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1.
Three new Longidorus species from Slovakia are described. Longidorus carpathicus n. sp. most closely resembles Longidorus silvae but differs by having a longer odontostyle, odontophore, and total stylet; smaller a and c ratios; and longer distance to the guide ring. This new species also resembles L. picenus, L. macrosoma, and L. major but differs by having a narrower lip width. It further differs from L. picenus by having a longer odontostyle and smaller c ratio, and by lacking males; from L. macrosoma by having a longer odontostyle, smaller c ratio, by lacking males, and a more pronounced J1 tail peg; and from L. major by having a shorter body length, longer odontostyle, longer odontophore, and longer J1 tail peg. Longidorus piceicola n. sp. most closely resembles L. eridanicus, from which it differs by having a greater lip width, longer tail, smaller c ratio, larger c'' ratio, shorter hyaline tail length, and a conically rounded vs. hemispherical tail. This new species differs from L. cylindricaudatus by having a larger lip width, longer odontostyle and odontophore, and a greater distance to the guide ring; from L. nevesi by having a shorter body length, longer odontostyle, larger c'' ratio, and shorter hyaline tail length. Longidorus juglansicola n. sp. most closely resembles L. athesinus but differs by its longer body, wider lips, and larger a and c ratios. It closely resembles L. vineacola but differs by its shorter body length, smaller c ratio, and an almost parallel lip outline vs. an expanded lip outline; from L. lusitanicus by a longer odontophore and tail, and an almost parallel lip outline vs. an expanded lip outline.  相似文献   

2.
Bacidia neosquamulosaAptroot & van Herk, a new corticolous lichen species, is described from the Netherlands, where it seems to be rapidly spreading and where it is considered to be a neophytic species. It is also reported from Belgium and Great Britain. It resembles corticolous morphs of the rather variableB. arnoldiana, but differs from this and other species by the longer, conspicuously septate, filiform, curved, macroconidia, the longer ascospores and the squamulose-isidiate thallus.  相似文献   

3.
Bradya typica Boeck, 1873 is described from samples collected in the course of a colonisation experiment in Kongsfjorden, Spitsbergen (2003–2005). The male of B. typica, the type-species of the genus is described for the first time. B. typica can be distinguished from its congeners by its caudal rami (1.4 times longer than wide) and by its P5 (exopod longer than wide, inner terminal seta of exopod longest, inner seta of baseoendopod longer than outer one and surface seta rigid and curved). Variability within the species is rather small as only the length of some setae is slightly different. B. cladiofera Lang, 1965, B. congenera Sars, 1920, B. minutiseta Soyer, 1973 and B. pugiochaeta Arlt, 1983 are closely related to B. typica. Some details of the morphology, such as the body ornamentation and the longer hair-like pinnules on the spines of the swimming legs, are very difficult to observe even with maximum magnification. With certainty, B. typica is distributed near the Norwegian coast (Oslo Fjord to Trondheim Fjord), the Swedish coast (Skagerak to Öresund), around Spitsbergen and around the polar islands north of Grinnelland (Canadian Arctic Archipelago near Baffin Bay). Records of B. typica from the Kara Sea (near Novaya Zemlya), near Franz Joseph Land, Iceland, Greenland, the British Isles and from deep waters of the North Sea have to be confirmed.  相似文献   

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5.
用18S rDNA基因序列分析饶氏藻属(Jaoa)与相关藻类的亲缘关系。结果表明:饶氏藻18S rDNA的长度为1632 bp,GC%为50.6%,泡状饶氏藻18S rDNA的长度为1639 bp,GC%为50.3%。用最大简约法与饶氏藻上一级分类单元(目)构建的系统树表明有4个大的分支。两种饶氏藻与石莼目的 Ulva curvata、U.rigida、Enteromorpha intestinalis和Monostroma grevillei构成很强的支持分支(分支B),它们之间的核苷酸趋异性最低仅0.041,而与胶毛藻目的 Chaetophora incrassata的趋异性则很显著,达0.112,因此,饶氏藻应属于石莼目的一个类群,且饶氏藻和泡状饶氏藻构成一单系起源的分支,这两个物种的趋异性仅0.002,显示出它们具有非常紧密的亲缘关系,很可能是1种1变种而不是2种。  相似文献   

