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1.
Extensive series of Amphidromus Albers, 1850 were collectedfrom low-altitude areas (30–500 m above sea level)in Thailand, Laos, Malaysia, Singapore and Indonesia between1993 and 2004. Data on shell colour, genital and spermatophoremorphology, and radular structure are presented. Five speciesof Amphidromus (Amphidromus) are reviewed, of which four occurin Thailand. Intraspecific variation between populations ofAmphidromus (Amphidromus) atricallosus (Gould, 1843) is considered;three subspecies are accepted and a new subspecies described.Subspecies of A. (A.) inversus (Müller, 1774) and A. (A.)schomburgki (Pfeiffer, 1861) are reconsidered, and a new subspeciesof the latter is described. A dichotomous key to the speciesand subspecies of Amphidromus (Amphidromus) in Thailand is provided. (Received 7 May 2004; accepted 31 March 2005)  相似文献   

2.
通过对核桃扁叶甲3个亚种(指名亚种Gastrolina depressa depressa Baly,淡足亚种G. depressa pallipes Chen和黑胸亚种G. depressa thoracica Baly)的比较形态学研究,结合生物学和生物地理学方面的资料,对其分类地位进行了探讨。从形态上来说,三者的上唇、下唇、后翅和爪的形态区别较小,但是触角、上颚、下颚和受精囊则存在着较大的区别,而且通过超微形态的比较,淡足亚种、黑胸亚种和指名亚种均存在着较为明显的形态区别。动物地理学研究表明,指名亚种和黑胸亚种在我国北纬25°~30°之间有地域重叠,目前仅在部分地区可以通过海拔来区分。但是对于淡足亚种而言,它的分布区与其他两个亚种有着一定的地理隔离,其间并没有重叠区的存在。因此从地理分布上而言,三者也存在着不同。通过上述讨论,本文将核桃扁叶甲三亚种恢复或提升为种,即核桃扁叶甲G. depressa Baly,黑胸扁叶甲G. thoracica Baly和淡足扁叶甲Gastrolina pallipes Chen, stat. Nov.。  相似文献   

3.
An unusual carnivorous diet was documented for the rhytididsnail Wainuia urnula urnula (Pfeiffer) from the southern North Island,New Zealand. Eighty-two percent of 315 samples of faeces or gutcontents contained remains of landhoppers (Crustacea: Amphipoda).Earthworms (Oligochaeta) were the second most common food typeidentified, but occurred in only 4 percent of samples. In the laboratory,W. urnula urnula captured landhoppers by rapidly everting theTVU-section odontophore beneath the prey and immediately drawingit into the mouth in a single action. Diet samples from the allopatriccongeners W. edwardi (Suter) (n 5 51) and W. clarki Powell (n5 7) contained no remains of landhoppers, and these snails didnot eat landhoppers in the laboratory. The diet of these specieswas dominated by earthworms. The subspecies W. u. nasuta ateboth earthworms and amphipods with similar frequency (n 5 40).Individual teeth on the radula of W. urnula urnula had a simpleblade-like cusp like other Wainuia species, but there were fewerteeth per row and fewer rows on the whole radula than in otherspecies. W. u. nasuta had a similar number of rows of teethto W. clarki and W. edwardi, but the number of teeth per rowwas intermediate between these species and W. u. urnula. Recordsof pulmonate species preying on arthropods are rare, yet inthe case of W. urnula this specialization has been accompaniedby minimal morphological change. (Received 22 December 1998; accepted 11 March 1999)  相似文献   

