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1.
The postembryonic development of five representatives of Tisbidimorpha Lang, 1948 is described and discussed in the light of the phylogenetic relationships among the taxa. The copepodids of Scutellidium hippolytes, Tisbe gracilis, Drescheriella glacialis (all 3 belonging to Tisbidae), Tegastes clausi (Tegastidae), and Alteutha interrupta (Peltidiidae) are compared. Copepodids of Tegastidae and Peltidiidae are described for the first time. Copepodid synapomorphies support the close relationship of the 3 representatives belonging to Tisbidae on the one hand and the representatives of both, Tegastidae and Peltidiidae on the other hand. S. hippolytes exhibits copepodid characters which are peculiar for Scutellidium.  相似文献   

2.
Hans-Uwe Dahms 《Hydrobiologia》1990,202(1-2):33-60
The first nauplius and 5 copepodite stages ofThalestris longimana Claus, 1863 are described. Sexual dimorphism makes its first appearance in the copepodid IV. Brief remarks are given on cultivation and on ecology of the species. The significance of both the naupliar and the copepodite development for the reconstruction of phylogenetic relationships of Thalestridae is discussed.  相似文献   

3.
4.
All the postembryonic developmental instars of Phyllodiaptomus blanci (Guerne & Richard, 1896), reared in the laboratory, are described and illustrated. The larval affinities of this species vis-a-vis certain other diaptomid species are mentioned.  相似文献   

5.
6.
Benthic harpacticoids were collected for the first time at Lake Tahoe, California-Nevada, United States. Two species were identified as members of the genus Attheyella Brady, 1880. The genus Attheyella comprises about 150 species within six subgenera, but only twelve species have previously been reported from North American freshwater habitats. The two new species of Attheyella described here have a 3-segmented endopod on P1 and 2-segmented P2–P4 endopods, the distal segment of exopod of P2–P4 has three outer spines, and the P5 has five setae on the exopod and six setae on the baseoendopod. Attheyella (Attheyella) tahoensis sp. n. most closely resembles Attheyella (Attheyella) idahoensis (Marsh, 1903) from Idaho, Montana, and Alaska (United States) and Attheyella (Attheyella) namkungi Kim, Soh & Lee, 2005 from Gosu Cave in South Korea. They differ mainly by the number of setae on the distal endopodal segment of P2–P4. In addition, intraspecific variation has been observed on the caudal rami. Attheyella (Neomrazekiella) tessiae sp. n. is characterized by the extension of P5 baseoendopod, 2-segmented endopod of female P2–P3, and naked third seta of male P5 exopod. The two new species are likely endemic to Lake Tahoe, an isolated alpine lake within the Great Basin watershed in the western United States.  相似文献   

7.
Taxonomic and ecological studies of freshwater harpacticoid copepods are limited globally by the ability to easily and accurately identify specimens. Here, we test the use of the mitochondrial cytochrome c oxidase subunit I (COI) gene locus as a tool for assessing the diversity of freshwater Harpacticoida. We obtained sequences from New Zealand harpacticoid copepods, representing two families, five genera and nine species, including the non-indigenous Elaphoidella sewelli. All species were delineated by the COI gene. However, high intraspecific diversity was evident among populations of Elaphoidella bidens (>12%), and between North and South Island populations of Bryocamptus pygmaeus (>18%), potentially indicating the presence of morphologically cryptic taxa. We suggest that mitochondrial DNA (COI) sequences can provide a useful tool for the routine identification of freshwater harpacticoid copepods. Applications of these data will include assessing species diversity and biogeography as well as assisting with the detection of non-indigenous species.  相似文献   

8.
The post-embryonic development of Psammopsyllus maricae Cottarelli, Saporito & Puccetti, 1983 has been described for the first time. Six morphologically distinct naupliar and five copepodid stages were discerned and studied using light microscopy. Some features were also examined by scanning electron microscopy.  相似文献   

