta m−2 s−1emitted by T5 fluorescent lamps (used as a control treatment), Light Emitting Plasma (LEP) and Light Emitting Diode (LED) on the photobiology, growth, and protein concentration of two commercially important scleractinian corals: Acropora formosa and Stylophora pistillata. Replicated coral fragments of both species were exposed to the three types of illumination for a period of 5months after which the following features were determined: maximum quantum yield of PSII (Fv/Fm ) (monitored non-intrusively through Pulse Amplitude Modulation fluorometry, PAM), chlorophyll a content (also determined non-destructively by using the spectral reflectance index Normalized Difference Vegetation Index, NDVI), growth and protein content. Coral fragments of both species cultured under LEP lighting, presented significantly higher values of Fv/Fm when compared intraspecifically with coral fragments cultured with T5 or LED lighting. Fragments of S. pistillata cultured under LEP illumination presented significantly higher NDVI values than fragments grown with T5 or LED. No significant differences were found on the protein concentration of A. formosa under different light treatments, while fragments of S. pistillata grown with LED illumination presented a significantly higher concentration of protein than those cultured with T5 or LEP illumination. Both LED and LEP technologies have shown to be interesting alternatives to provide artificial lighting for coral aquaculture ex situ, with the blue light spectrum of LED promoting high growth performances for both coral species and a lower energetic cost per m2 of production area (0.71€m−2 day−1 for T5, 0.38€m−2 day−1 for LEP, and 0.28€m−2 day−1 for LED). [Copyright &y& Elsevier]

Introduction. Corals offer hundreds of species to sea life aquarists, a market that has growth beyond the sustainable limits jeopardizing many species worldwide, mainly due to extractive activities. There is, however, an advantage in the fact that corals can be grown in re-circulation systems. Growth tests for these types of corals have not been reported in Colombia. The phylum Cnidiaria and the Anthozoa species include more than 9000 types with several reproductive strategies, from the asexual to the sexual one. Hard corals, such as Stylophora and Acropora, belong to the Hexacoralia sub-species. Objective. Measure the growth of Stylophora and Acropora species within a closed system. Materials and Methods. A 760 litters system, completed with a biological and mechanic type filtration system with Skimmer Bubble King® (240 Litters), was used to maintain three colonies of the aforementioned species. The growth of the corals was registered and the following parameters were controlled throughout a six months period: quality of the water, pH, salinity, calcium, magnesium, alkalinity, ORP, PAR, ammonia and nitrites. Results. Acropora millepora (red and green varieties), obtained the same values in the length and number of ramifications registrations at the end of the experiment: 22 centimeters and 25 ramifications, respectively. For Stylophora, the final length from the base to the apex of the fragment was 26 centimeters and the number of ramifications at the end of the experiment was 25. The water quality parameters were all within the comfort ratios for the species studied. [ABSTRACT FROM AUTHOR]

The widely distributed brooding coralStylophora pistillata(Esper 1797) occurs in the Red Sea over eastern Africa to Madagascar and the Indo-Pacific and represents a popular model system in investigating cnidarian–algal symbiosis. Recent morphological and genetic evidence suggested thatStylophoraconsists of multiple cryptic species discernible only by means of genetic techniques. We infer phylogenies from nuclear (Hsp70 gene) and mitochondrial (ORF, CR) DNA regions to explore genetic homogeneity in colonies collected asStylophora pistillataalong the Great Barrier Reef and the Coral Sea from geographically disjointed populations. Lack of phylogenetic structure among sampling sites was recovered, corroborating one genetically homogeneous species and highly connected populations. Our results provide a preliminary assessment of intra-specific genetic variability, useful for delineating taxonomical units withinStylophora pistillatain the study area. This approach is becoming increasingly important when investigating transcriptomic responses of broader physiological processes at the species level, for example, a coral's response to oxidative stress. [ABSTRACT FROM AUTHOR]

