Nodipecten Nodosus Research Articles

Potentially toxic filamentous fungi associated to the economically important Nodipecten nodosus (Linnaeus, 1758) scallop farmed in southeastern Rio de Janeiro, Brazil

Numerous countries have been confronted with infectious diseases in mariculture activities, including fungi infections, although reports in scallops are scarce. Thus, this study aimed to investigate the occurrence of filamentous fungi in Nodipecten nodosus specimens from three marine farms in Southeastern Brazil. Eight fungi genera were observed in the branchial arches, intestine and muscle tissue of the scallop specimens. These include potentially toxin-producing species, such as Aspergillus, Penicillium and Fusarium. Their presence may lead to potential public health concerns, since all sampling sites showed the presence of fungi in all scallop organs, with special concern regarding edible muscle tissue. A significant number of species was observed at one of the study areas, which could indicate a previously unknown source of contamination, since increases in fungi species richness in polluted coastal waters have been reported. This is also, to the best of our knowledge, the first report of Pestalotiopsis in shellfish.

Exposure to phenanthrene and depuration: Changes on gene transcription, enzymatic activity and lipid peroxidation in gill of scallops Nodipecten nodosus

Understanding the mechanism of phenanthrene (PHE) biotransformation and related cellular responses in bivalves can be an important tool to elucidate the risks of polycyclic aromatic hydrocarbons (PAHs) to aquatic organisms. In the present study it was analyzed the transcriptional levels of 13 biotransformation genes related to cytochrome P450 (CYP), glutathione S-transferase (GST), sulfotransferase (SULT), flavin-containing monooxygenase and fatty acid-binding proteins by qPCR in gill of scallops Nodipecten nodosus exposed for 24 or 96h to 50 or 200μgL−1 PHE (equivalent to 0.28 and 1.12μM, respectively), followed by depuration in clean water for 96h (DEP). Likewise, it was quantified the activity of catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), glutathione reductase (GR), glucose 6-phosphate dehydrogenase (G6PDH), GST and levels of lipid peroxidation. Increased transcriptional levels of CYP2UI-like, CYP2D20-like, CYP3A11-like, GSTomega-like, SULT1B1-like genes were detected in organisms exposed to PHE for 24 or 96h. In parallel, GR and GPX activities increased after 96h exposure to 200μgL−1 PHE and G6PDH activity increased after 24h exposure to 50μgL−1 PHE. This enhancement of antioxidant and phase I and II biotransformation systems may be related to the 2.7 and 12.5 fold increases in PHE bioaccumulation after 96h exposure to 50 and 200μgL−1 PHE, respectively. Interestingly, DEP caused reestablishment of GPX and GR activity, as well as to the transcript levels of all upregulated biotransformation genes (except for SULT1B1-like). Bioaccumulated PHE levels decreased 2.5–2.9 fold after depuration, although some biochemical and molecular modifications were still present. Lipid peroxidation levels remained lower in animals exposed to 200μgL−1 PHE for 24h and DEP. These data indicate that N. nodosus is able to induce an antioxidant and biotransformation-related response to PHE exposure, counteracting its toxicity, and DEP can be an effective protocol for bivalve depuration after PHE exposure.

Estimation of growth parameters in a wild population of lion-paw scallop (Nodipecten subnodosus ) in Bahia de Los Angeles, Baja California, Mexico

The lion-paw scallop Nodipecten subnodosus is a commercially important resource in the northwest of Mexico; however few studies evaluate its growth. Length of shell was used to estimate individual growth parameters of the lion-paw scallop from a wild population. Monthly samplings were performed from January to December 2006 in Bahia de Los Angeles on the western coast of the Gulf of California, Mexico. Morphometric relationships between total length, height, total weight, and mass weight were estimated. The number of cohorts was determined monthly using the multinomial technique based on a likelihood function. The cohort that was best represented over time was used to fit the stationary growth model of von Bertalanffy. The results indicated that this species presents negative allometric growth and showed high correlation among different morphometric measures (R2 > 0.88). Length frequency distributions showed two cohorts in each sample, except from August to November when there were up to three cohorts, with greater variance in those of intermediate sizes. The growth parameters were: L? = 19.06 cm, k = 0.47 year-1, t0 = -0.19 years, C = 0.38, ts = 0.37. Due to fluctuations in the growth of the species, assessments should be performed based on age-structured models to support fishery management measures for this species.

