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1.
Soldanella contains 16 species of herbaceous perennials that are endemic to the central and south European high mountains. The genus is ecogeographically subdivided into forest/montane and alpine species. Evolutionary relationships and large-scale biogeographic patterns were inferred from parsimony analyses of the internal transcribed spacer (ITS) regions of nuclear ribosomal DNA, and genetic distance analyses based on amplified fragment length polymorphism (AFLP) markers. The ITS region proved useful for examining subgeneric relationships and testing hypotheses on genus-wide divergence times, whereas the AFLP markers were suitable for studying relationships among closely related taxa and biogeographic patterns of divergence. Neither ITS nor AFLP data supported sectional delimitations, particularly those related to the grouping of S. alpina (sect. Soldanella) with S. pusilla (sect. Tubiflores), which may be the result of hybridization. Additional results and conclusions drawn are (1) Soldanella is derived from an ancestor of Asian origin with a montane ecology; (2) estimates of divergence times suggest a late Quaternary origin of the genus; (3) alpine species of sect. Tubiflores diverged from within a paraphyletic sect. Soldanella of mainly montane species; (4) alpine and montane species of Soldanella experienced different cycles of range expansion and contraction during late Quaternary climatic changes, resulting in differential patterns of geographic distribution; and (5) AFLP divergence among montane species from eastern Europe was lower than between alpine species; we hypothesize that the latter differentiated in allopatric regions of expansion during glacials, while the former experienced secondary contact at lower elevations in more southern refugia.  相似文献   

2.
RAPD analysis has been performed for 15 plant populations, covering eight different infraspecific taxa of Sideritis pusilla (Lange) Pau, member of the Lamiaceae endemic to southeastern Spain, and their putative parental species Sideritis hirsuta L. and Sideritis Uucantha Cav. Genetic distances, together with the presence of numerous fixed molecular markers differentiating S. pusilla from its putative ancestors, indicate that it should be considered as a true species. Cladistic and populational analysis led to the allocation of S. pusilla populations into three major groups– osteoxylla, jlavovirens and pusilla/almeriensis –which include taxa previously described as ranging from the varietal to the specific level. Low genetic differentiation among groups revealed by a reduced number of specific molecular markers justify their assignment under the infraspecific range. Moreover, the existence of both morphological and biogeographical differences, supports a status for these groups as subspecies of S. pusilla. Highly significant ( P <0.002) variance partitioning data (AMOVA) extracted from the analysis of individuals within S. pusilla populations show that, of the total genetic diversity, 68.8% was attributable to individual differences within populations, 19.9% to populational differences within groups, and only 11.3% to divergence between groups. This distribution is in agreement with the outcrossing nature of these plants. Comparative analysis of variance within populations reveals a reduced genetic variation for the osteoxylla group, thus supporting its previous consideration as an endangered taxon.  相似文献   

3.
The hitherto unknown males of Paregnatius salavatiani, Paraconophyma pusilla, Wiltshirella fusiformis and Lyrotyloides viridis are described, and a new genus of Egnatiinae is erected for P. pusilla.  相似文献   

4.
The structural properties of the hemocyanin isolated from the Mediterranean mud shrimp, Upogebia pusilla (Decapoda: Thalassinidea), were investigated. Our intent was to make use of the U. pusilla case to perform a structural comparison between crustacean and chelicerate 4x6-meric hemocyanins. The thalassinidean hemocyanin appears similar in size but different in structural organization compared to the chelicerate 4x6-mer. Ultracentrifuge analyses on the purified protein revealed a sedimentation coefficient of 39S, typical of 4x6 hemocyanins. Electron micrographs are in agreement with a model in which four 2x6-meric building blocks are arranged in a tetrahedron-like quaternary structure and not in the quasi-square-planar orientation characteristic of the chelicerate protein. Size-exclusion chromatography-fast protein chromatography analysis showed elevated instability of the protein in absence of divalent ions or at pH values higher than 8.0. This analysis also shows that the dissociation of the U. pusilla 4x6-meric hemocyanin into hexamers occurs without any intermediate 2x6-meric state, in contrast with the dissociation profile of the chelicerate protein exhibiting several dissociation intermediates. The oxygen-binding properties of U. pusilla hemocyanin were studied to disclose possible effects by the typical allosteric effectors that modulate the functional properties of crustacean hemocyanin. A marked Bohr and lactate effect, but no significant influence of urate, on the oxygen affinity of U. pusilla hemocyanin were found.  相似文献   