4.
The Labidocera pectinata species group is recognized as a uniquemonophyletic lineage within the primarily tropical Indo-WestPacific radiation of coastal water species encompassed by theLabidocera kroyeri complex. Both categories are defined andthe six species comprising the pectinata group, including twonew to science, are diagnosed. Review of available facts supportsthe proposal that L. bipinnata be ranked as a junior synonymof L. rotunda. Phylogenetic relationships within the group basedon sexually modified characters are assessed. Two geminate pairsof parapatric species are identified. The geographic rangesof one pair are adjacent in the Andaman Sea, those of the otherpair in the vicinity of Cape York, Australia. Each pair appearsto be a consequence of a relatively recent speciation event.The apparent phylogenetic intermediacy of L. japonica linkingthe two tropical species of Asia and the three from Papua-Australiasuggests an older sequence of trans-hemisphere spreading anddiversification.  相似文献   

5.
Oncomelania lindoensis from Lake Lindu, Sulawesi, was characterizedfor genetic variation at 21 allozyme loci and compared withO. hupensis (China) and O. quadrasi (Philippines). Geneticdistances and interpopulation patterns of allele-sharing pointto a closer relationship between Sulawesi and the Philippines(Nei's unbiased genetic distances (D) averaged 0.50) than betweenSulawesi and China (D= 0.79). These data, coupled with a considerationof the geographic distribution of the genus, support the hypothesisthat the Sulawesi Oncomelaniaoriginated by avian-facilitated colonizationfrom the Philippines about two million years ago. Oncomelania from Sulawesi were originally described as subspecificallydistinct: Oncomelania hupensis lindoensis. However, the allopatricdistribution, unique alleles at five loci, and significant geneticdistances from congeners in Mindanao and elsewhere in the Philippinessuggest that this taxon should be distinguished as a full specieswithin the Oncomelania hupensis species group, namely: O. lindoensisDavis & Carney 1973. Comparison with published data on variationwithin quadrasi and in three Chinese subspecies of hupensisshowed that D values increase with taxonomic level in this speciesgroup. D averaged 0.15 (0–0.26) within Chinese subspeciesand 0.04 (0–0.13) within the Philippines, but was 0.30(0.20–0.45) between Chinese subspecies, and 0.48–0.80between the three species (hupensis, quadrasi and lindoensis).The genotypic cluster species concept and these multilocus geneticdistances can be used to help define species and subspeciesin these medically important snails. (Received 14 May 1997; accepted 20 April 1998)  相似文献   

6.
Endemic Lavigeria gastropods are diverse and common in the benthosof Lake Tanganyika. We used in situ studies of marked individualsto quantify rates of daily movement by three species, and testthe effects of size, sex, reproductive status and parasitismon movement. Average net travel distance was 50 cm day–1,which corresponds to about 20 times shell length. Male L. coronatamoved significantly farther than L. coronata females or L. grandis,and L. nassa of either sex. There were also significant differencesamong individuals within each group; however, these differenceswere not predicted by size, reproductive status or parasitism.We interpret greater movement of L. coronata males as a reflectionof mate searching; the ratio of males to non-brooding, non-parasitizedfemales was three times as high in L. coronata (21:1) as inthe other species (6:1). Our results indicate that these snailsare capable of moving considerable distances, and that the highlylocalized distribution of L. coronata populations is not simplya reflection of limited movement by individual snails. (Received 20 September 2006; accepted 1 March 2007)  相似文献   

7.
Anthyllis vulneraria L. (Fabaceae) s. lato includes many cryptic taxa, ranging from 25 to 60 subspecies according to different authors. The delimitation of intraspecific taxa of A. vulneraria s. lato has always been complicated and inconsistent. Different data sets (multivariate analyses of morphological variation, allozymes, chloroplast SSRs and ITS) have not resolved the existing problem with distinguishing some subspecies. We used the amplified fragment length polymorphism (AFLP) analysis to describe the differentiation in this species complex and to characterize variation on a geographic scale. Some correlation was found between genetic variability and geographic distribution (western-eastern directional variation), but AFLP data analysis did not reveal clear intraspecific structure of the seven analysed taxa. The analysed specimens did not comprise groups correlated with the subspecies.  相似文献   