A Status Assessment of Perkinsiosis, Bonamiosis, and Mateiliosis in Commercial Marine Bivalves from Southern Brazil

ABSTRACT The protozoans Perkinsus marinus, Perkinsus olseni, Bonamia ostreae, Bonamia exitiosa, and Marteilia refringens are responsible for some of the most detrimental diseases in the production of cultivated shellfish worldwide and are classified as notifiable diseases by the World Organization for Animal Health (OIE). This study examined the general health status of wild and cultured bivalves from southern Brazil and included diagnostic tests for the presence of Perkinsus sp., Bonamia sp., andMarteilia sp. Cultured bivalves included the mangrove oyster Crassostrea gasar (syn. Crassostrea brasiliana), the brown mussel Perna perna, the lion's paw scallop Nodipecten nodosus, andwing pearl oyster Pteria hirundo. Themangrove oyster Crassostrea rhizophorae and the carib pointed venus clam Anomalocardia brasiliana (syn. Anomalocardia flexuosa) were collected from wild populations. A variety of parasitic or commensal organisms were detected by histology including Ancistrocoma-like and Spenophrya-like organism...

First records of polyclads (Platyhelminthes, Polycladida) associated with Nodipecten nodosus (Linnaeus 1758) aquaculture

Free-living marine Platyhelminthes of the order Polycladida are known to interact with molluscs, especially bivalves. The impact and damage of polyclads that feed on farmed oysters can be so significant that they are known as oyster leeches. The present contribution identifies three species of polyclads associated with scallop aquaculture at Ilha Grande, southeastern Brazil: one cotylean, Lurymare matarazzoi, and two acotyleans, Imogine tica and Imogine refertus. This is the first time these species are illustrated with photographs of live specimens and histological sections after their original description. This is also the first record of an association of polyclads with a pectinid mollusc. The ecological role of polyclads is still little known, and experiments are lacking. However, it shows that native flatworm species are interacting with Nodipecten nodosus in experimental aquaculture, feeding either on the molluscs or on the associated fauna.

Metal bioaccumulation in consumed marine bivalves in Southeast Brazilian coast

This work aimed to investigate metal bioaccumulation by mussels (Perna perna) and Lion's Scallop (Nodipecten nodosus) farmed in tropical bays, in order to estimate spatial and temporal variation in the exposure to these elements, as well as human health risk. The concentration of each measured element was considered for this evaluation, using maximum residue level (MRL) in foods established by the Brazilian (ANVISA), American (USFDA) and European Communities (EC) legislations. Values for estimated daily ingestion (EDI) were determined for metals intake through mussel and scallop consumption. These estimates were compared with the reference value of (PTDI) proposed by World Health Organization (WHO). Trace elements concentration was measured on ninety mussels P. perna (tissue) and ninety Lion's Scallop N. nodosus (muscle and gonad) reared in four different tropical areas of the Southeast Brazilian coast, between 2009 and 2010. Zinc (Zn), Iron (Fe), Copper (Cu), Manganese (Mn), Chrome (Cr), Nickel (Ni), Cadmium (Cd) and Lead (Pb) concentrations were measured by flame atomic absorption spectrometry after acid mineralization. Cd and Mn were more efficiently bioaccumulated by scallops than mussels and the opposite was found for Fe, Cu and Ni. Guanabara Bay and Sepetiba Bay were considered the most impacted between ecosystems studied. Higher Cd values in Arraial do Cabo in the other sites studied were associated with upwelling that occurs in the region. Consumption of both species cannot be considered safe, because the Cu and Cr concentrations, in accordance with the limits established by the Brazilian Agency (ANVISA). On the other hand, any EDI value exceeded the corresponding value of the PTDI, proposed by World Health Organization (WHO).

