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1.
Peter Lesica 《Brittonia》2005,57(1):47-54
Erigeron parryi was described in 1890 from a single collection from southwest Montana. No additional collections were made during the following 90 years. Recent floristic treatments have synonomized E. parryi under E. ochroleucus. I used principal components and discriminant analyses of morphological characters to examine the relationship of E. parryi to its presumed closest relatives, E. ochroleucus, E. radicatus, and E. scribneri, in light of several populations discovered in the past 20 years. Erigeron parryi should be considered a distinct species. It can be readily distinguished from closely related species based on indument and caudex morphology. It is allopatric with E. ochroleucus and E. scribneri and ecologically separated from E. radicatus. Erigeron scribneri is intermediate between E. ochroleucus and E. radicatus and is probably best treated as a variety of one or the other of these species.  相似文献   

2.
The Ganitrus group of Elaeocarpus L. (incl. Elaeocarpus Sect. Ptilanthus Schltr.) as found in Malesia is examined and some understanding reached. The group is more complex and speciose in eastern Malesia, especially in Papuasia (with the Philippines, Sulawesi and Maluku somewhat less rich) than in western and central Malesia. E. angustifolius Blume (syn. E. ganitrus & E. sphaericus auctt. mult.) — the source of the ornamental beads known as rudraksha of eastern commerce, from which malas or rosaries are made — is considered to be very variable in Malesia and probably varies further in the extremes of its range; outside Malesia the Ganitrus group is represented by ‘E. angustifolius s.l.’ only. The following species are recognised: E. altisectus Schltr. with a new subsp. carrii Coode from New Guinea; E. angustifolius Blume; E. avium Coode sp. nov. from New Guinea; E. buderi Coode; E. dolichostylus Schltr. with E. chloranthus treated as var. chloranthus (A. C. Sm.) Coode from New Guinea, with a new var. elliptifolius Coode from the Talaud/Sangihe Is. and a new var. hentyi Coode (replacing and re-interpreting subsp. collinus Coode) from New Guinea; E. fulvus Elmer; E. kaniensis Schltr.; E. ornatus Coode sp. nov. from New Guinea; E. osiae Coode sp. nov. from Bougainville I.; E. ptilanthus Schltr.; E. ramiflorus Merr. and E. trichopetalus Merr. & Quisumb. — a total of 12 species although the last two are perhaps not truly distinct from E. angustifolius. The stone sculpturing is discussed and some useful characters revealed. Attention is drawn to a collection from mid-altitude in Papua New Guinea, inadequately known but probably a new species in this group.  相似文献   

3.
《Journal of bryology》2013,35(2):122-132
Abstract

Taxonomy of some European species of Ephemerum is reviewed. As in several other recent studies, E. minutissimum Lindb. is regarded as a distinct species from E. serratum (Hedw.) Hampe; it is recorded from N. America (by the newly designated lectotype and other specimens) and Turkey, in addition to Europe. E. serratum var. angustifolium Bruch & Schimp. may be a synonym of E. minutissimum; the costate forms E. serratum var. praecox A.W.H.Walther & Molendo and E. intermedium Mitt. in Braithw. are treated as synonyms of E. serratum s.str. Type specimens of E. stellatum H.Philib. are described, a lectotype is designated and it is placed as a synonym of E. serratum s.str. E. hibernicum Holyoak & V.S.Bryan is regarded as a synonym of E. rutheanum Schimp. in Ruthe. The latter is shown to be a rare, European endemic taxon with modern records from Ireland, S. Wales, Germany and The Netherlands, and old records from France and W. Poland; a lectotype is designated. Forms intermediate between E. sessile (Bruch.) Müll.Hal. and the N. American E. crassinervium (Schwägr.) Hampe occur in several countries in W. Europe, some of them indistinguishable from some of the American plants; forms intermediate between E. sessile and E. rutheanum are recorded from S. Portugal and (rarely) Ireland. Differences between E. crassinervium, E. sessile and E. rutheanum in characters of leaves, tubers and capsules are shown to be slight, with considerable overlap. Hence all three taxa are treated as subspecies of E. crassinervium. A revised key to European Ephemerum and Micromitrium is presented.  相似文献   