Zinc (Zn) is an essential element for corals. We investigated the effects of ocean acidification on zinc incorporation, photosynthesis, and gross calcification in the scleractinian coral Stylophora pistillata. Colonies were maintained at normal pH (8.1) and at two low-pH conditions (7.8 and 7.5) for 5 weeks. Corals were exposed to Zn dissolved in seawater to assess uptake rates. After 5 weeks, corals raised at pH (8.1) exhibited higher Zn activity in the coral tissue and skeleton, compared with corals raised at a lower pH. Photosynthesis, photosynthetic efficiency, and gross calcification, measured by Ca incorporation, were however unchanged even at the lowest pH. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyls (PCBs) are a group of widespread contaminants, and accumulation of PCBs has been observed in corals in the field. However, the toxic effects of PCBs on corals have not been investigated. In this study, we tested short and long term toxicity of Aroclor 1254, a commercial PCB mixture, on the scleractinian coral Stylophora pistillata. Coral nubbins were incubated in either control seawater or seawater dosed with PCBs (approximately 300ng/L) for 96h. The effect of PCB exposure on coral gene expression at 4h post exposure was tested with the suppression subtractive hybridization (SSH) and quantitative PCR methods. Photosystem II activity of the zooxanthellae was measured at 96h. After the exposure, nubbins were moved into clean seawater and their survival and growth were observed for another 50 days. All nubbins survived during the exposure and the following 50-d recovery period. Photosystem II activity and coral growth were not affected by PCB exposure in this study. Fifty-four clones were sequenced for gene expression analysis, and 15% of these sequences were identified, including genes involved in general stress response, peptide metabolism, cellular receptor, cytoskeleton organization, membrane trafficking, and oxidative stress response. However, the quantitative PCR did not show significant difference in the five selected genes. In conclusion, acute exposure of S. pistillata to Aroclor 1254 at 300ng/L did not affect coral survival, photosynthesis or growth but may alter the expression of certain genes involved in various important cellular functions. The nubbin technique proved to be an efficient approach to simultaneously characterize the impact of PCBs on the corals at multiple biological levels. [Copyright &y& Elsevier]

Abstract: Long-term phosphate enrichments (0, 0.5, and 2.5μmolL−1; 4 to 11weeks) were used to assess a possible limitation in phosphorus of zooxanthellae and to complement data on the effect of phosphate enrichment on calcification and elemental composition of the tissue in the scleractinian coral Stylophora pistillata. Phosphate addition mainly affected the coral symbionts. Indeed, at 2.5μmolL−1 P-enriched, zooxanthellae had a greater photosynthetic efficiency, their intracellular carbon and nitrogen contents increased by 70% and their phosphorus content by 190%, while their specific growth rate increased by 18%. C:P and N:P ratios in zooxanthellae were much higher than the Redfield ratios advocated for nutrient-repleted phytoplankton, and decreased with phosphate enrichment. Collectively, these results suggest a phosphorus limitation of the zooxanthellae growth in hospite. However, the increase in zooxanthellae specific growth rate did not lead to the building of a higher symbiont density, as zooxanthellae growth just matched the tissue and skeletal growth of the enriched corals. Benefits of phosphate supplementation were thus not substantial enough to lead to the building of higher zooxanthellae density and to their balanced growth, which suggests that symbiont growth was likely limited by another nutrient as well, probably nitrogen. At the host level, there were no changes in the elemental composition or in the protein levels, while skeletal growth rate increased by 31% between unenriched and 2.5μmol L−1 P-enriched corals. Phosphate-enriched corals also incorporated 1.7 times more phosphorus into their skeleton than did unenriched corals. These results evidenced that zooxanthellae and the skeleton are the two accumulation sites of inorganic phosphorus within the symbiotic association. [Copyright &y& Elsevier]

A combined morphological and genetic study of the coral genus Stylophora investigated species boundaries in the Gulf of Aden, Yemen. Two mitochondrial regions, including the hypervariable IGS9 spacer and the control region, and a fragment of rDNA were used for phylogenetic analysis. Results were compared by multivariate analysis on the basis of branch morphology and corallite morphometry. Two species were clearly discriminated by both approaches. The first species was characterised by small corallites and a low morphological variability and was ascribed to a new geographical record of Stylophora madagascarensis on the basis of its phylogenetic distinction and its morphological similarity to the type material. The second species was characterised by larger corallite size and greater morphological variability and was ascribed to Stylophora pistillata. The analysis was extended to the intrageneric level for other S. pistillata populations from the Red Sea and the Pacific Ocean. Strong internal divergence was evident in the genus Sty lophora. S. pistillata populations were split into two highly divergent Red Sea/Gulf of Aden and western Pacific lineages with significant morphological overlap, which suggests they represent two distinct cryptic species. The combined use of morphological and molecular approaches, so far proved to be a powerful tool for the re-delineation of species boundaries in corals, provided novel evidence of cryptic divergence in this group of marine metazoans. [ABSTRACT FROM AUTHOR]