8.
The genus Tricolia(Phasianellidae) in the Eastern Atlantic andMediterranean is reviewed on the bases of radular morphology,shell characters and polychromatism. The taxa included within the T. pullus (L.) group are not clearlyseparable and are treated as geographical subspecies:T. pulluspullus (L.), T. pullus picta (da Costa), T. pullus azorica (Dautzenberg),T. pullus canarica Nordsieck. The case of T. tenuis (Michaud)is problematic since it is clearly separable from sympatricT. pullus pullus in most parts of the Mediterranean but transitionalto T. pullus picta, towards the Atlantic. Other taxa are considered as having specific status since theyare consistently separable when found in sympatric populations.These include T. speciosa (Muhlfeldt), T. miniata (Monterosato),T. tingitana n.sp., T. petiti (Craven), T. nordsiecki (Talavera)and T. algoidea (Pallary). The last two species are stated forthe first time as belonging to the Phasianellidae. The genusEpheriella Pallary, based on T. algoidea, is synonymized withTricolia. (Received 6 April 1981;  相似文献   

9.
赤眼蜂分子鉴定技术研究   总被引:16,自引:5,他引:11  
李正西  沈佐锐 《昆虫学报》2002,45(5):559-566
通过对6种常见赤眼蜂,即松毛虫赤眼蜂Trichogramma dendrolimi Matsumura、玉米螟赤眼蜂T. ostriniae Pang et Chen、螟黄赤眼蜂T. chilonis Ishii、广赤眼蜂T. evanescens Westwood、甘蓝夜蛾赤眼蜂T. brassicae Bezdenko及食胚赤眼蜂T. embryophagum (Hartig)之核糖体核糖核酸基因第二内部转录区(rDNA-ITS2)的克隆测序,调用GenBank中同源序列,对不同蜂种的rDNA-ITS2序列进行了多重排比和聚类,探讨了rDNA-ITS2用于赤眼蜂属不同种系统进化关系分析及赤眼蜂分子鉴定的可行性。为了考察rDNA-ITS2在赤眼蜂种下水平鉴定上的可能性,作者收集了我国常见的松毛虫赤眼蜂6个地理种群(黑龙江亚布力、吉林长春、吉林仁和、陕西长安、江苏徐州、广东广州),采用相同方法测定了它们的rDNA-ITS2序列。序列分析结果表明,赤眼蜂种下阶元ITS2序列非常保守,而种间存在明显的遗传差异。通过外群比较发现,rDNA-ITS2只适合于赤眼蜂种一级的分子鉴定。  相似文献   

10.
There is controversy about the phylogenetic relationships betweenIberus gualtieranus and I. alonensis. Some authors considerthem as valid species or subspecies while others believe thatthe flattened shell of I. gualtieranus is an ecotypic adaptationto dry karstic environments. Two fragments of the mitochondrialDNA (partial COI and 16S rRNA) were sequenced and used in maximumparsimony, maximum likelihood and neighbour-joining analyses.Iberus alonensis show two distinct lineages, one from Almeríaand the other one from Granada and Jaén-Córdobaregions. Iberus gualtieranus populations are recovered as aterminal node within the I. alonensis group from Almería.The I. gualtieranus clade shows a polytomy and there are nodifferences between the populations of the three isolated localitieswhere I. gualtieranus is currently distributed. This indicatesthat the geographical isolation of these populations has notresulted in genetic diversification. The results indicate thatthe population of I. gualtieranus from Sierra de Gádorin Almería is the only autochthonous one, while the othertwo populations originated by historical introductions. On thebasis of the differences in shell morphology, together withthe presence of a hybrid zone connecting both taxa in nature,and the possibility of obtaining fertile hybrids under laboratoryconditions, we conclude that these two taxa represent two subspecies:Iberus gualtieranus gualtieranus and I. gualtieranus alonensis. (Received 27 September 2004; accepted 10 March 2005)  相似文献   

