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1.
Joseph C. Britton 《Hydrobiologia》1995,309(1-3):129-142
Shells of small (< 7 mm) Littorina striata are frequently nodulose, but shells of larger individuals are striate. Nodulose L. striata dominated the littoral fringe of a black basalt Azorean shore where daytime rock temperatures rose significantly higher than nearby shores of different rock composition or colour. There was no evidence of intraspecific size-partitioning on the latter shores, where the numbers of striate and nodulose L. striata were approximately equal between high eulittoral (low-shore) and high littoral fringe (high-shore) localities. The prevalence of small L. striata in the littoral fringe is opposite to that usually characteristic of the Littorinidae, where the largest individuals usually occupy the higher positions on the shore. It is hypothesized that small L. striata attain a resting posture better able to minimize heat absorption from the substratum than attained by larger individuals. Smaller individuals also take advantage of both posture and a nodulose shell surface to re-radiate absorbed incident radiant thermal energy more effectively to the atmosphere by convection. Thus, small, nodulose L. striata are especially well adapted to occupy geologically young basaltic rocks commonly found fringing islands of the mid-Atlantic. The rate of evaporative water loss was determined for Melarhaphe neritoides and striate and nodulose L. striata for approximately 11 days emersion. All three groups are exceptionally capable of controlling evaporative water loss. Total percent evaporative water loss by nodulose L. striata (17.9%) was significantly greater than that lost by either striate L. striata (14.1%) or M. neritoides (13.5%) but, among 15 species for which evaporative water loss has been determined by similar methodology, M. neritoides and striate L. striata are the most capable of conserving body water during 11 days of emersion.  相似文献   

2.
Acrylonitrile butadiene styrene (ABS) pipes are considered to be immune for boring organisms. However, inspection of the offshore cooling water conduits of Lumut combined cycle power plant, Malaysia show that ABS pipes may not necessarily be immune for wood boring pholads, Martesia striata. M. striata caused heavy damage by drilling holes in ABS pipes used (about 5 years) for transportation of hypochlorite from the station towards the intake domes. Hole sizes ranged from 3 to 19 mm2 with an average of 11 mm2. Unlike other boring animals (e.g. Lithophaga), M. striata penetration is not assisted by chemical dissolution of the substrates and therefore, attack is not limited to calcium carbonate substrates. In this context, material like low dense concrete and rocks, wood, PVC, ABS, etc. is subject to attack of M. striata. It is unknown which synthetic polymerics can be expected to be completely immune for boring bivalves.  相似文献   

3.
江门海关从冈比亚进境的刺猬紫檀木原木中检出活体长蠹科昆虫.通过显微形态特征的观察和测量,对该虫进行了物种鉴定.经形态特征鉴定,该虫为小楔双棘长蠹.该虫的形态特征与近似种的主要区别:斜面毛被稀疏、不太明显,近缝角处竖立短直;缝侧齿基部不粗糙;斜面侧上缘有3对胝状的痕迹显现.该虫在我国尚无分布记录,为国内口岸首次截获.该虫...  相似文献   

4.
Three new species and one new genus of dicotyledonous woods,Chilechicoxylon microporosum gen. et sp. nov.,Proteoxylon patagonicum sp. nov. andLaurinium beilschmiedioides sp. nov., are described from the Tertiary (or in case of the first and last species from the Cretaceous-Tertiary) of Chile Chico, XI Region, Chile. Previously only wood of temperate species has been identified from Patagonia.Proteoxylon patagonicum (Proteaceae) is the first recorded tropical wood species from this geographical area. Consecutive number from the previous paper (M. Nishida, H. Nishida and T. Nasa, 1988). Contributions from the Laboratory of Phylogenetic Botany, Chiba University No. 120 and contributions from Chiba University Botanical Expedition to the Andes No. 20. Supported by a Grant-in-Aid for Overseas Scientific Research from the Ministry of Education, Science and Culture Nos. 61041015 and 63041034.  相似文献   