Coral responses to degrading water quality are highly variable between species and depend on their trophic plasticity, acclimatization potential, and stress resistance. To assess the nutritional status and metabolism of the common scleractinian coral, Stylophora subseriata, in situ experiments were carried along a eutrophication gradient in Spermonde Archipelago, Indonesia. Coral fragments were incubated in light and dark chambers to measure photosynthesis, respiration, and calcification in a number of shallow reefs along the gradient. Chlorophyll a (chl a), protein content, maximum quantum yield ( F/ F), and effective quantum yield (Φ PS II) were measured on the zooxanthellae, in addition to host tissue protein content and biomass. Photosynthetic rates were 2.5-fold higher near-shore than mid-shelf due to higher areal zooxanthellae and chl a concentrations and a higher photochemical efficiency (Φ PS II). A 2- and 3-fold increase in areal host tissue protein and biomass was found, indicating a higher nutritional supply in coastal waters. Dark respiration, however, showed no corresponding changes. There was a weak correlation between calcification and photosynthesis (Pearson r = 0.386) and a lack of metabolic stress, as indicated by constant respiration and F/ F and the 'clean' and healthy appearance of the colonies in spite of high turbidity in near-shore waters. The latter suggests that part of the energetic gains through increased auto- and heterotrophy were spent on metabolic expenditures, e.g., mucus production. While coastal pollution is always deleterious to the reef ecosystem as a whole, our results show that the effect on corals may not always be negative. Thus, S. subseriata may be one of the few examples of corals actually profiting from land-based sources of pollution. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the behavior of coral assemblages after undergoing thermal stress events for 14 years in 1997-2010. It claims that extreme thermal stresses resulted in wide-ranging coral bleaching, mortality and significant shifts in coral community structure. In the study, the researchers examined if the winning species in the short term is also a winner in the long term. The different types of corals are cited including those with branched and corymbose growth forms like Acropora, Pocillopora, and Stylophora,

Abstract: We are interested in deciphering the mechanisms for morphogenesis in the Red Sea scleractinian coral Stylophora pistillata with the help of mathematical models. Previous mathematical models for coral morphogenesis assume that skeletal growth is proportional to the amount of locally available energetic resources like diffusible nutrients and photosynthetic products. We introduce a new model which includes factors like dissolved nutrients and photosynthates, but these resources do not serve as building blocks for growth but rather provide some kind of positional information for coral morphogenesis. Depending on this positional information side branches are generated, splittings of branches take place and branch growth direction is determined. The model results are supported by quantitative comparisons with experimental data obtained from young coral colonies. [Copyright &y& Elsevier]

Abstract: The continuous worldwide degradation of coral reefs raises an urgent need for novel active restoration techniques as traditional conservation practices have failed to impede the incessant reefs'' decline. While applying the “gardening coral reefs” methodology in Eilat (Red Sea, Israel), we examined reproductive outputs of naturally-grown and outplanted, nursery-farmed Stylophora pistillata colonies from three coral-transplantation trials (November 2005, May 2007, and September 2008), along three reproductive seasons. Surprisingly, transplanted colonies showed better reproductive capacities than the natal Stylophora colonies during >4 post-transplantation years. A higher percentage of nursery-farmed colonies released planula larvae as compared to naturally-grown colonies. Gravid transplants also shed more planulae per colony, yielding significantly augmented numbers of total planulae over naturally developed S. pistillata colonies. Our results indicate that nursery-grown corals may be used to enhance reef resilience by contributing to the larval pool, forming an engineered larval dispersal instrument for reef rehabilitation. [Copyright &y& Elsevier]

