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1.
Zootaxa ; 4612(2): zootaxa.4612.2.7, 2019 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-31717069

RESUMEN

The Family Entomolepididae is composed by 7 genera and 15 species. During a survey on the known species and the search for new species, a new Spongiopsyllus is described associated with sponge Aplysina insularis. The new species has antennule 14-segmented, four setae on both lobes of maxillule, some unique features on the leg setation and the armature of the maxilliped. These characteristics make the new species different from all other congeners in Spongiopsyllus. The diagnosis of Entomopsyllus was also revised once it does not consider the differences to Spongiopsyllus which was created posteriorly to its erection. An analysis of Entomopsyllus stocki also indicated that leg 5 somite and the genital somite are fused, instead of separated as originally stated, the structure is also redescribed. Finally, Parmulodes verrucosus is studied and an up-to-date description is provided, correcting some inconsistencies in the armature formula of the antennule and the leg setation, and providing re-analysis of the other appendages.


Asunto(s)
Copépodos , Poríferos , Animales , Genitales
2.
Syst Parasitol ; 96(9): 799-804, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31721054

RESUMEN

Kabata separated species of Pseudocharopinus Kabata, 1964 and Charopinus Krøyer, 1863 in 1964 based mainly on four characteristics. Currently Pseudocharopinus has 11 species while Charopinus consists of three species considered valid. Pseudocharopinus malleus (Rudolphi in Nordmann, 1832) and Charopinus dubius T. Scott, 1900 were collected and studied from hosts off South Africa. Additional to previous reports from South African waters, P. malleus is reported from Torpedo sinuspersici Olfers and T. fuscomaculata Peters while C. dubius is reported from Leucoraja wallacei (Hulley) and Rajella dissimilis (Hulley), all new host records. In an attempt to estimate the evolutionary relationships among Pseudocharopinus spp. a cladistic analysis was performed by means of parsimony using described and illustrated features of the adult females. Due to the mostly unresolved 50% majority rule tree, a key for the identification of the adult females of Pseudocharopinus spp. is compiled. Additionally, a key for the identification of adult females of Charopinus spp. is provided.


Asunto(s)
Clasificación , Copépodos/clasificación , Filogenia , /parasitología , Animales , Copépodos/anatomía & histología , Femenino , Especificidad de la Especie
3.
Biol Bull ; 237(2): 170-179, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31714852

RESUMEN

Post-embryonic diapause in copepods is an adaptation that allows species in the copepod family Calanidae to thrive in high-latitude environments by transforming a short spring phytoplankton bloom into large numbers of lipid-rich individuals capable of surviving a long period of starvation. The copepods, with their high-energy lipid reservoirs, are a critical food source for higher trophic levels, making the Calanidae a key component of high-latitude marine ecosystems. The physiological ecology of the developmental program remains poorly understood. However, new studies using high-throughput RNA sequencing approaches are giving detailed access to physiological status by generating gene expression profiles for both field-collected and laboratory-incubated individuals. These are beginning to characterize the diapause phenotype, elucidate the transcriptional and physiological progression through the diapause program, and illustrate the effects of organism-environment interactions. This paper reviews gene expression profiling studies on the life cycle and diapause program of Neocalanus flemingeri Miller (1988) that were conducted as part of a long-term observation program in the northern Gulf of Alaska. It summarizes recent findings and relates them to the ecology of this species and to that of other calanids.


Asunto(s)
Copépodos , Diapausa , Animales , Ecosistema , Fitoplancton , Transcriptoma
4.
Biol Bull ; 237(2): 76-89, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31714854

RESUMEN

Diapause at depth is considered an integral part of the life cycle of Calanus copepods, but few studies have focused on the Arctic species Calanus glacialis and Calanus hyperboreus. By analyzing a large set of pan-arctic observational data compiled from multiple sources, we show that Arctic Calanus has a broad depth distribution in winter, indicating that diapause at depth is a facultative strategy. Both species' vertical distributions tend to deepen in winter and to be deeper and broader with increasing bottom depth, while individuals are aggregated closer to the sea floor in shallow areas. These results indicate that Arctic Calanus species pursue a relatively deep diapause habitat but are topographically blocked on the shelves. Interspecific differences in depth distribution during diapause suggest the importance of predation. The larger C. hyperboreus has a deeper diapause depth than C. glacialis, potentially to alleviate predation pressure or as a result of predation loss near the surface. Moreover, the mean depth of C. hyperboreus in winter is negatively associated with latitude, indicating a shoaling of the diapause population in the central Arctic Ocean where predation pressure is lower. Our results suggest a complex diapause behavior by Arctic Calanus, with implications for our view of the species' roles in Arctic ecosystems.


