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Zhonge Hou - One of the best experts on this subject based on the ideXlab platform.

  • seven new freshwater species of Gammarus from southern china crustacea amphipoda gammaridae
    ZooKeys, 2018
    Co-Authors: Zhonge Hou, Shuangyan Zhao
    Abstract:

    Seven new species of the genus Gammarus are described and illustrated from southern China. The new species Gammarus vallecula Hou & Li, sp. n., G. qinling Hou & Li, sp. n., G. zhigangi Hou & Li, sp. n. and G. jidutanxian Hou & Li, sp. n. are characterized by inner ramus of uropod III half the length of outer ramus. Gammarus longdong Hou & Li, sp. n. is characterized by inner ramus of uropod III 0.9 times as long as outer ramus. Gammarus mosuo Hou & Li, sp. n. is characterized by pereopods V-VII with long setae on anterior margins and both rami of uropod III armed with simple setae. Gammarus caecigenus Hou & Li, sp. n. can be distinguished from other species by eyes absent. DNA barcodes of the new species are documented as proof of molecular differences between species. A key to the new species and a map of their distributions are provided.

  • four new Gammarus species from tibetan plateau with a key to tibetan freshwater gammarids crustacea amphipoda gammaridae
    ZooKeys, 2018
    Co-Authors: Zhonge Hou
    Abstract:

    Four new species of the genus Gammarus are described and illustrated from Tibetan Plateau. Gammarus altussp. n. and G. limosussp. n. are characterized by pereopods III-IV with a few short setae and uropod III with marginal spines accompanied by short setae. Gammarus kangdingensissp. n. and G. gonggaensissp. n. are characterized by pereopods III-IV with long straight setae on posterior margins and inner ramus of uropod III 0.4 times as long as outer ramus. Detailed morphological comparisons with related species are discussed. A key to 15 Gammarus species from the Tibetan Plateau and a map of their distributions are provided.

  • two new Gammarus species and a new name crustacea amphipoda gammaridae from northwest china
    Zootaxa, 2017
    Co-Authors: Shuangyan Zhao, Kaibaryer Meng, Zhonge Hou
    Abstract:

    Two new species of the genus Gammarus are described and illustrated from Northwest China. A new species name Gammarus tianshan nom. nov. is proposed to replace G. montanus Hou et al. , 2004. Gammarus simplex sp. nov. from Altay, Xinjiang, is characterized by uropod III with simple setae on both rami and urosomite I only with setae on dorsal margin. Gammarus glaber sp. nov. from Qinghai, is characterized by uropod III with few simple and plumose setae. Detailed morphological description and differences from related species are discussed. A distribution map of the new species and related species is provided.

  • diversification of low dispersal crustaceans through mountain uplift a case study of Gammarus amphipoda gammaridae with descriptions of four novel species
    Zoological Journal of the Linnean Society, 2014
    Co-Authors: Zhonge Hou
    Abstract:

    Lineages with low dispersal ability are geographically restricted. We used freshwater Gammarus to test this hypothesis. Sequences of two mitochondrial (cytochrome c oxidase subunit I and 16S) and two nuclear (28S and cytosolic heat-shock protein) genes were obtained for seven species distributed in 28 localities along the Luliang and Taihang mountains in China. Phylogenetic analyses showed that Gammarus species were grouped into two clades, one from the Luliang range and the other from the Taihang range. Each clade was further divided into three or four species, showing a congruent pattern with geographical vicariance. Divergence time estimation indicated that the split between the two clades coincided with the uplift of the Taihang Mountains at the boundary of Oligocene/Miocene. Most speciation events may have been driven by massive uplifting of the Luliang and Taihang mountains from the late Miocene to early Pliocene. Additionally, four new species are described: Gammarus incoercitus sp. nov., Gammarus benignus sp. nov., Gammarus monticellus sp. nov., and Gammarus pisinnus sp. nov. The new species are compared with related species in this area and a key to these species is provided. © 2014 The Linnean Society of London

