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At least 73 records · Page 4Linked to original sources
PubMed2003

Littoral microcrustacean (Cladocera and Copepoda) indicators of acidification in Canadian Shield lakes.

We identify littoral microcrustacean indicators of acidification in 2 surveys of Canadian Shield lakes conducted 10 years apart. We found a total of 90 cladoceran and copepod species with richness increasing severalfold from acidic to nonacidic lakes. The fauna of the nonacidic lakes differed between the surveys. The 1987 survey employed activity traps, and caught more littoral taxa than the more recent, net-haul-based survey. Similar faunas were identified in the acidified lakes in both surveys, and several good indicator species were identified. For example, Acanthocycops vernalis was restricted to lakes with pH < 6. Sinobosmina sp. was very common but only in lakes with pH > 4.8. Tropocyclops extensus, Mesocyclops edax, and Sida crystallina were commonly found but only at pH > 5, and Chydorus faviformis only at pH > 5.9. These indicators showed promise in gauging the early stages of recovery from acidification in 3 lakes that were included in both surveys.

Acid Rain↗
PubMed2002

Laboratory evaluation of Mesocyclops annulatus (Wierzejski, 1892) (Copepoda: Cyclopidea) as a predator of container-breeding mosquitoes in Argentina.

In laboratory bioassays we tested the predatory capacity of the copepod Mesocyclops annulatus on Aedes aegypti and Culex pipiens larvae. A single adult female of M. annulatus caused 51.6% and 52.3% mortality of 50 first instar larvae of Ae. aegypti and Cx. pipiens respectively, in a 72 h test period. When alternative food was added to the containers, mortality rates declined to 16% and 10.3% for Ae. aegypti and Cx. pipiens respectively. When 50 first instar larvae of each of the two mosquito species tested were placed together with a single adult female of M. annulatus, mortality rates were 75.5% for Ae. aegypti larvae and 23.5% for Cx. pipiens larvae in a three day test period. Different density of adult females of M. annulatus ranged from 5 to 25 females produced mortality rates of Ae. aegypti first instar larvae from 50% to 100% respectively. When a single adult female of M. annulatus was exposed to an increasing number of first-instar Ae. aegypti larvae ranging from 10 to 100, 100% mortality was recorded from 1 to 25 larvae, then mortality declined to 30% with 100 larvae. The average larvae killed per 24 h period by a single copepod were 29.

Aedes↗
PubMed2004

Evaluation of Mesocyclops annulatus (Copepoda: Cyclopoidea) as a control agent of Aedes aegypti (Diptera: Culicidae) in Argentina.

We evaluated the potential of Mesocyclops annulatus as a control agent of Aedes aegypti in La Plata city (Argentina). Mosquito larval survivorship due to predation by these copepods was estimated at weekly intervals during the oviposition period of A. aegypti. Mean weekly A. aegypti larval survivorship in cylindrical plastic containers (12 cm height and 11 cm diameter) with copepods was significantly lower than in control containers. Furthermore, weekly larval survival was negatively correlated with M. annulatus adult density, and approximately 23 adult copepods/container would be a threshold density over which the weekly mosquito larval survivorship approached zero. The copepods were able to persist in all containers during approximately 100 days (in three of them until the end of the experiment: 155 days) without the resource represented by A. aegypti larvae. The predation and persistence observed suggest that M. annulatus is a potential control agent to be considered in biological control programs.

Aedes↗
PubMed2003

Occurrence of Mesocyclops ogunnus Onabamiro, 1957 (Copepoda Cyclopoida) in water bodies of São Paulo State, identified as Mesocyclops kieferi Van de Velde, 1984.

The aim of this work is clarify the identification of Mesocyclops ogunnus that occur in several reservoirs in the State of São Paulo and that was previously identified as Mesocyclops kieferi. These two species are closely related species with very similar characteristics. The differential characteristics are presented and the distribution of both species in the world is discussed.

Animals↗
PubMed2004

Longitudinal distribution of Copepoda populations in the transition zone of Paranapanema River and Jurumirim Reservoir (São Paulo, Brazil) and interchange with two lateral lakes.