5.
Maculinea butterflies obligatory parasitize certain species of Myrmica ants. Thus, the presence of the host ant species is a limiting factor for the survival of a Maculinea population. Here, we analyse the influence of vegetation structure and ground temperature on ant diversity and abundance on Maculinea habitats, with the final aim of identifying the environmental variables determining patterns of variation in species composition in order to recommend a mowing regime that will promote our three target species: Maculinea teleius, M. nausithous and M. alcon. Experimental plots with different mowing regimes were established at eight sites in South-Eastern Germany, a region which still contains a number of relatively large, stable populations of these threatened butterfly species. Among the seven different ant species recorded, four belong to the genus Myrmica (M. scabrinodis, M. rubra, M. ruginodis and M. vandeli). Among these, M. scabrinodis results most abundant at all sites. In a CCA analysis of environmental variables recorded at the studied plots, ant species diversity appears largely determined by litter cover, mean temperature, and mean grass cover. Mowing once a year, in the second half of September, after the larvae have left their host plants, enhances the abundance of Myrmica ants in the meadows, and would be the best management compromise for all three species.  相似文献   

6.
白芨SSR引物筛选及群体遗传多样性研究   总被引:2,自引:0,他引:2  
黎君  杨恒  周天华 《西北植物学报》2016,36(7):1343-1350
白芨(Bletilla striata Rchb.)为中国珍稀濒危植物,重要的药用植物。该研究基于Illumina测序技术构建白芨基因组文库和微卫星文库,设计白芨微卫星引物,用白芨4个野生种群80个个体对引物进行多态性检测,应用4个白芨近缘种中进行引物的通用性检测,并在此基础上分析了白芨的遗传多样性和遗传分化,以探讨白芨的遗传结构和进化潜能。结果表明:(1)白芨基因组中微卫星片断丰富,共检测出17 841条微卫星片断。基于白芨微卫星库对100个位点设计了引物对,经PCR扩增和检测筛选出能够稳定扩增的多态性位点20个,每个位点的复等位基因数(Na)在2~6之间,平均为3.85;20对引物的大部分能够在4个白芨近缘种中成功扩增。(2)白芨在物种水平均有较高的遗传多样性(Na=3.85,I=1.07,H=0.614 7),白芨种群遗传分化强烈(Gst=0.43),居群间的基因流较弱(Nm=0.867 6),居群聚类分析结果均表明地理距离较近的居群具有较近的遗传关系。  相似文献   

7.
白及种质资源及其近缘种的SSR指纹图谱研究   总被引:1,自引:0,他引:1  
白及(Bletilla striata Rchb.)为中国珍稀濒危药用植物,野生资源枯竭,混伪种繁多。该研究基于SSR标记技术对16个地区48份白及(Bletilla striata Rchb.)样品和4份黄花白及(Bletilla ochracea Schltr.)、4份小白及(Bletilla formosana(Hayata)Schltr.)、4份华白及(Bletilla sinensis(Rolfe)Schltr.)样品进行遗传多样性分析,构建白及种质资源的SSR指纹图谱,并对60份白及样品进行种质资源鉴定,分析白及属种内及其种间的遗传分化特征。结果表明:(1)20对白及SSR引物均能在4个白及属植物中成功扩增,条带清晰且多态性丰富,每对引物的复等位基因数(Na)在4~9之间,等位基因数(Na)总和为127,平均为6.35。(2)筛选出基因型丰富、多态性信息含量(PIC)高的7对白及SSR引物(BJSSR01、BJSSR14、BJSSR15、BJSSR16、BJSSR18、BJSSR19、BJSSR22)构建的白及SSR指纹图谱能将白及属各种质资源清楚分开。(3)白及属在种间水平均有较高的遗传多样性(Na=6.35,I=1.429 1,h=0.706 8),物种间遗传分化强烈(Gst=0.44),物种间的基因流较弱(Nm=0.475 3)。(4)UPGMA聚类分析表明,60份供试样品明显聚为4大支,同一物种的个体首先聚在一起,这与形态学分类基本一致;不同来源地的样品种内和种间的亲缘关系有明显差异,地理距离较近的白及样品具有较近的遗传关系。  相似文献   

