Eupolymnia Nebulosa Research Articles

Nebulosins: Trisubstituted Thiolane Natural Products from the Northeastern Atlantic Annelid Eupolymnia nebulosa.

Using both multi-informative molecular network and score-based approaches as prioritization strategies, the Northeastern Atlantic marine terebellid Eupolymnia nebulosa was selected for in-depth chemical investigation. A family of 16 new metabolites named nebulosins was isolated and structurally characterized from extensive analyses of HRMS/MS and NMR spectroscopic data. Nebulosins feature an unprecedented highly substituted thiolane ring leading to up to four contiguous chiral centers. The relative configurations were assigned through a combination of NOESY analysis, spin-spin coupling constant analysis, and NMR chemical shifts measurements, while the absolute configurations were determined by comparison between experimental and theoretical ECD spectra. This family of natural product exhibits promising antioxidant activities in both ORAC and ROS assays.

Can UV radiation affect benthic deposit-feeders through biochemical alteration of food resources? An experimental study with juveniles of the benthic polychaete Eupolymnia nebulosa

The growth, tentacle development and feeding activity of the benthic polychaete Eupolymnia nebulosa were examined to determine whether UV might affect marine deposit-feeders indirectly through the modification of the nutritional quality of their resources. Since marine invertebrates have higher nutritional requirements during the period following settlement, we tested the effect of UV-altered phytodetritus on freshly settled juveniles of E. nebulosa. Phytodetritus was prepared from cultures of the diatom Skeletonema costatum either grown under or sheltered from UVB radiation. Sterol content of phytodetritus was unmodified by UV radiation. Conversely, phytodetritus was noticeably depleted in polyunsaturated fatty acids. Growth and tentacle development of juveniles fed on altered phytodetritus were reduced by 35% and 15% respectively, suggesting potential deficiencies in essential nutrients. In response to the lower quality of the phytodetritus, juveniles explored a wider area as they search for food, a strategy that could compensate for low food quality.

Activity patterns in the terebellid polychaete Eupolymnia nebulosa assessed using a new image analysis system

The activity and surface sediment displacement by the terebellid polychaete Eupolymnia nebulosa were monitored, using new image acquisition and image analysis procedures. We used a video sensor mounted on a motorized table, to acquire adjacent images of the whole studied aquarium within about 2 s. These images were then grouped within a composite image acquired every 15 s. Consecutive composite images were compared to infer activity and surface sediment displacement. This procedure proved efficient for E. nebulosa as indicated by (1) the continuity of the tentacles within composite images, and (2) the direct comparison of images and detected activities. There were important temporal changes in the relative importance of the three main types of activity: feeding, tube-building and (both partial and total) emergence from the tube, accounting, respectively, for 75, 15 and 10% of the entire experiment duration. Activity intensity (cm2 min-1) was assessed through the surface of pixels with grey levels differing by more than 20 (on a 0–255 scale) between two consecutive images. Feeding was associated with low activity intensity, whereas tube-building and emergence from the tubes were associated with high activity intensities. Surface sediment displacement mostly resulted from tentacle activity both during feeding and tube-building and was almost zero when worms emerged from their tube. We used our experimental set up to assess spatial changes in activity intensity and particle displacements along the tentacles. Most of the activity occurred within the first 4–6 cm from the tube aperture. Particle loss during their transfer along the tentacles preferentially affected larger particles as postulated by the model of particle selection and transport in tentaculate deposit-feeders. Moreover, the speed of the particles along the tentacles correlated negatively with their size. This contributed to increase in the residence time of larger particles on the tentacles and thus, to further enhance their probability of being lost. The size distributions of particles during feeding and tube-building did not differ significantly although visual observations confirmed the preferential use of larger particles for tube-building. This suggests the existence of a sorting step occurring elsewhere than on the tentacles as already demonstrated for spionid polychaetes.