Asunto(s)
Copépodos , Diapausa , Animales , Regiones Árticas , Ecosistema , Estaciones del Año
5.
Biol Bull ; 237(2): 90-110, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31714858

RESUMEN

Calanus finmarchicus and Calanus glacialis are keystone zooplankton species in North Atlantic and Arctic marine ecosystems because they form a link in the trophic transfer of nutritious lipids from phytoplankton to predators on higher trophic levels. These calanoid copepods spend several months of the year in deep waters in a dormant state called diapause, after which they emerge in surface waters to feed and reproduce during the spring phytoplankton bloom. Disruption of diapause timing could have dramatic consequences for marine ecosystems. In the present study, Calanus C5 copepodites were collected in a Norwegian fjord during diapause and were subsequently experimentally exposed to the water-soluble fraction of a naphthenic North Sea crude oil during diapause termination. The copepods were sampled repeatedly while progressing toward adulthood and were analyzed for utilization of lipid stores and for differential expression of genes involved in lipid metabolism. Our results indicate that water-soluble fraction exposure led to a temporary pause in lipid catabolism, suggested by (i) slower utilization of lipid stores in water-soluble fraction-exposed C5 copepodites and (ii) more genes in the ß-oxidation pathway being downregulated in water-soluble fraction-exposed C5 copepodites than in the control C5 copepodites. Because lipid content and/or composition may be an important trigger for termination of diapause, our results imply that the timing of diapause termination and subsequent migration to the surface may be delayed if copepods are exposed to oil pollution during diapause or diapause termination. This delay could have detrimental effects on ecosystem dynamics.


Asunto(s)
Copépodos , Diapausa , Petróleo , Animales , Regiones Árticas , Ecosistema , Metabolismo de los Lípidos
6.
Biol Bull ; 237(2): 145-169, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31714859

RESUMEN

Long-lasting embryonic dormancy in invertebrates defies our understanding of what constitutes life because, for example, eggs of some copepods can delay hatching for decades or even centuries. Copepods, often millimeter-sized crustaceans, are some of the most numerous multicellular organisms on earth and are key organisms in most aquatic food webs. Some important free-living marine and estuarine species overwinter or oversummer by arrested embryogenesis in dormancy. The present contribution discusses the complex mechanisms behind embryonic dormancy by compiling knowledge from the 42 calanoid copepods from the superfamily Centropagoidea with well-described embryonic dormancy, which has been of scientific interest for decades. However, the determination of categories of copepod resting eggs-that is, diapause and quiescence, transitions between categories, the mechanisms controlling arrested development by the embryos, and how they interact with their surroundings-is not fully understood. Moreover, a clear link between the presence of the free-swimming population and their resting eggs in sediments is still not convincingly demonstrated. Here I evaluate the relative significance of potential cues driving the production of and the phase shift between egg categories. Understanding the initiation and termination of embryonic dormancy is of great importance for fundamental science-that is, population and food web ecology as well as climate science, aquaculture live feed, and ballast water research. Molecular techniques are developing rapidly, especially within health sciences, thus providing relevant tools applicable for plankton research. Here I suggest that applying molecular methods in addition to traditional physiological approaches in future research will lead to greater understanding of copepod embryonic dormancy, one of nature's wonders.


Asunto(s)
Copépodos , Animales , Acuicultura , Desarrollo Embrionario , Cadena Alimentaria , Óvulo
7.
Zootaxa ; 4579(1): zootaxa.4579.1.1, 2019 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-31715705

