Pentapora Fascialis Research Articles

Development of a set of SNP markers for population genetics of the sea rose, Pentapora fascialis

Development of a set of SNP markers for population genetics of the sea rose, Pentapora fascialis

Ecology, distribution and demography of erect bryozoans in Mediterranean coralligenous reefs

Coralligenous reefs are considered as one of the most important benthic ecosystems in the Mediterranean Sea in terms of biodiversity, ecosystem functioning, and aesthetic value. Bryozoans deserve special attention within the coralligenous framework fauna: they are among the most common animals, showing high diversity values and playing different functional roles. Distribution, spatial variability, and demographic features of five erect bryozoan taxa Adeonella sp., Myriapora truncata, Pentapora fascialis, Reteporella sp., and Smittina cervicornis were studied in the central Tyrrhenian Sea. Abundance, size, and relationship with other taxa/morphological groups of benthic organisms were studied in coralligenous reefs between 35 and 40 m depth. High density of colonies was reported especially in association to gorgonians and algae dominated assemblages. Size distributions of the five bryozoans were characterized by small colonies; only two species (P. fascialis and S. cervicornis) showed colonies larger than 50 cm2. Structure of coralligenous assemblages and disturbances outlined different ecological requirements of the five studied taxa. Results provide baseline information for monitoring trajectories of change of these organisms in the coralligenous ecosystem. To date, this work represents the first study exploring ecology and distribution patterns of common erect bryozoans in the Mediterranean Sea.

Assessing the effectiveness of restoration actions for Bryozoans: The case of the Mediterranean Pentapora fascialis

Abstract Marine ecosystems are highly affected by several human stressors. In this context, beyond passive restoration measures such as the creation of marine protected areas, it is urgent that we explore active restoration measures to enhance and accelerate the recovery of sessile marine species. Bryozoans are among the most common sessile invertebrates in rocky bottom ecosystems and are considered habitat‐forming species that are highly vulnerable to physical disturbances, such as recreational diving, ghost fishing nets, and global warming, which makes them highly vulnerable to other impacts. Despite their ecological importance and vulnerability, to date restoration actions for bryozoans have rarely been explored. In this study, different restoration techniques were developed and tested, with a focus on two types of effective methodologies previously applied to other marine invertebrates: recruitment enhancement and the transplantation of adult colonies, in both cases using the Mediterranean bryozoan Pentapora fascialis as a model species. First, different types of artificial surfaces were installed in different coralligenous habitats to test the enhancement of recruitment, concluding that plastic grids are the best substrate in terms of facilitating the recruitment of new bryozoan colonies. Second, different methodologies were tested for adult transplantation. The most successful was to fix colonies to a suitable substrate with a nylon thread attached to the colony ex situ (i.e. on the boat). Using this technique a trial restoration programme was undertaken, involving transplanting adult colonies collected from a ghost fishing net trapped on the bottom, which showed a high survival rate of ~50% after 6 months. The low economic cost of the implementation of the proposed techniques as well as the successful results obtained highlight the viability of restoring bryozoan populations over long temporal and spatial scales.

Unravelling the population dynamics of the Mediterranean bryozoan Pentapora fascialis to assess its role as an indicator of recreational diving for adaptive management of marine protected areas

Marine Protected Areas (MPAs) have been recognized as effective management and conservation tools to protect marine coastal ecosystems. However, due to an increasing interest in marine ecosystems, recreational activities such as scuba diving are rapidly growing in these areas, highlighting the need to implement adaptive management strategies based on continuous monitoring and evaluation of protected areas. To date, several studies have quantified the impact of diving using benthic species as indicators, such as bryozoans, but usually ignoring their population dynamics. Here, we studied the population dynamics of the abundant and common bryozoan Pentapora fascialis on a Mediterranean MPA with high levels of diving activity. Specifically, we monitored eight different localities with two different levels of diving frequentation (non-frequented versus frequented) from October 2015 to October 2018, accounting for the demographic parameters before and after the summer. Our results showed the impact of diving on the density, recruitment, survival, and size of colonies, reaching higher values on non-frequented localities. In addition, we detected two peaks of recruitment during July 2016 and July 2018, suggesting that bryozoan recruitment events are stochastic, with a high inter-annual variation. Contrastingly, regardless of the diver frequentation level, we found higher growth rates during the colder months and higher necrosis rates after the summer in all the studied localities. Besides the aforementioned differences, the densities observed in this study were much higher compared to previous studies performed in the same area during the 1990s. Taken together, these results suggested rapid population dynamics of P. fascialis, with fast growth rates and a high capacity to recover from perturbations. Despite the quantified effects of diving on our studied species, their abundance in frequented sites remained very low over the whole study period, compromising the use of P. fascialis as an optimal indicator of diving impact for adaptive management of temperate benthic populations. Overall, our results highlight the importance of continuous monitoring programs to unravel the population dynamics of indicator species to effectively manage marine populations and evaluate the impact of human activities on marine protected areas.