11.
A population of Pseudotachea litturata (Pfeiffer, 1851) fromTarifa (Càdiz, Spain) has been studied. The morphologicalresults are compared with those from P. splendida, Iberus gualtierianus,I. alonensis, I. marmoralus, I. guiraoanus and four speciesof the genus Cepaea using, as an exploratory method, the Wagnerparsimony procedure and 18 characters of the shell, genitalsystem and karyotype have been analysed. According to this methodit seems that the taxonomical position of P. litturata in thegenus Pseudotachea is confirmed, and agrees with the phylogeneticalrelationships in this group of species. The genus Cepaea seemsto be well established, although two species groups can be distinguished:C. nemoralis—C. hortensis and C. syluatica—C. vindobonensis.These differ mainly in chromosome number, diverticulum lengthand degree of shell polymorphism. Although the present resultsdo not allow us to clarify the current taxonomical problemswithin the genus Iberus, the species studied seem to belongto a natural group (Received 15 September 1987; accepted 1 January 1988)  相似文献   

12.
Seed of three chickpea (Cicer arietinum L.), three cowpea [Vignaunguiculata (L.) Walp.] and four soya bean [Glycine max (L.)Merr.] cultivars were hermetically stored for up to 2 yearsin various constant environments which included temperaturesfrom —20 to 70 °C and moisture contents (fresh weightbasis) from 5 to 25 per cent. In all cases the survival curvescould be described by negative cumulative normal distributions.The longevity of the various seed lots differed but the valueof the standard deviation (the reciprocal of which gives theslope of the survival curve when percentage germination is transformedto probit) was the same for all cultivars within a species whenstored under similar conditions. Within each species the relativeeffects of moisture and temperature on longevity did not differsignificantly between cultivars. In all three species therewas a negative logarithmic relationship between seed moisturecontent and longevity, but the relative effect of moisture contentdiffered between the species: differences in the longevity ofsoya bean seed as a function of moisture content were less thanfor either cowpea or chickpea. The relative effect of temperatureon seed longevity did not differ between the three species,and the seed of all three species showed increasing temperaturecoefficients for the change in rate of loss of viability withincrease in temperature. The complete pattern of loss in viabilityin all three species can be described by a single equation whichwas developed for barley and has also been shown to apply toonion seed. The constants applicable to the three grain legumeshave been calculated so that it is now possible to predict percentageviability of any seed lot of these species after any storageperiod under a very wide range of storage conditions. Cicer arietinum L., chickpea, Glycine max (L.) Merr., soya bean, Vigna unguiculata (L.) Walp., cowpea, seed longevity, seed storage, moisture content, temperature  相似文献   

13.
On the basis of collections from SW Wales and W Ireland it isshown that small (<5 mm) black and/or white Littorina occurringin the barnacle zone on exposed shores, of the L. neglecta shelltype, comprise three species. From their reproductive anatomythese correspond to L. saxatilis, L. arcana and L. nigrolineata,and are interpreted as analogous barnacle-dwelling ecotypesof these species. This adds to the evidence that L. neglectais not a distinct species, but an ecotype of L. saxatilis. (Received 1 June 1992; accepted 23 June 1992)  相似文献   

14.
The expolinear equation for crop growth (Goudriaan and MonteithAnnalsof Botany66: 695–701, 1990) was fitted to measurementsof above ground dry weight made on two cultivars of each ofthree species, faba bean (Vicia fabaL.), peas (Pisum sativumL.)and lentils (Lens culinarsMedic.), each grown at three densitiesat the University of Reading, UK in 1992 and 1993. The expolinearequation fitted the data well but required frequent samplingto obtain good estimates of the parameters. The equation hasthree parameters,Rmthe maximum relative growth rate,Cma maximumcrop growth rate, andtbthe time at which the crop effectivelyreaches a linear phase of growth.Rmdid not differ between densities,cultivars or species but differed between years.Cmincreasedwith increased density and was lower for lentils than for fababeans or peas.tbdecreased with increased density for faba beanbut not for the other species. Incorporating an extinction coefficientfor solar radiation and the maximum fraction of radiation interceptedenabled reasonably accurate time courses of leaf area indexto be derived, as suggested by Goudriaan (1994. In: MontiethJL, Scott RK, Unsworth MH, eds.Resource capture by crops. Nottingham:Nottingham University Press, 99–110).Copyright 1998 Annalsof Botany Company Expolinear equation, grain legumes, crop growth rate, crop density, relative growth rate, growth modelling, faba bean,Vicia fabaL., peas,Pisum sativumL., lentils,Lens culinarsMedic.  相似文献   

