Sven Zea

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• Ph.D.
• Taxonomy, ecology and biotechnology of marine sponges at National University of Colombia

Introduction: Although many reefs have been disturbed by the combined effects of climatic and non-climatic stressors, there still are regions largely free from direct human pressures such as runoff, pollution, and maritime traffic due to their geographic remoteness. This suggests that they are replicas of “pristine reefs”, that allow the investigat...

A pesar de las tendencias contemporáneas de pérdida coralina generalizada, se presume, en parte por falta de información, que los arrecifes oceánicos remotos deben estar en mejor estado que los arrecifes continentales, asumiendo que por su lejanía geográfica hay un menor efecto de presiones humanas directas. Este trabajo tuvo como objetivo determin...

A pesar de las tendencias contemporáneas de pérdida coralina generalizada, se presume, en parte por falta de información, que los arrecifes oceánicos remotos deben estar en mejor estado que los arrecifes continentales, ya que su lejanía geográfica los mantendría exentos del efecto directo de presiones humanas. Por lo anterior, se buscó determinar s...

The genus Tethya, one of the most iconic groups in the phylum Porifera. includes nearly 100 valid species. Tethya shows a nearly cosmopolitan distribution, and thus this clade could help elucidate global mechanisms of speciation in sponges. Contrasting with many other marine organisms, Tethya peaks in diversity in the temperate region, with only $3...

Principales resultados de la Expedición Científica Seaflower 2021-II Isla Cayos de Bajo Nuevo. Proyecto Interacciones coral-céspedes algales y su efecto sobre la comunidad arrecifal (capitulo 5)

The biodiversity of sponges in environments beyond 50 m is poorly known, as access to this type of environment without specialized technology is difficult. This study aims to understand the biodiversity of the group present on the continental shelf of the southwestern area of Isla Fuerte and Alta Guajira. Sponge samples were collected via trawls du...

Técnicas de evaluación y monitoreo de la frecuencia y el resultado de interacciones entre corales masivos con otros organismos bentónicos en arrecifes con profundidad somera y media (< 15m), mediante las técnicas de transecto por fotocuadrante, marcaje de colonias para la estimación de la tasa anual de avance/retroceso de tejido coralino, instalaci...

Understanding nutrition and its effect on growth is essential for developing diets in commercially important species. This study aimed to evaluate the larval development of Callinectes sapidus fed with rotifers (Brachionus plicatilis) enriched with Chlorella pyrenoidosa (Ch) as a main protein source and a lipid emulsion (Spr) rich in highly unsatur...

The genus Placospongia Gray, 1867 is a group of sponges widely distributed in the world. It currently has 11 valid species, where five of those, Placospongia caribica Rützler et al., 2014, P. cristata Boury-Esnault, 1973, P. intermedia Sollas, 1888, P. ruetzleri van Soest, 2017 and P. giseleae Mácola & Menegola, 2021, are distributed in the Central...

Most of the theoretical and practical development of the ocean acidification (OA) phenomenon involves the open ocean, and not much is known of the significance of variation in pH and carbonate system in coastal environments and the effect, if any, of OA. Traditional potentiometric pH measurements are carried out on the NBS scale (pHNBS), developed...

La Cordillera submarina Beata se encuentra ubicada en el extremo nororiental del territorio marítimo de Colombia, dividiendo al Caribe en las cuencas de Colombia y Venezuela, con profundidades que van desde 1500 hasta 4400 metros. Los montes submarinos como la Cordillera Beata, se caracterizan por tener pendientes pronunciadas con sustratos duros y...

La zona batial inferior de la Cordillera Malpelo (entre 1800 y 3000 m de profundidad) es un área marina profunda sobre la cuenca del Pacífico Norte colombiano‚ con escasa información sobre su megafauna bentónica. En esta elevación marina se encuentran hábitats rocosos de interés ecológico‚ que ofrecen grandes extensiones de sustratos heterogéneos y...

La Cordillera submarina Beata se encuentra ubicada en el extremo nororiental del territorio marítimo de Colombia‚ dividiendo al Caribe en las cuencas de Colombia y Venezuela‚ con profundidades que van desde 1500 hasta 4400 metros. Los montes submarinos como la Cordillera Beata‚ se caracterizan por tener pendientes pronunciadas con sustratos duros y...

