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1.
A new species of the genus Daphniopsis found in Australian salt lakes is described and illustrated. A differential diagnosis and short taxonomic remarks are presented.  相似文献   

2.
Forty nine characters were measured in each of 76 male and 200 female Daphnia including specimens from all eleven taxa described from the genus in Australia, except D. jollyi. Separate multivariate analyses (cluster, principal components and discriminant) of males and females each revealed only five morphological groups in the genus corresponding to the species D. occidentalis, D. lumholtzi, D. cephalata, D. nivalis, and a conglomerate of all other taxa described from the D. carinata complex, D. carinata (sensu lato). Interpretation of the male results was straightforward, but that for females was not because of the occurrence of an environmentally induced seasonal change in morphology (cyclomorphosis) in females. Log transformations of the female data successfully isolated the effects of cyclomorphosis. The seasonal morphs formed two groups which were further differentiated into taxonomic groups.  相似文献   

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4.
Daphniopsis pusilla Serventy, an endemic species of cladoceran found in Australian salt lakes, is redescribed. It occurs in both the south-west and south-east of Australia (including Tasmania), and at salinities between about 2 and 71‰  相似文献   

5.
The paper deals with Cladocera and Copepoda species from eight high altitude lakes in the Khumbu area. In all lakes, an endemic known diaptomid of the palearctic genus Arctodiaptomus is found. The dark and large Daphnia tibetana occurs in five of the lakes sampled, characterized by the persistence of the spine in adults (parthenogenetic and ephippial females, males). Apparently, this is an unknown feature of this species. The literature on the diagnostic traits of the different morphs described is reviewed. In addition, a transparent and smaller-sized Daphnia species occurs in two lakes. This is a D. longispina characterized by the absence in adults of the carapace spine (var. aspina Weretschagin, 1911). The presence of these two species is discussed in relation to water transparency, colour, and vertical distribution. Two hypotheses on the evolution of cuticular pigmentation in Daphnia are examined. In addition to these mostly dominant species, a macrothricid also typical of high altitude lakes in the Alps was found (Macrothrix hirsuticornis) together with two cosmopolitan Chydoridae.  相似文献   

6.
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   

7.
Genetic variation at eleven allozyme loci was scored in approximately 1600 individual Daphnia. The samples included representatives of all nine taxa described from the D. carinata complex in Australia. Principal coordinates and cluster analyses revealed only three groups of genotypes within the complex, corresponding to the taxa D. cephalata, D. nivalis, and a conglomerate of all other taxa described from the complex, D. carinata (sensu lato). These results are consistent with recent multivariate morphological analyses of the complex.  相似文献   

8.
Daphnia (C.) hispanica n. sp. has thoracic limbs of A D. (C.) atkinsoni type and is very similar toD. chevreuxi Richard, 1896. With this speciesD. (C.) hispanica shares the presence of a soft accessory seta on the outer side of the trunk of the first thoracic limb, apparently unique among the genusDaphnia. Although other morphological characteristics are very similar in this two species, a detailed comparison reveals that they can easily be separated as different species. The most useful features in differentiating both species are:D. (C.) hispanica has a dorsal crest in the head, its rostrum is longer, its accesory seta of the first thoracic limb is more developed, the juveniles are not helmeted and its male postabdomen lacks individual denticles on the anal and preanal margin.The new species is, up to now, restricted to Spain and inhabits the temporary and low mineralized waters of the steppe regions.  相似文献   