RESUMEN

A large collection of mesoparasitic copepods from polychaete hosts collected in northern European waters was examined. The term mesoparasitic refers to highly transformed copepods where the adult female attaches by embedding part of its body in the host. Representatives of five known familes were found and a new family is established. A single new species, Bradophila minuta sp. nov., was described in the family Bradophilidae. It occurred exclusively on the flabelligerid Diplocirus glaucus (Malmgren, 1867). Two genera of the family Herpyllobiidae were represented: Herpyllobius Steenstrup Lütken, 1861 and Eurysilenium M. Sars, 1870. Herpyllobius arcticus Steenstrup Lütken, 1861 was found on at least five different polynoid hosts, two of which, Harmothoe fragilis Moore, 1910 and Antinoe sp., were new host records. A new species, H. cluthensis sp. nov. was described from Malmgrenia species in Scottish waters. The large species, Herpyllobius cordiformis Lützen, 1964, was collected in Arctic waters from Eunoe cf. oerstedi. It is the first report of this parasite in Europe. The common parasite H. polynoes (Krøyer, 1864) was found on six different polynoid hosts, three of which, Harmothoe bifera, Malmgreniella mcintoshi Tebble Chambers, 1982 and Eunoe ?barbata are new host records. Eurysilenium truncatum M. Sars, 1870 was collected from Eucranta villosa Malmgren, 1866, Eunone sp., and Gattyana cirrhosa (Pallas, 1766). The material from Eucranta villosa caught at 72.6ºN comprises both a new host record and is the most northerly report of this parasite. Specimens of Eurysilenium which differed from E. truncatum in a number of features were found on Harmothoe fragilis and H. impar (Johnston, 1839). A new family, the Pholoicolidae, is established to accommodate Pholicola chambersae gen. et sp. nov., parasitic on Pholoe pallida Chambers, 1985. The family Phyllodicolidae was represented by all three of its known species: Phyllodicola petiti (Delamare Deboutteville Laubier, 1960), Cyclorhiza eteonicola Heegaard, 1942 and C. megalova Gotto Leahy, 1988. The former was found on Eumida ockelmanni Eibye-Jacobsen, 1987, a new host record. A single ovigerous female of C. eteonicola was collected from a new host, Eteone spetsbergensis Malmgren, 1865. Cyclorhiza megalova was common on Eteone longa (Fabricius, 1780) and E. longa/flava complex. A rich diversity of members of the family Saccopsidae was found, including three known species of Melinnacheres M. Sars, 1870 plus nine new species placed in four new genera. Melinnacheres was represented by M. ergasiloides M. Sars, 1870, M. steenstrupi Bresciani Lützen, 1961 and M. terebellidis Levinsen, 1878. Melinnacheres ergasiloides was found on Melinna elizabethae McIntosh, 1914, M. steenstrupi on members of the Terebellides stroemi-complex and T. atlantis Williams, 1984, while M. terebellidis was found on the T. stroemi-complex and on T. shetlandica Parapar, Moreira O'Reilly, 2016. A new genus, Trichobranchicola gen. nov., was established to accommodate T. antennatus gen. et sp. nov., a parasite of Trichobranchus sikorskii Leontovich Jirkov in Jirkov, 2001, T. glacialis Malmgren, 1866 and Trichobranchus sp. The second new genus, Lanassicola gen. nov., was established to accommodate the type species, Lanassicola arcticus gen. et sp. nov. parasitic on Lanassa venusta (Malm, 1874), plus two additional species, L. bilobatus gen. et sp. nov. on Lanassa nordenskjoeldi Malmgren, 1866, and L. dorsilobatus gen. et sp. nov. on Proclea graffii (Langerhans, 1884). A new subfamily, Euchonicolinae, was established within the Saccopsidae to accommodate two new genera, Euchonicola gen. nov. and Euchonicoloides gen. nov. The type species of Euchonicola gen. nov. is E. caudatus gen. et sp. nov., a parasite of Euchone sp., and it includes two other species, E. linearis gen. et sp. nov. on Chone sp., and E. parvus gen. et sp. nov. on Euchone sp. The type species of Euchonicoloides gen. nov. is E. elongatus gen. et sp. nov. found on a host belonging to the genus Euchone, and it also includes Euchonicoloides halli gen. et sp. nov. from Jasmineira caudata Langerhans, 1880. Four species of the family Xenocoelomidae were found: Xenocoeloma alleni (Brumpt, 1897), X. brumpti Caullery Mesnil, 1915, X. orbicularis sp. nov. and Aphanodomus terebellae (Levinsen, 1878). Xenocoeloma alleni was found on four different species of Polycirrus and on Amaeana trilobata (M. Sars, 1863) and X. brumpti was found on Polycirrus norvegicus Wollebaek, 1912. Xenocoeloma orbicularis sp. nov. occurred only on Paramphitrite birulai (Ssolowiew, 1899). Aphanodomus terebellae was found on three hosts, only one of which, Leaena abranchiata was new.