Los métodos de recolección varían dependiendo del tamaño y forma de crecimiento de las esponjas. Aquellas perforadoras de coral o que crecen a manera de incrustaciones o revestimientos muy delgados sobre rocas o litoral, deben recolectarse junto con el esqueleto calcáreo o fragmento de litoral en donde se encuentren, para mantener la estructura esq...

Most of the theoretical and practical development of the ocean acidification (OA) phenomenon involves the open ocean, and not much is known of the significance of variation in pH and carbonate system in coastal environments and the effect, if any, of OA. Traditional potentiometric pH measurements are carried out on the NBS scale (pHNBS), developed...

Chapter 12. Status and trends of coral reefs of the Caribbean region, pp. 1-25. In: Souter, D., Planes, S., Wicquart, J., Logan, M., Obura, D., & Staub, F. (Eds.) Status of Coral Reefs of the World: 2020. Global Coral Reef Monitoring Network, International Coral Reef Iniciative, Australian Institute of Marine Science, & Australian Governement.

El mar territorial colombiano, con costas en el mar Caribe y el océano Pacífico, comprende unos 2.070.408 km2, lo cual significa que cerca del 50% del territorio nacional es marítimo. A través de este libro se hace una invitación a las generaciones actuales y futuras a ejercer soberanía, defender y cuidar este bien, para conservar la biodiversidad...

ecidos y en interacción directa con corales masivos, y se relacionó su complejidad estructural con la capacidad de retención de sedimentos. Para ello, se determinó la composición taxonómica y se cuantificaron la altura del dosel, la cobertura y densidad de filamentos y la biomasa algal de los céspedes que crecían sobre colonias vivas de cuatro espe...

Compared to other groups of invertebrates, sponge (Porifera) taxonomy has been poorly developed in the Eastern Tropical Pacific (ETP) in general and in the Colombian Pacific in particular. This work aims to increase knowledge of the group’s biodiversity in the rocky reefs of northern Chocó. Sponge samples were collected by autonomous diving, which...

Las lagunas costeras son foco de producción primaria y refugio de biodiversidad por su relativo confinamiento y baja profundidad. La Escollera es una laguna costera artificial situada en El Rodadero, Santa Marta (Caribe colombiano), excavada al inicio de la década de 1980 para albergar una marina y sus bordes sembrados con mangles. Para generar una...

The book presents the results of the expeditions carried out by Invemar between 2011-2018 to the North Pacific of Chocó to study the biodiversity on the shallow portion (0-40 m deep) of the rocky reefs, locally named riscales and morros. In total, 33 sites were explored across around 200 km of coastline between Cabo Corrientes and Cabo Marzo. 59 sp...

Durante una expedición al Pacífico norte chocoano en agosto de 2015 se recolectaron muestras de esponjas en los riscales y morros entre Cabo Corrientes y Cabo Marzo, que fueron procesadas e identificadas en el laborato-rio del Invemar en Santa Marta en un trabajo conjunto entre el INVEMAR y el CECIMAR. Se identificaron 24 mor-fotipos pertenecientes...

Esta investigación buscó determinar el papel de la herbivoría por parte del caracol Cittarium pica sobre el ensamblaje algal del litoral rocoso en el área de Santa Marta, Colombia. Se realizaron experimentos con jaulas en el mesolitoral superior entre diciembre de 2017 y junio de 2018, con tratamientos de inclusión (C. pica), exclusión (sin herbívo...

Las ramas muertas de Acropora palmata colonizadas por la esponja excavadora Cliona tenuis son propensas al desplazamiento, la rotura y la translocación durante fuerte oleaje o mar de fondo de tormentas o huracanes, lo que favorece la dispersión de esta esponja. En las islas del Rosario (Colombia, Caribe), los adultos de C. tenuis transportados por...

Digital version available in: https://editorial.unimagdalena.edu.co/Editorial/Publicacion/4142

The Caribbean soft coral Erythropodium caribaeorum is a rich source of erythrolides—chlorinated briarane diterpenoids. These compounds have an ecological role as feeding deterrents, with a wide variation in their composition depending on the location where the sample is collected. In Colombia, this soft coral can be found at different locations in...

In coral reefs, competition between sessile benthic organisms for access to space and other resources is a determining factor in community structuring. Recent coral mortality has favored the development of algal turfs, which are now competing with corals, often displacing them, although slowly. To determine the frequency of interactions between cor...