Terebellidae (Polychaeta) from the Mexican Caribbean with description of four new species

Twenty species of Terebellidae Grube, 1850 were recorded and characterized from the Mexican Caribbean, four were newly described: Polycirrus holthei sp. nov., Loimia salazari sp. nov., Neoamphitrite glasbyi sp. nov., and Terebellobranchia mchughae sp. nov. The other species recorded were Lysilla sp., Amphitritides bruneocomata (Ehlers, 1887), Eupolymnia crassicornis (Schmarda, 1861), Eupolymnia nebulosa (Montagu, 1818), Loimia medusa (Savigny, 1818), Loimia minuta Treadwell, 1929, Nicolea modesta Verrill, 1900, Paraeupolymnia carus Young & Kritzler, 1987, Pista palmata (Verrill, 1873), Pista cf. quadrilobata (Augener, 1918), Spinosphaera carrerai Londoño-Mesa, 2003, Spinosphaera hutchingsae Londoño-Mesa, 2003, Streblosoma hartmanae Kritzler, 1971, Terebella verrilli Holthe, 1986, and Thelepus setosus (de Quatrefages, 1865). Materials from the Mexican Caribbean are compared with populations from the Grand Caribbean Region and elsewhere, and with descriptions available in the literature. A taxonomic key for the terebellids recorded from the Grand Caribbean Region is provided.

Early recognition of sediment during settlement of Eupolymnia nebulosa (Polychaeta: Terebellidae) larvae

Analysis of the displacements and activity of larval stages of the terebellid polychaete Eupolymnia nebulosa were carried out on different sediment types collected in the Bay of Banyuls-sur-Mer (western Mediterranean). Results indicated sediment recognition by the larvae. Time devoted to exploration and settlement trials were significantly longer when sediments of similar granulometry had been previously reworked by adults. There were increased responses of settling larvae if the tentacles of adults of the same species had previously been in contact with the tested sediment. The early settlement activity was stronger at the sediment boundaries and increased in the coarse sediment. Our results suggest that larvae are able to recognize biologically bioturbed sediments and modify their behaviour accordingly. There is a larval settlement before the competent stage. Possible consequences of early settlement and the limitation of dispersal in Eupolymnia nebulosa larvae are discussed together with the results of automated measurements of early larval swimming.

The effect of photoperiod on the timing of larval release in the Mediterranean brood-care polychaete Eupolymnia nebulosa (Terebellida)

The effect of light–dark cycle on the timing of larval release from jelly masses of the Mediterranean polychaete Eupolymnia nebulosa (Terebellida) was investigated. The larval emergence from the jelly mass occurs mainly during daylight. Results suggest that the larvae of E. nebulosa do not track the light–dark cycle endogenously.

On the anatomy of the central nervous system and the morphological value of the anterior end appendages of Ampharetidae, Pectinariidae and Terebellidae (Polychaeta)

AbstractEarlier papers dealing with the anatomy of the central nervous system of ampharetids, pectinariids and terebellids were studied. On this basis a re‐investigation appeared necessary: statements in the literature about the structure of the brain and the innervation of the appendages of the anterior end were incomplete and contradictory. In the present paper, the brain, the circum‐oesophageal connectives and the innervation of, inter alia, the tentacular membrane (including the dorsal ridge), the buccal tentacles, the alimentary canal, the nuchal organs and the branchiae (when present) of Amphicteis gunneri, Anobothrus gracilis, Melinna cf. cristata, Pectinaria auricoma, P. belgica, P. koreni, Petta pusilla, Pista cristata, Eupolymnia nebulosa, Thelepus cincinnatus and Polycirrus medusa are described. The results are summarized in schematic diagrams and compared with each other and with the central nervous system of other polychaetes. It is concluded that the ampharetids, the pectinariids and the terebellids bear no antennae and no palps and that their buccal tentacles belong to the alimentary canal. It is emphasized that all attempts to range their cephalic nervous system into previously proposed common and general schemes of ‘the polychaete nervous system’ seem totally fruitless.

A new experimental approach to assess settlement conditions in tube-building polychaetes; biological implications

The present paper proposes an original experimental procedure for studying the processes occurring during larval settlement. This procedure is based on fractionalising the settlement period by isolating part of the available substratum and on using a sediment-marker that dramatically increases the contrast between the tubes and the background. Our approach overcomes two methodological difficulties in the study of tube-building organisms: the temporal isolation of observations that occults the continuity of settlement processes and the lack of precise estimates of the initial number of benthic individuals. Our results demonstrate that, in the tube-building polychaete Eupolymnia nebulosa, settlement in still water consists of an initial passive contact of larvae with the bottom followed by an active reorganisation of the larval distribution. This second phase is connected with the ability of larvae to return to the water column after an initial contact with an unsuitable substratum. © 2000 Ifremer/CNRS/IRD/Éditions scientifiques et médicales Elsevier SAS settlement / recruitment / laboratory experiments / time fractionalising / larva-substratum relationship