Inferring muscular ground patterns in Bivalvia: Myogenesis in the scallop Nodipecten nodosus.

BackgroundMyogenesis is currently investigated in a number of invertebrate taxa using combined techniques, including fluorescence labeling, confocal microscopy, and 3D imaging, in order to understand anatomical and functional issues and to contribute to evolutionary questions. Although developmental studies on the gross morphology of bivalves have been extensively pursued, organogenesis including muscle development has been scarcely investigated so far.ResultsThe present study describes in detail myogenesis in the scallop Nodipecten nodosus (Linnaeus, 1758) during larval and postmetamorphic stages by means of light, electron, and confocal microscopy. The veliger muscle system consists of an anterior adductor muscle, as well as four branched pairs of striated velum retractors and two pairs of striated ventral larval retractors. The pediveliger stage exhibits a considerably elaborated musculature comprising the velum retractors, the future adult foot retractor, mantle (pallial) muscles, and the anterior and posterior adductors, both composed of smooth and striated portions. During metamorphosis, all larval retractors together with the anterior adductor degenerate, resulting in the adult monomyarian condition, whereby the posterior adductor retains both myofiber types. Three muscle groups, i.e., the posterior adductor, foot retractor, and pallial muscles, have their origin prior to metamorphosis and are subsequently remodeled.ConclusionsOur data suggest a dimyarian condition (i.e., the presence of an anterior and a posterior adductor in the adult) as the basal condition for pectinids. Comparative analysis of myogenesis across Bivalvia strongly argues for ontogenetic and evolutionary independence of larval retractors from the adult musculature, as well as a complex set of larval retractor muscles in the last common bivalve ancestor.Electronic supplementary materialThe online version of this article (doi:10.1186/s12983-015-0125-x) contains supplementary material, which is available to authorized users.

Anatomy of the pallial tentacular organs of the scallop Nodipecten nodosus (Linnaeus, 1758) (Bivalvia: Pectinidae)

Tentacular organs comprise a variety of body projections that have specialized functions in several invertebrate phyla. In bivalve mollusks, tentacles of the mantle margin serve sensorial and secretory functions involved in predator detection and interactions with the surrounding environment. However, their morphological diversity, detailed anatomy, and functional roles have only been scarcely investigated. Bivalves from the family Pectinidae are of particular interest in this context given the diversity of pallial tentacles, including distinct tentacle types arising on different mantle folds, and even eye-bearing tentacles. Combining several microscopy techniques, the present study investigates the anatomy of tentacular organs in postmetamorphic stages (juveniles and adults) of the scallop Nodipecten nodosus (Linnaeus, 1758). Scallop tentacles are formed shortly after metamorphosis, and except for pigmentation, they grow with no major morphological modifications. Tentacular organs of N. nodosus comprise eye-bearing and short and long tentacles from the middle mantle fold as well as velar tentacles from the inner fold. Although all tentacle types share a common basic structure (i.e., ciliated epithelium, peripheral muscle bundles, and a central nerve), they exhibit marked differences in ciliary distribution, epithelial secretory activity, and type of muscle fibers. Cilia distribution at the distal tip of sensory papillae represents a unique condition for the long tentacles from the middle mantle fold, and mucous secretion is restricted to the middle fold tentacles (except for eyestalks). Strikingly, velar tentacles and middle fold tentacles exhibit striated and non-striated myofibers, respectively. The data presented herein are discussed in light of the functional anatomy of the bivalve mantle margin.

Mantle margin morphogenesis in Nodipecten nodosus (Mollusca: Bivalvia): new insights into the development and the roles of bivalve pallial folds.