6.
Spore-forming microbes recovered from spacecraft surfaces and assembly facilities were exposed to simulated Martian UV irradiation. The effects of UVA (315 to 400 nm), UVA+B (280 to 400 nm), and the full UV spectrum (200 to 400 nm) on the survival of microorganisms were studied at UV intensities expected to strike the surfaces of Mars. Microbial species isolated from the surfaces of several spacecraft, including Mars Odyssey, X-2000 (avionics), and the International Space Station, and their assembly facilities were identified using 16S rRNA gene sequencing. Forty-three Bacillus spore lines were screened, and 19 isolates showed resistance to UVC irradiation (200 to 280 nm) after exposure to 1,000 J m−2 of UVC irradiation at 254 nm using a low-pressure mercury lamp. Spores of Bacillus species isolated from spacecraft-associated surfaces were more resistant than a standard dosimetric strain, Bacillus subtilis 168. In addition, the exposure time required for UVA+B irradiation to reduce the viable spore numbers by 90% was 35-fold longer than the exposure time required for the full UV spectrum to do this, confirming that UVC is the primary biocidal bandwidth. Among the Bacillus species tested, spores of a Bacillus pumilus strain showed the greatest resistance to all three UV bandwidths, as well as the total spectrum. The resistance to simulated Mars UV irradiation was strain specific; B. pumilus SAFR-032 exhibited greater resistance than all other strains tested. The isolation of organisms like B. pumilus SAFR-032 and the greater survival of this organism (sixfold) than of the standard dosimetric strains should be considered when the sanitation capabilities of UV irradiation are determined.  相似文献   

7.
8.
《Comptes Rendus Palevol》2003,2(4):269-279
Kromdraai B, situated less than 2 km east of Sterkfontein, in the Gauteng province of South Africa, has yielded 27 specimens, attributed to a single Plio-Pleistocene hominid species, including the type specimen of Paranthropus (Australopithecus) robustus. By using resampling and morphological analysis, and after considering the most diagnostic features that have been used in the past for the lower dentition, we here suggest that one specimen from Kromdraai B, KB 5223, is clearly distinct from P. robustus and represents early Homo. To cite this article: J. Braga, J.F. Thackeray, C. R. Palevol 2 (2003).  相似文献   

9.
Information on the genus Harmonicon F.O.P.-Cambridge, 1896, a key to the species and a new diagnosis differing from the one in Maréchal and Marty (1998) are provided. A new species is described: Harmonicon oiapoqueae differing from other species of the genus by the morphology of the posterior sternal sigilla, the more recurved, inverted U–shaped fovea, the amount and arrangement of maxillary cuspules, a single row of teeth on the claws of the palpal tarsus, longer and more slender legs III and IV in females, longer embolus, thinner bulb, and longer, more slender legs in males. The status of the putative junior synonyms of Harmonicon, Pseudohermachura Mello-Leitão, 1927 and Prosharmonicon Mello-Leitão, as well as the two species formerly assigned to Harmonicon, Harmonicon nigridorsi Mello-Leitão, 1924 and Harmonicon riveti Simon, 1903, is discussed.  相似文献   

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11.
Bacterial infections of the lungs of cystic fibrosis (CF) patients cause major complications in the treatment of this common genetic disease. Burkholderia cenocepacia infection is particularly problematic since this organism has high levels of antibiotic resistance, making it difficult to eradicate; the resulting chronic infections are associated with severe declines in lung function and increased mortality rates. B. cenocepacia strain J2315 was isolated from a CF patient and is a member of the epidemic ET12 lineage that originated in Canada or the United Kingdom and spread to Europe. The 8.06-Mb genome of this highly transmissible pathogen comprises three circular chromosomes and a plasmid and encodes a broad array of functions typical of this metabolically versatile genus, as well as numerous virulence and drug resistance functions. Although B. cenocepacia strains can be isolated from soil and can be pathogenic to both plants and man, J2315 is representative of a lineage of B. cenocepacia rarely isolated from the environment and which spreads between CF patients. Comparative analysis revealed that ca. 21% of the genome is unique in comparison to other strains of B. cenocepacia, highlighting the genomic plasticity of this species. Pseudogenes in virulence determinants suggest that the pathogenic response of J2315 may have been recently selected to promote persistence in the CF lung. The J2315 genome contains evidence that its unique and highly adapted genetic content has played a significant role in its success as an epidemic CF pathogen.  相似文献   