Abstract: Coral reefs are declining worldwide, even though traditional reef practices continuously underlie reef protection. This calls for exploration and integration of novel restoration techniques and tools, such as the “gardening” concept. The gardening approach, which has been successfully applied in various reef sites worldwide, is based on farming coral stocks in mid-water nurseries. To date, the farming of asexually produced coral material has chiefly been studied. Here, we test the performance of a novel spat-stocking tool for planulae of Stylophora pistillata, a brooding coral species. Two prototypes of a new settlement apparatus and one original apparatus made of Petri dishes lined with preconditioned transparency (Mailer''s paper) disks had been stocked with >3730 planulae. After 96h, only 95.3% of >2080 settlers were found on the Mailer paper provided. One-month-old survivors (80.8% of initial settlements) that were kept ex situ in a flow through seawater table were detached from the papers, “transglued” onto plastic pins, and transferred to mid-water coral nursery, where the trays were covered with fitted plastic nets (1cm2 mesh) to prevent predation and detachment. Four months later, more than 89% survivorship was documented, with colonies starting to form 3D structures. We estimate that 676 person-hours would be required to create 10,000 5-month-old genotypes of equal size to small branch fragments. This novel methodology allows farming of large quantities of colonies originating from sexually produced planulae and may enhance local populations'' genetic variability within a short period. This method is inexpensive and easy to perform in remote places for incorporation in coral reef management practices. [Copyright &y& Elsevier]

Abstract: The catalytic activity and the inhibition of a new coral carbonic anhydrase (CA, EC 4.2.1.1), from the scleractinian coral Stylophora pistillata, STPCA-2, has been investigated. STPCA-2 has high catalytic activity for the physiological reaction being less sensitive to anion and sulfonamide inhibitors compared to STPCA, a coral enzyme previously described. The best STPCA-2 anion inhibitors were sulfamide, sulfamic acid, phenylboronic acid, and phenylarsonic acid (K Is of 5.7–67.2μM) whereas the best sulfonamide inhibitors were acetazolamide and dichlorophenamide (K Is of 74–79nM). Because this discriminatory effect between these two coral CAs, sulfonamides may be useful to better understand the physiological role of STPCA and STPCA-2 in corals and biomineralization processes. [ABSTRACT FROM AUTHOR]

Background: Reactive oxygen species (ROS) are thought to play a major role in cell death pathways and bleaching in scleractinian corals. Direct measurements of ROS in corals are conspicuously in short supply, partly due to inherent problems with ROS quantification in cellular systems. Methodology/Principal Findings: In this study we characterized the dynamics of the reactive oxygen species superoxide anion radical (O2-) in the external milieu of the coral Stylophora pistillata. Using a sensitive, rapid and selective chemiluminesence-based technique, we measured extracellular superoxide production and detoxification activity of symbiont (non-bleached) and aposymbiont (bleached) corals, and of cultured Symbiodinium (from clades A and C). Bleached and non-bleached Stylophora fragments were found to produce superoxide at comparable rates of 10-11-10-9 mol O2- mg protein-1 min-1 in the dark. In the light, a two-fold enhancement in O2- production rates was observed in non-bleached corals, but not in bleached corals. Cultured Symbiodinium produced superoxide in the dark at a rate of 10-18-10-16 mol O2-cell-1min-1. Light was found to markedly enhance O2- production. The NADPH Oxidase inhibitor Diphenyleneiodonium chloride (DPI) strongly inhibited O2- production by corals (and more moderately by algae), possibly suggesting an involvement of NADPH Oxidase in the process. An extracellular O2- detoxifying activity was found for bleached and non-bleached Stylophora but not for Symbiodinium. The O2- detoxifying activity was partially characterized and found to resemble that of the enzyme superoxide dismutase (SOD). Conclusions/Significance: The findings of substantial extracellular O2- production as well as extracellular O2- detoxifying activity may shed light on the chemical interactions between the symbiont and its host and between the coral and its environment. Superoxide production by Symbiodinium possibly implies that algal bearing corals are more susceptible to an internal build-up of O2-, which may in turn be linked to oxidative stress mediated bleaching. [ABSTRACT FROM AUTHOR]

