Journal articles: 'Gammarus pulex'

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Bentley, C. R., and H. Hurd. "Carbohydrate titres in the haemolymph and midgut glands of Gammarus pulex infected with the acanthocephalan Pomphorhynchus laevis." Journal of Helminthology 70, no. 2 (June 1996): 103–7. http://dx.doi.org/10.1017/s0022149x00015236.

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AbstractAn examination of the effects of Pomphorhynchus laevis cystacanths on the haemolymph and midgut gland carbohydrate titres of its intermediate host, Gammarus pulex (Crustacea) was undertaken. In the haemolymph, infection with cystacanths did not alter the relationship between haemolymph carbohydrate titres and body wet weight. However, in the midgut glands, infection did alter the relationship between gammarid wet weight and titres of glucose and trehalose (P<0.05, Chow test). The linear relationship between gammarid size and midgut glycogen titre was also significantly altered by infection. Thus circulating carbohydrate titres are unaltered in infected gammarids but storage ones are. The changes in carbohydrate titres and the relationship between individual titres and body wet weight are discussed, especially regarding parasite index.

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Könemann, Sarah, Yvonne Müller, Daniel Tschentscher, Martin Krauss, Pedro Inostroza, Ira Brückner, Johannes Pinnekamp, Sabrina Schiwy, and Henner Hollert. "Combination of In Situ Feeding Rate Experiments and Chemical Body Burden Analysis to Assess the Influence of Micropollutants in Wastewater on Gammarus pulex." International Journal of Environmental Research and Public Health 16, no. 5 (March 11, 2019): 883. http://dx.doi.org/10.3390/ijerph16050883.

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Wastewater discharge is one of the main sources of micropollutants within the aquatic environment. To reduce the risks for the aquatic environment, the reduction of the chemical load of wastewater treatment plant effluent is critical. Based on this need, additional treatment methods, such as ozonation, are currently being tested in several wastewater treatment plants (WWTPs). In the present study, effects were investigated using in situ feeding experiments with Gammarus pulex and body burden analyses of frequently detected micropollutants which used a Quick Easy Cheap Effective Rugged and Safe (QuEChERS) multi-residue method to quantify internal concentrations in collected gammarids. Information obtained from these experiments complemented data from the chemical analysis of water samples and bioassays, which predominantly cover hydrophilic substances. When comparing up- and downstream feeding rates of Gammarus pulex for seven days, relative to the WWTPs, no significant acute effects were detected, although a slight trend of increased feeding rate downstream of the WWTP Aachen-Soers was observed. The chemical load released by the WWTP or at other points, or by diffuse sources, might be too low to lead to clear acute effects on G. pulex. However, some compounds found in wastewater are able to alter the microbial community on its leaves, leading to an increase in the feeding rate of G. pulex. Chemical analysis of internal concentrations of pollutants in the tissues of collected gammarids suggests a potential risk for chronic effects with the chemicals imidacloprid, thiacloprid, carbendazim, and 1H-benzotriazole when exceeding the critical toxic unit value of −3. This study has demonstrated that a combination of acute testing and measurement of the internal concentration of micropollutants that might lead to chronic effects is an efficient tool for investigating river systems, assuming all relevant factors (e.g., species or season) are taken into account.

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Bentley, C. R., and H. Hurd. "Pomphorhynchus laevis (Acanthocephala): elevation of haemolymph protein concentrations in the intermediate host, Gammarus pulex (Crustacea: Amphipoda)." Parasitology 107, no. 2 (August 1993): 193–98. http://dx.doi.org/10.1017/s0031182000067305.

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SUMMARYComparisons were made between the protein concentrations and protein profiles of uninfected Gammarus pulex and those infected with cystacanths of Pomphorhynchus laevis. Comparisons of the extractable haemolymph volumes from uninfected and infected G. pulex, when related to host tissue weight, showed that there was no difference in the host tissue/haemolymph volume ratio between infected and uninfected individuals. SDS-PAGE of haemolymph samples resolved 36 bands of protein, the major components being band 6(19 kDa) and 21(33 kDa). Densitometric analysis of haemolymph samples showed that infected gammarids had total protein concentrations elevated by 84%. The (88 kDa) subunit was identified as the monomer of the respiratory protein haemocyanin. This band was significantly elevated in infected individuals (one-way ANOVA P < 0.001); increasing from 30 to 45% of the total haemolymph proteins.

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Kullmann, Harald, Timo Thünken, Sebastian A. Baldauf, Theo C. M. Bakker, and Joachim G. Frommen. "Fish odour triggers conspecific attraction behaviour in an aquatic invertebrate." Biology Letters 4, no. 5 (July 2008): 458–60. http://dx.doi.org/10.1098/rsbl.2008.0246.

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Group living has evolved as an adaptation to predation in many animal species. In a multitude of vertebrates, the tendency to aggregate varies with the risk of predation, but experimental evidence for this is less well known in invertebrates. Here, we examine the tendency to aggregate in the freshwater amphipod Gammarus pulex in the absence and presence of predator fish odour. Without fish odour, the gammarids showed no significant tendency to aggregate. In contrast to this, in fish-conditioned water, they significantly preferred to stay close to conspecifics. Predation risk can, thus, influence gammarids social behaviour.

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Yardy, Lewis, and Amanda Callaghan. "Microplastic and Organic Fibres in Feeding, Growth and Mortality of Gammarus pulex." Environments 8, no. 8 (August 3, 2021): 74. http://dx.doi.org/10.3390/environments8080074.

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Microplastic fibres (MPFs) are a major source of microplastic pollution, most are released during domestic washing of synthetic clothing. Organic microfibres (OMF) are also released into the environment by the same means, with cotton and wool being the most common in the UK. There is little empirical evidence to demonstrate that plastic fibres are more harmful than organic fibres if ingested by freshwater animals such as Gammarus pulex. Using our method of feeding Gammarus MPFs embedded in algal wafers, we compared the ingestion, feeding behaviour and growth of Gammarus exposed to 70 µm sheep wool, 20 µm cotton, 30 µm acrylic wool, and 50 µm or 100 µm human hair, and 30 µm cat hair at a concentration of 3% fibre by mass. Gammarus would not ingest wafers containing human hair, or sheep wool fibres. Given the choice between control wafers and those contaminated with MPF, cat hair or cotton, Gammarus spent less time feeding on MPF but there was no difference in the time spent feeding on OMFs compared to the control. Given a choice between contaminated wafers, Gammarus preferred the OMF to the MPF. There were no significant differences in growth or mortality among any of the treatments. These results conclude that MPFs are less likely to be ingested by Gammarus if alternative food is available and are not more harmful than OMFs.

