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1.
错头鳋科Lernaeidae是剑水蚤目Cyclopoida中以第1触短和第1小颚单枝型或退化消失为共同离征的一个自然类群,因此以剑水蚤科Cyclopidae作为外群,把锚头鳋科各属筛选出的性状与剑水蚤科的相应性状比较,以确定其性质,即该性状为祖征,还是离征。经比较,发现21个性状在锚头鳋科11个属中呈镶嵌分布。根据性状的镶嵌分布和简约性原则,推导出锚头鳋科的属间系统发育分支图。 相似文献
2.
1995年6月至9月,在武汉东湖,通过摄食实验和野外调查,作者研究了广布中剑水蚤对裸腹溲和秀体溲的摄食。研究结果证实,广布中剑水蚤能够抓取和摄食裸腹溲和秀体溲。广布中剑水溲对小型裸腹溲的平均摄食率高于大型裸复溲。多重统计结果表明,广布中剑水蚤对大型和大型裸腹溲的摄食率有显著差异(P=0.335),捕食者喜食小型猎物。由于广布中剑水蚤的摄食习性,它对裸腹溲和秀体溲的种群动态有重要影响,但随着鱼产量增 相似文献
3.
近邻剑水蚤对浮游动物的摄食 总被引:6,自引:0,他引:6
近邻剑水蚤能捕获和摄食实验所提供的所有浮游动物,尤喜食小型浮游动物。猎物受攻击的部位发生在头部,背部和腹部。猪物密度、水温、光照强度和昼夜变化对近邻剑水蚤的摄食有重要影响。 相似文献
4.
1995年6月至9月,在武汉东湖,通过摄食实验和野外调查,作者研究了广布中剑水蚤对裸腹zao和秀体zao的摄食。研究结果证实,广布中剑水蚤能够抓取和摄食裸腹zao和秀体zao。广布中剑水蚤对小型裸腹zao的平均摄食率高于大型裸腹zao。多重统计分析结果表明,广布中剑水蚤对小型和大型裸腹zao的摄食率有显著差异(P=0.0335),捕食者喜食小型猎物。由于广布中剑水蚤的摄食习性,它对裸腹zao和秀体zao的种群动态有重要影响,但随着鱼产量增加,广布中剑水蚤对猎物摄食的影响效果被减弱了。 相似文献
5.
亚热带湖泊中一种剑水蚤──Mesocyclops notius Kiefer的形态及生态学研究(英文) 总被引:4,自引:1,他引:4
本文报道了对一亚热带湖泊中的Mesocyclopsnotius的形态及生态学研究。将从扁担塘采得的标本形态学特征与Kiefer和Velde从澳大利亚的标本的形态学特征进行了比较.在扁担塘,M.notius与2种温剑水蚤──ThermocyclopstaihokuensisHarada和T.brevifurcatusHarada为春季和夏季剑水蚤的优势种,而CyclopsvincinusvincinusVljanin为冬季的优势种。 相似文献
6.
突颊剑虻属Bugulaverpa首次在中国被发现,自此分布于旧世界的塞洛提剑虻族Cyclotelini的3个属(环剑虻属Procyclotelus,沙剑虻属Ammothereva和突颊剑虻属Bugulaverpa)均在中国被记录。本文记录中国突颊剑虻属1新种:海南突颊剑虻Bugulaverpa hainanensis sp. nov.。该种额为亮黑色,仅在侧缘各有1个半圆形的灰白粉斑。单眼瘤被灰白粉。中足胫节褐黄色。雌虫生殖叉前缘有2个明显的突起。 相似文献
7.
温度对武汉东湖近邻剑水蚤发育及繁殖的影响 总被引:2,自引:0,他引:2
近邻剑水蚤完成一个世代所需的时间随不同的温度而有差别,在一定的温度范围内,其时间与温度呈正相关,在6.5℃时为64.3天,20℃时仅为20.2天,当25℃时则发育减慢。 相似文献
8.
国剑角蝗科部分属种雌性下生殖板的形态及演化(直翅目:蝗总科) 总被引:3,自引:0,他引:3
从20世纪60年代至今的一些研究已基本肯定了蝗虫雌性下生殖板的分类价值。本文选择了中国剑角蝗科6属10种蝗虫对其雌性下生殖板进行了形态学和演化分析。结果表明雌性下生殖板的形态在研究的6属内都是稳定的,属间差异明显。这6个属的系统发育关系为:(卡蝗属((佛蝗属,戛蝗属),(菊蝗属(蝗属,剑角蝗属)))),这一结果和形态分类是一致的,支持长腹蝗亚科从剑角蝗科分开。文中还分析了剑角蝗科雌性下生殖板各性状的演化方向。 相似文献
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这是五里湖桡足类研究报告的第二部分,即关于剑水蚤目部分,内容包括两科,即长腹剑水蚤科和剑水蚤科,前者只记载了一属一种;后者共描述了10属20种,其中至少有5种是过去在国内尚未记载过,而而且还发见了两个新种(Tropocyclops longiabdominalis sp. 相似文献
11.