  • ten new Gammarus species crustacea amphipoda gammaridae from yunnan guizhou plateau china
    Zootaxa, 2013
    Co-Authors: Zhonge Hou
    Abstract:

    Ten new species of the genus Gammarus are described from Yunnan-Guizhou Plateau, Southwest China, including Gam­marus amabilis sp. nov. , G. citatus sp. nov. , G. echinatus sp. nov. , G. egregius sp. nov. , G. eliquatus sp. nov. , G. hirtellus sp. nov. , G. margcomosus sp. nov. , G. rivalis sp. nov. , G. silendus sp. nov. and G. tranquillus sp. nov . Four of them are stygobite and with no eyes. Detailed illustrations and comparisons with related species are presented. A key to all species from Yunnan-Guizhou Plateau are given.

Murat Ozbek - One of the best experts on this subject based on the ideXlab platform.

  • Gökçeada içsularının amphipoda (Crustacea: Malacostraca) faunası
    Ege University, 2017
    Co-Authors: Murat Ozbek, Nurcan Özkan
    Abstract:

    Ege Denizi’nin önemli adalarından olan Gökçeada iç sularında dağılım gösteren Amphipod türlerinin tespit edilmesi amacıyla, farklı tarihlerde adadaki 17 lokaliteden toplanmış olan örnekler incelenmiştir. Örnekler 500 µm göz açıklığındaki el kepçeleri ile toplanmış olup, sahada %4’lük formaldehit solüsyonu içinde fikse edilmişlerdir. Çalışma sonucunda, örnekleme yapılan istasyonlarda Gammaridae ve Talitridae familyalarına ait toplam 3 türün [Gammarus komareki Schäferna 1922, Gammarus aequicauda (Martynov, 1931) ve Orchestia mediterranea Costa, 1853] dağılım gösterdiği tespit edilmiştir. Tespit edilen türler Gökçeada’dan ilk defa kayıt edilmektedir

  • marmara ve pasalimani adalari ile kapidag yarimadasi icsularinin gammaridae amphipoda faunasi
    Ege Journal of Fisheries and Aquatic Sciences, 2015
    Co-Authors: Murat Ozbek, Hasan H Ozturk, Nurcan Özkan
    Abstract:

    Marmara Denizi’nin onemli adalarindan olan Marmara ve Pasalimani adalari ile Kapidag Yarimadasi icsularinda dagilim gosteren Gammaridae turlerinin tespit edilmesi amaciyla, 24-28 Agustos 2010 tarihleri arasinda 21 farkli istasyondan orneklemeler yapilmistir. Yapilan calismalar sonucunda, ornekleme yapilan istasyonlarda Gammaridae familyasinin Gammarus genusuna ait toplam 3 taksonun [ Gammarus pulex pulex (Linnaeus, 1758), Gammarus uludagi Karaman, 1975, Gammarus aequicauda (Martynov, 1931)] dagilim gosterdigi tespit edilmistir. Tespit edilen taksonlarin tumu ulkemizden daha onceden kayit edilmis olan turlerdir.

  • marmara ve pasalimani adalari ile kapidag yarimadasi icsularinin gammaridae amphipoda faunasi gammaridae amphipoda fauna of the inland waters of marmara and pasalimani islands and kapidag peninsula
    2015
    Co-Authors: Murat Ozbek, Hasan H Ozturk, Nurcan Özkan
    Abstract:

    In order to determine the freshwater Gammaridae fauna of the Marmara and Pasalimani islands which are among the main islands of Sea of Marmara, and Kapidag Peninsula, samplings were carried out at 21 different localities between 24 and 28 August 2010. As a result, three species belonging to Gammaridae (Gammarus pulex pulex (Linnaeus, 1758), Gammarus uludagi Karaman, 1975, Gammarus aequicauda (Martynov, 1931)) were determined. All of the determined species were previously recorded from Turkey.