5.
Aplectana tucumanensis n. sp., from the large intestine of Amphisbaena bolivica, is described and illustrated. Of the 43 nominal species of Aplectana, A. tucumanensis n. sp. represents the fourth species reported in Amphisbaena spp. These 4 species are separated on the basis of male characters: spicules of Aplectana alba approximately 60 micro in length, Aplectana pusilla and A. tucumanensis approximately 100 micro, Aplectana raillieti greater than 230 micro; papillae pattern of A. pusilla with 3 preanal pairs, 2 adanal pairs, 6 postanal pairs, and 1 median papilla compared to 9 preanal pairs, 1 adanal pair, 6 postanal, and no median papilla for A. tucumanensis.  相似文献   

6.
Bacteria-free cultures of the prasinophyte Micromonas pusilla (Butcher) Monton and Parke, UTEX LB 991, were produced by intially determining the effects of several antibiotics on the growth of this alga and then using a combination of these antibiotics to eliminate associated bacteria, Micrononas pusilla was resistant ot penicillin G, neomycin, gentamicin and streptomycin at bactericidal concentrations but sensitive to chloramphenicol and polymixin B. Passage of M. pusilla through the sequence of antibioties penicillin G → neomycin → gentamician → kanamycin resulted in an axenic culture of M, pusilla this method should be suitable for producing axenic culture of other strains of M. pusilla.  相似文献   

7.
Rhodopsis pusilla Bush 1905. a minute species characterized by a chitinous opereular plate bearing numerous spines is redescribed and a neotype is designated. Apomatolos Uchida. 1978 is synonymized with Rhodopsis . Ventral fillform mouth-palps are present a rarely observed character in common with Pseudovermilia Bush. Variability between and within populations from different seas is discussed. Rhodopsis pusilla from Heron Island shows opercular dimorphism. Pouch-like brood chambers similar in texture (SEM) to the Rhodopsis tubes and integrally associated with rings marking successive position of the peristome were found on some tubes. These brood chambers. presumed to belong to Rhodopsis are described with conjectures as to their mode of formation. Some aspects of opercular polymorphism in serpulids are discussed.  相似文献   

8.
Six closely related taxa of the sect.Eusideritis of the genusSideritis (S. leucantha, S. pusilla, S. flavovirens, S. granatensis, S. biflora andS. osteoxylla) are analysed to elucidate their phylogenetic relationships and position within the sect.Eusideritis. Meiotic behaviour, karyotype features, size and fertility of pollen grains, DNA amounts and seed protein profiles are reviewed. A polyploid origin of the group (from x = 7) and the further diversification through dysploidy and chromosome repatterning is postulated.S. osteoxylla is apparently of hybrid origin.  相似文献   

9.
We have studied karyofonds of natural populations and B-chromosome morphology of 8 species of blackflies from the North-Western region of Russia: Odagmia ornata Mg., Hellichiella crassa Rubz., Simulium morsitans Edw., Simulium argyreatum Mg., Shoenbaueria pusilla Fries., Cnetha fontinalis Radzv., Stegopterna duo-decimata Rubz., and Archesimulium tuberosum Lundstr. For this purpose we made slides of squashed blackflies larvae with salivary gland polytene chromosomes stained by aceto-orcein, in addition to similarly stained slides with mitotic chromosomes from gonads and ganglia. Morphology of polytene B-chromosomes of Shoenbaueria pusilla Fries., Cnetha fontinalis Radzv., Stegopterna duodecimata Rubz., and Archesimulium tuberosum Lundstr. has been first described. B-chromosome polymorphism was found in all species, but the number of B chromosomes was conserved within each differences in polytene individual. Stable and distinct interspecific differences in the morphology of polytene B-chromosomes were demonstrated, and these characters are advisable to use to distinguish the species. We have investigated for the first time karyofonds of Od. ornata populations from Arkhangelsk Region (Solovetskie Islands) and Leningrad Region (railway station Sablino), and those of S. argyreatum populations from Murmansk Region (Kandalaksha environs) and Karelia (railway station Chupa). A long term study of Od. ornata and S. argyrestum population from North-Western Russia revealed interspecific and interpopulation dynamics of the occurrence of specimens with B-chromosomes. Some populations showed an increased percentage of individuals with B-chromosomes. It is suggested that B-chromosomes may play a role in adaptation of polulations to severe environmental conditions.  相似文献   

