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1.
Seventy-three taxa of silica-scaled chrysophytes were found with LM and TEM in 264 samples from 141 Finnish water bodies, including the genera Mallomonas (40 taxa), Synura (9), Chrysosphaerella (3), Spiniferomonas (8) and Paraphysomonas (13). More than half of the taxa are recorded for the first time from Finland and five (Mallomonas actinoloma v. actinoloma, M. favosa, M. mangofera f. gracilis, M. scrobiculata and Spiniferomonas serrata) are new to Europe. Most taxa are illustrated with TEM micrographs and the taxonomy of some interesting species is discussed in detail. The seasonal occurrence of the commonest species is described.  相似文献   

2.
The taxonomic status and biogeography of the North American Raphia species is reviewed using adult morphology, larval host plants, geographic phenotypic variation, and variation of mtDNA COI barcode sequences. Lack of diagnostic morphological differences, combined with relatively low mtDNA barcode divergences and clinal phenotypic variation in key geographic regions indicate that the six previously recognized species of North American Raphia are best interpreted as parapatric subspecies. Raphia frater abrupta Grote, stat. n., R. f. coloradensis Putnam-Cramer, stat. r., R. f. piazzi Hill, stat. n., and R. f. elbea Smith, stat. n., are accordingly revised to subspecies of R. frater Grote. Type locality restrictions are provided for Raphia abrupta and Raphia frater and a neotype is designated for Raphia frater var. coloradensis.  相似文献   

3.
4.
The compatible solute N-acetyl-β-lysine is unique to methanogenic archaea and is produced under salt stress only. However, the molecular basis for the salt-dependent regulation of N-acetyl-β-lysine formation is unknown. Genes potentially encoding lysine-2,3-aminomutase (ablA) and β-lysine acetyltransferase (ablB), which are assumed to catalyze N-acetyl-β-lysine formation from α-lysine, were identified on the chromosomes of the methanogenic archaea Methanosarcina mazei Gö1, Methanosarcina acetivorans, Methanosarcina barkeri, Methanococcus jannaschii, and Methanococcus maripaludis. The order of the two genes was identical in the five organisms, and the deduced proteins were very similar, indicating a high degree of conservation of structure and function. Northern blot analysis revealed that the two genes are organized in an operon (termed the abl operon) in M. mazei Gö1. Expression of the abl operon was strictly salt dependent. The abl operon was deleted in the genetically tractable M. maripaludis. Δabl mutants of M. maripaludis no longer produced N-acetyl-β-lysine and were incapable of growth at high salt concentrations, indicating that the abl operon is essential for N-acetyl-β-lysine synthesis. These experiments revealed the first genes involved in the biosynthesis of compatible solutes in methanogens.

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5.
Four species of Triplocania, three with M3 simple, based on male specimens and one with forewing M3 forked, based on male and female specimens, are here described and illustrated, namely: Triplocania bravoi sp. n. (Napo: Ecuador), Triplocania erwini sp. n. (Napo: Ecuador), Triplocania trifida sp. n. (Mato Grosso and Rondônia: Brazil) and Triplocania lamasoides sp. n. (Rondônia: Brazil). They differ from all the other species in the genus, in which the males are known, by the hypandrium and phallosome structures. The female is first described for the M3 forked group. The identification key for males of the M3 forked group is updated.  相似文献   