9.
Twelve species ofCeriodaphnia were examined by light and scanning electron microscopy for the presence of head and carapace pores. Rostral pores, similar to those in the Scapholeberinae (Dumont & Pensaert, 1983) were found in all species, situated just anterior to or between insertions of the antennules. With two exceptions, the pattern of reticulations around the pores was distinctive for each species. Oval ‘head pores’ or fenestrae occur consistently on the anterior surface of the cervical notch of juvenile and adultC. dubia, cf.dubia (from Australia),lacustris, andreticulata. The patterns of reticulations around a fenestra are unique to each species. It appears thatC. cornuta (s.l.) in the Americas has a fenestra, whereas AustralianC. cornuta (s.s.) has none. Minute pores often occur bilaterally anterior and posterior to the cervical notch in heavily reticulated individuals of several species but are not constant enough to be taxonomically useful. Well-defined small pores are situated within narrow reticulations just medial to the ventral and posterior valve margins ofC. dubia, lacustris, andreticulata. These open into carapace glands of unknown, perhaps secretory, nature. Similar glands have been observed in related taxa. Such glands and marginal pores occur only occasionally or not at all in otherCeriodaphnia. Other small pores sometimes occur among reticulations of the head, fornix, and lateral and antero-ventral surfaces of the valves. They are found more often in juvenile or heavily reticulated individuals. As yet no consistent pattern to their occurrence among species has emerged. Head and carapace pores inCeriodaphnia may be most useful in identifying species rather than in determining species groups or evolutionary patterns within the genus.  相似文献   

10.
Nitokra humphreysi sp. nov. (Harpacticoida: Ameiridae) is described from anchialine ground waters of the Cape Range karst area in northwestern Australia. The new species belongs to those species of the genus Nitokra Boeck, 1865 with a reduced number of spines/setae on the basoendopodite of the female fifth leg. It is remarkably similar to N. reunionensis Bozic, 1969 and to N. laingensis Fiers, 1986, but there are clear distinguishing features. Nitokra humphreysi sp. nov. has clear stygomorphic features, being colourless and lacking the nauplius eye.  相似文献   

11.
Summary The adult sizes and reproductive capabilities of populations of the cladoceran Daphniopsis studeri Rühe from freshwater and slightly saline lakes in the Vestfold Hills, Princess Elizabeth Land were monitored during December, 1990. The population of Crooked Lake was studied in detail from July 1990–March 1991. Limited samples were also obtained from Heard Island (sub Antarctic). Obligate parthenogenesis involving the production of subitaneous eggs appears to be the case. No males occurred. The overwintering populations of continental Antarctica consist mainly of adult females containing extensive fat reserves. The main reproductive effort occurs in spring. some females produce a smaller second brood during the summer. Reproductive output increases with adult size which is related to the nutrient status of the lake and its productivity. The Heard Island populations have a higher weight to length ratio than the Vestfold populations and have a much greater reproductive output.  相似文献   

12.
Previously only a single species of Ilyocryptus Sars , 1862 (Cladocera: Anomopoda: Ilyocryptidae) was reported from Thailand, I. spinifer Herrick , 1882. However, our examination of numerous samples from this country resulted in the discovery of four other species of Ilyocryptus. Ilyocryptus thailandensis sp. nov. is described from two adjacent water bodies in Uttaradit Province, North Thailand. It has at least two characters which distinguish it from any other species of the Ilyocryptus: (1) a row of lateral setae reaching medial anus, and continuing along preanal margin up to base of the postabdomen; (2) a large projection bearing the sensory setae, situated on the coxal region of antenna II. It appears to be a rare species, may be, endemic of the North Thailand.  相似文献   

13.
Three novel isolates of haloalkaliphilic archaea, strains IHC-005T, IHC-010, and N-1311T, from soda lakes in Inner Mongolia, China, were characterized to elucidate their taxonomic positions. The three strains were aerobic, Gram-negative chemoorganotrophs growing optimally at 37–45°C, pH 9.0–9.5, and 15–20% NaCl. Cells of strains IHC-005T/IHC-010 were motile rods, while those of strain N-1311T were non-motile pleomorphic flats or cocci. The three strains contained diphytanyl and phytanyl-sesterterpanyl diether derivatives of phosphatidylglycerol and phosphatidylglycerophosphate methyl ester. No glycolipids were detected. On phylogenetic analysis of 16S rRNA gene sequences, they formed an independent cluster in the Natro group of the family Halobacteriaceae. Comparison of their morphological, physiological, and biochemical properties, DNA G+C content and 16S rRNA gene sequences, and DNA-DNA hybridization study support the view that strains IHC-005T/IHC-010 and strain N-1311T represent separate species. Therefore, we propose Natronolimnobius baerhuensis gen. nov., sp. nov. for strains IHC-005T (=CGMCC 1.3597T =JCM 12253T)/IHC-010 (=CGMCC 1.3598=JCM 12254) and Natronolimnobius innermongolicus sp. nov. for N-1311T (=CGMCC 1.2124T =JCM 12255T).  相似文献   