Asunto(s)
Copépodos , Poliquetos , Animales , Europa (Continente) , Femenino , Océanos y Mares
8.
Zootaxa ; 4565(3): zootaxa.4565.3.3, 2019 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-31716463

RESUMEN

Azygokeras columbiae from Bute Inlet, British Columbia, Canada, is re-described, correcting some details and adding information not available in the original description. Azygokeras columbiae is unique amongst male Aetideidae in having the right antennule modified for grasping but without a true knee joint (geniculation) between segments XX and XXI nor a hiatus in the musculature at this joint, typical of taxa with a geniculate male antennule. Male Azygokeras have wide pivot points and arthrodial membranes between segments XXI and XXII, XXIII and XXIV and XXV and XXVI that allow greater movement in several planes than in homologous segments of Euaugaptilus and Heterorhabdus. Modifications of the terminal antennular joints allow for extensive movement in several planes associated with a series of short muscles in segments XIX to XXVI. These muscles become progressively more massive from proximal to distal on the antennule and are paired with an antagonistic muscle also increasing in mass distally.


Asunto(s)
Copépodos , Animales , Colombia Británica , Masculino , Movimiento , Músculos
9.
Zootaxa ; 4652(1): zootaxa.4652.1.7, 2019 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-31716887

RESUMEN

Two new species of the genus Panaietis (Copepoda: Cyclopoida: Anthessiidae) inhabiting the inside of the mouth cavities of marine snails are described from shallow waters of southern Japan. Panaietis bobocephala sp. nov. collected from the small abalone, Haliotis asinina (Vetigastropoda: Lepetellida: Haliotidae), is mainly characterized by the well-developed posterolateral corners of tergite on first pediger, the pointed spines on legs 1 to 5, the maxilla with two teeth, and the leg armature formula. Panaietis flavellata sp. nov. from Angaria neglecta (Vetigastropoda: Trochida: Angariidae) is characterized by the combination of following: leg 5 is situated on ventral side of the fifth pediger, inner margin of the second segment of antenna greatly protruded, and the leg armature formula.


Asunto(s)
Copépodos , Gastrópodos , Animales , Japón
10.
Zootaxa ; 4612(4): zootaxa.4612.4.2, 2019 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-31717038

RESUMEN

The article presents a review of the literature on known representatives of the genus Lecanophryella containing general characteristics of the members of this genus, information on morphology and data on distribution. Diagnostic characters of L. satyanandani is emended based on material collected from a new locality. A new species, Lecanophryella indica as epibiont on the body surface of cyclopoid copepod from the Zuari estuary, west coast of India is also described.


Asunto(s)
Cilióforos , Copépodos , Animales , India
11.
Syst Parasitol ; 96(9): 777-788, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31654292

RESUMEN

A new species of parasitic copepod, Echthrogaleus spinulus n. sp. (Pandaridae), is described from the torpedo ray Tetronarce tokionis (Tanaka) (Torpedinidae) captured in pelagic Hawaiian waters. The new species has pediger 4 bearing large dorsal plates with denticles on posterior margin, genital complex with posterolateral lobes widely curved medially and overlapping, leg 4 exopod incompletely 3-segmented, and the largest body size (maximum length 16 mm from anterior rim of frontal plates to tip of caudal rami, excluding setae). This morphology does not match any of the seven valid species of Echthrogaleus Steenstrup & Lütken, 1861. Analysis of 28S rDNA sequences separated the new material from the Central Pacific from samples of E. coleoptratus in the Atlantic and Eastern Pacific Oceans. However, due to the lack of DNA sequences in the databases, the new 28S rDNA sequence cannot used to confirm the species identity. The unique morphological characteristics of the Central Pacific female copepods combined with 28S rDNA sequencing was used as a basis to validate the new species.