  • Gammarus komareki aznavensis subsp nov a new amphipod subspecies from iran amphipoda gammaridae
    Turkish Journal of Zoology, 2014
    Co-Authors: Murat Ozbek, Hamidreza Rasouli
    Abstract:

    A new subspecies of freshwater amphipod, Gammarus komareki aznavensis subsp. nov., collected from Aznav County (Khalkhal-Ardabil), northwestern Iran, is described and illustrated. The new subspecies belongs to the Gammarus pulex -group and has characteristic features similar to Gammarus komareki. Shorter flagellum of antenna 1, kidney-shaped and bigger eyes, more setose outer margin of the exopodite of uropod 3, and shorter endopodite of uropod 3 are the most obvious features that differ from G. komareki . A detailed morphological description and illustrations of the new subspecies are given and differences from related species are discussed.

  • Gammarus baysali sp nov a new freshwater amphipod species from turkey amphipoda gammaridae
    Turkish Journal of Zoology, 2013
    Co-Authors: Murat Ozbek, Levent Yurga, Okan Kulkoyluoğlu
    Abstract:

    A new species of freshwater amphipod, Gammarus baysali sp. nov., collected from Cumayani Cave (Zonguldak Province, Turkey) is described and illustrated. The new species belongs to the Gammarus pulex-group. The most discriminant characters of this species are the minute eyes, densely setose fifth peduncle and flagellar segments of antenna 2, elongated pereopods, and setose anterior margins of pereopod 5 to 7. Additionally, the palp of right maxilla 1 has 4 setae along its outer margin. A detailed morphological description and illustrations of the new species are provided, and differences from related species are discussed.

Nurcan Özkan - One of the best experts on this subject based on the ideXlab platform.

Calum Macneil - One of the best experts on this subject based on the ideXlab platform.

  • the dynamics of predation on Gammarus spp crustacea amphipoda
    Biological Reviews, 2007
    Co-Authors: Calum Macneil, Jaimie T. A. Dick, Robert W. Elwood
    Abstract:

    Gammarus spp. (Crustacea: Amphipoda) are widespread throughout a diverse range of marine, freshwater and estuarine}brackish habitats, often dominating benthic macroinvertebrate communities in terms of both numbers and}or biomass. Gammarus spp. are the dominant macroinvertebrate prey items of many fish, whether as a seasonal food source or a year-round staple. Selective predation by fish on Gammarus spp. is often linked to parasitism and the body size of the prey. Gammarus spp. populations are under increasing threat from both pollution and replacement}displacement by introduced species. Loss of populations and species invasions}replacements could have significant impacts on native predator species if the predator(s) cannot successfully adapt their feeding patterns to cope with non-indigenous Gammarus prey species. Despite this, many fish predation studies do not identify Gammarus prey to species level. This lack of precision could be important, as Gammarus spp. exhibit wide variations in physiochemical tolerances, habitat requirements, abilities to invade and susceptibility to replacement. Although rarely acknowledged, the impacts of nonpiscean predators (particularly macroinvertebrates) on Gammarus prey species may frequently be stronger than those exerted by fish. A major aim of this review is to ascertain the current importance of Gammarus as a prey species, such that the implications of changes in Gammarus spp. populations can be more accurately assessed by interested groups such as ecologists and fisheries managers.We also review the dynamics of Gammarus spp. as prey to a diverse array of mammals, birds, amphibians, insects, flatworms, other crustaceans such as crabs and crayfish and, perhaps most importantly, other Gammarus spp.