Biofilm formation is an important process for marine bacterial communities because this mechanism favors adaptation to variations in environmental conditions. The objective of this study was to evaluate the biofilm formation of bacteria isolated from marine sediments under in vitro conditions. For this, biofilm quantification assays were performed...

In coral reefs, competition between sessile benthic organisms for access to space and other resources is a determining factor in community structuring. Recent coral mortality has favored the development of algal turfs, which are now competing with corals, often displacing them,although slowly. To determine the frequency of interactions between cora...

In deep‐sea environments, plant remains of several origins are found, including branches, twigs, leaves, and wood pieces, among others. As most of the deep‐sea bottoms are oligotrophic and nutrient‐limited, plant remains provide an oasis of localized organic enrichment and a substrate for colonization. Sunken wood was suggested to play an important...

La Escollera, una laguna costera artificial, ubicada en el balneario turístico El Rodadero en Santa Marta. Se ha convertido en un laboratorio de investigación y está permitiendo realizar diferentes estudios en el ejercicio académico con el fin de propiciar la comprensión de estos ecosistemas. Hasta ahora no se había realizado ningún estudio sobre s...

Astrophorida is one of the most diverse (>820 species) and worldwide distributed orders of demosponges. These sponges are common colonizers of hard and soft-bottoms in a broad bathymetrical range. In hard-bottom habitats on the outer shelf and upper slope, astrophorids can dominate ecosystems in terms of abundance and biomass forming sponge grounds...

In tropical seas there are submerged hard bottoms that harbor corals but that are not coralline in origin. This is the case for the “Banco de las Ánimas” sector in the continental shelf of the Gulf of Salamanca, Colombian Caribbean. In its upper portion (14–16 m in depth), there are low mounds of sandstone blocks and slabs, conforming reefs, coloni...

Neopetrosia proxima (Porifera: Demospongiae: Haplosclerida) is described as a morphologically variable sponge common on shallow reefs of the Caribbean. However, the range of morphological and reproductive variation within putative N. proxima led us to hypothesize that such variability may be indicative of cryptic species rather than plasticity. Usi...

Coral reefs are commonly associated with oligotrophic, well-illuminated waters. In 2013, a healthy coral reef was discovered in one of the least expected places within the Colombian Caribbean: at the entrance of Cartagena Bay, a highly-polluted system that receives industrial and sewage waste, as well as high sediment and freshwater loads from an o...

Varadero and Barú coral species List of scleractinian and fire coral species in Varadero and Northern Barú Reefs. Data are the frequency of occurrence (average,%) or presence/absence (+∕ −, visual surveys).

Varadero and Barú sponge species List of sponge species comparing two reef zones in Varadero and Northern Barú Reefs. Data are frequency of occurrence (%, 30 ×2-m2 transects, n = 7 and 4 at Varadero and Barú, respectively), or presence (+, visual surveys).

Varadero and Barú fish species List of fish species observed at Varadero and Barú. Abundance values are mean (±S.D.) number of individuals per species observed in 30 ×2-m2 belt transects (n = 15 and 7 at Varadero and Barú, respectively). Species observed outside transects are indicated by an x.

Fish species richness variation at Barú and Varadero Reefs Variation in fish species richness as a function of number of visual censuses (sample-based rarefaction curves) for the fish censuses made at Barú and Varadero Reefs.

The macrolide (+)-discodermolide produced by the marine sponge Discodermia dissoluta shows promising antitumor, antimitotic, and immunosuppressive activity. However, the sustainable supply of any molecule requires much in situ and in vitro research to optimize and later obtain the molecule of interest. In this study, two culture systems—fixed and s...

Changes in coral-sponge interactions can alter reef accretion/erosion balance and are important to predict trends on current algal-dominated Caribbean reefs. Although sponge abundance is increasing on some coral reefs, we lack information on how shifts from corals to bioeroding sponges occur, and how environmental factors such as anomalous seawater...

Coral reefs supply millions of people with ecosystem goods and services, especially those living along tropical coastlines. Unfortunately, these ecosystems are disappearing at an alarming pace. In the Caribbean, the rate of coral loss is high (5.5 – 9.2% per year) and constant. In 2013, a healthy coral reef was discovered in one of the least expect...

Coral reefs supply millions of people with ecosystem goods and services, especially those living along tropical coastlines. Unfortunately, these ecosystems are disappearing at an alarming pace. In the Caribbean, the rate of coral loss is high (5.5 – 9.2% per year) and constant. In 2013, a healthy coral reef was discovered in one of the least expect...