Longitudinal changes in composition, abundance, and distribution of copepods were studied at the transition zone of Paranapanema River-Jurumirim Reservoir (SP, Brazil). The interchange of biotic material between marginal lakes and the river system was also examined. Water samples were obtained from 6 stations along a stretch of 13 km of the Paranapanema River, from an upstream reach with high water velocity up to the river mouth into Jurumirim Reservoir. Two other sites in lateral lakes were also sampled. Nine copepod taxa were identified: 3 calanoids (Argyrodiaptomus furcatus Sars, Notodiaptomus iheringi Wright, and N. conifer Sars) and 6 cyclopoids (Eucyclops Claus, Microcyclops Claus, Mesocyclops longisetus Thiébaud, Thermocyclops decipiens Fischer, T. minutus Lowndes, and Paracyclops Claus). Harpacticoids were also collected. Calanoid and cyclopoid nauplii and copepodids, and harpacticoids were the most abundant organisms. In general, there was a longitudinal decrease in copepod abundance, whereas an increase was detected near the lakes. The abundance of most copepods was inversely correlated with current velocity and suspended solids. Higher abundance was observed in the river main course during the rainy season, during which there is a higher connectivity between the lakes and the main river. This promotes exportation of biologic material from marginal lakes to the river system, a biotic exchange reflecting the importance of marginal lakes to the river community structure.

Animals↗
PubMed2005

Taxonomy, ecology, and geographical distribution of the species of the genus Thermocyclops Kiefer, 1927 (Copepoda, Cyclopoida) in São Paulo State, Brazil, with description of a new species.

The taxonomy and ecology of the cyclopoid copepod genus Thermocyclops were studied. Samples were collected in 207 water bodies located in the 22 hydrographic basins of São Paulo State, Brazil, including large reservoirs, small and shallow lakes, and ponds and rivers. The genus Thermocyclops inhabits mainly water bodies within a limnetic region. Four species were found, of which one is new: Thermocyclops iguapensis, which occurred in the reservoirs of the Ribeira do Iguape and Paraíba do Sul basins. The description of the new species and the geographical distribution of all four species in São Paulo State are presented. Thermocyclops decipiens was the most frequent species, occurring in 71% of the water bodies within a limnetic region. This species is characteristic of eutrophic environments where it can occur in great abundance, whereas Thermocyclops minutus is characteristic in oligotrophic systems. Thermocyclops inversus and Thermocyclops iguapensis n. sp. were not common but can occur together with Thermocyclops decipiens.

Animals↗
PubMed2006

Spatial and temporal distribution in density and biomass of two Pseudodiaptomus species (Copepoda: Calanoida) in the Caeté river estuary (Amazon region--North of Brazil).

Spatial and temporal density and biomass distribution of the planktonic copepods Pseudodiaptomus richardi and P. acutus along a salinity gradient were investigated in the Caeté River Estuary (North-Brazil) in June and December, 1998 (dry season) and in February and May, 1999 (rainy season). Copepod biomass was estimated using regression parameters based on the relation of dry weight and body length (prosome) of adult organisms. The Caeté River Estuary was characterized by high spatial and temporal variations in salinity (0.8-37.2). Exponential length-weight relationships were observed for both Pseudodiaptomus species. Density and biomass values oscillated between 0.28-46.18 ind. m-3 and 0.0022-0.3507 mg DW. m-3 for P. richardi; and between 0.01-17.02 ind. m-3 and 0.0005-0.7181 mg DW. m-3 for P. acutus. The results showed that the contribution of P. richardi for the secondary production in the Caeté River Estuary is more important in the limnetic zone than in other zones where euhaline-polyhaline regimes were predominant. However, it was not possible to observe a clear pattern of spatial and temporal distribution for P. acutus.

Animals↗
PubMed2003

Infection of Sphyrion laevigatum (Copepoda: Sphyriidae) on Genypterus blacodes (Pisces: Ophidiidae) from the Falkland Islands, South Atlantic.

The degree of parasitism by the parasitic copepod Sphyrion laevigatum on kingclip Genypterus blacodes in the Falkland Islands was investigated. In a sample of 719 kingclip, ranging in size from 35 to 145 cm total length, the prevalence of infection was 49%. The number of parasites per fish ranged from 0 to 24, with only 2% of the sample having more than 5 parasites. There was a significant increase in mean abundance of parasites with increasing fish age and length (P < 0.01 and P < 0.05, respectively). In addition, there was a significant difference in the prevalence in 1 of 3 geographical areas for the largest size class.

Age Distribution↗
PubMed2004

Aspects of the ecology and natural history of Paraergasilus rylovi (Copepoda, Ergasilidae) parasitic in unionids of Finland.