Divergent responses to warming of two common co-occurring Mediterranean bryozoans

Climate change threatens the structure and function of marine ecosystems, highlighting the importance of understanding the response of species to changing environmental conditions. However, thermal tolerance determining the vulnerability to warming of many abundant marine species is still poorly understood. In this study, we quantified in the field the effects of a temperature anomaly recorded in the Mediterranean Sea during the summer of 2015 on populations of two common sympatric bryozoans, Myriapora truncata and Pentapora fascialis. Then, we experimentally assessed their thermal tolerances in aquaria as well as different sublethal responses to warming. Differences between species were found in survival patterns in natural populations, P. fascialis showing significantly lower survival rates than M. truncata. The thermotolerance experiments supported field observations: P. fascialis started to show signs of necrosis when the temperature was raised to 25–26 °C and completely died between 28–29 °C, coinciding with the temperature when we observed first signs of necrosis in M. truncata. The results from this study reflect different responses to warming between these two co-occurring species, highlighting the importance of combining multiple approaches to assess the vulnerability of benthic species in a changing climate world.

Scuba diving damage on coralligenous builders: Bryozoan species as an indicator of stress

The effects of scuba diving activities on coralligenous concretions builders in the Mediterranean Sea are reported for a non-marine protected area (non-MPA). Five erect bryozoan species, which are particularly vulnerable due to their fragile structure, were investigated: Adeonella calveti, Myriapora truncata, Pentapora fascialis, Reteporella grimaldii, and Smittina cervicornis. These species were sampled at frequently and rarely visited diving sites to the maximum depths reachable with the most common recreational diving certifications (i.e., 40m). To do this, a non-destructive photographic sampling technique was used to minimize any impact on the benthic communities. For each sample, the number of colonies, their width, coverage, type of injury and degree of exposure were quantified using image analysis software. The number of species differed between the frequently and rarely visited diving sites, and frequently visited sites had significantly lower number of colonies and reduced colony width. Species-specific response to stress was associated with colony morphology and skeleton rigidity. Both the type of injury and colony position within the coralligenous habitat were affected by the presence of scuba divers. A linear model was proposed to analyse the response of bryozoans to scuba diving pressure. The results reported here suggest that P. fascialis and R. grimaldii could serve as robust species indicators of diving stress.

Amphipod community associated with invertebrate hosts in a Mediterranean marine cave

The present study explored the amphipod communities associated with the dominant host invertebrates inhabiting a marine cave of South Spain in order to describe their species composition and distribution patterns. Although they play a key role in the structure of mobile epifaunal communities inhabiting most rocky reef ecosystems, this component of marine caves communities has often been overlooked. Colonies of six sessile species were collected: Astroides calycularis, Parazoanthus axinellae, Pentapora fascialis, Aldeonella calveti, Filograna implexa, and Ircinia fasciculata. In each sample the mobile epifaunal community (mainly focusing on the amphipod group) was characterized, with Arthropoda and Amphipoda being the dominant phylum and order, respectively. Among amphipods, the gammarid Lembos websteri and the caprellids Phtisica marina and Pseudoprotella phasma were the most abundant species. The endangered coral Astroides calycularis showed the most distinctive amphipod community and multivariate analysis highlighted the existence of significant differences in the amphipod assemblages among invertebrate hosts in the cave. However, no host-specific species were found. Benthic hosts inside the cave are mainly used as a refuge by amphipods and all the sessile species studied seem to play an equivalent facilitation role. To what extent changes in the composition of sessile species may affect other associated species was also discussed.