12.
The genusJaegeria consists of a diploid-polyploid complex of eight species found in moist habitats from Mexico to South America. The distributions, habitats, generic affinities, and tribal placement are discussed. Chromosome numbers were determined for all species exceptJ. axillaris, which is known only from Colombia.J. glabra andJ. pedunculata are diploid (2n = 18) ;J. hirta, J. macrocephala, J. gracilis, andJ. crassa are tetraploid (2n = 36) ;J. bellidiflora is octoploid (2n = 72). One Galápagos Island endemic,J. gracilis, is quite similar to the common mainland species,J. hirta, but the other endemic,J. crassa, is quite distinct from any other species.J. bellidijlora is most similar morphologically toJ. glabra;J. macrocephala is allied toJ. pedunculata. J. axillaris is somewhat distinct from the other species.  相似文献   

13.
The aim of the present study is to elucidate if Oxyporus philadelphi (Parmasto) Ryvarden and Botryodontia millavensis (Bourdot & Galzin) Duhem & H. Michel are conspecific, as suggested by their similar morphology. The analysis of ribosomal DNA ITS sequences indicate that the specimens of O. philadelphi and B. millavensis belong to a single species. The species is closely related to the type species (B. cirrata) of the genus Botryodontia, and therefore the name B. millavensis should currently be used for this taxon. Botryodontia millavensis grows on a wide selection of host species—Juniperus communis, Philadelphus coronarius, Picea abies, Fraxinus excelsior, Lonicera sp., J. turcomanica—and is distributed widely in temperate Eurasia.  相似文献   

14.
描述了四川夹江(兰科)石斛属植物一新种,即夹江石斛。  相似文献   

15.
描述了四川(唇形科)鼠尾草属植物一新种,即川西鼠尾草。新植物毛被与花冠管内被长柔毛而独特,接近于粘毛鼠尾草(Salvia roborowskii Maxim.),其区别在于多年生草本,根粗壮,直径1~2 cm;花萼较长,长1~1.2 cm;花冠较长,长约2.1 cm,内面离花冠筒基部约2 mm处,向上长约5 mm一段全被长柔毛(非毛环),花冠筒近中部向上近直弯曲而逐渐扩大,冠檐上下唇具紫红色斑点。  相似文献   

16.
The evolutionary pathway of Palinuridae (Crustacea, Decapoda) is still controversial, uncertain and unexplored, expecially from a karyological point of view. Here we describe the South African spiny lobster Jasus lalandii karyotype: n and 2n values, heterochromatin distribution, nucleolar organizer region (NOR) location and telomeric repeat structure and location. To compare the genomic and chromosomal organization in Palinuridae we located NORs in Panulirus regius, Palinurus gilchristi and Palinurus mauritanicus: all species showed multiple NORs. In J. lalandii NORs were located on three chromosome pairs, with interindividual polymorphism. In P. regius and in the two Palinurus species NORs were located on two chromosome pairs. In the two last species 45S ribosomal gene loci were also found on B chromosomes. In addition, the nature and location of telomeric repeats were investigated by FISH in J. lalandii, P. gilchristi, P. mauritanicus Palinurus elephas, and P. regius (Palinuridae, Achelata), and in Scyllarus arctus (Scyllaridae, Achelata): all these Achelata species showed the (TTAGG)n pentameric repeats. Furthermore, in J. lalandii these repeats occurred in all the telomeres and in some interstitial chromosomal sites, associated with NORs.  相似文献   