The distribution of Paraergasilus rylovi in 17 populations of unionids was investigated. In 1 unionid population, the parasite was studied regarding host age, size, sex, and the reproductive period (occurrence of egg sacs). Results from pooled material from the years 1987--1989 and 1996 (southern Finland, 11 populations) indicated that Anodonta piscinalis (n = 1,359) is the main host (total mean prevalence 71% and intensity +/-SE of infection 16.4+/-0.6). Pseudanodonta complanata (n = 106) was infected occasionally (3% and 1.3+/-0.3), whereas Unio pictorum (n = 108) and U. tumidus (n = 17) were not infected. Results from 17 A. piscinalis populations showed that P. rylovi occurs in southern Finland but not in northern Finland. In A. piscinalis, the mean intensity of infection was higher in lake populations than in river populations. Both host age and length had a negative relationship with the intensity of P. rylovi infection. Host sex did not affect the intensity of infection. Egg sacs of P. rylovi were found from June to August. There was a tendency for higher intensities of infection in autumn. Infection by the digenean Rhipidocotyle fennica had no effect on the intensity of P. rylovi infection.

Analysis of Variance↗
PubMed2003

New records for Dinemoura ferox (Copepoda: Siphonostomatoida: Pandaridae) from Pacific sleeper sharks captured in waters off eastern Taiwan.

Four of the 27 Pacific sleeper sharks (Somniosus pacificus Bigelow and Schroeder) captured in the western North Pacific Ocean off eastern Taiwan between 19 March and 18 May 2002 hosted the parasitic copepod Dinemoura ferox (Krøyer, 1838) on their body surface including the fins. This report documents a new host record as well as a new ocean record for D. ferox, which until now has only been reported from the benthopelagic sharks, Somniosus microcephalus (Bloch and Schneider) and Centrophorus squamosus (Bonnaterre), occurring in the north Atlantic Ocean off Greenland and Iceland.

Animals↗
PubMed2004

Sarcotretes (Copepoda: Pennellidae) parasitizing myctophid fishes in the Southern Ocean: new information from seabird diet.

Copepods are common parasites of marine fishes, but little information is available on the biology of species that parasitize mesopelagic fishes in oceanic waters. In this study, we report the finding of large numbers of Sarcotretes spp. (n = 2340) in dietary samples of king penguins collected at Crozet and the Falklands Islands. Analysis of penguin food indicates that S. scopeli Jungersen parasitizes myctophid fishes, Protomyctophum tenisoni (Norman), in the southern Indian Ocean and P. choriodon Hulley in the southern Atlantic. It suggests that the much rarer S. eristaliformis (Brian) also parasitizes myctophids, but the host species of that copepod remains to be determined. The new data add significant information concerning the hosts and distribution of Sarcotretes spp. in the Southern Ocean and emphasize the usefulness of ichthyophagous predators in revealing valuable information on the biology of organisms that parasitize their prey.

Animals↗
PubMed2004

Muscular anatomy and aspects of the structure of the antennae of Anthosoma crassum (Dichelesthiidae: Siphonostomatoidae: Copepoda).

The muscular anatomy and fine structure of the antennae of adult Anthosoma crassum are described from specimens collected from jaws of shortfin makos. Casual observations of live parasites showed that embedded adult A. crassum can move toward or away from the host by shortening or lengthening the antennae, respectively. These movements were controlled by antennal retractor muscles. Microprotuberances located on the distal antennal segments may increase friction between these copepods and their hosts, thus strengthening parasite attachment.

Animals↗
PubMed2006

The occurrence of Lepeophtheirus salmonis and Caligus clemensi (Copepoda: Caligidae) on three-spine stickleback Gasterosteus aculeatus in coastal British Columbia.

Infections with sea lice species belonging to Lepeophtheirus and Caligus are reported from examinations of 1,309 three-spine sticklebacks collected in coastal British Columbia. Over 97% of the 19,960 Lepeophtheirus specimens and nearly 96% of the 2,340 Caligus specimens were in the copepodid and chalimus developmental stages. The parasites were identified as Lepeophtheirus salmonis and Caligus clemensi based on morphology of adult stages. Between 1,763 and 1,766 base pairs (bp) of 18S rDNA from adult specimens collected from sticklebacks and salmon differed from the GenBank L. salmonis reference sequence by a single bp and were distinct from those of 2 other Lepeophtheirus species. A 530-bp region of 18S rDNA from chalimus stages of Lepeophtheirus obtained from sticklebacks and salmon was identical to that of the L. salmonis reference sequence. The three-spine stickleback is a new host record for L. salmonis. The prevalence of L. salmonis was 83.6% and that of C. clemensi was 42.8%. The intensities of these infections were 18.3 and 4.2, respectively. There was no significant relationship between sea lice abundance and stickleback condition factor. Significant spatial and temporal variations both in abundance of sea lice and surface seawater salinities were measured. The abundance of both sea lice species was lowest in zones in which surface seawater salinity was also lowest. Sticklebacks appear to serve as temporary hosts, suggesting a role of this host in the epizootiology of L. salmonis. The stickleback may be a useful sentinel species with which to monitor spatial and temporal changes in the abundance of L. salmonis and C. clemensi.