BackgroundDespite extensive knowledge on bivalve anatomy and development, the formation and differentiation of the mantle margin and its associated organs remain largely unclear. Bivalves from the family Pectinidae (scallops) are particularly promising to cast some light on these issues, because they exhibit a complex mantle margin and their developmental stages are easily obtained from scallop farms. We investigated the mantle margin of the scallop Nodipecten nodosus (L. 1758) during larval and postmetamorphic development.MethodsA thorough analysis of the mantle margin development in Nodipecten nodosus, from veliger larvae to mature adults, was conducted by means of integrative microscopy techniques, i.e., light, electron, and confocal microscopy.ResultsInitially unfolded, the pallial margin is divided into distal and proximal regions by the periostracum-forming zone. The emergence of the pallial musculature and its neural innervation are crucial steps during bivalve larval development. By the late pediveliger stage, the margin becomes folded, resulting in a bilobed condition (i.e., outer and inner folds), a periostracal groove, and the development of different types of cilia. After metamorphosis, a second outgrowth process is responsible for emergence of the middle mantle fold from the outer surface of the inner fold. Once the three-folded condition is established, the general adult features are rapidly formed.ConclusionsOur data show that the middle mantle fold forms from the outer surface of the inner fold after metamorphosis and that the initial unfolded mantle margin may represent a common condition among bivalves. The first outgrowth process, which gives rise to the outer and inner folds, and the emergence of the pallial musculature and innervation occur during larval stages, highlighting the importance of the larval period for mantle margin morphogenesis in Bivalvia.

Quality and shelf life of the gonad of lion's paw scallop transported and stored whole in refrigeration

The effect of refrigerated 48h transport and 4 days storage on the quality and shelf life of the whole lion's paw scallop Nodipecten subnodosus gonad was evaluated. Proximal composition, adenosine 5´triphosphate (ATP) and related products, K-value, total volatile bases (TVB-N), trimethylamine (TMA-N), pH, fatty acid profile and microbiological analyses were quantified. Gonad holds a significant composition of essential fatty acids while levels of gonadal ATP were initially low; moreover, K-value of the gonad remained constant. With respect to TVB-N and TMA-N, only the former exceeded allowed limits. The pH level showed no significant variation during storage and, despite the high level of TVB-N, according to the TMA-N as well as microbiological analyses it was demonstrated innocuity after 4 days under the transportation and storage conditions utilized.

PAH assessment in the main Brazilian offshore oil and gas production area using semi-permeable membrane devices (SPMD) and transplanted bivalves

The Campos Basin is Brazil's main oil and gas production area. In 2013, more than 50 million cubic meters of produced water (PW) was discharged into these offshore waters. Despite the large volumes of PW that are discharged in the Campos Basin each day, the ecological concern of the chemicals in the PW are not completely understood. Polycyclic aromatic hydrocarbons (PAH) are the most important contributors to the ecological hazards that are posed by discharged PW. This study aimed to evaluate the potential bioaccumulation of PAH using transplanted bivalves (Nodipecten nodosus) and semi-permeable membrane devices (SPMD). The study was conducted in two platforms that discharge PW (P19 and P40). Another platform that does not discharge PW (P25) was investigated for comparison with the obtained results. Time-integrated hydrocarbon concentrations using SPMD and transplanted bivalves were estimated from the seawater near the three platforms. The bioaccumulation of the PAH in the transplanted bivalves at platforms P19 and P40 were up to fivefold greater than the bioaccumulation of the PAH at platform P25. The lowest PAH concentrations were estimated for platform P25 (4.3–6.2ngL−1), and the highest PAH concentrations were estimated for platform P19 (9.2–37.3ngL−1). Both techniques were effective for determining the bioavailability of the PAH and for providing time-integrated hydrocarbon concentrations regarding oil and gas production activities.