  • the trophic ecology of freshwater Gammarus spp crustacea amphipoda problems and perspectives concerning the functional feeding group concept
    Biological Reviews, 2007
    Co-Authors: Calum Macneil, Jaimie T. A. Dick, Robert W. Elwood
    Abstract:

    Gammarus spp. are widespread throughout a diverse range of freshwater habitats and can be the dominant part of many benthic macroinvertebrate assemblages, in terms of both numbers and}or biomass. Although the vast majority of studies have emphasized the herbivorous nature of Gammarus spp. and their ‘shredder’ functional feeding group (FFG) classification, we show that a far wider food base is exploited than has been previously acknowledged. This ‘plasticity’ as herbivore}predator is linked to the success of Gammarus spp. in persisting in and colonizing}invading disturbance-prone ecosystems. Intraguild predation and cannibalism are more common than previously realized. This behaviour appears to be a causal mechanism in many amphipod species replacements. Additionally, Gammarus spp. are major predators of other members of the macroinvertebrate community. Furthermore, while many studies have emphasized fish predation on Gammarus spp., we illustrate how this fish:amphipod, predator:prey interaction may be a two-way process, with Gammarus spp. themselves preying upon juvenile and wounded}trapped fish. We urge that a new realism be adopted towards the trophic ecology of Gammarus spp. and their role as predators and prey and that previously established FFG assumptions of both the food and the feeder be questioned critically.

  • invasion by the amphipod Gammarus pulex alters community composition of native freshwater macroinvertebrates
    Diversity and Distributions, 2006
    Co-Authors: David W Kelly, Jaimie T. A. Dick, Calum Macneil, Roberta J E Bailey, Robbie A Mcdonald
    Abstract:

    Assessing the effects of invading species on native community structure is often confounded by environmental factors and weakened by lack of replicated, long-term pre- and post-invasion monitoring. Here, we uncouple the community effects of a freshwater amphipod invader from environmental differences. In Irish rivers, the introduced Gammarus pulex replaces the native Gammarus duebeni celticus. However, the River Lissan in Northern Ireland is dissected by a weir that has slowed the upstream invasion by G. pulex. This allowed us in 2000 to sample three contiguous 150-m reaches that were (1) G. pulex dominated; (2) mixed Gammarus spp.; and (3) G. duebeni celticus only. In 2003, we resampled these reaches and one additional of mixed Gammarus species and one with only G. duebeni celticus further upstream. In temperature, conductivity, and pH, there were statistically significant but no biologically relevant differences among the five reaches of 2003, and between the three reaches surveyed in both years. Although there was evidence of recovery in macroinvertebrate diversity and richness in invaded reaches between years, continued upstream invasion was associated with sustained reductions in these community metrics as compared to un-invaded sites. Community ordination indicated (1) different associations of community composition attributed to the distribution, abundance, and biomass of the invader; and (2) increasing similarity of invaded communities over time. The impact mechanisms of G. pulex on macroinvertebrate community composition may include predation and competition. The consequences of the observed community changes for ecosystem functioning require further investigation.

  • the predatory impact of the freshwater invader dikeroGammarus villosus on native Gammarus pulex crustacea amphipoda influences of differential microdistribution and food resources
    Journal of Zoology, 2005
    Co-Authors: Calum Macneil, Dirk Platvoet
    Abstract:

    Predation between invading and native species can produce patterns of exclusion and coexistence. DikeroGammarus villosus , a Ponto-Caspian amphipod species, has invaded many central European freshwaters in the past decade, replacing native Gammarus amphipod species. For instance, the arrival of D. villosus in Holland has been accompanied by the decline of Gammarus duebeni and G. tigrinus populations within invaded systems. This study examined what may happen when D. villosus eventually encounters native Dutch populations of Gammarus pulex , and how factors such as microhabitat and food resource availability could contribute to a future species replacement or coexistence. A laboratory simulation of a lake/pooled area of river indicated that G. pulex and D. villosus differed in distribution within the same habitat, and showed that although the distribution of the native differed in the presence of the invader, the presence of the native had no effect on the distribution of the invader. Gammarus pulex suffered severe intraguild predation (IGP) from D. villosus in mixed species treatments with no reciprocal predation of D. villosus by G. pulex . This IGP occurred regardless of whether no alternative food resource was available (91% of the G. pulex population eliminated after 7 days), or alternative foods/prey were available to excess, such as leaf material (85%), chironomids (77%) or fish food flakes (74%). We conclude that although differential microdistribution of the two species could promote coexistence, the presence of alternative foods/prey resources, merely slow the rate of IGP and replacement of the native by the invader. Our study joins one of an increasing number emphasizing the potential damaging impacts of D. villosus on native communities.