8.
福建省2种木本植物新记录   总被引:1,自引:0,他引:1  
通过2017~2018年对福建省本土植物进行野外调查,发现2种木本植物新记录:薄叶红厚壳(Calophyllum membranaceum Gardn. & Champ.)和光叶紫玉盘(Uvaria boniana Finet&Gagnep.)。薄叶红厚壳为藤黄科(Calophyllaceae)红厚壳属(Calophyllum)植物,该属为福建省新记录属;光叶紫玉盘为福建省番荔枝科(Annonaceae)紫玉盘属(Uvaria)新记录种。现予以报道,并提供相应照片及描述,此次报道丰富了福建省本土木本植物资源,凭证标本存放于福建农林大学林学院植物标本馆。  相似文献   

9.
Aspects of the life cycle of the hydroid Sertularia cupressina were monitored over a period of 2 y using settlement panels. The reproductive period, determined by the presence of acrocysts and larval settlement, was November to January. Recently settled hydroids were more abundant on horizontal upward facing surfaces than on horizontal downward facing or vertical surfaces. The spatial dispersal of settlers was random. S. cupressina was a conspicuous and persistent component of fouling communities developing on both upward facing and vertical panels over 2 y. Following settlement in winter 1979–80, hydrocauli reached their greatest height between November 1980 and April 1981, but fouling and breakage of stems occurred during spring 1981. Regeneration from the tips of broken stems and from hydrorhizae occurred in June and July 1981.  相似文献   

10.
台湾坡天牛一般随着木制品及包装制品进行远距离传播入境。目前我国台湾地区和日本有分布,在我国大陆地区尚未见该虫的发生报道。2019年5月凭祥口岸从来自越南的相思木板上截获了台湾坡天牛,为我国大陆首次截获。通过显微形态特征的观察和测量进行台湾坡天牛种类鉴定。台湾坡天牛与近似种的主要区别:其鞘翅基部具明显的黑褐色宽横带。通过入侵可能性分析,来自我国台湾地区、日本的台湾坡天牛入侵我国大陆地区的可能性很大。台湾坡天牛在我国广东、广西、福建等地区定殖和扩散风险很大。一旦传入我国,将对我国的农林安全造成巨大威胁,各口岸应对进境的木制品及包装加强检验检疫。  相似文献   

11.
A total of 1,302 parasitoids representing 8 species and 4 families were recovered from 9,818 fruit fly host fruits sampled. The most common parasitoid species wasDiachasmimorpha longicaudata (Ashmead). Average percent parasitism ranged between 0.44 and 29.23%. Parasitoid emergence data indicate thatAnastrepha ludens (Loew),A. obliqua (Sein),A. serpentina (Wiedeman),A. striata (Schiner) andToxotrypana curvicauda (Gerstaecker) were subject to parasitism. We provide information on the population fluctuation ofAnastrepha ludens, A. obliqua, A. serpentina, A. distincta (Greene),A. striata, A. fraterculus (Wiedeman),A. chiclayae (Greene),A. montei (Costa Lima),A. leptozona (Hendel) andA. tripunctata (Wulp).Anastrepha ludens andA. obliqua were the most common species, representing 95.3% of all fruit fly species caught in McPhail traps.   相似文献   

12.
An insecticide exclusion method was used to evaluate the effect of parasitoids on level of infestation by the stem borers, Busseola fusca (Fuller) and Chilo partellus (Swinhoe), in grain sorghum. In field trials conducted at Brits and at Delmas, South Africa, a selective organophosphate insecticide, dimethoate, was applied twice weekly at each site to three subplots whereas three other identical subplots served as controls. Twelve plants were randomly selected from each subplot at weekly intervals and removed from the field. In the laboratory all plants were dissected to record borer infestation. In order to determine parasitism levels egg batches were kept in Petri dishes and all borer larvae and pupae were kept individually in vials until either parasitoids or moths emerged. At Brits ca. 97% of borers were C. partellus and 3% B. fusca, whereas at Delmas 37.5% were C. partellus and 62.5% B. fusca. The most abundant parasitoids of B. fusca were Cotesia sesamiae (Cameron) and Bracon sesamiae Cameron. The dominant parasitoids of C. partellus at both sites were C. sesamiae, Stenobracon spec., Dentichasmias busseolae Henrich and Pediobius furvus (Gahan). No egg parasitoids were found. At both sites, infestation levels in the sprayed plots were significantly higher than in the untreated plots. On the other hand, parasitism levels of borers in the unsprayed plots were significantly higher than in the treated plots. It was concluded that the higher infestation level of sorghum by stem borers in the sprayed plots was because of partial elimination of parasitoids and possibly other natural enemies by the pesticide.  相似文献   