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ÖZBEK, MURAT, and BELGİN ÇAMUR-ELİPEK. "Gammarus kesanensis sp. nov., a new blind amphipod species from Turkey (Amphipoda, Gammaridae), with a key to eyeless Gammarus species of Europe." Zootaxa 2399, no. 1 (March 15, 2010): 51. http://dx.doi.org/10.11646/zootaxa.2399.1.5.

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A new blind species of freshwater amphipod, Gammarus kesanensis sp. nov., collected from Erikli Fountain, Keşan, Turkey, is described and illustrated. The new species belongs to Gammarus pulex- group and is the fourth blind species of the group reported from Europe and Turkey. A detailed morphological description and illustrations of the new species are given and differences from related species are discussed. In addition, a key to the blind/eyeless species of Gammarus genus of Europe is presented.

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Birkhead, T. R., and S. Pringle. "Multiple mating and paternity in Gammarus pulex." Animal Behaviour 34, no. 2 (April 1986): 611–13. http://dx.doi.org/10.1016/s0003-3472(86)80134-8.

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Ponton, F., T. Lefevre, C. Lebarbenchon, F. Thomas, H. D. Loxdale, L. Marché, L. Renault, M. J. Perrot-Minnot, and D. G. Biron. "Do distantly related parasites rely on the same proximate factors to alter the behaviour of their hosts?" Proceedings of the Royal Society B: Biological Sciences 273, no. 1603 (August 14, 2006): 2869–77. http://dx.doi.org/10.1098/rspb.2006.3654.

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Phylogenetically unrelated parasites often increase the chances of their transmission by inducing similar phenotypic changes in their hosts. However, it is not known whether these convergent strategies rely on the same biochemical precursors. In this paper, we explored such aspects by studying two gammarid species ( Gammarus insensibilis and Gammarus pulex ; Crustacea: Amphipoda: Gammaridae) serving as intermediate hosts in the life cycle of two distantly related parasites: the trematode, Microphallus papillorobustus and the acanthocephalan, Polymorphus minutus . Both these parasite species are known to manipulate the behaviour of their amphipod hosts, bringing them towards the water surface, where they are preferentially eaten by aquatic birds (definitive hosts). By studying and comparing the brains of infected G. insensibilis and G. pulex with proteomics tools, we have elucidated some of the proximate causes involved in the parasite-induced alterations of host behaviour for each system. Protein identifications suggest that altered physiological compartments in hosts can be similar (e.g. immunoneural connexions) or different (e.g. vision process), and hence specific to the host–parasite association considered. Moreover, proteins required to alter the same physiological compartment can be specific or conversely common in both systems, illustrating in the latter case a molecular convergence in the proximate mechanisms of manipulation.

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MacNeil, Calum, and Jaimie T. A. Dick. "The enemy of my enemy is my friend: intraguild predation between invaders and natives facilitates coexistence with shared invasive prey." Biology Letters 10, no. 8 (August 2014): 20140398. http://dx.doi.org/10.1098/rsbl.2014.0398.

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Understanding and predicting the outcomes of biological invasions is challenging where multiple invader and native species interact. We hypothesize that antagonistic interactions between invaders and natives could divert their impact on subsequent invasive species, thus facilitating coexistence. From field data, we found that, when existing together in freshwater sites, the native amphipod Gammarus duebeni celticus and a previous invader G. pulex appear to facilitate the establishment of a second invader, their shared prey Crangonyx pseudogracilis. Indeed, the latter species was rarely found at sites where each Gammarus species was present on its own. Experiments indicated that this may be the result of G. d. celticus and G. pulex engaging in more intraguild predation (IGP) than cannibalism; when the ‘enemy’ of either Gammarus species was present, that is, the other Gammarus species, C. pseudogracilis significantly more often escaped predation. Thus, the presence of mutual enemies and the stronger inter- than intraspecific interactions they engage in can facilitate other invaders. With some invasive species such as C. pseudogracilis having no known detrimental effects on native species, and indeed having some positive ecological effects, we also conclude that some invasions could promote biodiversity and ecosystem functioning.

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Redondo-Hasselerharm, P. E., G. Vink, D. M. Mitrano, and A. A. Koelmans. "Metal-doping of nanoplastics enables accurate assessment of uptake and effects on Gammarus pulex." Environmental Science: Nano 8, no. 6 (2021): 1761–70. http://dx.doi.org/10.1039/d1en00068c.

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The combination of nanoplastic metal doping and biodynamic modeling allows for accurate assessment of bioaccumulation and effects on Gammarus pulex, even in a complex environmental matrix such as sediment.

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FRANCESCHI, N., T. RIGAUD, Y. MORET, F. HERVANT, and L. BOLLACHE. "Behavioural and physiological effects of the trophically transmitted cestode parasite, Cyathocephalus truncatus, on its intermediate host, Gammarus pulex." Parasitology 134, no. 12 (July 19, 2007): 1839–47. http://dx.doi.org/10.1017/s0031182007003228.

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SUMMARYSome parasites with complex life-cycles are able to manipulate the behaviour of their intermediate hosts in a way that increases their transmission to the next host. Gammarids infected by the tapeworm Cyathocephalus truncatus (Cestoda: Spathebothriidea) are known to be more predated by fish than uninfected ones, but potential behavioural manipulation by the parasite has never been investigated. In this study, we tested the hypothesis that C. truncatus is able to manipulate the behaviour of one of its intermediate hosts, Gammarus pulex (Crustacea: Amphipoda). To assess if any behavioural change was linked to other phenotypic alterations, we also measured the immunity of infected and uninfected individuals and investigated the pathogenic effects of the parasite. Infected gammarids were significantly less photophobic than uninfected ones, but no effect of infection on the level of immune defence was found. The results on survival, swimming activity and oxygen consumption suggest that the parasite also has various pathogenic effects. However, the alteration in host phototaxis was not correlated to some of these pathogenic effects. Therefore, we propose that the modification in host reaction to light is a behavioural manipulation, explaining the previously observed increase of gammarid predation rate.