10.
The bacterial endosymbionts of two species of the bivalve genus Solemya from the Pacific Ocean, Solemya terraeregina and Solemya pusilla, were characterized. Prokaryotic cells resembling gram-negative bacteria were observed in the gills of both host species by transmission electron microscopy. The ultrastructure of the symbiosis in both host species is remarkably similar to that of all previously described Solemya spp. By using sequence data from 16S rRNA, the identity and evolutionary origins of the S. terraeregina and S. pusilla symbionts were also determined. Direct sequencing of PCR-amplified products from host gill DNA with primers specific for Bacteria 16S rRNA genes gave a single, unambiguous sequence for each of the two symbiont species. In situ hybridization with symbiont-specific oligonucleotide probes confirmed that these gene sequences belong to the bacteria residing in the hosts gills. Phylogenetic analyses of the 16S rRNA gene sequences by both distance and parsimony methods identify the S. terraeregina and S. pusilla symbionts as members of the gamma subdivision of the Proteobacteria. In contrast to symbionts of other bivalve families, which appear to be monophyletic, the S. terraeregina and S. pusilla symbionts share a more recent common ancestry with bacteria associating endosymbiotically with bivalves of the superfamily Lucinacea than with other Solemya symbionts (host species S. velum, S. occidentalis, and S. reidi). Overall, the 16S rRNA gene sequence data suggest that the symbionts of Solemya hosts represent at least two distinct bacterial lineages within the gamma-Proteobacteria. While it is increasingly clear that all extant species of Solemya live in symbiosis with specific bacteria, the associations appear to have multiple evolutionary origins.  相似文献   

11.
Scorzonera pusilla is one of the early-spring short- lived perennial desert plants. Non-dormant seeds of S. pusilla are very small and light , and able to absorb water very quickly . Suitable temperature for germination was between 0℃ and 15℃, and the optimum temperature was 4℃ . With the increasing temperature, the germination percentage decreased evidently. Especially , temperature fluctuations had not significant effect on seed germination. Final germination percentages decreased distinctly with decreasing water potential of PEG and NaCl solution. The relationship between water potential of different solutions and germination was negative. The stronger the osmotic stress was, the more the proline content of seedlings was. The effects of NaCl on germination and seedlings were much stronger than that of iso-osmotic PEG in spite of two different temperatures, and the proline content of seedlings confronting increasing water stress was increased sharply .When the concentration of NaCl increased to some extent , the salt toxicity occurred besides water stress . The results are valuableto elucidate the ecogeographical patterns and mechanisms for adaptation of such early-spring ephemeral plants in the desert environments  相似文献   

12.
A new semi-mycotrophic species, Burmannia larseniana , is described from northern Thailand. The species is related to B. pusilla , a species widely distributed in Cambodia, Vietnam, Burma, India and Sri Lanka, but can be easily distinguished from the latter by its succulent stem, single-veined leaf, and the outer perianth lobes with double margins that encircle the inner perianth lobes. The ecological preferences of the species are also discussed.  相似文献   

13.
Soldanella rugosa Zhang & Kadereit is a synonym to the real S. marmarossiensis Klášt. Correct name for the taxon called S. marmarossiensis by Zhang and Kadereit as defined by them is S. haretii G. Grint. but it comprises at least three different taxa.  相似文献   

14.
Pan IC  Liao DC  Wu FH  Daniell H  Singh ND  Chang C  Shih MC  Chan MT  Lin CS 《PloS one》2012,7(4):e34738
Oncidium is an important ornamental plant but the study of its functional genomics is difficult. Erycina pusilla is a fast-growing Oncidiinae species. Several characteristics including low chromosome number, small genome size, short growth period, and its ability to complete its life cycle in vitro make E. pusilla a good model candidate and parent for hybridization for orchids. Although genetic information remains limited, systematic molecular analysis of its chloroplast genome might provide useful genetic information. By combining bacterial artificial chromosome (BAC) clones and next-generation sequencing (NGS), the chloroplast (cp) genome of E. pusilla was sequenced accurately, efficiently and economically. The cp genome of E. pusilla shares 89 and 84% similarity with Oncidium Gower Ramsey and Phalanopsis aphrodite, respectively. Comparing these 3 cp genomes, 5 regions have been identified as showing diversity. Using PCR analysis of 19 species belonging to the Epidendroideae subfamily, a conserved deletion was found in the rps15-trnN region of the Cymbidieae tribe. Because commercial Oncidium varieties in Taiwan are limited, identification of potential parents using molecular breeding method has become very important. To demonstrate the relationship between taxonomic position and hybrid compatibility of E. pusilla, 4 DNA regions of 36 tropically adapted Oncidiinae varieties have been analyzed. The results indicated that trnF-ndhJ and trnH-psbA were suitable for phylogenetic analysis. E. pusilla proved to be phylogenetically closer to Rodriguezia and Tolumnia than Oncidium, despite its similar floral appearance to Oncidium. These results indicate the hybrid compatibility of E. pusilla, its cp genome providing important information for Oncidium breeding.  相似文献   

