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Clionaids are excavating sponges, which live in and grow into calcareous substrates. We studied the sexual reproductive cycles of two clionaid sponges coexisting in a Mediterranean coastal basin (Porto Cesareo, Italy), Cliona viridis and Cliona celata, by analyzing monthly tissue samples of ten specimens of each species collected over a 2-year period. From May to June of the second study year, supplementary samples were taken weekly. Up to 90% of the specimens of C. viridis and 70% of those of C. celata sampled were reproductive during the study. In both species, but particularly in C. viridis, reproductive investment, measured as the percentage of sponge tissue occupied by gametes, was high. Oocytes were present almost year-round in both species, except for a 1–4-month period after zygote release. In contrast, spermatogenesis occurred most frequently in May in both species, when (May–June) oocytes reached their greatest diameters. Cliona viridis and C. celata are hermaphrodites, with oocytes and spermatic cysts coexisting in 10% of the studied individuals in the first year of the study, and in 30% during the second. No developing embryos or larvae were incubated in the sponge tissues, and fertilization was not observed. Temperature may play a role in triggering some important phases of the reproduction of these Cliona, such as oocyte maturation and spermatogenesis, which occurred when water temperature increased from 17°C to 25°C between May and June.

Aim Variation in the structure of shallow subtidal invertebrate assemblages was examined over three spatial scales; within reef, between reef and between continents. We sought to provide a context from which to examine and interpret ecological processes between continents. In addition, we predicted that variation in pattern would increase as the scale of examination increased. Location Reefs near Wollongong and within Jervis Bay in south-eastern Australia and Mediterranean reefs on the Costa Brava (Catalonia), north-eastern Spain. Methods We compared assemblages on vertical rock walls of two heights – short ( 3 m) in two temperate regions over the same depth range. Specifically we examined the diversity and cover of invertebrates, the cover and biomass of foliose and crustose algae, the size of invertebrate colonies and the biomass of urchins on short and tall walls (n = 3) at each of two locations in each country. Results Foliose algae dominated rock walls in Spain and although invertebrate cover was high, colonies were generally very small. Two urchin species were commonly encountered on rock walls in Spain, Arbacia lixula and Paracentrotus lividus; their biomass was relatively low and did not differ significantly between short and tall walls. These findings contrasted strongly with south-eastern Australia, where foliose algae were almost completely absent. A single urchin species, Centrostephanus rodgersii occurred with extremely high biomass on short walls, which were dominated by grazer-resistant crustose calcareous algae. In contrast, the biomass of this urchin was low on tall walls, which were dominated by invertebrates, usually exceeding 95% in cover. Invertebrate colonies were significantly larger on both short and tall walls in south-eastern Australia relative to the Mediterranean. Findings within a country were consistent between the replicate rock walls and between locations. In contrast to our prediction, however, there was significant variation among walls within a location, but not among locations within a continent. Temporal variation in the structure of these assemblages was not examined, but appears limited. Main conclusions We conclude that submarine topography, i.e. the presence of short or tall rock walls, as a function of rock type and structure, has a marked impact on community structure in south-eastern Australia, but made little difference to the structure of the assemblage in Mediterranean Spain. The differences in structure we observed between walls of different heights in Australia were correlated with differences in the biomass of urchins and they appear to be major determinants of assemblage structure. Interactions among species are often reported from disparate parts of the globe with little or no reference to the structure of the