An experimental approach to the effects of varying recruitment strategy and food intake on early reproductive traits in a brooding Mediterranean polychaete

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 164:147-156 (1998) - doi:10.3354/meps164147 An experimental approach to the effects of varying recruitment strategy and food intake on early reproductive traits in a brooding Mediterranean polychaete D. Martin1,*, J. H. Cha2, C. Nozais3, M. Bhaud3 1Centre d'Estudis Avançats de Blanes (CSIC), Camí de Santa Bàrbara s/n, E-17300 Blanes (Girona), Spain 2KORDI (Korea Ocean Research and Development Institute), Biological Oceanography Division, ANSAN PO Box 29, Seoul Kr-425-600, Korea 3Laboratoire Arago, Observatoire Océanologique de Banyuls, Université P. et M. Curie (Paris VI), CNRS, URA 117, F-66651 Banyuls-sur-Mer cedex, France *E-mail: dani@ceab.csic.es We examined the effects of reproductive strategy and food intake on the early life history traits of a Mediterranean population of Eupolymnia nebulosa, a deposit-feeding, tubicolous polychaete. In the Mediterranean E. nebulosa are brood-caring, maturity is attained at 2 yr and up to 4 cocoons are produced per female each year, which reduces larval dispersal. In the Atlantic E. nebulosa are free-spawning, they mature in their first year of life and they produce larger offspring, which are released simultaneously. An experimental population grown from spawn collected in the Mediterranean was divided into 2 groups on the basis of the number of tentacles. These 2 groups were taken to simulate the 2 reproductive strategies: worms with 2, 3, 4 and 5 tentacles at the start for the Mediterranean strategy and worms with 3 tentacles at the start for the Atlantic strategy. They were further subdivided and treated with low- and high-energy diets. After 3 mo the only significant difference was a high number of survivors in the group used to simulate Mediterranean recruitment. After 12 mo the high-energy diet increased survival, mean number of tentacles per individual, total tentacles and total worm biomass, and reduced generation time to 1 yr. Although fecundity of these early breeders was lower than that of 2 yr old worms from both laboratory and field populations, this can be entirely attributed to differences in maternal body size. Based on our experimental results, the ecological implications of the reproductive strategy of Mediterranean E. nebulosa are discussed and a new model of resource allocation is proposed for their populations. Terebellidae · Eupolymnia nebulosa · Recruitment strategy · Food intake · Early reproductive traits · NW Mediterranean Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 164. Publication date: April 09, 1998 Print ISSN:0171-8630; Online ISSN:1616-1599 Copyright © 1998 Inter-Research.

Dynamics of Egg Production in Mediterranean Populations of the Terebellid PolychaeteEupolymnia Nebulosa

The dynamics of egg production by a Mediterranean population of the terebellid polychaeteEupolymnia nebulosawas assessed both in the field and in the laboratory between 1992 and 1994. Our results confirm the occurrence of several peaks of jelly mass production at the population level. They show that such peaks result from the production of several broods per individual female (the number of produced broods increasing with female size). Jelly masses produced at the end of the breeding season tend to be smaller and to contain fewer eggs than those produced at the beginning of the breeding season. Worms produced significantly larger jelly masses in 1994 than in 1993 and 1992, without noticeable change in corresponding fecundities. The computation of temporal changes in eggs produced per unit of surface area in the cove of Paulilles shows that most of the eggs are produced during the first two peaks of jelly mass production. These results are discussed relative to the different hypotheses invoked to account for the occurrence of several spawnings in Mediterranean populations of E.nebulosa. It is concluded that no single explanation, such as the allometry constraint hypothesis or heterogeneity in oogenesis rates, can be retained.