13.
A survey of black scaleSaissetia oleae (Olivier) parasitoids present in southern California was conducted between September 1987 and September 1989. From 308 collections of black scale-infested citrus, olive, and oleander twigs from 19 sites in southern California, 1,610 specimens were collected. Nine primary and six secondary parasitoid species were identified. Four primary species were abundant in southern California:Metaphycus bartletti Annecke & Mynhardt,M. helvolus (Compere),Scutellista caerulea (Fonscolombe) (=S. cyanea Motschulsky), andDiversinervus elegans Silvestri. The most common secondary parasitoids wereMarietta mexicana (Howard),Cheiloneurus noxius Compere, andTetrastichus minutus (Howard). In the coastal region of southern California,M. bartletti was the most abundant parasitoid, followed in order byD. elegans, S. Caerulea, andM. helvolus. In the intermediate and interior regions,M. helvolus was most abundant.D. elegans was second most abundant in the intermediate region, but was rare in the interior region.M. bartletti was second in abundance in the interior region and third in the intermediate region.   相似文献   

14.
Contribution of leaf surface fungi to the air spora   总被引:1,自引:0,他引:1  
High concentrations of airborne fungal spores frequently occur from spring through fall in temperate areas of the world. Although it is generally assumed that fungi on leaf surfaces are contributors to the air spora, little data are available comparing the types of fungi found on leaf surfaces with those in the atmosphere. Air sampling was carried out with a Burkard Spore Trap located on the roof of a building on the University of Tulsa campus using standard methods. Leaf samples were aseptically collected from Ulmus americana and Quercus palustris trees on campus, placed in sterile plastic bags, and brought to the lab. For each leaf, 4 cm2 areas of both upper and lower leaf surfaces were swabbed and plated on malt extract agar with streptomycin. Cultures were incubated at room temperature for 5–7 days and then examined microscopically. Results were expressed as colony forming units (CFU)/cm2. Twenty-one fungal taxa were identified from the air samples. The most abundant taxa were Cladosporium, ascospores, basidiospores, and Alternaria; together these four spore types comprised over 90% of the yearly total. Yeasts were the most abundant fungi isolated from both leaf types. Among the mycelial fungi were Phoma species, followed by Cladosporium and Alternaria. Overall twenty genera of filamentous fungi were identified. Yeasts and Phoma are normally splash dispersed and were not identified in the Burkard air samples. However, 10 taxa isolated from leaf surfaces were registered in air samples. Crude estimates of the leaf surface area of each tree suggest that the total fungal load was approximately 5.04×108 CFU for Ulmus and 2.71×108 CFU for Quercus. Of these levels, 19% were from fungi also detected in air samples. The data suggest that some leaf-surface fungi are major contributors to the air spora.  相似文献   

15.
The striata complex, a group of spined loaches included in the genus Cobitis and characterized by a striped coloration pattern on the lateral midline, is distributed in rivers in northeastern Asia to western Japan. The complex comprises 2 continental species (Cobitis tetralineata and Cobitis lutheri) and 3 Japanese races of species rank (large race, middle race, and small race), the small race further comprising 6 local forms of subspecific rank (Tokai form, Biwa form, Yodo form, Sanyo form, San-in form, and Kyushu form). Previous karyological studies have revealed that the large race is an allotetraploid, the others being diploid. In this study, mitochondrial (mt) DNA analyses were conducted for 30 diploid populations of the Cobitis striata complex from Japan and Korea to examine: (1) their phylogenetic relationships and the position of the complex among the major lineages of Cobitis; and (2) the genetic relationships among the Japanese and Korean populations. The results, based on cytochrome b sequences (724 base pairs) analyzed with those of the main lineage of European and Japanese Cobitis, indicated that the striata complex should be considered as a monophyletic group, which evolved in northeastern Asia. Initially considered as a subspecies of Cobitis taenia, widely distributed from Europe to Asia, the striata complex does not have a sister-relationship with the former. Although the Korean species C. tetralineata was formerly believed to be closely related to the middle race in Japan, and a second continental species, C. lutheri, closely related to the Kyushu or San-in forms of the small race in Japan, the trees resulting from the present study revealed that the two Korean species were clustered with each other and separated from all Japanese races.  相似文献   