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Paidere, Jana, Aija Brakovska, Linda Bankovska, and Dāvis Gruberts. "Changes in the distribution of amphipods in the Daugava River, Latvia." Zoology and Ecology 29, no. 2 (July 30, 2019): 99–102. http://dx.doi.org/10.35513/21658005.2019.2.4.

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Scientific information on amphipods and other peracaridan crustaceans in Latvian inland waters is insufficient. Therefore investigations of these animals are indispensable, especially because of the ongoing biological invasions of Ponto-Caspian amphipods causing changes in macroinvertebrate assemblages. Our recent investigation revealed that the alien amphipod Gammarus varsoviensis dominates amphipods in the upper courses of the Daugava River, whereas the other alien amphipod Pontogammarus robustoides prevails in the lower reaches of the river. Both these Ponto-Caspian amphipods were found co-occurring with the indigenous Gammarus pulex in the middle course of the Daugava River upstream from the Pļaviņas Reservoir. We predict that in the future the indigenous G. pulex will be fully exterminated by alien amphipods in the Latvian part of the Daugava River.

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ÖZBEK, MURAT, and SULEYMAN BALIK. "A new freshwater amphipod species, Gammarus topkarai sp. nov., from Turkey (Amphipoda: Gammaridae), with a key for Turkish freshwater Gammarus species." Zootaxa 2073, no. 1 (April 16, 2009): 45–56. http://dx.doi.org/10.11646/zootaxa.2073.1.4.

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A new species of freshwater Amphipod, Gammarus topkarai sp. nov., collected from Ivriz Creek, Tarsus Province, South Anatolia, is described and illustrated. The new species belongs to Gammarus pulex-group and shows similar characteristic features with Gammarus agrarius G. S. Karaman, 1973. Absence of well developed dorsal elevations on the urosome segments, smaller body length and relatively lower endopod/exopod ratio of third uropod are the most obvious features differ from G. agrarius. A detailed morphological description and illustrations of new species are given and differences from related species are discussed. An updated identification key of Gammarus taxa reported from Turkey, up to date, was also presented.

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Iacarella, Josephine C., Emma J. Hudgins, Jaimie T. A. Dick, and Anthony Ricciardi. "Predatory behaviour of an invasive amphipod in response to varying conspecific densities under higher-order predation risk." Canadian Journal of Fisheries and Aquatic Sciences 75, no. 1 (January 2018): 131–40. http://dx.doi.org/10.1139/cjfas-2016-0417.

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Behavioural responses of invasive animals to biotic interactions can inform predictions of their consumptive impacts; however, such biotic contexts are often overlooked. Here, we assessed the interacting effect of conspecific and higher-order predation risk on the per capita consumption and behaviours of the invasive freshwater amphipod Gammarus pulex, using field microcosm and video-recorded lab experiments in Northern Ireland. Gammarus pulex exhibited higher per capita consumption in the presence of conspecifics, owing to reduced handling time of prey, regardless of fish presence and despite reduced swimming time and increased time spent physically interacting with each other. Consumption was lower in the presence of fish in the field, and handling time decreased with greater amphipod densities in the presence of fish cue in the lab. Our results show that impacts of G. pulex are independently influenced by conspecifics and predation risk, whereas handling time revealed an interacting effect of conspecific density and predation risk. Further assessments of the responses of invasive animals to biotic interactions could help explain variability in their impacts at local spatial scales.

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Stoffels, B. E. M. W., J. S. Tummers, G. Van Der Velde, D. Platvoet, H. W. M. Hendriks, and R. S. E. W. Leuven. "Assessment of predatory ability of native and non-native freshwater gammaridean species: A rapid test with water fleas as prey." Current Zoology 57, no. 6 (December 1, 2011): 836–43. http://dx.doi.org/10.1093/czoolo/57.6.836.

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Abstract Predation rate with relation to species, sex and water temperature was tested among four different gammaridean species: Dikerogammarus villosus, Gammarus roeselii, Gammarus pulex and Gammarus fossarum. Tests were performed in microcosms in climate-controlled rooms at five different temperatures. Daphnia magna, a common water flea, served as prey. On average D. villosus showed the highest consumption rate of Daphnia magna over the entire temperature range, followed in decreasing order by G. p u le x , G. roeselii and G. fossarum. The predation rate of all species showed a distinct peak at 20°C. Correction of predation rates for body size gave somewhat different results. D. villosus is then still the most predatory of all gammaridean species tested followed by G. pulex, G. fossarum and G. roeselii. The outcome of the Daphnia tests is consistent with results of other studies with different prey. This supports that the Daphnia test is a good and quick indicator of the predatory abilities in gammaridean species at varying temperatures, and allows the prediction of how changing temperature regimes influence invasion impacts.

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Scheepmaker, Maarten. "Morphological and Genetic Differentiation of Gammarus Stupendus Pinkster, 1983 in the Massif de la Sainte Baume, France." Bijdragen tot de Dierkunde 57, no. 1 (1987): 1–18. http://dx.doi.org/10.1163/26660644-05701001.

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Morphologically distinct populations of the Gammarus pulex group which should be attributed to at least three species applying morphological criteria postulated by Karaman & Pinkster (1977) have been reported in the Massif de la Sainte Baume (southern France). These populations proved to be completely interfertile and thus were considered conspecific. This group of populations, in which three major forms A, B and C were distinguished, has been described as Gammarus stupendus Pinkster, 1983.

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Tain, Luke, Marie-Jeanne Perrot-Minnot, and Frank Cézilly. "Differential influence of Pomphorhynchus laevis (Acanthocephala) on brain serotonergic activity in two congeneric host species." Biology Letters 3, no. 1 (December 19, 2006): 69–72. http://dx.doi.org/10.1098/rsbl.2006.0583.

