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1.
Cladocera and Copepoda fauna, from ten lakes in the Alta water-course,northern Norway, have been collected and investigated. A totalof 42 species (34 Cladocera and 8 Copepoda) were recorded. Thenumber of Cladoceran species is high when compared with thatregistered for other areas of similar latitude, and Cladoceranspecies abundance is also greater than that reported for otherregions of northern and central Scandinavia. In addition, themean number of planktonic species present at any given timein the lakes (4.9 Cladocera and 3.4 Copepoda) was comparativelyhigh. Eight species have never been recorded as existing farthernorth than the Alta water-course, Three other species have beenrecorded at higher latitudes in North America, but not in Eurasia.Several species, of which there are only a few published records,arc rare in northern Scandinavia, and nine species were notconsidered by Illies (1978), as existing in the region of thepresent study.  相似文献   

2.
A synthesis of current knowledge of the Cladocera living in non-surface waters is provided. For all 94 species and subspecies recorded (Dec. 1994) we give information on their ranges, ecological characteristics, and a review of literature data. We also give a historic survey of the development of concepts, identify categories among groundwater-dwelling species, and discuss their adaptations and the evolutionary lines present. Of the estimated total of c. 450 non-marine Cladocera of the world, c. 20% may occur in underground aquatic habitats, but true groundwater forms (stygobionts or stygobites) are relatively few, possibly not more than 10 species (c. 2.5% of the total). This number may increase, as attention is given to subterranean habitats outside Europe.  相似文献   

3.
Report on a collection of cladocera and copepoda from Nepal   总被引:11,自引:11,他引:0  
22 species of Cladocera and 14 species of Copepoda are reported, mainly from Kathmandu valley, Central Nepal and some from high-altitude lakes in the Khumbu area, East Nepal. Two species are new to science; neither can, however, be named due to inadequate material. The relation between Macrothrix laticornis (Jurine, 1820), M. spinosa King, 1853 and M. goeldii Richard, 1897 is discussed; M. goeldii is set as synonym to M. spinosa; new morphological criteria, permetting a separation to M. laticornis and M. spinosa, are given. Some biogeographical aspects of the fauna encountered are: 1) among Copepoda two calanoïds of oriental origin and one of supposed palaearctic origin reach Kathmandu valley; all other Copepoda are circumtropical or cosmopolite species; no oriental Cyclopoïda were found; 2) at higher altitudes, no Cyclopoïda were found, and the Calanoïda were endemic species of the palaearctic genus Arctodiaptomus; 3) no oriental Cladocera were found in Kathmandu valley; the majority of species were cosmopolitan, the remainder circumtropical; 4) at high altitudes, endemic species of palaearctic genera exist next to a set of cosmopolitans.Contribution no 21 from the Netherlands Centre for Alpine Biological Research  相似文献   

4.
A checklist of the Cladocera of Israel and Eastern Sinai   总被引:2,自引:2,他引:0  
Sixty species of Cladocera are recorded from Israel and Eastern Sinai after the examination of several collections, and include 18 new records for the area as well as 9 species known only from the literature. Chydoridae dominate the fauna, with 27 species recorded, followed by Daphniidae with 21 species.  相似文献   

5.
This is the very first checklist of the terrestrial gastropods of Nepal. It includes 138 species and six subspecies, of which 22 species are endemic and four are introduced. It highlights 34 species recorded for the first time in Nepal and provides new distribution records for another 30 species.  相似文献   

6.
Sanoamuang  La-orsri 《Hydrobiologia》1997,362(1-3):45-53
Examination of 200 samples from 93 freshwater habitats in north-eastThailand revealed 60 taxa of Cladocera, of which 31 are new to the Thaifauna. Six species (Disparalona caudata Smirnov; Leydigialaevis Gurney; Leydigiopsis sp.; Macrothrix flabelligeraSmirnov; Macrothrix cf. paulensis Sars; and Pseudosidaramosa Daday) are new to Asia. The majority of the Cladocera recorded arecircumtropical species. Comments and figures are presented on several ofthe new records for Asia and Thailand. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

7.
Peter B. Vila 《Hydrobiologia》1989,171(3):201-214
Although Cladocera are collected often in large rivers, their importance in streams has been under-estimated. This paper summarizes the results of a preliminary study of the benthic Cladocera in the streams of three watersheds in South Central Indiana. Seventeen sites were sampled with respect to species of benthic Cladocera present, their relative abundance, population size, and population dynamics.Cladocera were present in all streams and sites in the three watersheds. Nineteen species were collected: 13 species from the family Chydoridae, 3 Daphniidae, 2 Macrothricidae, and 1 Bosminidae. Just four species — Alona circumfimbriata, Chydorus brevilabris, Pleuroxus denticulatus, and Macrothrix laticornis — made up 68–96% of the numbers at all sites.Density of Cladocera ranged from 3–5200 m–2 and they reproduced and maintained populations in the streams sampled. Numbers were generally high in October and early November and decreased to near zero in late December and January. The most important factor appearing to affect population sizes was discharge. Numbers at almost all sites decreased significantly after a rainfall increased discharge.A Principal Components and clustering analysis grouped sites with similar physical parameters in a continuum of low to high order. Sites with low numbers of Cladocera were generally shallow, narrow, and had a loose unconsolidated substrate. Sites with high population numbers were generally deep, wide, and had a stable substrate that accumulated detritus.  相似文献   