14.
A new species of the genus Zygozyma, Z. suomiensis, is described, based on the study of a single strain, derived from a bovine skin lesion.  相似文献   

15.
16.
Six strains of a new purple sulfur bacterium were isolated from the chemocline of four different freshwater lakes. Single cells were spherical to oval, nonmotile and contained gas vacuoles in the central part of the cytoplasm. All strains contained bacteriochlorophyll a and okenone as the major carotenoid. The intracytoplasmic membrane system was of vesicular type. All strains resembled each other in growth conditions and utilization of simple organic carbon sources. The strains were able to grow microaerophilic in the dark, used hydrogen sulfide, elemental sulfur or thiosulfate as electron donor, and lacked assimilatory sulfate reduction. On the basis of all characteristics the new bacterium represents a new species of the genus Amoebobacter, A. purpureus sp. nov.  相似文献   

17.
A new, soil-associated species of the genus Debaryomyces, D. udenii, is described. The species is characterized by pusticulate rather than verrucate ascospores, and slowly lytic asci.  相似文献   

18.
The induction of gamogenesis in a dicyclic population of Scapholeberis armata from a small pond at 40° N in Pennsylvania, USA, was studied. Animals were collected at the time of gamogenesis in mid-October (fall) 1988 and early June (spring) 1989). 10 clones were established from isolated females for each season and maintained at low density under standard conditions of 20 °C and 13.5L/10.5D, with Chlamydomonas reinhardtii diluted with pond water to 3 · 105 cells ml–1 as a food source. For each clone, mothers of pairs of test animals were acclimated to 4 sets of conditions: 20 °C/15.5L (spring), 15 °C/11.5L (fall), 20 °C/11.5L (control), and 15 °C/15.5L. Test animals were observed bidaily or daily for up to 37 days. Occurrence of molts and of parthenogenetic broods or ephippia was recorded. At short photoperiod, ephippial females developed, usually after one or more parthenogenetic broods, among both spring and fall animals. The response was stronger (higher % sexual females) among fall clones, and was enhanced in both groups by 15 °C water. No animals responded to long photoperiod in warm or cool water. It is likely that additional factors, such as prior photoinduction, rapid depletion of food supply, and increased inter-animal contact due to high population density are required for the induction of spring gamogenesis. Differences in the responsiveness of spring and fall clones to inducing conditions suggest some differences in genotypes of spring and fall subpopulations in this pond. It is proposed that variable responses among genotypes to factors inducing gamogenesis may be the basis for the differences and clines in the timing of gamogenesis found among ecologically and latitudinally separated populations.  相似文献   

19.
Three new species of Candida and a new species of Trigonopsis are described based on their recognition from phylogenetic analysis of gene sequences from large subunit ribosomal RNA, ITS1/ITS2 rRNA, mitochondrial small subunit rRNA and cytochrome oxidase II. Candida infanticola sp. nov. (type strain NRRL Y-17858, CBS 7922) was isolated from the ear of an infant in Germany and is closely related to Candida sorbophila. Candida polysorbophila sp. nov. (type strain NRRL Y-27161, CBS 7317) is a member of the Zygoascus clade and was isolated in South Africa as a contaminant from an emulsion of white oil and polysorbate. Candida transvaalensis sp. nov. (type strain NRRL Y-27140, CBS 6663) was obtained from forest litter, the Transvaal, South Africa, and forms an isolated clade with Candida santjacobensis. Trigonopsis californica sp. nov. (type strain NRRL Y-27307, CBS 10351) represents a contaminant from wine in California, and forms a well-supported clade with Trigonopsis cantarellii, Trigonopsis variabilis and Trigonopsis vinaria.  相似文献   

20.
Two interesting chydorid Cladocera were found in caves of Hercegovina and are described here. The pantropical Alona diaphana King, 1853 was already known in this part of Europe, but was found in a cave environment for the first time. Alona hercegovinae n. sp. is an eyeless and stygobiontic species, and was found in three caves.  相似文献   

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