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The physiological mechanisms by which parasites with complex life cycles manipulate the behaviour of their intermediate hosts are still poorly understood. In Burgundy, eastern France, the acanthocephalan parasite Pomphorhynchus laevis inverses reaction to light in its amphipod host Gammarus pulex , but not in Gammarus roeseli , a recent invasive species. Here, we show that this difference in manipulation actually reflects a difference in the ability of the parasite to alter brain serotonergic (5-HT) activity of the two host species. Injection of 5-HT in uninfected individuals of both host species was sufficient to inverse reaction to light. However, a difference in brain 5-HT immunocytochemical staining levels between infected and uninfected individuals was observed only in G. pulex . Local adaptation of the parasite to the local host species might explain its inability to manipulate the behaviour and nervous system of the invasive species.

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Birkhead, T. R., and K. Clarkson. "Mate Selection and Precopulatory Guarding in Gammarus pulex." Zeitschrift für Tierpsychologie 52, no. 4 (April 26, 2010): 365–80. http://dx.doi.org/10.1111/j.1439-0310.1980.tb00724.x.

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Khan, F. R., N. R. Bury, and C. Hogstrand. "Copper and zinc detoxification in Gammarus pulex (L.)." Journal of Experimental Biology 215, no. 5 (February 8, 2012): 822–32. http://dx.doi.org/10.1242/jeb.062505.

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Gismondi, E., and J. P. Thomé. "Transcriptome of the freshwater amphipod Gammarus pulex hepatopancreas." Genomics Data 8 (June 2016): 91–92. http://dx.doi.org/10.1016/j.gdata.2016.04.002.

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Mhamed, W., A. Hargreaves, and C. Mills. "The relative toxicity of palladium toward Gammarus pulex." Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology 163 (September 2012): S24. http://dx.doi.org/10.1016/j.cbpa.2012.05.075.

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Sherbakov, D. Yu. "ON THE PHYLOGENY OF LAKE BAIKAL AMPHIPODS IN THE LIGHT OF MITOCHONDRIAL AND NUCLEAR DNA SEQUENCE DATA." Crustaceana 72, no. 8 (1999): 911–19. http://dx.doi.org/10.1163/156854099503816.

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AbstractTwo DNA sequence data sets, one from the nuclear 18S rRNA gene (520 bp long), the other from the mitochondrial COI gene (540 bp), are used to characterize the evolutionary history of the endemic Baikalian amphipod species assemblage. The observed differentiation suggests that the initial radiation of Baikalian lineages was ancient, probably older than the emergence of the initial large paleolake within the current lake basin in the mid-Tertiary. The mtDNA data suggest a principal division between the smooth fossorial genus Micruropus and the remaining Baikalian amphipod taxa included in the study. The monophyly of the Baikalian taxa with respect to the non-Baikalian Gammarus cannot be conclusively inferred from the mitochondrial sequences. The 18S rRNA data, however, suggest that the pelagic Baikalian species Macrohectopus branickii is closer to the European Gammarus pulex than to any other gammarid studied, and give an indication of a polyphyletic origin of the Baikalian amphipod fauna. Also, within the Baikalian assemblage, the major genera with strongly developed body armature, Acanthogammarus and Pallasea, may be polyphyletic. Deux ensembles de donnees de sequences du DNA, l'un concernant le 18S rRNA nucleaire (520 pb), l'autre le gene mitochondrial COI (540 pb) sont utilises pour caracteriser l'histoire evolutive de l'assemblage des especes d'amphipodes endemiques du Baikal. La differenciation observee suggere que la radiation initiale des lignees baikaliennes est ancienne, probablement plus ancienne que l'emergence du grand paleolac initial a l'interieur du bassin lacustre du tertiaire moyen. Les donnees du mtDNA suggerent une division principale entre le genre fouisseur lisse Micruropus et les taxa baikaliens restants, inclus dans l'etude. La monophylie des taxons baikaliens par rapport aux Gammarus non baikaliens ne peut pas etre deduite de facon concluante des sequences mitochondriales. Les donnees du 18S rRNA, cependant, suggerent que l'espece pelagique baikalienne Macrohectopus branickii est plus proche du Gammarus pulex europeen que de n'importe quel autre gammaride etudie, et donnent une indication de l'origine polyphyletique de la faune baikalienne d'amphipodes. De meme, dans l'assemblage baikalien, les genres majeurs aavec une armature du corps fortement developpee, Acanthogammarus et Pallasea , pourraient etre ppolyphyletiques.

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GALIPAUD, MATTHIAS, ZOÉ GAUTHEY, and LOÏC BOLLACHE. "Pairing success and sperm reserve of male Gammarus pulex infected by Cyathocephalus truncatus (Cestoda: Spathebothriidea)." Parasitology 138, no. 11 (August 3, 2011): 1429–35. http://dx.doi.org/10.1017/s0031182011001247.

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SUMMARYManipulative parasites with complex life cycles are known to induce behavioural and physiological changes in their intermediate hosts. Cyathocephalus truncatus is a manipulative parasite which infects Gammarus pulex as intermediate host. G. pulex males display pre-copulatory mate guarding as a response to male-male competition for access to receptive females. In this paper, we tested the influence that C. truncatus-infection might have on male G. pulex sperm number and pairing success. We considered 3 classes of G. pulex males in our experiments: (i) uninfected males found paired in the field, (ii) uninfected males found unpaired in the field, or (iii) infected males found unpaired in the field. Both infected males and uninfected unpaired males paired less with a new female than uninfected paired males did. Furthermore, infected males appear to be at a strong disadvantage when directly competing for females with a healthy rival male, and had fewer sperm in their testes. We discuss the potential effect of male and female mating strategies on such male host mating alteration.

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HEKMATARA, MARYAM, ALIREZA SARI, and MOHAMMAD-HADI HEIDARY BALADEHI. "Two new Gammarus species (Crustacea: Amphipoda: Gammaridae) from Zagros Mountains, Iran." Zootaxa 2894, no. 1 (May 27, 2011): 39. http://dx.doi.org/10.11646/zootaxa.2894.1.3.

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The present study tries to focus on describing two new species belonging to genus Gammarus from western Iran along the Zagros Mountains range. The most remarkable feature of Gammarus hegmatanensis sp. n. is the shape of epimeral plate 3, which is sharply pointed posteriorly with a distinct lobate anterior margin. This species has some similarities with and differences from some other species of Gammarus pulex–group such as G. parthicus and G. syriacus. The other species, G. sirvannus sp. n. with elongated eyes is similar to G. duebeni, G. lobifer, G. balutchi and G. loeffleri, but it shows prominent morphological differences and a distinct geographical distribution from these species. These new findings shed more light on the information available on amphipod fauna of Iran.