Sponges (Porifera) are important constituents of littoral habitats in the Caribbean Sea. The knowledge of their biodiversity is fundamental to carry out ecological, managerial and utilitarian research. Their taxonomy is complex, but in the Caribbean in general, and in Colombia in particular, there are important advances. With this work, some sponge...

The increase in frequency and intensity of extreme oceanic events limits the capacity of recoveryof ecosystems, threatening their subsistence. Thus, in order to understand the relationship between coral healthand extreme environmental events, data on sea temperature, runoff and / or salinity, turbidity were analyzed in theIslas del Rosario in compa...

RESUMEN. El incremento en la frecuencia e intensidad de eventos oceánicos extremos limita la capacidad de recuperación de los ecosistemas, amenazando su subsistencia. Con el fin de entender la relación entre la estructura y salud arrecifal y los eventos extremos ambientales, se analizaron series de datos ambientales de las islas del Ro-sario (e.g.,...

Sponges (Porifera) are important constituents of littoral habitats in the Caribbean Sea. The knowledge of their biodiversity is fundamental to carry out ecological, managerial and utilitarian research. Their taxonomy is complex, but in the Caribbean in general, and in Colombia in particular, there are important advances. With this work, some sponge...

Although sponges are important components of benthic ecosystems of the Caribbean Sea, their diversity remained poorly investigated in the Lesser Antilles. By organizing a training course in Martinique, we wanted both to promote taxonomy and to provide a first inventory of the sponge diversity on this island. The course was like a naturalist expedit...

Waterproof plates presenting in situ pictures together with visual keys of identification of the most common sponges of the Caribbean Sea. (PDF)

On Caribbean reefs, the excavating sponge Cliona tenuis opportunistically colonized dead skeletons of the elkhorn coral Acropora palmata after its massive die-off in the 1980s. Further C. tenuis population increase occurred by colonization of other coral species, causing coral tissue death through undermining of live tissue and lateral growth. To f...

Identification of bioactive metabolite cell producers allow driving cell culture experiments for in vitro production, just as elucidation of the possible physiologic function of metabolites. The Caribbean marine sponge Discodermia dissoluta produces the polyketide (+)-discodermolide, a potent antitumoral that has reached clinic trials in humans. In...

Sponges are sessile organisms capable of colonizing diverse substrata. In the Caribbean, coral reefs have suffered a drastic decline, and branching corals of the genus Acropora have been widely decimated. On dead coral skeletons and around surviving tissue the settling of sessile organisms can be observed, sponges being common. In order to investig...

Several groups of sponges are able to excavate galleries and tunnels in calcareous substrata such as limestone rock, shells, calcareous algae and coral skeletons. Within the genus Cliona, some species share the common traits of being brown to olive-green in color, and harboring photosynthetic, unicellular dinoflagellates (zooxanthellae). These Clio...

The new discovery by Vicente et al. (2014) of specialized epizoic symbioses between sponges of the genera Plakortis and Xestospongia revealed the obligate interaction of two new Plakortis spp. associating with Xestospongia deweerdtae and a new Xestospongia sp. In this study we formally describe the two new Plakortis spp. as Plakortis deweerdtaephil...

Identification of bioactive metabolite cell producers allow driving cell culture experiments for in vitro production, just as elucidation of the possible physiologic function of metabolites. The Caribbean marine sponge Discodermia dissoluta produces the polyketide (+)-discodermolide, a potent antitumoral that has reached clinic trials in humans. In...

Above-normal meteorological and oceanographic conditions that generate damage on coastal ecosystems and associated human communities are called extreme oceanic events. Accurate data are needed to predict their occurrence and to understand their effects. We analyzed available data from four localities in the Colombian Caribbean to study the effect o...

http://www.invemar.org.co/documents/10182/14479/biodiversidad-del-mar-de-los-siete-colores-web.pdf

Although there is a long history of taxonomic investigation in Caribbean sponges, there are still many undescribed species. Furthermore, field observations and corroborating morphological analyses are revealing that what was believed to be sin-gle, somewhat variable species, may consist of two or more species, often easier to distinguish once well...

Day-night and between-day variation in surficial zooplankton composition and its relationship to environmental parameters were analyzed in the Santa Marta Bay, Colombian Caribbean, by Principal Components Analysis. Sampling was carried out every four hours in three different days between August and October 1989. The greatest variation in abundance...