4.
Abstract Eucalyptus paliformis is restricted to seven small populations within an area of <5 km2 on the Wadbilliga Plateau of south-eastern NSW. It occurs as a dominant tree in habitats superficially similar to those of the more widespread E. fraxinoides, which dominates forests immediately adjacent to the E. paliformis populations. This study examined factors which may influence the replacement of E. fraxinoides by E. paliformis, and similarly, factors which exclude E. paliformis from sites dominated by E. fraxinoides. Seedling growth and competition experiments indicated that E. fraxinoides outcompetes E. paliformis under unburnt field conditions, on field soils, under high and low moisture regimes, under high light and high nutrient conditions, and under a range of temperature regimes. Thus, it is likely that E. paliformis is excluded from E. fraxinoides sites by competition. However, further investigation of the competitive relationship between the two species under recently-burnt conditions is still required to test this hypothesis. The exclusion of E. fraxinoides from E. paliformis sites is unlikely to be due to soil types or moisture regimes. Further, temperature regimes do not appear to be important in reducing the competitive advantage of E. fraxinoides over E. paliformis, leaving survival at low temperature extremes as the most promising avenue for further investigation. Temperature measurements, and evidence for low temperature dormancy mechanisms in seeds of E. paliformis but not E. fraxinoides, support the hypothesis that E. fraxinoides is excluded from E. paliformis sites by low temperature extremes.  相似文献   

5.
ABSTRACT. Since May 1979, 190 rodents in the family Sciuridae, representing three genera and nine species, have been collected in the western United States and northern Mexico and examined for coccidia; 71 (37%) had coccidian oocysts in their feces. These included 2 of 12 (17%) Eutamias canipes; 7 of 12 (58%) E. dorsalis; 18 of 50 (36%) E. merriami; 33 of 96 (34%) E. obscurus; 3 of 4 (75%) E. townsendii; 3 of 9 (33%) Sciurus aberti; 1 of 1 S. griseus; 1 of 1 Tamiasciurus hudsonicus mogollonensis; and 3 of 5 (60%) T. mearnsi. The following coccidians were identified from infected rodents: Eimeria cochisensis n. sp. and Eimeria dorsalis n. sp. from E. canipes; E. cochisensis, E. dorsalis, and E. tamiasciuri from E. dorsalis; E. dorsalis and E. tamiasciuri from E. merriami; E. cochisensis, E. dorsalis, E. tamiasciuri, and E. wisconsinensis from E. obscurus; E. cochisensis and E. dorsalis from E. townsendii; E. ontarioensis and E. tamiasciuri from S. aberti; E. tamiasciuri from S. griseus; E. tamiasciuri and E. toddi from T. h. mogollonensis; and E. tamiasciuri from T. mearnsi. Sporulated oocysts of Eimeria dorsalis n. sp. were ovoid, 21.9 × 16.8 (17–24 × 14–20) μm with sporocysts ovoid, 11.5 × 6.9 (10–14 × 6–8) μm. Sporulated oocysts of Eimeria cochisensis n. sp. were spheroid to subspheroid, 16.7 × 15.3 (15–18 × 14–17) μm, with sporocysts ovoid, 8.4 × 5.6 (6–11 × 4–7) μm. Fifty-five of 71 (77%) infected hosts had oocysts of only one eimerian species in their feces at the time they were examined. One eimerian, E. tamiasciuri, was found in seven of nine host species in three genera. A list is provided of all eimerians (22, including the species described here) that have been described in the literature from Eutamias, Sciurus, and Tamiasciurus spp.  相似文献   

6.
7.
Ecballocystopsis (Oocystaceae, Chlorellales, Trebouxiophyceae) is a rare green algal genus, represented by only five taxa: E. dichotoma var. dichotoma from China and E. indica, E. desikacharyi, E. himalayensis and E. dichotoma var. minuta from India. Here we propose the novel variety E. dichotoma var. anandii from Jharkhand, synonymization of E. himalayensis with E. dichotoma and erection of E. dichotoma var. minuta to a separate species as E. minuta stat. et comb. nov. These taxonomic changes are well supported by the results of a multivariate analysis based on a numerical taxonomic approach. Cluster analysis (CA), principal component analysis (PCA) and principal coordinates analysis (PCoA) were performed to resolve the species delimitation ambiguity and supplement the morphology-based classification of the genus. Ecballocystopsis himalayensis and E. dichotoma grouped in a single cluster along with the proposed new variety, while E. indica, E. desikacharyi and E. minuta formed separate clusters. An identification key to the species of the genus Ecballocystopsis is also presented.  相似文献   