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SERDAR, Osman, Nuran CIKCIKOĞLU YILDIRIM, Şule TATAR, and Numan YILDIRIM. "Antioxidant Enzyme Responses to Lead Exposure of Gammarus pulex." Journal of Anatolian Environmental and Animal Sciences 4, no. 2 (August 24, 2019): 216–20. http://dx.doi.org/10.35229/jaes.571909.

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MacNeil, Calum, Nina J. Fielding, Kevin D. Hume, Jaimie T. A. Dick, Robert W. Elwood, Melanie J. Hatcher, and Alison M. Dunn. "Parasite altered micro-distribution of Gammarus pulex (Crustacea: Amphipoda)." International Journal for Parasitology 33, no. 1 (January 2003): 57–64. http://dx.doi.org/10.1016/s0020-7519(02)00229-1.

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Adams, Jonathan, and Paul J. Greenwood. "Environmental Constraints On Mate Choice in Gammarus Pulex (Amphipoda)." Crustaceana 50, no. 1 (1986): 45–52. http://dx.doi.org/10.1163/156854085x00062.

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Elwood, Robert, Julie Gibson, and Susan Neil. "The amorous Gammarus: size assortative mating in G. pulex." Animal Behaviour 35, no. 1 (February 1987): 1–6. http://dx.doi.org/10.1016/s0003-3472(87)80203-8.

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Fanton, Hadrien, Evelyne Franquet, Maxime Logez, and Nicolas Kaldonski. "Pomphorhynchus laevis manipulates Gammarus pulex behaviour despite salt pollution." Freshwater Biology 65, no. 10 (June 23, 2020): 1718–25. http://dx.doi.org/10.1111/fwb.13573.

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Dalhoff, Kristoffer, Michele Gottardi, Åsmund Rinnan, Jes Jessen Rasmussen, and Nina Cedergreen. "Seasonal sensitivity of Gammarus pulex towards the pyrethroid cypermethrin." Chemosphere 200 (June 2018): 632–40. http://dx.doi.org/10.1016/j.chemosphere.2018.02.153.

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Scheepmaker, Maarten, Frits van der Meer, and Sjouk Pinkster. "Genetic Differentiation of the Iberian Amphiodus Gammarus Ibericus Margalef, 1951 and G. Gauthieri S. Karaman, 1935, with Reference to some Related Species in France." Bijdragen tot de Dierkunde 58, no. 2 (1988): 205–26. http://dx.doi.org/10.1163/26660644-05802003.

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Populations of five related species belonging to the Gammarus pulex group from the Iberian Peninsula and southern France have been studied electrophoretically at 21 enzyme loci. Morphologically distinct forms from the same side of the Pyrenees proved to be genetically more similar than morphologically very similar forms from opposite sides of this barrier.

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BAILLY, YANN, FRANK CÉZILLY, and THIERRY RIGAUD. "Stage-dependent behavioural changes but early castration induced by the acanthocephalan parasite Polymorphus minutus in its Gammarus pulex intermediate host." Parasitology 145, no. 3 (August 23, 2017): 260–68. http://dx.doi.org/10.1017/s0031182017001457.

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SUMMARYMultidimensionality in parasite-induced phenotypic alterations (PIPA) has been observed in a large number of host–parasite associations, particularly in parasites with complex life cycles. However, it is still unclear whether such a syndrome is due to the successive activation of independent PIPAs, or results from the synchronous disruption of a single mechanism. The aim of the present study was to investigate the onset and progression of two PIPAs (a behavioural alteration: reversion of geotaxis, and castration) occurring in the crustacean amphipod Gammarus pulex infected with the acanthocephalan Polymorphus minutus, at different parasite developmental stages. Modifications of geotaxis in hosts differed according to the parasite developmental stage. Whereas the cystacanth stage induced a negative geotaxis (exposing the gammarid to predation by birds, the definitive hosts), the acanthella stage, not yet infective for the definitive host, induced a stronger positive geotaxis (presumably protecting gammarids from bird predation). In contrast, castration was almost total at the acanthella stage, with no significant variation in the intensity according to parasite maturation. Finally, no significant correlation was found between the intensity of behavioural changes and the intensity of castration. We discuss our results in relation with current views on the evolution of multidimensionality in PIPA.

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MAZZI, D., and T. C. M. BAKKER. "A Predator's Dilemma: prey choice and parasite susceptibility in three-spined sticklebacks." Parasitology 126, no. 4 (April 2003): 339–47. http://dx.doi.org/10.1017/s0031182003003019.

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The acanthocephalan parasite Pomphorhynchus laevis is transmitted by a suitable intermediate host such as the amphipod Gammarus pulex to its definitive fish host. Parasite-induced alterations in both appearance and behaviour concur to render infected gammarids more vulnerable to predation, thus promoting parasite transmission. Experimental infection of laboratory bred full- and half-sib groups of three-spined sticklebacks (Gasterosteus aculeatus) provided evidence that the parasite imposes a survival cost proportional to the severity of infection on its final host. Variation among sibships in the susceptibility to infection was consistent. When given a choice, fish consumed significantly more infected than uninfected prey. Overall, more resistant fish did not prey upon infected gammarids more often than did relatively susceptible fish. Only fish with a relatively high physical condition properly adjusted prey selection to the extent of their parasite susceptibility, thus exploiting the enhanced profitability of infected prey.

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KALDONSKI, N., M. J. PERROT-MINNOT, S. MOTREUIL, and F. CÉZILLY. "Infection with acanthocephalans increases the vulnerability of Gammarus pulex (Crustacea, Amphipoda) to non-host invertebrate predators." Parasitology 135, no. 5 (March 27, 2008): 627–32. http://dx.doi.org/10.1017/s003118200800423x.