Animals↗
PubMed2006

Host specificity of Lepeophtheirus crassus (Wilson and Bere) (Copepoda: Caligidae) parasitic on the marlin sucker Remora osteochir (Cuvier) in the Atlantic Ocean.

Three species of remoras--Remora brachyptera (Lowe), Remora osteochir (Cuvier), and Remora remora (Linnaeus)--were collected from 4 species of billfishes--Istiophorus platypterus (Shaw), Makaira nigricans Lacepéde, Tetrapturus albidus Poey, and Tetrapturus pfluegeri Robins and de Sylva--on board a Japanese long-liner Shoyo Maru during her cruise in 2002 across the Atlantic. However, only the marlin sucker (R. osteochir) was found to carry a parasitic copepod, Lepeophtheirus crassus (Wilson and Bere, 1936). Although 12 species of parasitic copepods have been reported from billfishes around the world ocean, none of them is L. crassus. Thus, L. crassus is considered a parasite specific to the marlin sucker.

Animals↗
PubMed2003

A new species of parastenhelia (Copepoda: Harpacticoida: Parastenheliidae) from Korea.

A new species belonging to the genus Parastenhelia of family Parastenheliidae is described on the basis of the specimens of both sexes collected from the zosteran bed at Seungbong Island and from the shallow sandy bottoms of Jeju Island in Korea. It is distinguished from the congeners by its character combination of inserted location and the length proportion of the inner seta on the first endopodal segment of leg 1, shape of female leg 5, the modified male legs 2-3 endopods, and the number of setae on male leg 5 exopod. An emended table of morphological characters for the genus is provided.

Animals↗
PubMed2003

A marine harpacticoid, Quinquelaophonte koreana sp. nov. from a sandy beach in Korea (Crustacea: Copepoda).

A new interstitial copepod of the family Laophontidae was found in the samples from a sandy beach at Taean, west coast of Korea. This species was described and named as Quinquelaophonte koreana sp. nov. Present new species is clearly distinguishable from its congeners with the combined characters of the short caudal ramus and its short ornamented seta V, two setae on the antennary exopod, and small rounded rostrum. Q. koreana sp. nov. is the first record of Quinquelaophonte from the Northeast Asian coast.

Animals↗
PubMed2005

A new species of the genus Attheyella (Copepoda: Harpacticoida: Canthocamptidae) from Gosu cave in Korea.

A new species, Attheyella namkungi sp. nov., is described from Gosu cave at Danyang, Chungcheongbuk-do, South Korea. This species bears a superficial resemblance to A. coreana Miura, 1969 in having a 2-segmented mandibular palp with only four smooth apical setae, and in the armature formulae of the antennary exopod and thoracic legs. However the new species is clearly distinguishable by the non-sexually dimorphic caudal rami, two long plumose setae and a short seta on leg 6, and the absence of the setular row at the inner lateral margin of each caudal ramus. The new species is characterized from other congeners by having two adjacent inner spines on female leg 3 endopod-2, the caudal ramus twice as long as its width, absence of a barbed apophysis on male leg 3 endopod-2, and the seta number of legs 5 and 6. A key to the Korean species of the genus Attheyella is provided.

Animal Structures↗
PubMed2005

Two new species of ochridacyclops (Kiefer, 1937) (Copepoda, Cyclopoida) from Kenya and Nepal.

Two species of cyclopoid copepods, Ochridacyclops kenyaensis sp. nov. and O. nepalensis sp. nov. are described as the first records of this genus from Kenya and Nepal, respectively. Ochridacyclops kenyaensis can easily be distinguished from its congeners by having a rounded and blunt distal end of the outer terminal seta (IV) on the caudal rami, and by the inner terminal spine being about equal in length to the outer terminal spine on the endopod of leg 4. Ochridacyclops nepalensis can easily be distinguished from other members of the genus by having two spines on exopodal segment 3 of leg 1, and by the proportions of the caudal rami, which are 3.4 times longer than wide.

Anatomy, Comparative↗