Asunto(s)
Copépodos/clasificación , Torpedo/parasitología , Animales , Copépodos/anatomía & histología , Copépodos/genética , Femenino , Hawaii , Océano Pacífico , ARN Ribosómico 28S/efectos de los fármacos , ARN Ribosómico 28S/genética , Especificidad de la Especie
12.
Environ Pollut ; 255(Pt 1): 113189, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31542673

RESUMEN

A growing concern for contamination due to pharmaceutical compounds in groundwater is expanding globally. The ß-blocker propranolol is a ß-adrenoceptors antagonist commonly detected in European groundwater bodies. The effect of propranolol on stygobiotic species (obligate groundwater dweller species) is compelling in the framework of environmental risk assessment (ERA) of groundwater ecosystems. In fact, in Europe, ERA procedures for pharmaceuticals in groundwater are based on data obtained with surrogate surface water species. The use of surrogates has aroused some concern in the scientific arena since the first ERA guideline for groundwater was issued. We performed an ecotoxicological and a behavioural experiment with the stygobiotic crustacean species Diacyclops belgicus (Copepopda) to estimate a realistic value of the Predicted No Effect Concentration (PNEC) of propranolol for groundwater ecosystems and we compared this value with the PNEC estimated based on EU ERA procedures. The results of this study showed that i) presently, propranolol does not pose a risk to groundwater bodies in Europe at the concentrations shown in this study and ii) the PNEC of propranolol estimated through the EU ERA procedures is very conservative and allows to adequately protect these delicate ecosystems and their dwelling fauna. The methodological approach and the results of this study represent a first contribution to the improvement of ERA of groundwater ecosystems.


Asunto(s)
Antagonistas Adrenérgicos beta/análisis , Monitoreo del Ambiente/métodos , Agua Subterránea/química , Propranolol/análisis , Contaminantes Químicos del Agua/análisis , Animales , Copépodos/efectos de los fármacos , Ecosistema , Ecotoxicología , Europa (Continente) , Preparaciones Farmacéuticas/análisis , Propranolol/toxicidad , Medición de Riesgo/métodos
13.
Biol Lett ; 15(9): 20190495, 2019 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-31506036

RESUMEN

Compared with uninfected individuals, infected animals can exhibit altered phenotypes. The changes often appear beneficial to parasites, leading to the notion that modified host phenotypes are extended parasite phenotypes, shaped by parasite genes. However, the phenotype of a parasitized individual may reflect parasitic manipulation, host responses to infection or both, and disentangling the contribution of parasite genes versus host genes to these altered phenotypes is challenging. Using a tapeworm (Schistocephalus solidus) infecting its copepod first intermediate host, I performed a full-factorial, cross-infection experiment with five host and five parasite genotypes. I found that a behavioural trait modified by infection, copepod activity, was affected by both host and parasite genotype. There was no clear evidence for host genotype by parasite genotype interactions. Several observations indicated that host behaviour was chiefly determined by parasite genes: (i) all infected copepods, regardless of host or parasite genotype, exhibited behavioural changes, (ii) parasitism reduced the differences among copepod genotypes, and (iii) within infected copepods, parasite genotype had twice as large an effect on behaviour as host genotype. I conclude that the altered behaviour of infected copepods primarily represents an extended parasite phenotype, and I discuss how genetic variation in parasitic host manipulation could be maintained.


Asunto(s)
Cestodos , Copépodos , Parásitos , Animales , Genotipo , Interacciones Huésped-Parásitos
14.
Syst Parasitol ; 96(8): 715-722, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31515681

RESUMEN

A new species of Dermoergasilus Ho & Do, 1982 (Copepoda: Ergasilidae) parasitic on the gills of the redbelly tilapia Coptodon zillii (Gervais) from Basrah, southern Iraq, is described. Dermoergasilus cichlidus n. sp. is morphologically similar to D. longiabdominalis El-Rashidy & Boxshall, 2001 in the body length to width ratio, the swimming legs armature, the shape of the urosome and the small slightly spiniform seta on the exopodal segment of leg 5. However, the main differences are the presence of long setae on the endopod of leg 1 in D. cichlidus n. sp. (vs relatively short setae); the inner apical spine on the tip of the endopod of leg 1 being only slightly longer than the outer apical spine (vs inner apical spine about twice as long as the outer); the first interpodal sternite ornamented with spinules (vs interpodal sternites not ornamented); and the caudal rami and anal somite of equal length (vs caudal rami length c.2/3 of the length of the anal somite). Dermoergasilus occidentalis can be distinguished from D. cichlidus n. sp. by the relative length of the antennal segments, the absence of a minute terminal spine on the digital process of the caudal ramus and by differences in the mouth parts.