Development of the pallial eye in Nodipecten nodosus (Mollusca: Bivalvia): insights into early visual performance in scallops

Scallop pallial eyes have been the most studied optical system in bivalve mollusks. Despite recent advances in our understanding of the function and evolution of scallop eyes, little attention has been focused on eye development and early visual performance. Here, the anatomy and development of pallial eyes were investigated in the scallop Nodipecten nodosus (Linnaeus, 1758) by means of integrative microscopy techniques (i.e., light, electron, and confocal microscopy). After metamorphosis, juvenile scallops bear small papillae that rapidly transform into minute ocular organs on the middle mantle fold. The distal epithelium gradually becomes pigmented, except for the cornea formed at the distal center of the eye. Internally, the optic vesicle comprises undifferentiated cells in the distal region, while mirror plates are secreted at the base of the eye, next to pigmented cells. Within the undifferentiated cell mass, the proximal retina is the first to be formed, followed by the distal retina and then by the lens. In this respect, the late development of the scallop lens from retina precursor cells may represent a unique condition among animal eyes. Adult eyes are characterized by large pigment distribution in the epithelium, tall columnar cornea, and lens above a slightly curved double retina. Whereas the pallial eyes from adult scallops are a complex visual system based on a mirror mechanism to form a focused image on the retina, early eye condition suggests a simple degree of directional photoreception, with no spatial vision.

Antitumor properties of a new non-anticoagulant heparin analog from the mollusk Nodipecten nodosus: Effect on P-selectin, heparanase, metastasis and cellular recruitment.

Inflammation and cancer are related pathologies acting synergistically to promote tumor progression. In both, hematogenous metastasis and inflammation, P-selectin participates in interactions involving tumor cells, platelets, leukocytes and endothelium. Heparin has been shown to inhibit P-selectin and as a consequence it blunts metastasis and inflammation. Some heparin analogs obtained from marine invertebrates are P-selectin inhibitors and do not induce bleeding effects. The present work focuses on the P-selectin blocking activity of a unique heparan sulfate (HS) from the bivalve mollusk Nodipecten nodosus. Initially, we showed that the mollusk HS inhibited LS180 colon carcinoma cell adhesion to immobilized P-selectin in a dose-dependent manner. In addition, we demonstrated that this glycan attenuates leukocyte rolling on activated endothelium and inflammatory cell recruitment in thioglycollate-induced peritonitis in mice. Biochemical analysis indicated that the invertebrate glycan also inhibits heparanase, a key player in cell invasion and metastasis. Experimental metastasis of Lewis lung carcinoma cells was drastically attenuated by the mollusk HS through a mechanism involving inhibition of platelet-tumor-cell complex formation in blood vessels. These data suggest that the mollusk HS is a potential alternative to heparin for inhibiting P-selectin-mediated events such as metastasis and inflammatory cell recruitment.

Apoptosis of hemocytes from lions-paw scallop Nodipecten subnodosus induced with paralyzing shellfish poison from Gymnodinium catenatum

The toxic dinoflagellate Gymnodinium catenatum produces paralyzing shellfish poisons (PSPs) that are consumed and accumulated by bivalves. Previously, we recorded a decrease in hemocytes 24h after injection of PSPs (gonyautoxin 2/3 epimers, GTX2/3) in the adductor muscle in the lions-paw scallop Nodipecten subnodosus. In this work, qualitative and quantitative analyses, in in vivo and in vitro experiments, revealed that the lower count of hemocytes results from cells undergoing typical apoptosis when exposed to GTX 2/3 epimers. This includes visible morphological alterations of the cytoplasmic membrane, damage to the nuclear membrane, condensation of chromatin, DNA fragmentation, and release of DNA fragments into the cytoplasm. Induction of apoptosis was accompanied by phosphatidylserine exposure to the outer cell membrane and activation of cysteine-aspartic proteases, caspase 3 and caspase 8. Addition of an inhibitor of caspase to the medium suppressed activation in hemocytes exposed to the toxins, suggesting that cell death was induced by a caspase-dependent apoptotic pathway. The results are important for future investigation of the scallop's immune system and should provide new insights into apoptotic processes in immune cells of scallops exposed to PSPs.