Temperaturas del agua de mar por encima del promedio durante 2005 en el Archipiélago de las Islas del Rosario (Caribe Colombiano) causaron un blanqueamiento coralino masivo en aguas someras (hasta 2-3 m de profundidad). Para confirmar resultados previos en los que el estrés inducido por calentamiento del agua en los corales puede acelerar la veloci...

Meiofaunal assemblages colonizing authigenic carbonates at Costa Rica cold seeps.

Slattery & Lesser (2015; Mar Ecol Prog Ser 527:275–279) offer a Comment on our review of the literature for evidence of bottom-up control of sponge communities on Caribbean reefs. We briefly address the criticisms presented in the Comment and reiterate the lack of evidence for food limitation, including inter-oceanic comparisons of Caribbean reefs...

The diversity and biomass of sponges on Caribbean reefs exceeds that of all other benthic organisms. Wilkinson & Cheshire (1990; Mar Ecol Prog Ser 67:285-294) summarized evidence that sponge communities on Caribbean reefs were different from those on the Great Barrier Reef, Australia, reflecting food limitation of the latter, but not of the former....

While sea surface temperature has been considered the environmental variable with the greatest impact on coral bleaching, other variables also modify the susceptibility of reefs and generate spatial differences of this phenomenon. In four locations in the Colombian Caribbean, sea surface temperature, chlorophyll, turbidity, flow of rivers, winds an...

Resumen: Aunque la temperatura superficial del mar se ha considerado como la variable ambiental con mayor incidencia en el blanqueamiento coralino, se ha encontrado que otras variables también intervienen en este fenómeno, modificando la susceptibilidad de los arrecifes y generando diferencias espaciales. En el Caribe colombiano se estudiaron las v...

Three new cases of sponge symbiosis between species of Plakortis and Xestospongia were found in reef caves and mesophotic reef habitats of the Caribbean. Plakortis sp. 1 from the Bahamas associates exclusively with Xestospongia deweerdtae which was originally described living freely on the deep fore-reef and caves of Jamaica. In addition, we found...

Thinly encrusting sponges are diverse and ecologically important, but their taxonomy is challenging. In the Greater Caribbean, the recognition of species of Clathria (Thalysias), most of which are encrusting, is still problematic. Here we describe and clarify the taxonomy of eight species, three new to science, from material collected mostly in Col...

The genus Agelas comprises a group of tropical and subtropical reef sponges that contains large, long-lived, often brightly colored and conspicuous species, distributed throughout the tropical western Atlantic, temperate northern Atlantic (Mediterranean Sea), and western and central Indo-Pacific Realms. Among tropical sponge genera, Agelas is one w...

Exploration of continental shelves may produce unexpected faunal records. In shelf waters of La Guajira peninsula, Colombia, in the northern tip of South America, southern Caribbean Sea, we found a new species of Rhaphidhistia (Demospongiae, Hadromerida, Trachycladidae) a genus previously thought to be restricted to the Indo-Pacific Ocean. Rhaphidh...

Background / Purpose: The Joint Regime Area (JRA) is an oceanic complex mostly conformed by deep seabed shared by Colombia and Jamaica in the Caribbean Sea. The marine environment and benthic communities of the JRA have until now received little attention. This is the first study to investigate the sponge diversity of this area, based on trawls c...

Methodological desing for the study of meio-epifaunal communities in Costa Rica.

The North-West Gulf of Urabá, Colombia, harbors the southernmost Caribbean reefs, exposed to high turbulence and fluctuating turbidity and salinity. An annotated systematic check-list of sponges from this area is presented. A total of 77 demosponge species (class Demospongiae), 3 homoscleromorph species (class Homoscleromorpha) and 1 calcareous spe...

Direct field observations often reveal distinct morphotypes within sponge species that had been described on the basis of preserved material from different locations. The genus Axinyssa von Lendefeld, 1897 was revised for the Caribbean by Diaz et al. (1993), defining a single species, Axinyssa ambrosia (de Laubenfels, 1936), with several junior syn...

Biotechnological research on marine organisms, such as ex situ or in situ aquaculture and in vitro cell culture, is being conducted to produce bioactive metabolites for biomedical and industrial uses. The Caribbean marine sponge Discodermia dissoluta is the source of (+)-discodermolide, a potent antitumoural polyketide that has reached clinical tri...