Asunto(s)
Copépodos/clasificación , Copépodos/fisiología , Tilapia/parasitología , Animales , Copépodos/anatomía & histología , Branquias/parasitología , Irak , Especificidad de la Especie
15.
Appl Opt ; 58(26): 7022-7027, 2019 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-31503970

RESUMEN

We present autofluorescence of six zooplankton species, including salmon lice (Lepeophtheirus salmonis), for the purpose of classification in marine environments. Using a 410 nm excitation wavelength, we find that all measured zooplankton species exhibit broad cyan fluorescence centered around 510-520 nm. Furthermore, salmon lice show an absence of red fluorescence from undigested chlorophyll, which is measured from the gut of the herbivorous zooplankton species. We show the capability to distinguish noneating species, including salmon lice, from algae-eating species using a dual-band analysis of the fluorescence spectra. This shows the potential of autofluorescence as an important signature in real-time monitoring and classification of salmon lice.


Asunto(s)
Copépodos/clasificación , Zooplancton/fisiología , Animales , Larva/fisiología , Espectrometría de Fluorescencia
16.
Syst Parasitol ; 96(7): 603-616, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31372880

RESUMEN

Lepeophtheirus lichiae Barnard, 1948 (Copepoda: Caligidae), a very rare and poorly known sea louse, is redescribed based on a single newly collected female. The specimen was collected from the dorsal body surface of the leerfish, Lichia amia (Linnaeus) caught in north-eastern Mediterranean waters off the Turkish coast. The original and only available description of L. lichiae was incomplete and with only three illustrations: the dorsal view of the female habitus, the sternal furca, and the postantennal process. Here, we present a full re-description of female of L. lichiae and report it from the Mediterranean Sea for the first time.


Asunto(s)
Copépodos/clasificación , Copépodos/fisiología , Perciformes/parasitología , Animales , Copépodos/citología , Femenino , Mar Mediterráneo , Especificidad de la Especie
17.
Glob Chang Biol ; 25(12): 4147-4164, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31449341

RESUMEN

Differences in population vulnerability to warming are defined by spatial patterns in thermal adaptation. These patterns may be driven by natural selection over spatial environmental gradients, but can also be shaped by gene flow, especially in marine taxa with high dispersal potential. Understanding and predicting organismal responses to warming requires disentangling the opposing effects of selection and gene flow. We begin by documenting genetic divergence of thermal tolerance and developmental phenotypic plasticity. Ten populations of the widespread copepod Acartia tonsa were collected from sites across a large thermal gradient, ranging from the Florida Keys to Northern New Brunswick, Canada (spanning over 20° latitude). Thermal performance curves (TPCs) from common garden experiments revealed local adaptation at the sampling range extremes, with thermal tolerance increasing at low latitudes and decreasing at high latitudes. The opposite pattern was observed in phenotypic plasticity, which was strongest at high latitudes. No relationship was observed between phenotypic plasticity and environmental variables. Instead, the results are consistent with the hypothesis of a trade-off between thermal tolerance and the strength of phenotypic plasticity. Over a large portion of the sampled range, however, we observed a remarkable lack of differentiation of TPCs. To examine whether this lack of divergence is the result of selection for a generalist performance curve or constraint by gene flow, we analyzed cytochrome oxidase I mtDNA sequences, which revealed four distinct genetic clades, abundant genetic diversity, and widely distributed haplotypes. Strong divergence in thermal performance within genetic clades, however, suggests that the pace of thermal adaptation can be relatively rapid. The combined insight from the laboratory physiological experiments and genetic data indicate that gene flow constrains differentiation of TPCs. This balance between gene flow and selection has implications for patterns of vulnerability to warming. Taking both genetic differentiation and phenotypic plasticity into account, our results suggest that local adaptation does not increase vulnerability to warming, and that low-latitude populations in general may be more vulnerable to predicted temperature change over the next century.