Sperm motility and fertilization performance ofNodipecten nodosus(L., 1758) exposed at two different cryoprotectants

Cryopreservation is a valuable tool for aquaculture as it provides continuous seed production, regardless of the spawning season of the brood stock. The selection of a suitable cryoprotectant with low toxicity and high water solubility is important to avoid membrane injuries and intracellular ice crystallization. This study has been aimed at the assessment of the toxic effects of two usually applied cryoprotectants, 1-2 propylene glycol (PG) and methanol (MetOH), on spermatozoa of the of lion-paw scallop Nodipecten nodosus, by evaluating the sperm motility and the development of D larvae after fertilization procedure. Sperm was exposed at room temperature (22°C) for 10, 20 and 30 min to different concentration ranges of two cryoprotectants. Regarding the sperm motility, PG5%, PG7%, MetOH4% and MetOH6% did not show differences compared to control (semen incubated in seawater) (P < 0.05). The development of D larvae was not affected by the exposition to PG5%, MetOH 4% and MetOH 6%. These results indicate the potential use of both cryoprotectants for cryopreservation procedures.

Detection of a parasitic amoeba (Order Dactylopodida) in the female gonads of oysters in Brazil.

The impacts of oocyte parasites on the reproductive success of molluscs are largely unknown. In this study, we evaluated the presence of gonad parasites in 6 species of marine bivalve molluscs native to southern Brazil. Cultured bivalves included the mangrove oyster Crassostrea gasar (sometimes called C. brasiliana), the brown mussel Perna perna, the lion's paw scallop Nodipecten nodosus and the wing pearl oyster Pteria hirundo. Another species of mangrove oyster, C. rhizophorae, and the carib pointed venus clam Anomalocardia brasiliana (syn. A. flexuosa) were collected from the wild. Molluscs were collected in winter 2009 and summer 2010 for histopathological and molecular evaluation. An unknown ovarian parasite (UOP) was observed in histopathological sections of female gonads of C. gasar and C. rhizophorae. The UOP possessed features suggestive of amoebae, including an irregular outer membrane, frothy cytoplasm, a nucleus with a prominent central nucleolus and a closely associated basophilic parasome. PCR analysis was negative for Marteilioides chungmuensis, Perkinsus spp. and Paramoeba perurans. However, real-time PCR successfully amplified DNA from oyster gonads when using universal Paramoeba spp. primers. Also, conventional PCR amplified DNA using primers specific for Perkinsela amoebae-like organisms (syn. Perkinsiella), which are considered as endosymbionts of Parameoba spp., previously thought to be the parasome. Our results suggest that this UOP is a species of amoeba belonging to 1 of the 2 families of the order Dactylopodida, possibly related to Paramoeba spp. This study represents the first report of this type of organism in oysters. We found that C. gasar and C. rhizophorae were the most susceptible molluscs to these UOPs.

Effects of Astaxanthin on Reproductive Success in the Tropical ScallopNodipecten nodosus(Linnaeus, 1758)

ABSTRACT In this study, broodstock animals of the tropical scallop Nodipecten nodosus were submitted to maturation trials using two dietary sources of astaxanthin: dried microalgae Haematococcus pluvialis (Algamac AST) and live microalgae obtained from in vitro cultures. The influence of astaxanthin on broodstock maturation was assessed by analyzing stages of gonadal development, accumulation of astaxanthin in sexual organs, animal fecundity, and recovery success rates of larvae and spat. Two experiments (1 and 2) were performed to test dietary concentrations of dried H. pluvialis mixed with live microalgae (Isochrysis sp., Chaetoceros muelleri, and Skeletonema sp.). A third experiment tested 50% dried H. pluvialis with live H. pluvialis versus a diet composed of live C. muelleri. All diets were calculated to a final concentration of 7.5 × 104 algal cells/mL1. In experiments 1 and 2, the 50% Algamac AST diet resulted in a greater (P < 0.05) accumulation of astaxanthin in the female portion of the gonad, a...