15.
Abstract

An alternative classification of the New Zealand rhytidid genus Powelliphanta O'Connor, 1945 is presented. P. gilliesi (Smith, 1880) and P. hochstetteri (Pfeiffer, 1862) are recognised as species, and the following subspecies are recognised within hochstetteri: h. superba (Powell, 1930); h. lignaria (Hutton, 1880); h. rossiana (Powell, 1930); h. fiordlandica (Climo, 1971). A model is explained which suggests that all described species and subspecies of Powelliphanta are part of a complex ring species. This developed as a result of glacial disjunction of South Island populations and hybridisation across a Cook Strait land bridge formed during the last Pleistocene glaciation.  相似文献   

16.
We report measurements of the number of vessels ending withinthe nodes in comparison with that in the internodes Such measurementshave been carried out during autumn 1982 and 1983 in 1-year-oldtwigs of three species with diffuse-porous wood (Vitis vintferaL. Populus deitoides Bartr and Olea europaea L) and three ring-poroustrees (Juglans nigra L, Castanea sativa Mill, Sophora JaponicaL) In all three species with diffuse-porous wood, a significantlyhigher percentage of vessels ending in the nodes (at the leafgap) was recorded when compared with that in the internodesNo significant differences were found between nodes and internodesin this respect in ring-porous trees. Since vessel ends arecapable of screening out gaseous emboli and/or particles biggerthan 1 µm in diameter, we interpret the nodes of diffuse-poroustrees as stem zones providing safety for the water conductingsystem .The reason why ring-porous trees are likely not to needsuch ‘safety zones’ is also discussed Vitis vinifera L, grapevine, Populus deltoides Bartr, poplar, Olea europaea L, olive, Juglans nigra L, Eastern black walnut, Castanea sativa Mill, European chestnut, Sophora japonica L, Japanese pagoda tree, vessel ends, nodes, internodes  相似文献   

17.
Musa acuminata Colla (Musaceae), the wild progenitor of thecultivated banana, is highly variable in Malaysia and presentsseveral unresolved nomenclatural problems. AFLP was employedto distinguish among three subspecies of Musa acuminata(subsp.truncata and subsp. malaccensis from peninsular Malaysia andsubsp. microcarpa from Borneo) and to examine whether subsp.truncata is a distinct taxon. Eight primer combinations revealedmolecular markers specific for each of the three taxa. UPGMAcluster analysis showed the three taxa were distinct. Subspeciesmalaccensis which is endemic in peninsular Malaysia and subsp.microcarpa which is endemic in Borneo were found to be moresimilar to each other in their DNA patterns than they are tosubsp. truncata, which is endemic to peninsular Malaysia. Sincesubsp. truncata is genetically separate from subsp. malaccensisand subsp.microcarpa , it cannot be regarded as synonymous witheither of these subspecies. This paper sheds light on the nomenclatureof the three subspecies of Musa acuminata. Copyright 2001 Annalsof Botany Company Musa acuminata Colla, truncata, malaccensis, microcarpa, Musaceae, wild banana, genetic diversity, AFLP, DNA fingerprinting  相似文献   