  • the replacement of a native freshwater amphipod by an invader roles for environmental degradation and intraguild predation
    Canadian Journal of Fisheries and Aquatic Sciences, 2004
    Co-Authors: Calum Macneil, Jaimie T. A. Dick, John Prenter, Mark Briffa, Nina J Fielding, Gillian E Riddell, Melanie J Hatcher, Alison M Dunn
    Abstract:

    We assessed the extent to which an invader, Gammarus pulex (Crustacea: Amphipoda), has replaced a native, Gammarus duebeni celticus, over a 13-year period in a European river system and some of the...

Jaimie T. A. Dick - One of the best experts on this subject based on the ideXlab platform.

  • the dynamics of predation on Gammarus spp crustacea amphipoda
    Biological Reviews, 2007
    Co-Authors: Calum Macneil, Jaimie T. A. Dick, Robert W. Elwood
    Abstract:

    Gammarus spp. (Crustacea: Amphipoda) are widespread throughout a diverse range of marine, freshwater and estuarine}brackish habitats, often dominating benthic macroinvertebrate communities in terms of both numbers and}or biomass. Gammarus spp. are the dominant macroinvertebrate prey items of many fish, whether as a seasonal food source or a year-round staple. Selective predation by fish on Gammarus spp. is often linked to parasitism and the body size of the prey. Gammarus spp. populations are under increasing threat from both pollution and replacement}displacement by introduced species. Loss of populations and species invasions}replacements could have significant impacts on native predator species if the predator(s) cannot successfully adapt their feeding patterns to cope with non-indigenous Gammarus prey species. Despite this, many fish predation studies do not identify Gammarus prey to species level. This lack of precision could be important, as Gammarus spp. exhibit wide variations in physiochemical tolerances, habitat requirements, abilities to invade and susceptibility to replacement. Although rarely acknowledged, the impacts of nonpiscean predators (particularly macroinvertebrates) on Gammarus prey species may frequently be stronger than those exerted by fish. A major aim of this review is to ascertain the current importance of Gammarus as a prey species, such that the implications of changes in Gammarus spp. populations can be more accurately assessed by interested groups such as ecologists and fisheries managers.We also review the dynamics of Gammarus spp. as prey to a diverse array of mammals, birds, amphibians, insects, flatworms, other crustaceans such as crabs and crayfish and, perhaps most importantly, other Gammarus spp.

  • the trophic ecology of freshwater Gammarus spp crustacea amphipoda problems and perspectives concerning the functional feeding group concept
    Biological Reviews, 2007
    Co-Authors: Calum Macneil, Jaimie T. A. Dick, Robert W. Elwood
    Abstract:

    Gammarus spp. are widespread throughout a diverse range of freshwater habitats and can be the dominant part of many benthic macroinvertebrate assemblages, in terms of both numbers and}or biomass. Although the vast majority of studies have emphasized the herbivorous nature of Gammarus spp. and their ‘shredder’ functional feeding group (FFG) classification, we show that a far wider food base is exploited than has been previously acknowledged. This ‘plasticity’ as herbivore}predator is linked to the success of Gammarus spp. in persisting in and colonizing}invading disturbance-prone ecosystems. Intraguild predation and cannibalism are more common than previously realized. This behaviour appears to be a causal mechanism in many amphipod species replacements. Additionally, Gammarus spp. are major predators of other members of the macroinvertebrate community. Furthermore, while many studies have emphasized fish predation on Gammarus spp., we illustrate how this fish:amphipod, predator:prey interaction may be a two-way process, with Gammarus spp. themselves preying upon juvenile and wounded}trapped fish. We urge that a new realism be adopted towards the trophic ecology of Gammarus spp. and their role as predators and prey and that previously established FFG assumptions of both the food and the feeder be questioned critically.