8.
Sixty species of freshwater Cladocera (Crustacea, Branchiopoda) are recorded from Lake Tonle Sap and its adjacent waters, Cambodia. Four species, Ceriodaphnia laticaudata, Bunops cf. tuberculatus, Leydigia australis, and Chydorus cf. dentifer are newly recorded from Southeast Asia, and occurrence of Macrothrix pholpunthini is secondary confirmed in the world. The present cladoceran fauna is characterized by having rich epiphytic and benthic forms. It can be associated with the shallow and vegetation-rich habitats of the study sites.  相似文献   

9.
The Cladocera of Sri Lanka (Ceylon), with remarks on some species   总被引:5,自引:4,他引:1  
The freshwater Cladocera of Sri Lanka has been revised based on the study of over 700 zooplankton samples collected from all habitat types during 1965–1980. The cladoceran fauna is represented by six families; members of the families Polyphemidae, Leptodoridae and Holopedidae are absent. The common temperate genus Daphnia is rare.Sixty-two species have been recorded from Sri Lanka. Of these, five are new records. Remarks on a few species are given with illustrations. The distribution of Cladocera in different types of habitats is discussed. The greatest species diversity was found in ponds. The Sri Lankan fauna is numerically and in species diversity typical of tropical cladoceran fauna. It resembles the southern Indian fauna very closely except for the absence in Sri Lanka of the genera Acroperus and Camptocercus.  相似文献   

10.
The freshwater zooplankton of Central America and the Caribbean   总被引:2,自引:2,他引:0  
So far mainly sporadic studies have been made on the freshwater zooplankton of this region. We studied material from Costa Rica, Cuba, Bahamas, El Salvador, Haiti and Trinidad and listed unpublished species data from Jamaica. In all 183 species of Rotifera; 104 of Cladocera; 64 Calanoida and Cyclopoida and a few Ostracoda are known from the region which includes Central America, the Caribbean Islands from the Bahamas to Trinidad and the islands off South America and Central America. Records from individual countries are generally low except for Cuban Cladocera and Copepoda. The total number of Copepoda and Cladocera recorded for the whole regions appears to be reasonably comprehensive. Daphnia is rare or absent from the equatorial regions and it is likely that the low species diversity may be due partly to the lack of a range of habitat types.  相似文献   

11.
Amphibians are declining worldwide.At the same time,each year many species of amphibians are described,indicating that biological diversity on Earth remains poorly understood.This is especially true for mountainous regions,such as the Himalayas,which are also regarded as a biodiversity hotspot.However,it is most likely that the current diversity of amphibians in Nepal is highly underestimated.Amphibian inventories by the past researchers primarily used phenotypic characters as the basis for species identification.However,the application of molecular systematics methods to taxonomic studies has successfully uncovered the taxonomic status of several cryptic taxa.This study used both molecular(16 S rDNA sequences)and morphological comparisons and estimated the diversity of amphibians from Nepal.This study reports the occurrence of 38 species of amphibians based on both molecular and morphological comparisons.Among them,three species were recorded for the first time in Nepal.This study also invalids the taxonomic status of Sphaerotheca paschima.This study highlights the importa nce of integrative taxonomic approaches that help to resolve the current taxonomic ambiguities of Nepalese amphibians.  相似文献   

12.
Groundwater Cladocera: A synopsis   总被引:5,自引:5,他引:0  
A review is given of our present knowledge on the Cladocera that live in subterranean waters. Besides species that are accidentally or passively transported to caves and wells, at least one groundwater habitat, namely that of river gravels, is inhabited by species that either do not occur at the surface at all, or are only rarely thrown up by springs. Such species are now known from three continents.  相似文献   

13.
One hundred and thirty species of Cladocera have been recorded from the Indian subcontinent which extends from 6°N to 37°N latitude and covers an area of 4.5 million km2. The equatorial region has few Daphnia species, all belonging to the sub-genus Ctenodaphnia while the more northern parts have more species of Daphni including Daphnia s. str. The limnetic Cladocera lacks the carnivorous Polyphemidae and Leptodoridae at lower latitudes (equatorial). The common limnetic species of the equatorial region are eurytopic and extend throughout the subcontinent.  相似文献   

14.
Cladocera (Crustacea) from Nicaragua   总被引:1,自引:1,他引:0  
Thirty-one Cladocera taxa are recorded from lakes, rivers and ponds of Western Nicaragua. They include Alona bromelicola sp. nov. found in water accumulations in epiphytic Bromeliads. The Cladocera recorded are neotropical and circumtropical. Other invertebrates found are also listed.  相似文献   