assemblage of which they are a part; we contend that this will hinder interpretation. Our data are consistent with the organisms in these two regions experiencing distinct selection pressures; for example high levels of urchin grazing activity in south-eastern Australia, and shading and whiplash associated with an algal canopy in the Mediterranean. It may not be appropriate to contrast processes operating at very large (intercontinental) scales unless context can be established with a clear understanding of ecological pattern. Objectivos En el presente trabajo hemos examinado la variacion en estructura de comunidades de invertebrados de aguas someras a tres escalas espaciales: dentro de arrecifes rocosos, entre arrecifes y entre continentes. Nuestro objetivo era proveer un contexto para examinar y interpretar procesos ecologicos entre continentes. Ademas, realizamos la prediccion de que el modelo de variacion aumentaria conforme aumentaba la escala de observacion. Localidad Arrecifes rocosos cerca de Wollongong y en Jarvis Bay en la zona sudeste de Australia y arrecifes rocosos mediterraneos en la Costa Brava (Cataluna), en el nordeste de Espana. Metodos Comparamos comunidades en paredes rocosas verticales de dos alturas – bajas ( 3 m) en dos regiones templadas y dentro del mismo rango de profundidades. Especificamente, examinamos la diversidad y el recubrimiento de invertebrados, el recubrimiento y la biomasa de algas foliosas e incrustantes, la medida de las colonias de invertebrados y la biomasa de erizos en paredes bajas y altas (n = 3) en dos localidades de cada pais. Resultados Las algas foliosas dominaban las paredes rocosas en Espana y, aunque el recubrimiento de invertebrados era alto, las colonias eran generalmente muy pequenas. Dos especies de erizos eran comunes en las paredes rocosas en Espana: Arbacia lixula y Paracentrotus lividus. Su biomasa total era relativamente pequena y no mostraba diferencias significativas entre paredes bajas y altas. Estos resultados contrastan con los hallados en el sudeste de Australia, donde las algas foliosas eran practicamente ausentes. Una unica especie de erizo, Centrostephanus rodgersii, se encontraba en las paredes bajas, donde presentaba elevadas biomasas. Estas paredes estaban dominadas por algas incrustantes y carbonatadas resistentes al ramoneo por erizos. En cambio, la biomasa de este erizo era baja en paredes altas, que estaban dominadas por invertebrados, con recubrimientos normalmente por encima del 95%. Las colonias de invertebrados eran significativamente mas grandes tanto en las paredes altas como bajas en el sudeste de Australia en comparacion con el Mediterraneo. Los resultados dentro de cada pais eran consistentes entre las replicas de paredes estudiadas y entre localidades. Contrariamente a nuestra prediccion, sin embargo, habia una variacion significativa entre paredes dentro de una localidad pero no entre localidades dentro de un continente. La variacion temporal en estructura en estas comunidades no fue estudiada, pero parece ser limitada. Conclusiones Principales Concluimos que la topografia submarina, esto es, la presencia de paredes bajas o altas en funcion del tipo de roca y estructura, tiene un efecto importante en la estructura de las comunidades en el sudeste de Australia. Este factor, sin embargo, tiene un efecto muy limitado en el Mediterraneo espanol. Las diferencias en estructura observadas entre paredes de diferentes alturas en Australia se correlacionan con diferencias en la biomasa de erizos, los cuales parecen ser determinantes en la estructura de las comunidades. Frecuentemente se estudian interacciones entre especies en zonas alejadas del globo con escasa o nula referencia a la estructura de la comunidad de la que forman parte. En nuestra opinion este hecho impide una correcta interpretacion. Nuestros datos son consistentes con la idea de que los organismos en las dos regiones estudiadas experimentan diversas presiones selectivas, por ejemplo, niveles altos de ramoneo por erizos en el sudeste de Australia, y oscurecimiento y disturbancia mecanica asociadas a la cobertura de algas en el Mediterraneo. No parece apropiado comparar procesos que operan a escalas muy amplias (intercontinentales) sin establecer antes un contexto con una comprension clara de los parametros ecologicos.