The parrotfish Sparisoma viride often grazes live coral from edges undermined by the Caribbean encrusting and excavating sponge Cliona tenuis. To test whether parrotfish biting action has an effect on the dynamics of the sponge–coral interaction, we manipulated access of parrotfishes to the sponge–coral border in two species of massive corals. When...

The marine sponge Discodermia dissoluta is a source of the polyketide discodermolide, a potent antitumoral agent that has reached clinical trials in humans. In Santa Marta, where this species occurs at shallower depths than in other Caribbean areas, for the first time it was possible to study by SCUBA its ecological characteristics, distribution an...

ABSTRACT Natural history of the sponge Discodermia dissoluta (Porifera: Demospongiae: Lithistida) in Santa Marta, Colombian Caribbean. The marine sponge Discodermia dissoluta is a source of the polyketide discodermolide, a potent antitumoral agent that has reached clinical trials in humans. In Santa Marta, where this species occurs at shallower dep...

The Caribbean sponge Cliona delitrix is among the strongest reef space competitors; it is able to overpower entire coral heads by undermining coral polyps. It has become abundant in reefs exposed to organic pollution, such as San Andre´s Island, Colombia, SW Caribbean. Forty-four sponge-colonized coral colonies were followed-up for 13 months to est...

Sanchez Vega René, Maribeb Castro-González & Sven Zea At the Ciénaga Grande de Santa Marta (CGSM) in the Colombian Caribbean, has been registered high primary production (PP) values in comparison to other aquatic ecosystems of the world. As N appears to be the limiting element to PP, owing to its relatively low concentration with respect to P, nut...

The Colombian Caribbean Sea coastal presents both continental and oceanic coral reef ecosystems. ecosystems. Based on quantitative sampling using video transects and multivariate analyses we Based on quantitative sampling Transects and video using multivariate analysis we found that there are small (hundreds of meters to few kilometers) and large s...

The fatty acid composition of whole phospholipids from marine sponges collected from the Colombian Caribbean Sea was determined as part of our studies on the order Halichondrida: Halichondria magniconulosa, Halichondria lutea, Petromica ciocalyptoides, Axinyssa ambrosia, Didiscus oxeata and Dragmaxia undata. Structure elucidation was accomplished b...

The sponge Discodermia dissoluta is the source of the potent antimitotic compound (+)-discodermolide. The relatively abundant and shallow populations of this sponge in Santa Marta, Colombia, allow for studies to evaluate the natural and biotechnological supply options of (+)-discodermolide. In this work, an RP-HPLC-UV methodology for the quantifica...

Long-term monitoring data provide a basis to recognize changes in coral reef communities and to implement appropriate management strategies. Unfortunately, coral reef dynamics have been poorly documented at any temporal scale in the Southern Caribbean. Through the "National Monitoring System of Coral Reefs in Colombia" (Spanish acronym: SIMAC), we...

Surfaces submerged in the sea are densely colonized by bacteria, and inter-specific interactions such as growth inhibition are important determinants of the development of bacterial communities, as well as of later phases of macrofouling. To determine the potential interactions among biofilm bacteria from sponges we carried out in vitro growth inhi...

Surfaces submerged in the sea are densely colonized by bacteria, and inter-specific interactions such as growth inhibition are important determinants of the development of bacterial communities, as well as of later phases of macrofouling. To determine the potential interactions among biofilm bacteria from sponges we carried out in vitro growth inhi...

The Caribbean encrusting and excavating sponge Cliona tenuis successfully competes for space with reef corals by undermining, killing, and displacing live coral tissue at rates of up to 20 cm per year. The crude extract from this sponge, along with the more polar partitions, kills coral tissue and lowers the photosynthetic potential of coral zooxan...

During the exploration of the soft calcareous bottoms of the continental shelf of La Guajira Department, 47 different species of sponges were identified in the classes Demospongiae and Calcarea. From bottom trawling carried out throughout the continental shelf on the bathymetric fringes of 10 and 50 m, it was found that the number of species is lar...

Phylogenetic relationships of symbiotic dinoflagellate lineages, distributed in all tropical and subtropical seas, suggest strategies for long distance dispersal but at the same time strong host specialization. Zooxanthellae (Symbiodinium: Dinophyta), which are associated to diverse shallow-water cnidarians, also engage in symbioses with some spong...