Recovery of a Temperate Reef Assemblage in a Marine Protected Area following the Exclusion of Towed Demersal Fishing

Marine Protected Areas MPA have been widely used over the last 2 decades to address human impacts on marine habitats within an ecosystem management context. Few studies have quantified recovery of temperate rocky reef communities following the cessation of scallop dredging or demersal trawling. This is critical information for the future management of these habitats to contribute towards conservation and fisheries targets.The Lyme Bay MPA, in south west UK, has excluded towed demersal fishing gear from 206 km2 of sensitive reef habitat using a Statutory Instrument since July 2008.To assess benthic recovery in this MPA we used a flying video array to survey macro epi-benthos annually from 2008 to 2011. 4 treatments (the New Closure, previously voluntarily Closed Controls and Near or Far Open to fishing Controls) were sampled to test a recovery hypothesis that was defined as ‘the New Closure becoming more similar to the Closed Controls and less similar to the Open Controls’.Following the cessation of towed demersal fishing, within three years positive responses were observed for species richness, total abundance, assemblage composition and seven of 13 indicator taxa. Definitive evidence of recovery was noted for species richness and three of the indicator taxa (Pentapora fascialis, Phallusia mammillata and Pecten maximus).While it is hoped that MPAs, which exclude anthropogenic disturbance, will allow functional restoration of goods and services provided by benthic communities, it is an unknown for temperate reef systems. Establishing the likely timescales for restoration is key to future marine management. We demonstrate the early stages of successful recruitment and link these to the potential wider ecosystem benefits including those to commercial fisheries.

Long-term trend in substratum occupation by a clonal, carbonate bryozoan in a temperate rocky reef in times of thermal anomalies

Studies over time provide opportunities to detect variations in the spatial and temporal patterns of clonal organisms and measure changes on their population dynamics related to extreme events. We assessed population dynamics for a bryozoan species dominating a subtidal rocky reef at Tino Island, in the eastern Ligurian Sea (NW Mediterranean). Using 9 years of annual photosurveys (1997–2005), rapid decline in Pentapora fascialis colony cover was shown at 11 and 22 m depths following the anomalous warming events in 1999 and 2003. An 86 % reduction in live colony portion was found after the 1999 warming event (2.3 °C higher than normal), with larger colonies being most affected. Effects from the 2003 event were delayed, and gradual cover decline occurred during the following 2 years. At the “Shallow” photostations, none of the larger colonies (>1,000 cm2) survived after the first cover decline. Availability of new substrate after the 1999 disturbance resulted in enhanced recovery through new colony production. At the “Deep” photostations, the population structure did not change over the duration of the monitoring period showing the same monomodal structure and same dominant size class (50–500 cm²). In the 4 years following the first cover decline, the deeper population regained colony cover to levels similar to pre-disturbance level, showing a good resilience. This 9-year monitoring analysis provided the temporal resolution needed to detect changes occurring in the P. fascialis population and will contribute to the assessment of long-term changes on benthic populations suffering during recent decades from dramatic increases in extreme events.

Systematics of the Miocene-Recent bryozoan genusPentapora(Cheilostomata)

The four existing species of the ascophoran bryozoan Pentapora Fisher, 1807 are revised, and two new fossil species are introduced: Pentapora lacryma sp. nov. from the Pliocene Coralline Crag Formation of Suffolk, and Pentapora clipeus sp. nov. from the Pliocene of Emilia, Italy. The Arctic species Pentapora boreale Kuklinski & Hayward possesses a lyrula, does not belong in Pentapora, and is a junior synonym of Raymondcia rigida (Lorenz). The morphology of the autozooids is relatively uniform within the genus, and the main distinguishing characters are those of the ovicells and, particularly, the giant avicularia that are developed sporadically in all species apart from Pentapora foliacea, popularly known as ‘Ross coral’. A phylogenetic analysis based on skeletal characters returned a single shortest tree in which the three species of Pentapora from the North Atlantic (P. foliacea, Pentapora pertusa, and P. lacryma sp. nov.) form a clade crownward of the three basal species from the Mediterranean (Pentapora ottomulleriana, Pentapora fascialis, and P. clipeus sp. nov.). © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160, 17–39.

Distribution and morphological variation of colonies of the bryozoan Pentapora fascialis (Bryozoa: Cheilostomata) along the western coast of Italy

Bathymetric range, substrate, colony density, colony size, and some zoarial features (form of the colony and branches) of the carbonate reef building cheilostome bryozoan Pentapora fascialis (Pallas) were recorded from 15 localities along the western coast of Italy. A wide range in the depth distribution of colonies was observed (11 to 60 m). Colonies occurred on several different types of substrate including gorgonians, sponges, bedrock and rock boulders, in current swept areas. Density was approximately 1 colony/m2. The most frequent colony size-class was 10 to 20 cm in diameter and was typically found growing epizoically on gorgonians. Ellipsoidal colony forms with expanded, foliaceous laminae were characteristic of larger colonies; these frequently grew on rock substrates. Subspherical colonies with a diameter less than 20 cm grew as epizoans and had a narrow branches structure. This information will help to inform decisions on taxonomic discrepancies within the Pentaporidae. In addition the data provide a useful baseline for the future estimation of a carbonate budget in the region.