Effects of temperature on oocyte growth in the Mediterranean terebellid Eupolymnia nuebulosa (Annelida: Polychaeta)

Eupolymnia nebulosa (Montagu) is a widely distributed terebellid polychaete that builds its tubes on the coastal shelf in areas with mixed soft and hard bottoms. From a long-term survey in the Bay of Banyuls, France (NW Mediterranean), we found an advancement of the timing of the spawning period coincident with a delayed breakdown of the thermocline. We postulate that persistent high temperatures can influence gamete development by stimulating oocyte growth, resulting in earlier spawning. During 1992 and 1993, we used a between-individuals experimental approach to assess the possible effect of temperature on oocyte growth based on: (1) determination of the growing fraction of the oocyte population (i.e. oocyte net growth); (2) identification of differences in oocyte growth-rate among females; (3) comparison of non-significantly different size-distributions of the growing oocyte fraction (net oocyte size-distributions) at the beginning of the experiments with those at the end. No effect of temperature on oocyte growth was detectable at the population level, but a positive individual response to prolonged high temperature was evident. Thus, the lack of a significant response by the population to prolonged high temperature does not imply a lack of individual response. We propose a model of oocyte-growth dynamics based on temperature that incorporates previous observations of extended oogenesis and oocyte growth during periods of both increasing and decreasing temperature and on the scattered pattern of oocyte size-distributions at the onset of spawning.

Modelling of consumption and assimilation in the deposit-feeding polychaete Eupolymnia nebulosa

Modelling of consumption and assimilation in the deposit-feeding polychaete Eupolymnia nebulosa

Change in Setal Pattern during Early Development ofEupolymnia Nebulosa(Polychaeta: Terebellidae) Grown in Simulated Natural Conditions

Eupolymnia nebulosa(Montagu) is a tubicolous worm with its body divided into two regions: thorax with biramous segments and three pairs of gills; abdomen with numerous segments lacking notopodia. The head bears grooved foodgathering tentacles which are not retractile into the mouth. The worm, a typical deposit feeder, lives in mucous tubes encrusted with sand. Although the family Terebellidae is homogeneous in terms of body organization and feeding ecology, there is a remarkable heterogeneity of developmental pattern. In the generaLaniceandLoimia, the life-cycle involves two pelagic stages separated by a short benthic larval stage; in other genera the development is mixed or direct (Bhaudet al.1987; Pechenik, 1979; Caswell, 1981). It is important to study the development of representatives of the family which may reveal the adaptive significance of the different modes of development or may yield information about evolutionary relationships within the family. In several previous papers larval development (Bhaud & Grémare, 1988a,b) and reproductive biology (Bhaudet al.1987) ofE. nebulosahave been reported from the Mediterranean coast. The present article reports observations on juvenile growth and morphological organization in natural conditions. This is the first step to growth rate studies in terms of temperature and food supply (Bhaud, 1988).

Influence of temperature and food supply on development of Eupolymnia nebulosa (Montagu, 1818) (Polychaeta: Terebellidae)

The influence of temperature and food supply on the growth rate of juvenile Eupolymnia nebulosa (Montagu, 1818) was tested in laboratory. The growth rate was positively correlated with temperature: between 10 and 20 °C, in an experiment lasting 38 days, the length of the worms doubled at 20 °C as compared with 10 °C and the number of segments increased from 17 to 25. The growth rate is also sensitive to the amount of the food supply; in the field food is not always available in optimal quantities. As the seawater warms up during the spawning period, which extends from early March to the end of May, and as there is a positive correlation between growth rate and temperature, the range of size variation in the juvenile population becomes narrower in spite of the long spawning period. It is suggested that a narrow range of juvenile sizes may enhance adaptation to spatial spreading and to the competition for food between individuals. It appears that reproductive events are so regulated as to reduce the range of sizes of juveniles emerging from the 3-month spawning period. This adaptation greatly enhances the individual's competitive efficiency and lessens waste in the recruitment period.

Feeding, tube-building and particle-size selection in the terebellid polychaete Eupolymnia nebulosa

The present study was aimed at obtaining new information on the feeding biology of the terebellid polychaete Eupolymnia nebulosa (Montagu). Feeding, tube-building, particle-size selection, and tentacular morphology are described. Experiments were carried out during the fall of 1984 on specimens collected in the vicinity of Banyuls-surmer, France. Feeding activity takes place almost entirely in darkness, and E. nebulosa shows a marked preference for smaller particles when feeding and selects larger ones for tube-building. The control of its activity pattern by light intensity may result in seasonal modification of its energy balance. The mechanisms controlling particle-size selection in this species are discussed.