  • invasion by the amphipod Gammarus pulex alters community composition of native freshwater macroinvertebrates
    Diversity and Distributions, 2006
    Co-Authors: David W Kelly, Jaimie T. A. Dick, Calum Macneil, Roberta J E Bailey, Robbie A Mcdonald
    Abstract:

    Assessing the effects of invading species on native community structure is often confounded by environmental factors and weakened by lack of replicated, long-term pre- and post-invasion monitoring. Here, we uncouple the community effects of a freshwater amphipod invader from environmental differences. In Irish rivers, the introduced Gammarus pulex replaces the native Gammarus duebeni celticus. However, the River Lissan in Northern Ireland is dissected by a weir that has slowed the upstream invasion by G. pulex. This allowed us in 2000 to sample three contiguous 150-m reaches that were (1) G. pulex dominated; (2) mixed Gammarus spp.; and (3) G. duebeni celticus only. In 2003, we resampled these reaches and one additional of mixed Gammarus species and one with only G. duebeni celticus further upstream. In temperature, conductivity, and pH, there were statistically significant but no biologically relevant differences among the five reaches of 2003, and between the three reaches surveyed in both years. Although there was evidence of recovery in macroinvertebrate diversity and richness in invaded reaches between years, continued upstream invasion was associated with sustained reductions in these community metrics as compared to un-invaded sites. Community ordination indicated (1) different associations of community composition attributed to the distribution, abundance, and biomass of the invader; and (2) increasing similarity of invaded communities over time. The impact mechanisms of G. pulex on macroinvertebrate community composition may include predation and competition. The consequences of the observed community changes for ecosystem functioning require further investigation.

  • the replacement of a native freshwater amphipod by an invader roles for environmental degradation and intraguild predation
    Canadian Journal of Fisheries and Aquatic Sciences, 2004
    Co-Authors: Calum Macneil, Jaimie T. A. Dick, John Prenter, Mark Briffa, Nina J Fielding, Gillian E Riddell, Melanie J Hatcher, Alison M Dunn
    Abstract:

    We assessed the extent to which an invader, Gammarus pulex (Crustacea: Amphipoda), has replaced a native, Gammarus duebeni celticus, over a 13-year period in a European river system and some of the...

  • the functional role of Gammarus crustacea amphipoda shredders predators or both
    Hydrobiologia, 2002
    Co-Authors: David W Kelly, Jaimie T. A. Dick, Ian W Montgomery
    Abstract:

    Gammarus spp. are traditionally viewed under the functional feeding group (FFG) concept as herbivorous `shredders'. Although recent studies suggest that Gammarus should also be viewed as predators, this latter role remains contentious. Here, in a laboratory experiment, we objectively examine the balance between shredder and predator roles in a common freshwater species. Gammarus pulex preyed significantly on mayfly nymph, Baetis rhodani, in both the presence and absence of excess leaf material. There was no significant difference in predation where the alternative food, that is, leaf material, was present as compared to absent. Also, G. pulex shredded leaf material in the presence and absence of B. rhodani. However, shredding was significantly reduced where alternative food, that is, B. rhodani prey, was present as compared to absent. Further, G. pulex had a clear leaf species preference. Our results suggest that Gammarus function as both predators and shredders, with the balance of the two roles perhaps depending on food availability and quality. We discuss implications for the use of the FFG concept in assessing freshwater processes, and the role that Gammarus predation may play in structuring macroinvertebrate communities.

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