9.
Partitioning of the ingested energy in harpacticoid Tisbe carolinesis was investigated with 14C labelled diatom Cylindrotheca sp. (Strain N-1) as food source under laboratory conditions (salinity 30 ppt, 24 ± 1.5°C). Over a 24 hr period, egg sacs and fecal pellets produced per T. carolinesis were 0.64 and 1.19, respectively. Radioactivity measured in the body accounted for 49.1% of the ingested radioisotope, whilst 42.3% of the energy was channneled into reproduction. Respiration and excretion took up 4.9% of the energy and the rest, 3.7%, went into fecal pellets.  相似文献   

10.
All six naupliar and five copepodite stages of Tisbe gracilis (T. Scott, 1895) are described. A key for the identification of the nauplius stages is given. The oral appendages of all copepodite stages are described. Sexual dimorphism is visible from the copepodite IV stage on.  相似文献   

11.
海南黎、苗、汉族扣手、交叉臂和惯用手的研究   总被引:23,自引:3,他引:23  
调查了海南居住较为集中的黎、苗、汉族(共3 207人)扣手、交叉臂、惯用手等人类左右不对称行为特征。结果显示:(1)扣手、交手臂、惯用手三型3个民族的出现率均为R>L型,惯用手的R型出现率远较其他两型高,呈高度显著性差异,(P<0.01)。(2)扣手、交叉臂出现率与性别无关。(3)惯用手R型出现率苗族女性明显高于男性,差异显著(P<0.05)。三民族总和出现率为89.06%,是国内外属最低的。(4)扣手与交叉臂、扣手与惯用手,交叉臂与惯用手之间均具有相当明显的相关性。 Abstract:It was investigated that three types of many general indexes of anthrotogical genetics,which include hand-clasping、arm-folding and handedness,just among Li,Miao and Han nationalities in Hainan.There were 3207 people investigated in total.The results showed as follows:(1)The frequency of hand?clasping,arm-folding and handedness is far higher than others(P<0.01).(2) It was proved that there was no signilicant difference between male and female in the frequency of either hand-clasping or arm-floding.(3)It was obvious that the frequency of type R handedness in female of Miao nationality was higher than in male.And the difference was much clear(P<0.05).The total frequency of handedness was about 89.06 percent,which was the lowest rate as far as we known.(4)There was correlation among handedness and hand?clasping,handedness and arm-folding andhand-clasping and arm-folding respectively.  相似文献   

12.
A total of 30 weekly exploited populations of the harpacticoid copepodTisbe holothuriae Humes were exposed to 148 or 222µg Cd++ l–1, combined with exploitation rates of 10, 30, 50, 70 or 90% under conditions of surplus food supply at 22 °C and 30 S. During the observation period, most populations exhibited distinct U-shaped density trends. Addition of Cd++ prolonged and reinforced the downward trends present in the initial periods of the experiments. If population densities, both in control and test populations, fell short of a certain value, the age structures shifted in favour of the nauplii. More pronounced reductions in population densities of the test populations did not result in increased elevations of the nauplius fraction. Within 23 weeks (or 20 generations), the effect of Cd++ on population density was counteracted by an acclimation process. No relationship could be established between exploitation rate and observed effects. Erroneous assumptions on the adaptability of parametric methods had led to invalid statements on the dispersion of data published in previous papers of this series. These statements have been revised. Possible limitations of the significance of the results obtained are discussed in some detail.  相似文献   

13.
A total of 75 weekly exploited populations of the harpacticoid copepodTisbe holothuriae Humes were exposed to 0.06, 0.3, 1.5, 7.5 or 37.5 μg Cd++l?1, combined with exploitation rates of 10, 30, 50, 70 or 90% under conditions of surplus food supply at 22° C and 30‰ S. An unusually high mortality was observed for some weeks which could not be ascribed to the added amounts of Cd++. A change in properties of supplied water is considered responsible for the unintentional perturbation which offered a further opportunity to study the effect of compensating reactions in stress situations. The results obtained clearly indicate an effect of exploitation rate on responses to detrimental influences. A superior performance has been found in populations exploited at higher rates. The findings are discussed with respect to earlier investigations on the population dynamics ofT. holothuriae.  相似文献   

14.
The new species Quinquelaophonte aurantius sp.nov. is described, based on specimens collected in Portobello Bay, New Zealand. The species is distinguishable for having long fine setules in the anal operculum distal edge, a breadth ratio of caudal rami length above 3.5, and a rudimentary antenna abexopodal spine. This new species differentiates from Q. parasigmoides and Q. wellsi on the following autapomorphs; short spine-like outer seta in segment 2 of females P3 endopod and the partial reduction of setae in spines from male P3 and P4, longer V-shaped caudal rami, an almost non-existent terminal portion of the antenna exopod with short lateral setae. Phylogenetic analyses demonstrate the position of Quinquelaophonte within the family Laophontidae.