16.
在海南省会山省级自然保护区的野外考察中,发现双唇兰属中国一新记录种:条纹双唇兰(Didymoplexis striata J.J. Sm.)。条纹双唇兰具有以下特征,与该属的其他种区分:花被筒内侧具纵向的浅褐色条纹,唇瓣中间具扁平的淡黄色加厚,由唇瓣先端一直延伸至唇瓣基部。  相似文献   

17.
David W. Langor 《BioControl》1991,36(2):303-313
Fifty-four species of insects, 5 of spiders, 5 of mites, 1 harvestman and 1 nematode co-occurred with the eastern larch beetle,Dendroctonus simplex LeConte, on tamarack,Larix laricina (Du Roi) K. Koch, at 2 localities in Newfoundland. The most abundant predators were the flyMedetera gaspensis Bickel and the beetleRhizophagus dimidiatus Mannerheim and the most abundant parasitoids were the HymenopteraSpathius canadensis Ashmead,Rhopalicus tutela (Walker) andRoptrocerus xylophagorum (Ratzburg).D. simplex is recorded as a new host for 9 predator and 3 parasitoid species.   相似文献   

18.
为揭示白及与黄花白及内生菌群落特征异同的内在机制,该文运用末端限制性酶切片段长度多态性分析技术对白及和黄花白及叶、茎、块茎、根等组织中内生细菌16S rDNA、内生真菌ITS区进行检测,分析内生菌丰度及多样性指数,运用主成分分析、聚类分析和相关性分析对比白及与黄花白及内生菌差异.结果表明:(1)白及和黄花白及各组织内生...  相似文献   

19.
Competition among six wood decay fungi was studied using 15×15 mm wood blocks placed in 250×250 mm plastic trays filled with unsterilized sand or clay. The wood blocks were preinoculated with Heterobasidion annosum (Fr.) Bref., Resinicium bicolor (Alb. & Schw. ex Fr.) Parm., Phanerochaete sanguinea (Fr.) Hjortstam, Coniophora sp. DC. ex Me"rat, Armillaria borealis Marxmuller and Korhonen and Hypholoma capnoides (Fr.) Kummer before they were combined in all possible combinations in the trays. Two methods were used, one with all wood blocks inoculated, and one with sterilized non-inoculated wood blocks distributed between the inoculated ones. Wood blocks preinoculated with the six species were also used in a pairwise competition test. Following incubation for 9 months in darkness at 21°C, mycelia were reisolated and identified. R. bicolor was most successful at invading through the soil and replacing other species in the wood blocks. P. sanguinea, Coniophora sp. and H. capnoides also had some success.  相似文献   

20.
该研究以新疆的地图衣科(Rhizocarpaceae)地图衣属(Rhizocarpon)100余份地衣标本为材料,通过形态解剖学观察、化学成分分析及分子学鉴定的方法了解新疆地图衣属地衣的物种多样性。结果表明:(1)鉴定出7种地图衣属地衣,包括1个中国新记录种,命名为淡黄色地图衣(R.atroflavescens),6个常见种分别是黑红地图衣(R.badioatrum)、灰地图衣(R.disporum)、双孢地图衣(R.geminatum)、地图衣(R.geographicum)、巨地图衣(R.grande)和岩表地图衣(R.superficiale)。(2)编制了新疆22种地图衣属地衣的分种检索表。(3)系统发育分析结果表明,新疆地图衣属地衣的分子鉴定与形态解剖特征结果一致,更准确地证明淡黄色地图衣为中国新记录种。(4)对已报道的新疆22种地图衣属地衣的地区分布及海拔分布统计显示,新疆22种地图衣属地衣在世界各地均有分布,其中亚洲分布最丰富;该22种地图衣属地衣从低海拔到高海拔都有分布,且各海拔高度物种分布不均匀,总体在高海拔地区分布的物种较多。  相似文献   

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