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SUMMARYPhenotypic alterations induced by parasites in their intermediate hosts often result in enhanced trophic transmission to appropriate final hosts. However, such alterations may also increase the vulnerability of intermediate hosts to predation by non-host species. We studied the influence of both infection with 3 different acanthocephalan parasites (Pomphorhynchus laevis, P. tereticollis, and Polymorphus minutus) and the availability of refuges on the susceptibility of the amphipod Gammarus pulex to predation by 2 non-host predators in microcosms. Only infection with P. laevis increased the vulnerability of amphipods to predation by crayfish, Orconectes limosus. In contrast, in the absence of refuges, the selectivity of water scorpions, Nepa cinerea, for infected prey was significant and did not differ according to parasite species. When a refuge was available for infected prey, however, water scorpion selectivity for infected prey differed between parasite species. Both P. tereticollis- and P. laevis-infected gammarids were more vulnerable than uninfected ones, whereas the reverse was true of P. minutus-infected gammarids. These results suggest that the true consequences of phenotypic changes associated with parasitic infection in terms of increased trophic transmission of parasites deserve further assessment.

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Cornet, Stéphane, Nathalie Franceschi, Loïc Bollache, Thierry Rigaud, and Gabriele Sorci. "Variation and covariation in infectivity, virulence and immunodepression in the host–parasite association Gammarus pulex – Pomphorhynchus laevis." Proceedings of the Royal Society B: Biological Sciences 276, no. 1676 (September 2, 2009): 4229–36. http://dx.doi.org/10.1098/rspb.2009.1299.

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Parasites often manipulate host immunity for their own benefit, either by exacerbating or suppressing the immune response and this may directly affect the expression of parasite virulence. However, genetic variation in immunodepression, which is a prerequisite to its evolution, and the relationship between immunodepression and virulence, have rarely been studied. Here, we investigated the variation among sibships of the acanthocephalan parasite, Pomphorhynchus laevis , in infecting and in immunodepressing its amphipod host, Gammarus pulex . We also assessed the covariation between infectivity, parasite-induced immune depression and host mortality (parasite virulence). We found that infectivity, the intensity of immunodepression and virulence were variable among parasite sibships. Infectivity and the level of immunodepression were not correlated across parasite sibships. Whereas infectivity was unrelated to host mortality, we found that gammarids that were exposed to the parasite sibships that immunodepressed their hosts the most survived better. This positive covariation between host survival and immunodepression suggests that gammarids exposed to the less immunodepressive parasites could suffer from damage imposed by a higher activity of the phenoloxidase.

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Shahid, Naeem, Jeremias Martin Becker, Martin Krauss, Werner Brack, and Matthias Liess. "Adaptation of Gammarus pulex to agricultural insecticide contamination in streams." Science of The Total Environment 621 (April 2018): 479–85. http://dx.doi.org/10.1016/j.scitotenv.2017.11.220.

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Elwood, Robert W., and Jaimie T. A. Dick. "Assessments and Decisions During Mate Choice in Gammarus Pulex (Amphipoda)." Behaviour 109, no. 3-4 (1989): 235–45. http://dx.doi.org/10.1163/156853989x00259.

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AbstractMale Gammarus pulex preferentially enter precopulatory mate guarding with large females close to moulting. The interactions of males and females were observed in an attempt to elucidate the process by which males assess females and, further, to determine how such information gathering influences mating decisions. Males which encountered single females, which had recently been experimentally separated from other males, grabbed and held those females in a perpendicular hold prior to establishing the precopulatory hold. The higher the reproductive quality of the female the more rapid was the male decision to move into the perpendicular hold but this was followed by an increased level of abdomen flexing and antennae touching. Once precopula was established, higher quality females received more stroking with the free gnathopods. When two females were encountered, some males simply took the first contacted and this resulted in random pairing. Other males, however, demonstrated the ability to sequentially sample as well as simultaneously compare females and, if this occurred, they almost invariably took the higher quality female. Discrimination between two females was more rapid as the difference in their qualities increased whereas males engaged in more grabbing and holding when females were of similar moult stages. The data show that assessment of female size and moult stage occurs early in the interaction, whereas subsequent activities such as flexing and stroking are probably involved in courtship, possibly serving to pacify females.

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Ward, Paul I. "Micro-habitat segregation and the mating system of Gammarus pulex." Animal Behaviour 45, no. 1 (January 1993): 191–92. http://dx.doi.org/10.1006/anbe.1993.1019.

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Crane, Mark. "Population characteristics of Gammarus pulex (L.) from five English streams." Hydrobiologia 281, no. 2 (April 1994): 91–100. http://dx.doi.org/10.1007/bf00006438.

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Naylor, Caroline, Lorraine Maltby, and Peter Calow. "Scope for growth in Gammarus pulex, a freshwater benthic detritivore." Hydrobiologia 188-189, no. 1 (December 1989): 517–23. http://dx.doi.org/10.1007/bf00027819.

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Duband, S., F. Forest, Y. Gaillard, J. M. Dumollard, M. Debout, and M. Péoc’h. "Macroscopic, histological and toxicological aspects of early Gammarus pulex scavenging." Forensic Science International 209, no. 1-3 (June 2011): e16-e22. http://dx.doi.org/10.1016/j.forsciint.2011.03.025.

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Tain, Luke, Marie-Jeanne Perrot-Minnot, and Frank Cézilly. "Altered host behaviour and brain serotonergic activity caused by acanthocephalans: evidence for specificity." Proceedings of the Royal Society B: Biological Sciences 273, no. 1605 (September 26, 2006): 3039–45. http://dx.doi.org/10.1098/rspb.2006.3618.

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Manipulative parasites can alter the phenotype of intermediate hosts in various ways. However, it is unclear whether such changes are just by-products of infection or adaptive and enhance transmission to the final host. Here, we show that the alteration of serotonergic activity is functionally linked to the alteration of specific behaviour in the amphipod Gammarus pulex infected with acanthocephalan parasites. Pomphorhynchus laevis and, to a lesser extent, Pomphorhynchus tereticollis altered phototactism, but not geotactism, in G. pulex , whereas the reverse was true for Polymorphus minutus . Serotonin (5-hydroxytryptamine, 5-HT) injected to uninfected G. pulex mimicked the altered phototactism, but had no effect on geotactism. Photophilic G. pulex infected with P. laevis or P. tereticollis showed a 40% increase in brain 5-HT immunoreactivity compared to photophobic, uninfected individuals. In contrast, brain 5-HT immunoreactivity did not differ between P. minutus -infected and uninfected G. pulex . Finally, brain 5-HT immunoreactivity differed significantly among P. tereticollis -infected individuals in accordance with their degree of manipulation. Our results demonstrate that altered 5-HT activity is not the mere consequence of infection by acanthocephalans but is specifically linked to the disruption of host photophobic behaviour, whereas the alteration of other behaviours such as geotactism may rely on distinct physiological routes.