Publication LSID: urn:lsid:zoobank.org:pub:D5E5EB23-8348-446D-9606-EA8B27EC0EDC

LSID for Q. aurantius: urn:lsid:zoobank.org:act:834C4218-209B-4B70-8AD5-35512B5FCB29  相似文献   


15.
Abstract Morphological studies of development of the egg parasitoid Trichogramma australicum Girault in the cotton bollworm, Helicoverpa armigera (Hübner), were conducted to provide benchmarks for assessing developmental rates in both natural hosts and artificial diets. Observations of living embryos and histological sections show that embryos proceed rapidly through cleavage and blastoderm formation and show a characteristic pinching or rotation 8 h after deposition. Eggs progressively increase in volume, primarily by increasing in diameter at the widest point. At 29 ± 1°C the duration of the egg stage is 22−24 h, the larval stage 27 h, the prepupal stage 50−52 h, and pupa 85 h. Larvae undergo dramatic shape changes as they ingest food but do not show signs of larval moults, reinforcing observations that there is only one larval instar. Criteria for staging the embryonic and postembryonic development in natural hosts will be used for future studies aimed at developing and refining artificial diets for Trichogramma.  相似文献   

16.
17.
A new genus and new species of the family Cletopsyllidae Huys & Willems, 1989 from deep-sea sediment in the Gulf of Mexico, are reported and fully described and illustrated. The new genus Pentacletopsyllus (type species: P. montagnisp. n.) can be distinguished from the four known genera of the family by antennule segmentation, length ratio of first and second endopodal segments of P1, and armature pattern on P5 exopod. It also differs from its sister genera by the rostrum being bifid at the tip, third segment of the female antennule having a smooth posterior margin, the baseoendopod of P5 with biarticulate outer setophore bearing basal seta, and female caudal rami without lobate expansion. A revised key to species of the family Cletopsyllidae Huys & Willems, 1989 is provided.  相似文献   

18.
On the ecology of marine cyclopoid copepods (Crustacea, Copepoda)   总被引:19,自引:1,他引:18  
The goal of these studies was to improve our understanding ofhow Oithonidae and Oncaeidae can exist in nearly every partof the ocean. In particular, it was intended to obtain quantitativeinformation on reproduction rates and the longevity of adultfemales, and on feeding and growth rates of Oncaeidae. Whenfeeding at relatively high food levels, early copepodids ofOncaea mediterranea ingested  相似文献   

19.
Six nauplius and five copepodid stages as well as adults ofParalabidocera antarctica (I. C. Thompson, 1898) (Copepoda:Calanoida) are described based on specimens obtained from fast ice and collected by a plankton net near Syowa Station (69°00 S, 39° 35 E), Antarctica. The adult male and female are redescribed in detail. Nauplius stages ofP. antarctica are very similar to the previously describedAcartia species. Sexual dimorphism becomes apparent from copepodid IV onwards in the morphology of antennule and leg 5. The copepodid stages of this species retain certain characteristics not only of Acartiidae but also of Pontellidae and Parapontellidae.  相似文献   

20.
J. Sarvala 《Hydrobiologia》1979,62(2):113-129
The harpacticoid copepod Canthocamptus staphylinus (Jurine) was shown to reproduce parthenogenetically in an oligotrophic Finnish lake. The population was univoltine with peaks of egg production in winter and early spring. Young from both peaks became adults in spring and aestivated as cysts. Laboratory experiments suggested that either high temperature (12 °C or more) or long days will inhibit egg production, but that both factors together are needed to induce encystment. Embryonic survival was low, on the average only 60%. The population was limited by low food levels in winter, and it is suggested that food shortage prevents the species from colonizing the profundal zone of oligotrophic lakes.  相似文献   

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