8.
An example from the genus Eucalyptus is used to argue that hybridization may be of evolutionary significance as a means of gene dispersal where seed dispersal is limited. A previous study of regeneration of E. risdonii and E. amygdalina indicated that the current selective regime was favoring E. risaonii. However, the dispersal of E. risdonii by seeds is shown to be limited (s, = 4.6 m). By comparison, the flow of E. risdonii genes into the range of E. amygdalina by pollen dispersal and F1 hybridization is widespread (sp = 82 m). While the actual level of hybridization is low, interspecific hybridization effectively doubles the dispersal of E. risdonii genes into the range of E. amygdalina. This pollen flow can have a significant genetic impact, since isolated hybrids or patches of abnormal phenotypes have been found 200–300 m from the species boundary. Based on lignotuber size, some of these patches appear to have been founded by F1 hybrids. The frequency of E. risdonii types in the patches appears to increase with patch size suggesting that there is selection for this phenotype in subsequent generations. E. risdonii-like individuals were recovered in the progeny from both intermediate and E. risdonii backcross phenotypes. These results suggest that E. risdonii may invade suitable habitat islands within the E. amygdalina forest, independently of seed migration, by long-distance pollen migration followed by selection for the gene combinations of the pollen parent.  相似文献   

9.
Takamatsu  Susumu  Sato  Yukio  Mimuro  Genki  Kom-un  Sawwanee 《Mycoscience》2003,44(3):165-171
 A new species of Erysiphe sect. Uncinula is described and illustrated from Japan. Erysiphe wadae sp. nov., found on Japanese beech (Fagus crenata, Fagaceae), is characterized by having two types of appendages, i.e., a long (true) appendage arising from the equatorial zone of the ascomata, and a short appendage arising from the upper part of the ascomata. This characteristic is shared by E. simulans, E. australiana, E. flexuosa, E. liquidambaris, E. prunastri, and E. togashiana. Erysiphe wadae differs from the latter five species in its brown-colored appendage. Erysiphe simulans is most similar to E. wadae, but differs in its loosely uncinate appendage and smaller number of ascospores. Identity of the nucleotide sequences of the rDNA ITS region is 92.3% between the two species. The significance of the two types of appendage in taxonomy and phylogeny of powdery mildews is discussed based on molecular phylogenetic analysis. Received: November 8, 2002 / Accepted: January 29, 2003 Acknowledgments We are grateful to Drs. Yukio Harada and Hideki Naito for help in collecting powdery mildew specimens; Dr. Uwe Braun for providing the specimen of E. flexuosa; and Mr. Tetsuya Hirata and Miss Sanae Matsuda for nucleotide sequences of E. togashiana and E. flexuosa. This work was partially supported by a Grant-in-Aid for Scientific Research (No. 13660047) from Ministry of Education, Culture, Sports, Science and Technology, Japan.  相似文献   

10.
Five new species are described:Eremostachys codonocalyx from NE. Iran (related toE. subspicata),E. stenocalycina from NE. Afghanistan (related toE. alberti andE. hissarica),E. salangensis from NE. Afghanistan (close toE. bamianica),E. freitagii from E. Afghanistan (similar but not closely related toE. vulnerans), andE. andersii from E. Afghanistan (similar but not closely related toE. vulnerans), andE. andersii from NE. Afghanistan of isolated systematic position.
Florae Iranicae praecursores 5–9.  相似文献   

11.
12.
Jozef Somogyi 《Biologia》2006,61(4):381-385
Taxonomic, nomenclatural and chorological notes on several taxa of the genus Echinodorus are given. A new species E. maculatus is described. The name Alisma intermedium (basionym of the name E. intermedius) is lectotypified. Echinodorus major and E. martii should be treated as two distinct taxa. The name E. xinguensis was invalidly published. It is also confirmed that E. africanus, E. veronikae and E. viridis (all belonging to the E. uruguayensis group) do not originate from Africa. The name E. bleherae should be written with a female suffix (-ae); this name is considered here as a synonym of the earlier name E. grisebachii.  相似文献   