Mixonephridia or nephromixia in terebellid polychaetes? a clarification

Abstract 1. In recent texts confusion exists in the usage of E.S. Goodrich's terms “mixonephridia” and “nephromixia”, in reference to the segmental organs of polychaete annelids. 2. Goodrich (1945) himself applied the term mixonephridia to the segmental organs that had been described in several families of sedentary polychaetes by Meyer (1887). 3. However, it is shown that the ciliated funnels of these organs in the terebellids Lanice conchilega and Eupolymnia nebulosa in fact contain two distinctly different tissues corresponding to the nephrostomial and coelomostomial components of a nephromixium as defined by Goodrich. 4. Examination of Meyer's text and figures shows that this author had in 1887 already presented clear evidence, apparently overlooked by Goodrich, that in terebellids the ciliated funnels of the segmental organs have the dual composition typical of nephromixia in the sense of the terminology introduced by Goodrich and widely, if at times inaccurately, used today.

A comparative study of reproductive energetics in two populations of the terebellid polychaete Eupolymnianebulosa Montagu with different reproductive modes

In order to compare the reproductive energetics of two populations of the terebellid polychaete Eupolymnia nebulosa Montagu, from Banyuls and from Dinard, the relationship between indices of reproductive output and age has been calculated for the Banyuls population. This relationship led to the elaboration of a method of comparison with the individuals from Dinard which were characterized by different reproductive modes. Such a comparison showed that reproductive allocation was significantly higher in the Dinard population. It has been suggested that differences in the reproductive modes could be the consequences of an increased reproductive output.

Oxygen Uptake with Acute Variation in Temperature and Salinity in Two Coral Reef Polychaetes

. Eupolymnia nebulosa (Terebellidae) and Hermodke carunculata (Amphinomidae) were compared with respect to rates of oxygen consumption in response to acute temperature and salinity variation. E. nebulosa, but not H. carunculata, demonstrated significant temperature sensitivity correlating with the former species' restriction to habitats that are temperature variation. In contrast, H. carunculata occurs where such fluctuation is common. Oxygen uptake in both species was responsive to dilution of the medium whereas only H. carunculata demonstrated insensitivity to increased salinity under most temperature conditions.

Reproductive Value in a Population of Arbitrary Age Distribution

Previous articleNext article No AccessLetters to the EditorsReproductive Value in a Population of Arbitrary Age DistributionJohn H. VandermeerJohn H. Vandermeer Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The American Naturalist Volume 102, Number 928Nov. - Dec., 1968 Published for The American Society of Naturalists Article DOIhttps://doi.org/10.1086/282571 Views: 2Total views on this site Citations: 7Citations are reported from Crossref Copyright 1968 The University of ChicagoPDF download Crossref reports the following articles citing this article:Hisashi Inaba , ( 2017): 75.https://doi.org/10.1007/978-981-10-0188-8_2Dalkhat M. Ediev On the definition of the reproductive value: response to the discussion by Bacaër and Abdurahman, Journal of Mathematical Biology 59, no.55 (Jan 2009): 651–657.https://doi.org/10.1007/s00285-008-0246-3CARLOTTA CASSAI, DANIELA PREVEDELLI Reproductive effort, fecundity and energy allocation in two species of the genus Perinereis (Polychaeta: Nereididae), Invertebrate Reproduction & Development 34, no.2-32-3 (Nov 1998): 125–131.https://doi.org/10.1080/07924259.1998.9652644Mark W. Saunders, Gordon A. McFarlane Age and length at maturity of the female spiny dogfish,Squalus acanthias, in the Strait of Georgia, British Columbia, Canada, Environmental Biology of Fishes 38, no.1-31-3 (Oct 1993): 49–57.https://doi.org/10.1007/BF00842903Mark W. Saunders, Gordon A. McFarlane Age and length at maturity of the female spiny dogfish, Squalus acanthias, in the Strait of Georgia, British Columbia, Canada, (Jan 1993): 49–57.https://doi.org/10.1007/978-94-017-3450-9_5Antoine Gremare A comparative study of reproductive energetics in two populations of the terebellid polychaete Eupolymnia nebulosa Montagu with different reproductive modes, Journal of Experimental Marine Biology and Ecology 96, no.33 (May 1986): 287–302.https://doi.org/10.1016/0022-0981(86)90208-X Graeme Caughley A Comment on Vandermeer's "Pseudo-Reproductive Value", The American Naturalist 104, no.936936 (Oct 2015): 214–215.https://doi.org/10.1086/282652