Factors Influencing Larval Settlement of the Atlantic Lion's Paw Scallop,Nodipecten nodosus

ABSTRACT Studies were carried out to determine the effect of four factors that may be important to optimize larval settlement of the scallop Nodipecten nodosus in a land-based nursery system: (1) ambient light (tanks were exposed to direct sunlight, kept in partial darkness, and kept in total darkness), (2) necessity for cleaning tanks (whether they should be cleaned daily or left untouched), (3) microalgal diet (ISO, Isochrysis galbana + diatoms; PAV, Pavlova lutheri + diatoms; and a mix, J. galbana + P. lutheri + diatoms fed once or twice a day), and (4) whether broodstock conditioned with an astaxanthin-enriched diet increased settlement. Effects of ambient light did not affect settlement statistically; however, an increase in settlement of 25% was recorded between settlement in tanks kept in total darkness and those exposed to sunlight. Cleaning tanks affected shell height of spat, with larger spat occurring in tanks cleaned every day compared with tanks not cleaned (mean, 1,387.95 (µm). Spat fed with...

Gene discovery in the tropical scallop Nodipecten nodosus: Construction and sequencing of a normalized cDNA library

We report the construction and characterization of a normalized cDNA library from the digestive gland of the marine bivalve Nodipecten nodosus, a commercially valuable tropical scallop. A total of 288 clones were sequenced, and 250 unique sequences were obtained. The cDNA library showed a small sequence redundancy (2.3%) and high numbers of recombinant (99.9%) and independent clones (2.0 × 106 cfu), indicating that the cDNA library generated in this study is a profitable resource for efficient gene discovery for N. nodosus. EST functional annotation by Gene Ontology term assignment revealed the identification of sequences potentially involved in aquaculture and ecotoxicology relevant processes such as apoptosis, growth, lipid metabolism, reproduction, development, response to stress and immunity.

Seasonal change in macromolecular support of reproduction of the tropical scallopNodipecten nodosus: evidence from lipid content and fatty acid profiles of four tissues

Changes in total lipids and fatty acid profiles (FAPs) of gonad, digestive gland, mantle and muscle of the tropical scallopNodipecten nodosuswere examined during coastal upwelling and upwelling relaxation periods. Total lipids were most abundant in digestive gland, and intermediate in female gonad. Multidimensional scaling analysis of similarities (MDS-ANOSIM) and similarity percentage analyses (SIMPER) revealed significant changes of FAPs of the four tissues during the upwelling and upwelling relaxation periods. During both periods, SIMPER analysis revealed an internal similarity index greater than 90% for FAP of each tissue. However, during upwelling the gonad-FAP showed a lower dissimilarity index with the digestive gland-FAP (10), than with muscle-FAP (11) or mantle-FAP (13). In general, during upwelling, the fatty acids 16:0, 18:0, 16:1 n-7, 20:5n-3, 22:6n-3 and total PUFAn-3 explained 42 to 63% of variance between tissues; during upwelling relaxation, these fatty acids together with 14:0 and 18:1 n-7, explained 46 to 64% of variance. During upwelling period, MDS-ANOSIM showed a close association between FAP of digestive gland and gonad, suggesting a rapid transfer of fatty acids between these tissues, and consequently, thatN. nodosusfollows an opportunistic strategy during this period. In contrast, during upwelling relaxation, the slow and continuous fall in total lipid contents of digestive gland (September to November) and the progressive reduction of MDS distances between FAPs of digestive gland and gonad (August until November), suggest a gradual transfer of lipids from digestive gland to gonad to support the gonad development observed during this period. This suggests thatN. nodosusswitches to a conservative strategy during the upwelling relaxation period.