Within the genus Mesocyclops the thermocyclopoides species-group is defined on the basis of the presence of spiniform armature on the maxillar coxa. Examination of nineteen, mainly Palaeotropical species of Mesocyclops and nine representatives of the closely related genus Thermocyclops revealed, that the coxal part of the maxillar syncoxa of the species recently unified in the thermocyclopoides group is adorned with distinct rows of big spinules on its frontal surface. This character, with only one known exception in South Indian M. cf. papuensis, is absent in other species of Mesocyclops and all the Thermocyclops studied here. These species have no spinules on the maxillar coxa at all or very tiny scattered ones. 相似文献
12.
The predatory copepod Mesocyclops edax is an important componentof many zooplankton communities where it typically makes extensivedid vertical migrations. To describe the effect of light onadults we measured their photoresponses in the laboratory. Theresponse spectrum is characterized by a wide plateau of greatestsensitivity from about 480 580 nm. These animals areadapted to perceive light during the day since their regionof maximum sensitivity overlaps the spectral region of highestquantal intensity underwater (575 700 nm). The thresholdintensity for positive phototaxis by dark adapted animals wasabout 5 x 101 Wm2 at 540 nm, and they were positivelyphototactic up to an intensity of 5 x 101 Wm2.Above this intensity phototaxis is no longer observed. Light-adaptedanimals were less sensitive than dark-adapted, but their generalpattern of response to light intensity did not differ. Thereis no rhythm in phototaxis. Their photoresponses may providea mechanism for controlling vertical migration so as to minimizeexposure to planktivorous fish.
1Contribution No. 1375-AEL from UM-CEES, Appalachian EnvironmentalLaboratory. 相似文献
13.
Two new species of Mesocyclops from southern China and notes on the genus Mesocyclops in China 总被引:3,自引:0,他引:3
Two new Mesocyclops species, M. mariae n. sp. and M. shenzhenensisn. sp., are described from southern China, the former species from Guangxi province, the latter from Guangdong province. Both species have setules on the medial margin of the caudal rami. Compared with each other, there are some conspicuous differences, such as the spinule pattern of the antenna basipodite, the structure of receptaculum seminis, the armature of coxopodite and basipodite of P4 and the armature of the caudal rami. The paper also compares the two new species with their supposedly closest relatives, M. pseudospinosus Dussart & Fernando, 1988, M. leuckarti(Claus, 1857) and M. pehpeiensisHu, 1943. In addition, other species of Mesocyclops in China are discussed and a key to 10 Chinese species of Mesocyclops is provided. 相似文献
14.
The swimming and feeding behavior of Mesocyclops 总被引:1,自引:1,他引:0
Craig E. Williamson 《Hydrobiologia》1986,134(1):11-19
The swimming and feeding behaviors of Mesocyclops are described from a review of the literature and personal observations.
Mesocyclops exhibits considerable behavioral flexibility in response to environmental stimuli. Mesocyclops edax exhibits an increase in horizontal looping behavior at high prey densities, and performs a tight vertical looping behavior in response to the loss of captured prey. Ingestion rates by Mesocyclops are a complex function of prey density, morphology, and behavior in addition to prey size. Vertebrate predators induce a rapid escape response in Mesocyclops and may be responsible at least in part for their extensive diel vertical migrations. The complex behavioral patterns of Mesocyclops suggest that its distribution and abundance in nature will be distinctly nonrandom and influenced as much by its own behavioral responses as by other external physical factors such as water circulation patterns. 相似文献
15.
Mesocyclops ferjemurami sp. nov. is described from Central Vietnam, North India and Sri Lanka. It differs from all congeners in having a unique spinule ornamentation on the caudal surface of the antennary basipodite: the `leuckarti-type' spinule pattern is supplemented with a group of spinules at the height of implantation of the medial setae, and proximal to this group a triangular spinule field occurs, the longest side of which runs more or less parallel to the oblique row of tiny spinules starting at distal half of the medial rim. It is suggested that Mesocyclops ferjemurami is closely related to Mesocyclops pehpeiensis Hu, 1943 and Mesocyclops papuensis Van de Velde, 1987. 相似文献
16.