Asunto(s)
Copépodos , Adaptación Fisiológica , Animales , Canadá , Florida , Genética de Población , Temperatura Ambiental
18.
Mar Pollut Bull ; 146: 145-154, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31426142

RESUMEN

Zooplankton were studied in the largest scale investigation in the South Yellow Sea in spring 2007 by using large plankton net when the green tide hasn't yet occurred. Ninety-six zooplankton species were identified. Copepods, pelagic larvae and hydromedusae were comprised of the largest number of species; Calanus sinicus, Paracalanus parvus, Aidanosagitta crassa, Euphausiidae larvae, Oithona plumifera and Corycaeus affinis were dominant species and their abundance comprised 81.65% of total abundance. Three high abundance areas contained with an average of 224.31 ±â€¯247.93 individual/m3, with an average total biomass of 674.33 ±â€¯1696.92 mg/m3; The average of Shannon-Wiener diversity, Pielou evenness and Margalef richness was 1.96 ±â€¯0.61, 0.50 ±â€¯0.14 and 2.31 ±â€¯0.95, respectively. The Shannon-Wiener diversity and Pielou evenness showed positive correlation with bottom temperature, while Shannon-Wiener diversity and Margalef richness were positively correlated with bottom salinity. Additionally, Pielou evenness and Margalef richness showed negative correlation with total abundance which indicated that sampling efforts might affect the findings.


Asunto(s)
Zooplancton , Animales , Biomasa , China , Copépodos , Monitoreo del Ambiente/métodos , Océanos y Mares , Densidad de Población , Salinidad , Estaciones del Año , Temperatura Ambiental
19.
Mar Pollut Bull ; 149: 110492, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31437615

RESUMEN

Marine antifouling paints (MAPs) are widely used to prevent organisms from fouling vessel hulls. When scraped from vessels as part of regular maintenance, MAP particles discharged into the seawater become a source of toxic substances, like copper (Cu), to the environment, and biocides leaching from them are known to cause toxic effects on non-target organisms. We investigated the toxicity of MAP particles collected from a Bermuda boatyard on local copepod communities using two experiments. Copepod survival, Chlorophyll a and total dissolved Cu concentrations were measured before and after MAP particles addition. In an acute toxicity test, the addition of 0.3 g/L of MAP particles resulted in 0% copepods survival within 88 h and increased dissolved Cu by 1.8 µM. A significant inverse relationship was observed between copepod survival and MAP particles quantity, highlighting the toxic effects of MAP particles from boat maintenance on copepod communities in the surrounding seawater.


Asunto(s)
Copépodos , Cobre , Desinfectantes , Animales , Bermudas , Clorofila A , Copépodos/efectos de los fármacos , Cobre/farmacología , Cobre/toxicidad , Desinfectantes/farmacología , Desinfectantes/toxicidad , Pintura , Agua de Mar , Navíos , Pruebas de Toxicidad Aguda , Contaminantes Químicos del Agua/análisis
20.
Environ Sci Pollut Res Int ; 26(29): 30279-30285, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31432368

RESUMEN

Zooplankton biomass and water environment factors in Xiaoxingkai Lake were investigated, and the correlation between biomass and water environment factors was performed using the Pearson correlation analysis and redundancy analysis (RDA). The results showed that the highest zooplankton biomass was recorded in summer and the lowest in spring. Water depth, transparency (SD), electric conductivity, and total nitrogen were the highest in spring, while temperature and total phosphorus were the highest in summer. The values of pH and turbidity were the highest in autumn, while chloride ion and chlorophyll a were the highest in winter. During the spring period, Protozoa were positively correlated with conductivity, transparency (SD), and total nitrogen. While Rotifera demonstrated a strong correlation with turbidity, pH, temperature, and total phosphorus in summer and autumn seasons, and Cladocera were correlated with water depth. There were negative correlations of chlorophyll a and chlorine on Copepoda during the winter. RDA results displayed that zooplankton had strong relationships with the physicochemical characteristics in Xiaoxingkai Lake.


Asunto(s)
Monitoreo del Ambiente/métodos , Lagos/química , Zooplancton/crecimiento & desarrollo , Animales , Biomasa , China , Clorofila A/metabolismo , Cladóceros/crecimiento & desarrollo , Cladóceros/metabolismo , Copépodos/crecimiento & desarrollo , Copépodos/metabolismo , Nitrógeno/análisis , Fósforo/análisis , Rotíferos/crecimiento & desarrollo , Rotíferos/metabolismo , Estaciones del Año , Temperatura Ambiental , Zooplancton/metabolismo
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