13.
The type II or Sec-dependent secretion system is used by diverse Gram-negative bacteria for secretion of extracellular proteins. Of the 12–15 proteins involved in secretion, the requirement for many has not been demonstrated and little is known about their functions in the secretion process. The plant pathogens Erwinia chrysanthemi and Erwinia carotovora secrete extracellular pectate lyases (Pels) using the type II or Out pathway. However, these two bacteria cannot secrete Pels encoded by heterologously expressed genes from the other species, suggesting the presence of species-specific recognition factors in the Out systems of the two Erwinia species. We previously reported the isolation of a cosmid clone, pCPP2006, from E. chrysanthemi EC16, which enables Escherichia coli to secrete heterologously expressed E. chrysanthemi Pels. Sequencing in a region required for secretion revealed the presence of 12 genes, outC-M and outO. We report here the construction of functionally non-polar mutations in each gene in the outC-M operon and outS and outB using a polAts strain of E. coli to facilitate homologous recombination between out genes carrying deletions and their wild-type copies on pCPP2006. By testing for complementation of each deletion with wild-type out genes from E. chrysanthemi EC16 and E. carotovora SCRI193 we have demonstrated that: (i) each out gene is required for secretion of E. chrysanthemi PelE from E. coli with the exception of outH; (ii) each mutation can be complemented by its homologue from E. carotovora, except for outC and outD; (iii) outC and outD from E. carotovora do not confer secretion of Pel1 on the E. chrysanthemi Out system; and (iv) Pel1 secretion can be conferred on the E. chrysanthemi Out system by the presence of outC-M, S and B from E. carotovora. The data suggest that OutC and OutD are gatekeepers of the Out system involved in recognition of Pels targeted for secretion but that OutC and OutD from E. carotovora cannot be successfully assembled into the E. chrysanthemi Out system.  相似文献   

14.
SYNOPSIS. Eimeria worleyi n. sp. and Eimeria barretti n. sp. from the pika Ochotona princeps from Alberta and Eimeria pallasi n. sp. and Eimeria shubini n. sp. from the pika Ochotona pallasi from Central Kazakhstan are described. Oocysts of E. worleyi were 12–16 by 10–15 μ (mean 13.5 by 12.5 μ) and spherical to subspherical. E. barretti oocysts were ellipsoidal to slightly ovoid and 27–36 by 21–27 μ (mean 32.9 by 23.8 μ). Oocysts of E. pallasi were ellipsoidal or ovoid and 19–34 by 17–26 μ (mean 26.3 by 21.3 μ). E. shubini oocysts were spherical and 22 μ in diameter. E. kriygsmanni Yakimoff and Gousseff, 1938 of Svanbaev (1958) in O. pallasi, [non] E. kriigsmanni Yakimoff and Gousseff, 1938 in Mus musculus, is a synonym of E. pallasi. E. musculi Yakimoff and Gousseff, 1938 of Svanbaev (1958) in O. pallasi, [non] E. musculi Yakimoff and Gousseff, 1938 in Mus musculus, is a synonym of E. shubini.  相似文献   

15.
SYNOPSIS. Eimerians from 27 gray squirrels Sciurus carolinensis sampled in Waterloo County were studied. Two double-walled species, E. ontarioensis n. sp. which was piriform (36.8 × 23.5) and E. confusa Joseph which was subspherical (35.7 × 28.4), were described and compared with similar species from the genus Sciurus. Eimeria sp., ellipsoidal (24.9 × 14.4), from Ontario gray squirrels resembled E. ascotensis and E. neosciuri and was a new eimerian record from Ontario. The zoogeographic significance of E. ontarioensis n. sp. and E. sp. in North American gray squirrels is discussed.  相似文献   

16.
Sun G  Tang H  Salomon B 《Genetica》2006,127(1-3):55-64
The morphological similarity of Elymus trachycaulus to the Eurasian E. caninus has often been noted. This has lead to controversial and contradicting taxonomic treatments. Nevertheless, there has been no systematic investigation on molecular genetic similarity between E. trachycaulus and E. caninus. In this study, random amplified polymorphic DNA (RAPD) analysis was used to study the similarity between the two species. RAPD analysis of 38 samples representing E. caninus and E. trachycaulus complex yielded 111 interpretable RAPD bands. The Jaccard’s similarity values for E. caninus ranged from 0.38 between accessions H10345 and H10353 to 0.97 between accessions H8745 and H10096, with an average of 0.67. The Jaccard’s similarity values for E. trachycaulus complex ranged from 0.09 between E. trachycaulus ssp. subsecundus (PI 537321) and E. trachycaulus ssp. violaceus (PI 272612) to 0.78 between accessions PI 315368 and PI 372644, with an average of 0.43. The results from different analyses (NJ and PCA) were similar but not identical. The molecular genetic separation between E. caninus and E. trachycaulus was consistent. The PCA analysis clearly separated all E. caninus accessions from E. trachycaulus and its subspecies. The NJ analysis also showed separation between most accessions of E. caninus and E. trachycaulus. Further analysis excluding E. trachycaulus ssp. subsecundus and ssp. violaceus revealed that E. caninus species and E. trachycaulus species were clearly separated into two distinct groups. The RAPD data thus support the treatment of E. caninus and E. trachycaulus as distinct species. The analyses further indicate that E. violaceus is nested within E. trachycaulus, and more related to E. trachycaulus complex rather than to E. caninus.  相似文献   