Particulate organic matter (POM) and dissolved organic carbon (DOC) release by six dominant hermatypic coral genera ( Acropora, Fungia, Goniastrea, Millepora, Pocillopora and Stylophora) were measured under undisturbed conditions by laboratory incubations during four seasonal expeditions to the Northern Red Sea. In addition, the influence of environmental factors (water temperature, light availability and ambient inorganic nutrient concentrations) was evaluated. Particulate organic carbon (POC) and particulate nitrogen (PN) release were always detectable and genus-specific, with Stylophora releasing most POM (6.5 mg POC and 0.5 mg PN m−2 coral surface area h−1) during all seasons. The fire coral Millepora released significantly less POM (0.3 mg POC and 0.04 mg PN m−2 coral surface area h−1) than all investigated anthozoan genera. The average POC:PN ratio of POM released by all coral genera was 12 ± 1, indicating high carbon/low nitrogen content of coral-derived organic matter. POM release showed little seasonal variation, but average values of POC and PN release rates correlated with water temperature, light availability and ambient nitrate concentrations. DOC net release and elevated DOC:POC ratios were detectable for Acropora, Goniastrea and Millepora, revealing maximum values for Acropora (30.7 mg DOC m−2 coral surface area h−1), whilst predominant DOC uptake was observed for Pocillopora, Fungia and Stylophora. Depth-mediated light availability influenced DOC fluxes of Acropora and Fungia, while fluctuations in water temperature and ambient inorganic nutrient concentrations showed no correlation. These comprehensive data provide an important basis for the understanding of coral reef organic matter dynamics and relevant environmental factors. [ABSTRACT FROM AUTHOR]

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Abstract: The activity of the coral Stylophora pystillata secretory carbonic anhydrase STPCA has been tested in presence of amino acids and amines. All the investigated compounds showed a positive, activating effect on k cat and have been separated in weak (K A in the range of 21–126μM), medium (10.1–19μM) and strong enzyme activators (K A of 0.18–3.21μM). D-DOPA was found to be the best coral enzyme activator, with an activation constant K A of 0.18μM. This enhancement of STPCA activity, as well as previous enzyme inhibition results, might now be tested on living organisms to better understand the role played by these enzymes in the coral calcification processes. [Copyright &y& Elsevier]

Species of bacteria associated with Stylophora pistillata were determined by analyses of 16S ribosomal genes. Coral samples were taken from two distinct sites at Kenting, in the far south of Taiwan; three coral colonies at each site were tagged and sampled in the winter and summer of 2007. Six hundred 16S rRNA gene clones were selected and sequenced for diversity analysis and community comparison. LIBSHUFF and nonparametric multiple dimensional scaling analyses showed variations in the composition of the coral-associated bacteria in the different samples, suggesting that seasonal and geographic factors and variations in individual coral colonies were all vital drivers of the structure of the S. pistillata-associated bacterial community. To examine the association between species specificity and environmental impacts on the structure of the coral-associated bacterial community, we conducted an integrated, comparative analysis of 44 coral-associated bacterial data sets, including the present study's data. The clustering analysis suggests that the influence of spatial and temporal factors on the coral-associated bacteria population structure is considerable; nonetheless, the effect of species specificity is still detectable in some coral species, especially those from the Caribbean Sea. [ABSTRACT FROM AUTHOR]

Fossil carpoids possess a unique anatomy that is difficult to interpret; as a result, there are a number of competing phylogenetic hypotheses for carpoid taxa. Stratigraphic congruence indices provide a quantitative means of evaluating alternative cladograms where character coding is contentious; trees that show a statistically significant fit between stratigraphy and phylogeny are better supported by the fossil record. We here test the agreement between stratigraphic and cladistic data for 27 carpoid cladograms (24 have previously been published, three are novel). The results demonstrate that in analyses of subsets of carpoid taxa, the stratigraphic congruence of trees is not strongly affected by the interpretative model followed. However, when studying the relationships of carpoids with other deuterostomes, assuming that carpoids should be interpreted by reference to chordates/hemichordates (rather than echinoderms) leads to a poorer fit with the known stratigraphic ranges of taxa. Thus, the disputed calcichordate hypothesis (carpoids interpreted as stem and crown-group chordates and stem-group hemichordates) is much less congruent with stratigraphy than alternative models interpreting carpoids as stem or crown-group echinoderms. [ABSTRACT FROM AUTHOR]