15.
Meicai Wei 《Insect Science》1994,1(2):110-123
Abstract  The following new taxa from China are proposed in the Fenusini : Profenusa chrysichlorita sp. nov., Nefusa sinica sp. nov., Nefusa brevis sp. nov., Metallus sichuanensis sp. nov. , Metallus wangi sp. nov. , Metallus mai sp. nov., Nefusa sinica sp. nov. Nefusa bratis sp. nov., Metatlus sichuanensis sp. nov., Birmella discoidalisa sp. nov., Okutanius pekingensis sp. nov. All these genera except for Birmella with Fenusa pusilla (Lepel.), Fenella monilicornis Thomson and Profenusa hirashima Togashi are new records from China. New taxa are described and figured. Keys to genera and species of the tribe Fenusini from China are proposed.  相似文献   

16.
LOVELESS, A. R., 1985. The occurrence of ergot fungi (Clavicipitales) on the genus Hyparrhenia in southern Africa . In southern Africa the presence of ergots has been confirmed on 11 wild grasses of the genus Hyparrhenia . Two species of Claviceps are involved. One of them has predominantly triangular conidia, and is therefore identified as C. pusilla . The other has very characteristic truncate conidia, and is either an undescribed species or C. inconspicua , depending upon how problems in the identification of species of Claviceps are to be resolved. On Hyparrhenia, C. pusilla is restricted to species belonging to the series Cymbariae, and the undetermined species of Claviceps infects various species of Hyparrhenia belonging to at least four other series of the genus.  相似文献   

17.
Pseudobalta , a new blattellid genus, is described. It differs from oviparous Balta Tepper in being ovoviviparous and the male having a tergal gland on the first abdominal segment. Pseudobalta comprises two species previously placed in Balta (P. pusilla (Hebard) comb.n. and P. cinctella (Hebard) comb.n.) and P. queenslandica sp.n. This is the fourth known blattellid, and the second taxon in the Pseudophyllodromiinae, that reproduces by ovoviviparity.  相似文献   

18.
Gagea tisoniana Peruzzi et al. sp. nov. is described and its taxonomic relationship is discussed. The new species, which appears to be endemic to central Italy, is close to G. pratensis (Pers.) Dumort., G. pusilla (F. W. Schmidt) Sweet, and other mainly poorly known [i.e. G. succedanea Griseb. et Schenk, G. transversalis Stev., and G. paczoskii (Zapal.) Grossh.] or as yet undescribed taxa from eastern Europe and the eastern Mediterranean area. The recognition of the new taxon G. tisoniana is claimed on the basis of anatomical, karyological, ecological, and phytogeographical data. Maps of the Italian distribution of G. pratensis (2 n  = 60), G. pusilla (2 n  = 24), and G. tisoniana (2 n  = 24) are presented, together with an analytical identification key. Finally, G. pratensis is recorded here for the first time in Tuscany (Monte Cetona).  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 337–347.  相似文献   

19.
We used light and scanning electron microscope analyses to quantify morphometric features (valve length, width, stria density, lineola density and valve curvature) from the observation of valves representing Seminavis pusilla. Cluster analysis based on Gaussian mixture models and the expectation‐maximization algorithm was used for delineating two species, Seminavis pusilla sensu stricto and Seminavis lata (Krammer) Rioual comb. et stat. nov. By comparison with S. pusilla, S. lata is characterized by wider valves and lower stria density. The two species have also markedly different ecology. S. pusilla is most abundant in the most saline lakes of the dataset, while S. lata is most abundant in the less saline lakes. Our results indicate that combining the two species into S. pusilla sensu lato would lead to a loss of ecological information and a decrease of the performance of transfer functions developed for quantitative reconstruction of past salinity from fossil diatom assemblages in sediment cores.  相似文献   

20.
记述采自中国浙江及河北省飞虱科2新纪录种:三齿长突飞虱Stenocranus pacificus Kirkaldy,1907和普思黎氏飞虱Ribautodelphax pusilla Emeljanov,1972,提供了成虫外形照片及雄性外生殖器特征图。研究标本均保存在西北农林科技大学昆虫博物馆。  相似文献   

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