17.
The tropical Indo-Pacific genus Excoecaria L. (Euphorbiaceae) has several closely related species in Australia whose taxonomic relationships are unclear. The most widely reported species in Australia is the mangrove species Excoecaria agallocha L. (type species), whose taxonomic and geographic limits are difficult to define from its closely related species or sub-species. Two additional taxa have also been described but not clearly differentiated from the type species: Excoecaria dallachyana Baillon and Excoecaria ovalis Endl. This project aimed to determine the taxonomic relationships of the Australian Excoecaria species using both leaf morphological data and DNA sequence data from the internal transcribed spacer (ITS) region of ribosomal genes. The nucleotide differences in the examined ITS1 region show that E. agallocha from eastern Australia and E. ovalis from Western Australia respectively, are genetically uniform within species but differ from each other consistently, thus supporting species status. The leaf morphological data also support this view: single factor analysis of variance consistently separated E. ovalis from E. agallocha on the basis of leaf width, leaf length and length of petiole. In contrast, E. ovalis from the Gulf of Carpentaria differs only slightly from E. ovalis in Western Australia, but no evidence was found to suggest any leaf morphological differentiation within this species. The analysis also suggests that E. dallachyana is not closely related to either mangrove species E. agallocha or E. ovalis, despite superficial morphological similarities.  相似文献   

18.
对亚草叶蝉属进行系统研究并首次报道其在中国分布,共记述5种:E. acarifer (Lethierry),E. hilaris (Melichar),E. magnus Mitjaev,E. medius (Mulsant & Rey) 和E. pratensis Emeljanov,其中E. hilaris (Melichar) 和E. medius (Mulsant & Rey) 为中国新记录种。文中提供了分种检索表和雄性外生殖器特征图,并首次记述和提供雌性生殖器特征。  相似文献   

19.
Hand-emasculated Elymus canadensis pollinated by E. triticoides, E. dasystachys, and Agropyron smithii yielded 15, 21, and 1 viable hybrid seeds from 56, 52, and 52 florets, respectively. The 28-chromosome species—E. canadensis, E. triticoides, and E. dasystachys—behaved meiotically as allotetraploids and consistently formed 14 bivalents at metaphase I. Octoploid A. smithii, 2n = 56, averaged 0.41I, 27.72II, and 0.03IV in 87 metaphase-I cells. Agropyron smithii is apparently an allooctoploid or a segmental autoallooctoploid. Meiosis was similar in the E. canadensis X E. triticoides and E. dasystachys hybrids. Chromosome pairing was very low in both hybrids, about two loosely connected open-ended bivalents per cell, and may not represent genuine homologies. The genomes of E. canadensis are distinctly different from those of E. triticoides and E. dasystachys. The E. canadensis X A. smithii hybrid averaged 13.37I and 14.31II in 76 metaphase-I cells. More than half of the bivalents were closed at both ends. Inability to distinguish between auto- and allosyndesis resulted in two interpretations of genome relations. Either A. smithii is an alloploid with two of its four genomes similar to those of E. canadensis, or it is a segmental autoalloploid genomically unrelated to E. canadensis. The first interpretation is favored. Agropyron dasystachyum, or one of its close relatives, and E. triticoides are suggested as possible parents of A. smithii.  相似文献   

20.
We have proposed the revival of the name Entamoeba nuttalli for a virulent ameba strain, P19‐061405, from a rhesus macaque and located it phylogenetically between E. histolytica and E. dispar. As E. nuttalli was originally described for an ameba found in a toque macaque in Sri Lanka, the prevalence and characteristics of Entamoeba species in wild toque macaques were examined. PCR analysis of 227 stool samples from six locations showed positive rates for E. nuttalli, E. dispar, and E. histolytica of 18.5%, 0.4%, and 0%, respectively. Fifteen E. nuttalli strains were cultured successfully from five locations. The 18S ribosomal RNA gene showed only three nucleotide differences in comparison with P19‐061405 strain. In isoenzyme analysis, the pattern of hexokinase in Sri Lankan strains was different from that of P19‐061405 strains and the difference was confirmed by analysis of the genes. Hepatic inoculation of one of the Sri Lankan E. nuttalli strains in hamsters resulted in amebic abscess formation and body weight loss. These results demonstrate that E. nuttalli is prevalent in wild toque macaques and that several characteristics of the strains are unique. We conclude that use of the name E. nuttalli is appropriate for the new Entamoeba species found in nonhuman primates.  相似文献   

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