Microtox® assay was used to assess the natural toxicity of two sponges, Dysidea avara and Ircinia variabilis. The activity of crude extracts and major metabolites were compared. Methanol extract of D. avara was more toxic than that of acetone and was as toxic as pure avarol, thus suggesting that the toxicity of the sponge was mainly due to this metabolite. We also quantified palinurin, the major metabolite of I. variabilis, in specimens from several habitats. With the same methanol extracts used for palinurin quantification, we ran the Microtox® assay and found a positive significant regression between toxicity and concentration of this metabolite. Pure palinurin was tested at the same concentration present in the extract, and the toxicity recorded was higher than that of the methanol extract. As with avarol from D. avara, palinurin is the main secondary metabolite that confers toxicity to I. variabilis. The results confirm that the standardized Microtox® assay is an accurate and reproducible tool for assessing the toxicity of crude extracts and pure metabolites of marine organisms. These results also suggest that methanol is more suitable than acetone for the detection of species toxicity by Microtox® The method is faster and easier to perform than chemical quantification even when the sponge chemistry is known, and is appropriate for studies on variation in natural toxicity over a range of environmental conditions.

Four copepod species of the genus Asterocheres (A. echinicola, A. latus, A. suberitis and A. complexus) are recorded for the first time as associated with Mediterranean sponges of the classes Calcarea and Demospongiae (orders Dictyoceratida, Dendroceratida, and Poecilosclerida). Individuals of A. suberitis are described for the first time as inhabiting sponges other than Suberites domuncula. The copepods seemed to use their trunk to suck the material (cuticles or excreted cells) produced at the sponge periphery (ectosome), which indicates that their feeding habits are similar to those observed in species of the same genus that feed on exfoliated tissues of echinoderms. In the laboratory, copepods fed on young sponges (rhagons) of the species Crambe crambe, Cacospongia mollior, and Dysidea avara without reducing the rhagon biomass. In contrast, rhagons of the species Haliclona sp., Hymedesmia spp., and Phorbas tenacior were consumed and their biomass reduced. This may be because the latter group does not produce external proteinaceous material. Copepod offspring were continuously released (∼6 nauplii every 48 h) and the larval stages were capable of limited swimming. We found significantly more copepods over the surface of the sponges than inside them. Copepod abundance was positively correlated with the sponge surface area while not with the sponge biomass. These results indicate that the copepods live preferentially over the sponge surface and that their abundance is surface-area dependent. The behavioral traits described here indicate that the interactions between asterocherid species and sponges are worthy of future study.

We performed an intensive year-round sampling with the aim of studying the abundance of sponge larvae in four Mediterranean benthic communities: photophilic algae, sciaphilous algae, semi-obscure (i.e. low light-intensity) caves and sandy bottoms. We record here for the first time, a larval bloom of Cliona viridis (Schmidt 1862), the most common excavating sponge in the Mediterranean, which took place simultaneously in several rocky communities of the Blanes sub-littoral (NE Spain), and discuss the role of restricted larval dispersal in the distribution of adult sponges. In the communities studied, C. viridis larvae bloomed synchronously once, in June. Spawning and consequent embryo development presumably occurred in May, when water temperature was 16 °C. The free larva is a small, evenly ciliated, weakly swimming parenchymella with low dispersal capabilities. The number of larvae m−3 and sponge abundance (as percent cover and biomass) were significantly higher in the community of sciaphilous algae than in the other communities studied. Because of limited larval dispersal, larval and adult abundance in the communities were positively correlated. Larvae developed into juvenile sponges 10 to 15 d after settlement. Settlers displayed distinctive features: a peripheral cuticle, vacuolar etching-like cells at the sponge base, absence of oscular chimneys, and the presence of zooxanthellae, which were presumably transmitted during oocyte maturation.

Knowledge of the functioning, health state, and capacity for recovery of marine benthic organisms and assemblages has become essential to adequately manage and preserve marine biodiversity. Molecular tools have allowed an entirely new way to tackle old and new questions in conservation biology and ecology, and sponge science is following this lead. In this review, we discuss the biological and ecological studies of sponges that have used molecular markers during the past 20 years and present an outlook for expected trends in the molecular ecology of sponges in the near future. We go from (1) the interface between inter- and intraspecies studies, to (2) phylogeography and population level analyses, (3) intra-population features such as clonality and chimerism, and (4) environmentally modulated gene expression. A range of molecular markers has been assayed with contrasting success to reveal cryptic species and to assess the genetic diversity and connectivity of sponge populations, as well as their capacity to respond to environmental changes. We discuss the pros and cons of the molecular gene partitions used to date and the prospects of a plentiful supply of new markers for sponge ecological studies in the near future, in light of recently available molecular technologies. We predict that molecular ecology studies of sponges will move from genetics (the use of one or some genes) to genomics (extensive genome or transcriptome sequencing) in the forthcoming years and that sponge ecologists will take advantage of this research trend to answer ecological and biological questions that would have been impossible to address a few years ago.

Several samples of Raspaciona aculeata collected from the same area (Blanes) displayed completely different metabolite patterns characterized either by already known triterpenes, raspacionins, or by blanesin (2). Blanesin is a new ent-labdane furanoditerpenoid with an α-hydroxyketone in the ring A. Structure and absolute stereochemistry were established by spectroscopic and chemical methods.

Eight new minor triterpenoids have been characterized from a lipid-soluble extract of Raspaciona aculeata. All are based on the same carbon skeleton as raspacionin [1]. The full assignment of all 1 H- and 13 C-nmr resonances has led to the rationalization of the effects of certain substituents on the chemical shifts of atoms in the perhydrobenzoxepine system

This is the first report of egg release by the oviparous excavating sponge Cliona viridis. Adult specimens of excavating (α) and massive (β) sponge forms for the presence of oocytes were monitored from 11 May to 12 July 2000, in a shallow-rocky coast of the north-west Mediterranean. The immediate environment around the sponge was sampled for the presence of eggs. Spawning occurred synchronously in the study area at temperatures above 19°C. Oocytes were released in clusters enclosed in adhesive maternal tissue. They contained symbiotic zooxanthellae. Free, adhesive egg-masses drifted in the water or adhered to erect algae in the vicinity of the sponge. Morula stages and larval release are described.