17.
The phylogeny of the three species that comprise the genus Betaphycus Doty in Silva, Basson and Moe and their phylogenetic relationships with other eucheumatoids are still unresolved. In this study, the utility of the mitochondrial cytochrome oxidase I (COI) marker in resolving their relationships was evaluated. Analyses of the COI sequences from Betaphycus philippinensis Doty and Betaphycus speciosus (Sonder) Doty ex Silva specimens collected from their type localities (Sorsogon, Philippines and Western Australia, respectively) revealed that the two species formed a well-supported clade distinct from Eucheuma J. Agardh and Kappaphycus Doty ex Silva. The genotyped specimens of B. philippinensis were observed to exhibit dorsal protuberances, a characteristic which has been regarded as a key diagnostic feature of Betaphycus gelatinus (Esper) Doty ex Silva. This observation raised the possibility that these two taxa are conspecific. In addition, B. philippinensis specimens were also observed to exhibit morphological features that could be used to distinguish the species from other eucheumatoids, such as the location tetrasporangial nemathecium in the thallus and the presence of apical or lateral pit connections in the tetraspores. The species referred to in the literature as “B. gelatinus” (as Eucheuma gelatinae) collected from northwestern Philippines was identified as a species of Eucheuma based on molecular and morphological evidence. The phylogenetic relationships of this species with other related eucheumatoid taxa were also determined.  相似文献   

18.
Host-handling behaviors of Eretmocerus mundus (Mercet) (Hymenoptera: Aphelinidae) toward first to fourth instar nymphs of the Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) B and Q biotypes and of Trialeurodes vaporariorum (Westwood) (Homoptera: Aleyrodidae) were compared under laboratory conditions. The host acceptance rates differed among host stages but not among host species or biotypes. In all host species and biotypes, the parasitoids stopped their host-handling behavior before oviposition more often with older hosts. The total host-handling time was longer for the fourth instars than for younger instars, mainly due to the longer oviposition times and probing times. E. mundus showed marking behavior for the B. tabaci B and Q biotypes, but not for T. vaporariorum. In conclusion, E. mundus could parasitize all whitefly biotypes and species used in this study, but both B. tabaci biotypes were more suitable hosts than T. vaporariorum. The younger instars were good oviposition targets in all hosts.  相似文献   

19.
The unusual disjunct distribution of the yellow-flowered, radiate, Northern Cape endemic Emilia hantamensis J.C.Manning & Goldblatt, relative to the other Emilia species in southern Africa, prompted investigation into its phylogenetic position and relationships. Phylogenies based on the ITS and trnL–trnF regions reveal that it is not a member of the genus Emilia but belongs in a well-supported clade with Bolandia, a genus comprising five species mainly from the Western and Northern Cape, and the monotypic genera Stilpnogyne and Mesogramma. It is placed sister to Bolandia and its cypselas match those of Bolandia in shape, colour and indumentum, except for a distinct ridge of hairs on the inner rib of the ray cypselas. It is further distinguished from Bolandia by its annual habit and conical disc floret style apices and obtuse to rounded ray floret style apices. It is recognised and described here as a new monotypic genus, Bertilia Cron with the single species B. hantamensis (J.C.Manning & Goldblatt) Cron.  相似文献   

20.
Brachydorus swarupi sp. n. is described from soil about roots of arecanut palm in Kerala State, India. It is the second species to be described in Brachydorus De Guiran and Germani 1968 and differs from B. tenuis, the type species, by its greater length (1.52-2.34 mm for B. swarupi vs. 1.03-1.32 mm for B. tenuis); longer and more delicate stylet (26-35 μm for B. swarupi vs. 20-23 μm for B. tenuis); head shape with concave protrusion at oral aperture (simple rounded in B. tenuis); shorter isthmus and larger posterior bulb in B. swarupi; shorter tail (in B. tenuis c = 9.7 [8.6-11.5] in female, c = 42.3 [33-48] in male); larger spicules and gubernaculum (22-39 μm and 9 -1 2 μm, respectively, for B. tenuis); and phasmids near posterior connection of caudalalae and tail (almost central on caudalalae of B. tenuis). The relationship of Brachydorus to Dolichodorus is discussed.  相似文献   

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