15.
Medicinal and aromatic plants (MAPs) contribute to human well‐being via health and economic benefits. Nepal has recorded 2331 species of MAPs, of which around 300 species are currently under trade. Wild harvested MAPs in Nepal are under increasing pressure from overexploitation for trade and the effects of climate change and development. Despite some localized studies to examine the impact of climate change on MAPs, a consolidated understanding is lacking on how the distribution of major traded species of MAPs will change with future climate change. This study identifies the potential distribution of 29 species of MAPs in Nepal under current and future climate using an ensemble modeling and hotspot approach. Future climate change will reduce climatically suitable areas of two‐third of the studied species and decrease climatically suitable hotspots across elevation, physiography, ecoregions, federal states, and protected areas in Nepal. Reduction in climatically suitable areas for MAPs might have serious consequences for the livelihood of people that depend on the collection and trade of MAPs as well as Nepal''s national economy. Therefore, it is imperative to consider the threats that future climate change may have on distribution of MAPs while designing protected areas and devising environmental conservation and climate adaptation policies.  相似文献   

16.
Based on the field studies conducted in August 2005 and 2007, the distributions of zooplankton structure and abundance, as well as chlorophyll content, in the Sheksna Reservoir are analyzed. A total of 107 zooplankton species have been found (46 Cladocera, 18 Copepoda, and 43 Rotifera), including 24 species (10 Cladocera, 2 Copepoda, and 12 Rotifera) new for the reservoir. In the surface layer of water, where blue-green algae concentrate, zooplankton abundance and biomass are 1.5–5 times lower and the zooplankton structure is simpler than in deeper layers. The highest zooplankton biomass (>3 g/m3) are observed in Lake Beloe and the upper area of the Sheksna section, while in the near-shore sites it did not exceed 1 g/m3. There are no significant changes in zooplankton abundance when compared to the abundance recorded at the end of the past century.  相似文献   

17.
Observations on the Cladocera of Lake George, Uganda   总被引:4,自引:0,他引:4  
Mary J.  Burgis 《Journal of Zoology》1973,170(3):339-349
Seven species of Cladocera were recorded from the shallow, equatorial Lake George in Uganda, during the period 1967–72. Of these only three, Moina micrura Kurz, Ceriodaphnia cornuta Sars and Daphnia barbata Weltner, are found in the open water and they form a small proportion of the total zooplankton biomass, which is dominated by a cyclopoid copepod. All three species are found throughout the year and carry parthenogenetic eggs at all times. They are smaller species than those predominating in some other East African lakes and some comparisons are also made between C. cornuta and four other species of that genus studied in Great Britain. The mean body lengths and clutch sizes of ovigerous females of C. cornuta vary little through the year. This is, presumably, a reflection of the relatively constant environment in Lake George. Alona poppei is only found in the open water intermittently and is thought to be swept from the peripheral swamps during heavy rains.
The general scarcity of Cladocera in Lake George is thought to be due, either to a shortage of food particles of suitably small size in the phytoplankton, which is dominated by large blue-green algae, or to predation. Although Cladocera are certainly eaten by fish, quantitative data, with which to substantiate either of these hypotheses, is lacking.  相似文献   

18.
Lichen harvest and trade are closely associated with the livelihood of most of the rural people in Western Nepal. The present study investigates the commercial collection of lichens, quantifies the traded volume and relates it to a market scenario, and discusses conservation measures in relation to established legal practices in Nepal. Data on lichen trade and revenue generated for the 12 years (2000–2011) were collected and analyzed from 74 districts of Nepal. Voucher specimens were deposited at TUCH (Tribhuvan University Central Herbarium) in Nepal. The lichens collected in West Nepal are mainly used in international trade, while those in East Nepal are used locally for food. A total of 20 commercially important species of lichens were identified from five trade centers and one local market. During 2000–2011, Nepal legally exported 2020 tons of lichens and collected NRs 25,293,305 (USD 240,000). The average annual quantity of turnover was 168 tons, though it is estimated that much was exported illegally. The hill districts in Nepal, which traded 1774 tons, were more important for the collection of commercial lichen species than the Mountainous and inner-Tarai districts, which traded 167 and 108 tons, respectively. Through the Forest Act, Forest Regulations and its amendment in 2011, the collection of lichens for harvest, trade and export in any crude or processed form was banned. However, the legislation lacks an effective implementation strategy, and sustainable harvest of lichen resources based on scientific data would better serve local livelihood and lichen conservation in Nepal.  相似文献   

19.
G. O. Sars and the Norwegian Cladocera: a continuing frustration   总被引:4,自引:4,他引:0  
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20.
Thirty-two species of Cladocera and 27 species of free-living copepods were identified in a series of samples collected in 25 localities in and around the Fouta Djalon mountains, West Africa. Beside great richness in numbers of species, the nature of the fauna is noteworthy: at least 20% of the Cladocera and 50% of the copepods are endemic to West Africa. Possible palaeoclimatological reasons for this are discussed. The cladoceran genus Streblocerus is recorded from Africa for the first time. It is an element of northern origin in the fauna of West Africa. More examples of this kind are documented among the Copepoda Cyclopoida and Harpacticoida, but the bulk of the fauna is evidently of tropical origin. In particular, great adaptive radiation is occurring in the local representatives of the genus Tropocyclops. Three new species of Parastenocaris are described; they are the first representatives of this genus found in West Africa.  相似文献   

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