Differential microbial fouling on the marine bryozoan Pentapora fascialis

Marine fouling is a commercially important problem affecting abiotic and biotic surfaces. In this study we investigated the surface fouling on a colonial reef-building invertebrate, the bryozoan Pentapora fascialis, from the Welsh coast. We captured 300 scanning electron microscope (SEM) images of 5 colonies of the bryozoan P. fascialis in order to quantify the level of fouling on the exterior surfaces. Evidence for differential fouling was found to occur at several spatial scales, including between older and newer zooids, between proximal and distal regions of the same zooids and between colonies. The current year's growing zooids were found to have a higher level of fouling than older zooids. The difference in the mean level of fouling of proximal regions of zooids compared to distal regions was found to be significant in P. fascialis. In agreement with the differential fouling previously observed by other authors in the laminar bryozoan Flustra foliacea where the proximal region of a zooid was observed to have a higher level of fouling, the fouling coverage in P. fascialis was higher in the proximal region of zooids. A reduction of fouling on some bryozoan surfaces may be caused by production of antimicrobial compounds. Further studies of microbial fouling of a similar quantitative scale in other bryozoans could aid in the identification of novel antimicrobial agents useful for preventing microbial fouling on abiotic surfaces in the marine environment.

The influence of seawater temperature on zooid size and growth rate in Pentapora fascialis (Bryozoa: Cheilostomata)

Zooid size variation and growth banding in the bryozoan Pentapora fascialis, collected from the South of Great Britain to the South of Italy, were investigated in order to test their relationship with the variation of seawater temperature. Zooid length appeared to be more sensitive than zooid area and width to temperature variation. The longest zooids were budded in localities that typically experience low seasonal variation in temperature (3.2–7.5°C) and low mean annual temperature (about 11°C). Zooid length demonstrated the strongest relationship with the range of seasonal variation in temperature rather than the mean annual temperature. Growth bands produced during colder months were less high than those produced during warmer months. Measurements of these alternating bands were used to calculate growth rate of the laminae, ranging from 20.7 at Plymouth to 29.3 mm year−1 at Tino Island. Significant differences in zooid length were found between the two bands, with longer zooids within the band developed in colder months and shorter zooids in bands produced in the warmer period. We conclude that zooid size can be used as an environmental proxy of the seasonal temperature regimes experienced by the species.

Growth of the bryozoan Pentapora fascialis (Cheilostomata, Ascophora) around submarine freshwater springs in the Adriatic Sea

Growth of the bryozoan Pentapora fascialis (Cheilostomata, Ascophora) around submarine freshwater springs in the Adriatic Sea

Carbonate bioformations around underwater freshwater springs in the north-eastern Adriatic Sea

Large carbonate, bryozoan-serpulid constructions, made by Pentapora fascialis and Salmacina dysteri respectively, were found around karstic freshwater springs, called vruljas, in the Senj Archipelago (Velebit Channel, Croatia). In June 2002, several sites were investigated by SCUBA divers on the rocky cliffs of Grmac and Ždralova at depths ranging from 19 to 32 m. Mean colony diameter decreased with increasing distance from the vruljas: in the vicinity the mean diameter was 65.8±21 cm, at 2-m distance it was 40.4±8.2. Carbonate contribution was to a great extent due to the bryozoan (5,784±1,186 g⋅m−2 CaCO3) rather than to the serpulid (383±218 g⋅m−2 CaCO3). P. fascialis carbonate standing stock was remarkably high if compared with data from literature for shallow carbonate producers. The bryozoan-serpulid constructions can be indicated as important, even if localised, contributions to the carbonate budget in the Adriatic Sea.