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Knight, Clarke A., Jocelyne M. R. Hughes, and Tim Johns. "What drives non-native amphipod distributions in the River Thames? The role of habitat and human activity on species abundance." Crustaceana 90, no. 4 (2017): 399–416. http://dx.doi.org/10.1163/15685403-00003665.

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Increasing colonization of non-native amphipod species in the River Thames, United Kingdom, has altered aquatic ecology and called existing management practices into question. We studied the distribution patterns of recent non-native (Dikerogammarus haemobaphes (Eichwald, 1841)), established non-native (Crangonyx pseudogracilis (Bousfield, 1958)), and native amphipod (Gammarus pulex (Linnaeus, 1758)) species, as well as habitat and human influences across 84 sites in the upper Thames catchment. Our findings showed widespread distribution and density of G. pulex relative to D. haemobaphes, suggesting that the full impact of the current spread has yet to be felt since its 2012 introduction. Different habitat utilization patterns are explained through habitat partitioning: both D. haemobaphes and C. pseudogracilis occupied vegetative habitats, not pebble/gravel habitats where the native G. pulex was most often found. The association between D. haemobaphes and boating presence implies that effective biosecurity would be best focused on boat traffic in the Thames and Cherwell rivers.

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Scheepmaker, Maarten, and Jan van Dalfsen. "Genetic differentiation in Gammarus fossarum and G. caparti (Crustacea, Amphipoda) with reference to G. pulex pulex in northwestern Europe." Bijdragen tot de Dierkunde 59, no. 3 (1989): 127–39. http://dx.doi.org/10.1163/26660644-05903001.

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Genetic differentiation among G. fossarum Koch, 1835 from different stations in Germany, Switzerland, Belgium and northern France, and the closely related Belgian form G. caparti Pètre-Stroobants, 1980 was investigated by electrophoresis at 20 enzyme loci. Although morphologically variable, geographically distant populations of G. cf. fossarum were hitherto considered conspecific. In the present study, populations of G. cf. fossarum and G. caparti were examined with reference to G. pulex pulex as an estimate for genetic differentiation at the species level. With G. p. pulex as a standard, genetic differentiation among geographically distant populations of G. cf. fossarum is occasionally observed at species level. The populations of G. caparti studied were shown to be genetically very similar to certain populations of G. fossarum. The taxonomic status of G. caparti and the genetically distinct forms of G. fossarum is discussed.

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Morritt, David, and John I. Spicer. "The Culture of Eggs and Embryos of Amphipod Crustaceans: Implications For Brood Pouch Physiology." Journal of the Marine Biological Association of the United Kingdom 76, no. 2 (May 1996): 361–76. http://dx.doi.org/10.1017/s0025315400030605.

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A technique is described for the in vitro culture of the eggs and embryos of amphipod crustaceans. The technique was used, with mixed success, to culture the eggs of four species of amphipod (Gammarus duebeni, Orchestia gammarellus, Gammarus pulex and Echinogammarus pirloti) through to hatching. Eggs of the brackish water G. duebeni showed good hatching success in culture (70–75%) over a wide range of experimental salinities (75–1250 mOsm kg1). The eggs of O. gammarellus showed higher mortality rates in culture (compared with G. duebeni), especially in more dilute salinities (300 mOsm kg1) in which they swelled greatly prior to disintegration. Survival and true growth (as distinct from osmotic swelling) of O. gammarellus embryos in dilute salinities were significantly im-proved by introducing embryos into culture at a later stage of development. Antibiotic treatment had no demonstrable effect on embryo survival or growth. Whilst difficult to culture using this method, the eggs of the fresh water G. pulex showed best hatching success on a very dilute saline medium (~40 mOsm kg1). The results are discussed in relation to the development of embryonic osmoregulation, the implications for brood pouch function and the potential for female control of the embryonic environment, especially in semi-terrestrial species.

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Perrot-Minnot, Marie-Jeanne, Kevin Sanchez-Thirion, and Frank Cézilly. "Multidimensionality in host manipulation mimicked by serotonin injection." Proceedings of the Royal Society B: Biological Sciences 281, no. 1796 (December 7, 2014): 20141915. http://dx.doi.org/10.1098/rspb.2014.1915.

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Manipulative parasites often alter the phenotype of their hosts along multiple dimensions. ‘Multidimensionality’ in host manipulation could consist in the simultaneous alteration of several physiological pathways independently of one another, or proceed from the disruption of some key physiological parameter, followed by a cascade of effects. We compared multidimensionality in ‘host manipulation’ between two closely related amphipods, Gammarus fossarum and Gammarus pulex, naturally and experimentally infected with Pomphorhynchus laevis (Acanthocephala), respectively. To that end, we calculated in each host–parasite association the effect size of the difference between infected and uninfected individuals for six different traits (activity, phototaxis, geotaxis, attraction to conspecifics, refuge use and metabolic rate). The effects sizes were highly correlated between host–parasite associations, providing evidence for a relatively constant ‘infection syndrome’. Using the same methodology, we compared the extent of phenotypic alterations induced by an experimental injection of serotonin (5-HT) in uninfected G. pulex to that induced by experimental or natural infection with P. laevis . We observed a significant correlation between effect sizes across the six traits, indicating that injection with 5-HT can faithfully mimic the ‘infection syndrome’. This is, to our knowledge, the first experimental evidence that multidimensionality in host manipulation can proceed, at least partly, from the disruption of some major physiological mechanism.

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ZAMANPOORE, MEHRDAD, MANFRED POECKL, MICHAL GRABOWSKI, and FRIEDRICH SCHIEMER. "Two new sympatric species of freshwater Gammarus (Crustacea: Amphipoda) from Southern Zagros Region, Iran." Zootaxa 2136, no. 1 (June 19, 2009): 21–39. http://dx.doi.org/10.11646/zootaxa.2136.1.2.