MARIA HOYSKA 《Zoological Journal of the Linnean Society》2006,147(1):1-70
Evolutionary relationships were investigated in the genus Mesocyclops, a pantropical freshwater cyclopid group. In the phylogenetic analyses that involved all 71 known species, and used 81 morphological characters (265 character states) mainly of the adult females, two different approaches were applied: global parsimony, and a new distance method based upon the recognition of sister‐groups on the basis of minimal distances iteratively corrected for unique character states (MICSEQ). In coding of the characters, half of which showed intraspecific variation, the ‘scaled’ method was employed, which assumes that any trait between its absence and fixed presence passes through a polymorphic stage. Impact of the reference points on topology of the trees generated by the parsimony method was tested in three ways where the outgroups comprised: (1) nine species representing six genera of two subfamilies; (2) three species from two genera supposedly not distant from Mesocyclops; and (3) one presumably close and one distant relative of Mesocyclops. The trees generated by the parsimony‐based and corrected distance methods agreed as to the monophyly of the following groups: reidae‐clade (M. reidae, M. chaci, M. yutsil); rarus‐clade (Mesocyclops annae, M. pseudoannae, M. splendidus, M. rarus, M. paludosus, M. darwini, M. dayakorum); annulatus‐clade (Mesocyclops intermedius, M. ellipticus, M. paranaensis, M. annulatus, M. tenuisaccus); meridianus‐clade (Mesocyclops meridionalis, M. varius, M. venezolanus, M. brasilianus, M. pseudomeridianus, M. meridianus); major‐clade (Mesocyclops major, M. pilosus, M. insulensis); dussarti‐clade (M. dussarti, M. dadayi, M. isabellae, M. thermocyclopoides); pubiventris‐clade (M. pubiventris, M. medialis, M. brooksi, M. notius). A majority of the analyses support a clade of the ‘true’Mesocyclops including all ingroup species except the reidae‐group, and point to monophyly of the Old World species lacking medial spine on P1 basipodite. There were, however, some components for which the two procedures, regardless of the outgroup choice and/or character set, suggested different relationships. Basal relationships of Mesocyclops[between M. edax (North and Central America), the Neotropical species (M. longisetus, M. araucanus, M. evadomingoi, meridianus‐ and annulatus‐clade), Old World group (P1 basipodite without medial spine) and the rarus‐clade (Old World; P1 basipodite with medial spine)] remained unresolved. © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society, 2006, 147 , 1–70. 相似文献
17.
广布中剑水蚤对裸腹和秀体的摄食(英文) 总被引:2,自引:0,他引:2
YANG Yu-feng 《动物学研究》1998,(1)
1995年6月至9月,在武汉东湖,通过摄食实验和野外调查,作者研究了广布中剑水蚤对裸腹和秀体的摄食。研究结果证实,广布中剑水蚤能够抓取和摄食裸腹和秀体。广布中剑水蚤对小型裸腹的平均摄食率高于大型裸腹。多重统计分析结果表明,广布中剑水蚤对小型和大型裸腹的摄食率有显著差异(P=00335),捕食者喜食小型猎物。由于广布中剑水蚤的摄食习性,它对裸腹和秀体的种群动态有重要影响,但随着鱼产量增加,广布中剑水蚤对猎物摄食的影响效果被减弱了。 相似文献
18.
The diel migration patterns of Mesocyclops edax and its preyin a small lake were followed in two studies separated by approximatelyone year. Gut contents of the predators were examined and selectivityindices calculated at each depth at 0100 h during 1980. Thethree principal zooplankton prey found in the guts of M. edaxwere Keratella, Kellicottia, and Bosmina. The predator and allthree major prey species exhibited unique and different dielvertical distribution and migration patterns. The complex natureof the spatio-temporal variation in prey density to which M.edax is exposed, demonstrates the dangers of using selectivityindices without knowledge of the distribution patterns of bothpredator and prey. An increase in vertebrate predation pressurefrom one year to the next is thought to be responsible for anincrease in the abundance of small zooplankton species, thedisappearance of two out of three of the large zooplankton species,and the onset of a pronounced nocturnal migration pattern inthe third large species.
1Present address: Biology Department, Williams Hall #31, LehighUniversity, Bethlehem, PA 18015, USA 相似文献
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The results of four laboratory experiments suggest that Mesocyclops edax selectively preyed upon Bosmina longirostris, given Daphnia parvula and Diaptomus pallidus as alternative prey. These results support an earlier hypothesis (DeCosta & Janicki, 1978) that M. edax may act as an important determinant of the crustacean plankton community structure in an acid lake devoid of planktivorous fishes. 相似文献