4 páginas., This paper reports the chemical study of a sample of Fasciospongia sp. collected along the Atlantic Portuguese coast. Three new isomeric furanosesquiterpenes, isomicrocionin-3 (1), (−)-microcionin-1 (2), and (−)-isomicrocionin-1 (3), were isolated along with the known (−)-ent-pallescensin A (4) and (−)-pallescensin-1 (5) from the ethyl acetate-soluble portion of the methanolic extract. The structures of the new compounds were elucidated by extensive spectroscopic studies. (−)-Microcionin-1 (2) tested positive against several Gram-negative bacteria.

Geodiidae Gray (Demospongiae, Astrophorida) includes astrophorid sponges with sterrasters as the main cortical microsclere and various forms of triaenes among the megascleres. Other microscleres present are euasters and microrhabds. Sponges are generally massive or thickly encrusting and often develop into globular forms. The inhalant or exhalant orifices (or both) may be organized in a sieve. The skeletal arrangement is radiate at the periphery and confused in the inner region of the skeleton. These sponges are usually cream, gray or white in color inside, and gray, brown to black outside, often dependant on their exposure to light. They inhabit bathyal, soft bottoms and, less often, are found in caves and overhangs of the sublittoral zone. The family contains twelve nominal genera of which six are valid: Erylus, Caminus, Pachymatisma, Geodia, Isops, and Sidonops, with species distributed worldwide.

Evidence is presented for an annual cycle of toxin production in the encrusting sponge Crambe crambe. Both sponge toxicity and the slope of the regression line between toxicity and extract concentration (which is taken to represent qualitative properties of the toxins) changed following a seasonal pattern, with maxima in summer and autumn. Within-colony variation was also detected. On average, the values of toxicity were higher at the periphery than in the centre. The reverse was true if the variable considered was the slope of the toxicity function. There was decoupling during particular seasons in the evolution of these variables in the central and the peripheral parts of the sponges, with a retardation of the maxima in the latter. It is suggested that the cycles are driven by internal, physiological factors (best represented in the central part of the sponges), although they can be modulated to a considerable extent by local environmental pressures, such as competition with neighbours (best seen in the evolution of the toxicity in the peripheral part of the sponge). The results are interpreted from the point of view of their biological and ecological implications, inducible defences, and optimal defence theory.

16 páginas, 6 tablas, 8 figuras., Sponges are considered poor invaders, and no genetic studies on introduced sponges have been performed up to now. Paraleucilla magna is the first calcareous sponge introduced to the Mediterranean and Northeastern Atlantic. The study aimed at investigating the genetic makeup and connectivity of the introduced populations of P. magna and at exploring signs of local phenotypic adaptation, to gain insight on the species invasive potential. Ten populations along the species introduction range (Brazil, Açores, Madeira, and continental Europe) were genetically characterized by using nine microsatellite markers. Most populations were genetically structured as suggested by significant Dst and Fst values, significant differences among populations (AMOVA) and the presence of private alleles. The analyzed populations belonged to three genetically homogeneous groups (K) according to the Bayesian algorithm (structure software) and the UPGMA dendrogram. Genetic diversity within populations was higher than expected. Recurrent introductions of non-randomly selected individuals from the native sources may have contributed to the heterozygote deficit found in all populations by forming pedigree structures with mating among relatives. Moreover, the species biological cycle was monitored in a population established on native Mediterranean assemblages (41°40′27″N, 2°47′25″E) and compared with the species cycle in other habitats. Contrasting life spans, growth habits, and reproduction cycles, depending on the habitat conditions, were recorded. To summarize, high genetic diversity, phenotypic local adaptation, and high reproduction rates altogether allow predicting the fast proliferation of P. magna in newly colonized regions and point to its strong invasive potential., This study has been partially funded by MARSYMBIOMICS project ref. CTM2013-43287-P (Spanish Ministry of Economy and Competitiveness (MINECO)—FECYT agency, and Consolidate Group Award 2009-SGR655 (Generalitat of Catalonian) to MJU. MG has benefited from a FPU fellowship from the Spanish MINECO and JF from a Marie Curie (EU) fellowship, associated, respectively, with the BENTHOMICS and BIOCAPITAL projects to MJU.