3-D reconstruction of biological objects using underwater video technique and image processing

This paper describes a 3-D reconstruction method which allows accurate measurements of volume, surface area and other morphometric measurements of three-dimensional biological objects, without removing them from the sea. It represents a novel approach based on multiple views (eight resulted to be sufficient) from underwater video images and a new image processing procedure (MOD3D), whose application has met the basic requirements (i.e. to work on images recorded in turbid waters, with nonuniform lighting, to investigate large areas and in reasonable time, etc.) imposed when operating in the marine environment with simple, easy-to-use and nonprofessional equipment. It is a noninvasive, nondestructive and in the field fast method, thus suitable for sampling also at relevant depth, whose applicability has specifically been set up for a range of growth forms from massive to submassive and irregularly shaped. The accuracy of the method was assessed using models with three levels of 3-D complexity: simple, moderate and complex morphology. A high accuracy of volume measurements made through MOD3D image analysis software was achieved when compared with the laboratory water displacement method, which represents the most accurate method for volume measurement, with an overall mean percent error of about 1.7% (S.D. 2.2%). For all three levels of morphologic complexity, no significant differences ( p>0.05) were found. Volume measurements obtained in field based on geometric approximation resulted rough, with significant differences from the MOD3D values ( p<0.05). The geometric approximation was lower than MOD3D for simple and moderate morphology, and variable for complex morphology. For all three models, MOD3D values for surface area computation were consistently lower (mean error 13%) than the foil-wrapping values ( p<0.05), due to overlap error when foil wrapping. Two applications were made with the bryozoan Pentapora fascialis and the coral Cladocora caespitosa to quantify carbonate standing stock and biomass of these two carbonate framework builders, whose importance has been recently recognised among the temperate sublittoral benthic species. Time required for the 3-D reconstruction method (about 3 h) makes it suitable for routine application particularly for relatively large area investigations, with irregularly shaped objects on rough substrate and several biological objects within the area.

Pentaporins A, B and C: Disulfides from the Marine Bryozoan Pentapora fascialis.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Pentaporins A, B and C: disulfides from the marine bryozoan Pentapora fascialis

Three new disulfides, pentaporins A, B and C, with anthelmintic in vitro activity have been isolated from the mediterranean bryozoan Pentapora fascialis. The structures of these compounds were determined by 1D and 2D NMR spectroscopy, mass spectrometry and EDX-analysis. The pentaporins show activity against Trichinella spiralis.

Distribution patterns of the sublittoral epibenthic assemblages on a rocky shoal in the Ligurian Sea (NW Mediterranean)

Acquiring baseline data on highly diverse communities such as coralligenous ones is very valuable in order to determine possible shifts in communities and define strategies for their preservation. Distribution of sciaphilic epibenthic communities belonging to the `coralligene de la roche littorale´ was investigated at 30 photostations from 17 to 24 m depth on a rocky shoal off the island complex in the Gulf of La Spezia (Ligurian Sea, NW Mediterranean). Four communities displayed a sharp zonation: Paramuricea clavata characterised deeper, vertical surfaces, whereas on horizontal and medium inclination, sediment-covered substrata, Leptogorgia sarmentosa , together with Eunicella singularis and Eunicella verrucosa , characterised the upper stratum of the deeper community. Shallow vertical walls were characterised by a facies with sponges and zoantharians, whereas community dominated by large, massive colonies of Pentapora fascialis with a basal stratum of sciaphilic algal species patched with sediment on shallow rocky slopes of medium inclination. Bathymetric distribution of assemblages is influenced by high seawater turbidity (mean annual transparency: 11.9 ± 5.7 m at the western site, 6.2 ± 1.6 m at the eastern site), which induces a shift of the upper limit of distribution of these facies to unusually shallow depths. Quantitative data provide a baseline on the study site that will be useful to understand the influence of not only biotic and abiotic factors, but also mass-mortality events, particularly on these communities characterised by high resilience.

Carbonate standing stock and carbonate production of the bryozoanPentapora fascialis in the North-Western Mediterranean

Pentapora fascialis, one of the largest living bryozoan, is often a predominant part of the benthos on hard subtidal bottoms in the Mediterranean Sea. Conversion factors calculated from laboratory measurements of colony size, biomass and skeleton weight, combined with density of colonies and mean annual growth rate allowed the estimation of carbonate standing stock, biomass and carbonate production ofPentapora fascialis in five sites in the Ligurian Sea. Carbonate standing stock ranged from 281 to 2490 g·m−2, colony biomass varied from 8.82 to 78.01 g·m−2, with a ratio biomass to carbonate standing stock of about 3%. Carbonate production of the bryozoan ranged in the five sites from 358 to 1214 g·m−2·y−1. If compared with the few data available on carbonate production of bryozoans and other sublittoral benthic bioconstructors in the temperate regions,Pentapora fascialis has to be considered one of the major contributors to the carbonatebudget.