18.
从一种来自中国日行性萤火虫(云南窗萤)发光器官mRNA中克隆、测序并表达了有功能的荧光素酶。云南窗萤荧光素酶的cDNA序列有1 647个碱基,编码548个氨基酸残基。从推测得到的氨基酸序列的比对分析得出:云南窗萤的荧光素酶与来自Lampyris noctiluca, L. turkestanicusNyctophila cf. caucasica三种萤火虫的荧光素酶有97.8%的序列一致性。从推测得出的氨基酸序列进行系统发育分析,其结果表明:云南窗萤和Lampyris+Nyctophila聚在一起, 与同属的发光强夜行性的萤火虫不形成的单系。云南窗萤荧光素酶在大肠杆菌中表达的条带大约70 kDa,并且在有荧光素存在时发出黄绿色荧光。对荧光素酶的结构模拟和分析表明,云南窗萤荧光素酶基因的氨基端和羧基端结构域之间的裂沟处存在这5个多肽环,这正是从其他荧光素酶推测得到的催化荧光反应时的底物结合位点。云南窗萤和窗萤属的其他3种萤火虫的荧光素酶相比,有13个不同氨基酸位点,位于模拟分子结构的表面。对于这些多肽环、不同氨基酸残基和晶体结构的进一步研究有利于解释日行和夜行性萤火虫荧光素酶的差异。  相似文献   

19.
Four subspecies of Cystocnemis discoidea are distinguished; two subspecies are described as new to science based on investigation of intraspecific variation in different parts of the species range, and ssp. gebleri was resurrected from synonymy. The ways of speciation in highland-hollow landscapes are discussed. The alpine subspecies C. discoidea oreas ssp. n. has an altibiome disjunction with the nominotypical subspecies. Similarity of the alpine subspecies of C. discoidea to the species from the subgenus Entomomela was found to be the reason of permanent confusion of representatives of these taxa. The subgenus Entomomela is transferred from the genus Oreomela to the genus Cystocnemis. A key to species and subspecies of the genus Cystocnemis is given.  相似文献   

20.
Solar ultraviolet (UV) radiation poses a threat to most livingorganisms. Aquatic organisms have evolved three basic mechanismsto cope with harmful levels of radiation. Two mechanisms, avoidance(e.g. vertical migration) and photoprotection (e.g. productionof photoprotective compounds that act as filters, antioxidants,etc.), serve to minimize the dose of UV radiation that reachesthe organism's vital structures (DNA, membranes, etc.). Thethird mechanism, repair (e.g. dark repair mechanisms, such asnucleotide excision repair; or photoreactivation mechanisms,such as photoenzymatic repair), serves to repair the damagefollowing UV exposure. Here, we compare the vulnerability toUV-B radiation of three copepod species (Boeckella brevicaudata,Boeckella gibbosa, and Boeckella gracilipes) that occur in lakesthat differ in UV-B penetration and depth. Our aim was to gaininsight into the significance of each of the three mechanismsin different UV-B environments. Results from a 3-day ‘insitu’ incubation in ultra-oligotrophic Lake Toncek showedthat B.gracilipes is highly vulnerable to UV-B and UV-A radiation.In contrast, virtually no mortality was observed in B.gibbosaand B.brevicaudata during the same period. In order to discriminatethe contribution of photoprotection and photoreactivation, thethree species were subsequently exposed in the laboratory toan artificial source of UV-B radiation, both in the presenceand absence of visible radiation (recovery radiation). The photoprotectionpotential (i.e. resistance to UV-B in the absence of recoveryradiation) of B.gracilipes and B.gibbosa was lower than thatof B.brevicaudata. On the other hand, photoreactivation (higherresistance to UV-B in the presence of recovery radiation) wasobserved in B.brevicaudata and B.gibbosa, but not in B.gracilipes.To cope with damaging UV-B levels in nature, B.gracilipes dependsexclusively on the attenuation by the external media (i.e. avoidance).Although B.gibbosa tends to avoid the surface waters of lakes,it also occurs in shallow transparent pools. Most likely itsability to survive in these shallow, high UV environments isdue to its photoreactivation potential. Finally, despite itsoccurrence in highly turbid lakes, B.brevicaudata seems extremelywell suited to cope with UV-B radiation thanks to a combinationof photoreactivation and photoprotection.  相似文献   

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