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Gammarus zagrosensis n. sp. and Gammarus sepidannus n. sp., both from Gammarus pulex–group, are described from Sepidan County, Fars Province. They inhabit mountainous springs and were found co-occuring in some localities. Many clear morphological differences were recognized, including the setation of the second antenna and pereopods, length of antennal gland cone, postero-inferior protruding lobe and postero-distal corner setation in the basis of P6–7, endopodite/exopodite ratios of uropod 3, dorsal elevation of urosomites, and setation of lower distal margin of epimeral plates 2 and 3. Gammarus zagrosensis is distinguished from G. pseudosyriacus by having setae on the distal segments of pereopod 5–7, a less pointed epimeral plate 2, posterior-inferior corner setae, and the longer setae on uropod 3. The closest species to G. sepidannus are G. balutchi and G. lobifer, the most evident differences of which are the eye size, setosity of first antennal peduncles and flagellum of second antenna, length of gland cone, and uropod rami length ratios. Comparison of the head cuticular micro-structures gives more arguments for separating the two new species from each other, as well as from the previously studied, related species.

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Kaldonski, Nicolas, Marie-Jeanne Perrot-Minnot, Raphaël Dodet, Guillaume Martinaud, and Frank Cézilly. "Carotenoid-based colour of acanthocephalan cystacanths plays no role in host manipulation." Proceedings of the Royal Society B: Biological Sciences 276, no. 1654 (September 16, 2008): 169–76. http://dx.doi.org/10.1098/rspb.2008.0798.

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Manipulation by parasites is a catchy concept that has been applied to a large range of phenotypic alterations brought about by parasites in their hosts. It has, for instance, been suggested that the carotenoid-based colour of acanthocephalan cystacanths is adaptive through increasing the conspicuousness of infected intermediate hosts and, hence, their vulnerability to appropriate final hosts such as fish predators. We revisited the evidence in favour of adaptive coloration of acanthocephalan parasites in relation to increased trophic transmission using the crustacean amphipod Gammarus pulex and two species of acanthocephalans, Pomphorhynchus laevis and Polymorphus minutus . Both species show carotenoid-based colorations, but rely, respectively, on freshwater fish and aquatic bird species as final hosts. In addition, the two parasites differ in the type of behavioural alteration brought to their common intermediate host. Pomphorhynchus laevis reverses negative phototaxis in G. pulex , whereas P. minutus reverses positive geotaxis. In aquaria, trout showed selective predation for P. laevis -infected gammarids, whereas P. minutus -infected ones did not differ from uninfected controls in their vulnerability to predation. We tested for an effect of parasite coloration on increased trophic transmission by painting a yellow–orange spot on the cuticle of uninfected gammarids and by masking the yellow–orange spot of infected individuals with inconspicuous brown paint. To enhance realism, match of colour between painted mimics and true parasite was carefully checked using a spectrometer. We found no evidence for a role of parasite coloration in the increased vulnerability of gammarids to predation by trout. Painted mimics did not differ from control uninfected gammarids in their vulnerability to predation by trout. In addition, covering the place through which the parasite was visible did not reduce the vulnerability of infected gammarids to predation by trout. We discuss alternative evolutionary explanations for the origin and maintenance of carotenoid-based colorations in acanthocephalan parasites.

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LAGRUE, C., A. GÜVENATAM, and L. BOLLACHE. "Manipulative parasites may not alter intermediate host distribution but still enhance their transmission: field evidence for increased vulnerability to definitive hosts and non-host predator avoidance." Parasitology 140, no. 2 (October 15, 2012): 258–65. http://dx.doi.org/10.1017/s0031182012001552.

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SUMMARYBehavioural alterations induced by parasites in their intermediate hosts can spatially structure host populations, possibly resulting in enhanced trophic transmission to definitive hosts. However, such alterations may also increase intermediate host vulnerability to non-host predators. Parasite-induced behavioural alterations may thus vary between parasite species and depend on each parasite definitive host species. We studied the influence of infection with 2 acanthocephalan parasites (Echinorhynchus truttae and Polymorphus minutus) on the distribution of the amphipod Gammarus pulex in the field. Predator presence or absence and predator species, whether suitable definitive host or dead-end predator, had no effect on the micro-distribution of infected or uninfected G. pulex amphipods. Although neither parasite species seem to influence intermediate host distribution, E. truttae infected G. pulex were still significantly more vulnerable to predation by fish (Cottus gobio), the parasite's definitive hosts. In contrast, G. pulex infected with P. minutus, a bird acanthocephalan, did not suffer from increased predation by C. gobio, a predator unsuitable as host for P. minutus. These results suggest that effects of behavioural changes associated with parasite infections might not be detectable until intermediate hosts actually come in contact with predators. However, parasite-induced changes in host spatial distribution may still be adaptive if they drive hosts into areas of high transmission probabilities.

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Galipaud, Matthias, François-Xavier Dechaume-Moncharmont, Abderrahim Oughadou, and Loïc Bollache. "Does foreplay matter? Gammarus pulex females may benefit from long-lasting precopulatory mate guarding." Biology Letters 7, no. 3 (November 10, 2010): 333–35. http://dx.doi.org/10.1098/rsbl.2010.0924.

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Precopulatory mate guarding (PCMG) is generally assumed to be costly for both sexes. However, males may gain by displaying long-lasting mate guarding under strong male–male competition. Surprisingly, the potential for females to benefit from being held by males has been largely overlooked in previous studies. In Gammarus pulex , an amphipod crustacean, PCMG lasts several weeks, yet females are described as bearing only cost from such male mating strategy. We investigated potential female benefits by assessing the effect of mate guarding on her intermoult duration. Unpaired females had longer intermoult duration than paired females. Intermoult duration clearly decreased when paired females engaged in early and long-lasting mate guarding. In addition, short intermoults and long-lasting mate guarding had no effect on egg number. These results highlight a potential benefit associated with PCMG for G. pulex females, suggesting that the strength of an intersexual conflict over its duration may be overestimated.

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Journal articles on the topic 'Gammarus pulex'

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