6.
Gary A P G 《ZooKeys》2010,(55):1-75
Two of three species previously classified in Calosota Curtis (Hymenoptera: Eupelmidae) from the Neotropical region are transferred to Eupelminae. Calosota eneubulus (Walker) from Galapagos Islands is transferred to Eupelmus Dalman as Eupelmus (Eupelmus) eneubulus (Walker), comb. n., and Calosota silvai (Brèthes) from Chile is transferred to Brasema Cameron as Brasema silvai comb. n. Calosota cecidobius (Kieffer) from Argentina is retained in Calosota, with reservation, as an unrecognized species. The species of Calosota from the New World excluding South America are revised. Eleven species are recognized, including the seven newly described species Calosota albipalpus sp. n. (Costa Rica, Mexico, USA, Venezuela), Calosota bicolorata sp. n. (USA), Calosota elongata sp. n. (USA), Calosota longivena sp. n. (USA), Calosota panamaensis sp. n. (Panama), Calosota setosa sp. n. (Bahamas, Dominican Republic, USA), and Calosota speculifrons sp. n. (Costa Rica, USA). The 11 regional species and the Palaearctic species Calosota vernalis Curtis are keyed and illustrated. Calosota vernalis is not known to occur in the New World but is included in the key and diagnosed because it has been intercepted in quarantine in Canada. Calosota pseudotsugae Burks is placed in synonymy under Calosota acron (Walker), syn. n.,and Calosota kentra Burks, Calosota montana Burks and Calosota septentrionalis Hedqvist are placed in synonymy under Calosota aestivalis Curtis syn. n. Calosota modesta Bolívar y Pieltain is removed from synonymy under Calosota viridis Masi, stat. rev., and Calosota viridis, Calosota matritensis Bolívar y Pieltain, and Calosota coerulea Nikol’skaya are placed in synonymy under Calosota metallica (Gahan), syn. n. Calosota grylli Erdös is confirmed as a separate species from Calosota metallica based on features of both sexes. It is suggested that Calosota ariasi Bolívar y Pieltain may be a synonym of Calosota aestivalis, Calosota bolivari Askew may be a synonym of Calosota agrili Nikol’skaya, Calosota dusmeti Bolívar y Pieltain may be a synonym of Calosota violascens Masi, and Calosota lixobia Erdös likely is not a junior synonym of Calosota obscura Ruschka, but formal nomenclatural changes are not proposed prior to a comprehensive Palaearctic revision. Previous interpretation of the mesoscutum in Calosota and Balcha Walker is also modified to include the presence of anteroadmedian lines in addition to notauli and parapsidal lines.  相似文献   

7.
A new genotyping tool has been developed and evaluated for Metarhizium anisopliae var. anisopliae. The tool is based on Restriction Fragment Length Polymorphism (RFLP) analysis of three chitinase genes that are functionally linked to insect-pathogenicity of this fungus. It allowed for discrimination of 14 genotypes among 22 M. anisopliae var. anisopliae strains of a world wide collection. Analyses revealed that the approach may also be applicable to other Metarhizium varieties. The new tool will be useful for genetic characterization of M. anisopliae var. anisopliae strains, and it is applicable for laboratories with limited access to molecular diagnostic equipment.  相似文献   

8.
9.
《Life sciences》1995,57(11):PL131-PL135
The effect of 7-nhro indazole (7-NI) and a range of substituted indazole derivatives on nitric oxide synthase (NOS) enzyme activity in homogenates of rat cerebellum, bovine endothelial cells and lung from endotoxm-pretreated rats was investigated. 3-bromo 7-nitro indazole was either equipotent (IC50, 0.86 ± 0.05 μM c.f. 0.78 ± 0.2 μM, n = 6, P > 0.05) or approximately 4x (IC50, 0.17 ± 0.01 μM c.f. 0.71 ± 0.01 μM, n = 6, P < 0.05) or 20x (IC50, 0.29 ± 0.01 μM c.f. 5.8 ± 0.4 μM, n = 6, P < 0.05) more potent than 7-NI as an inhibitor of bovine endothelial, rat cerebellar and rat lung NOS enzyme activity respectively. 2,7-dinitro indazole also inhibited NOS in all three tissue sources with a potency similar to that of 7-NI. These results suggest that 3-bromo 7-NI and 2,7-dinitro indazole may prove to be useful additional tools with which to examine the biological properties of nitric oxide (NO).  相似文献   

10.
Abstract:Leptogium imbricatum P.M. Jørg. sp. nov. and L. intermedium (Arnold) Arnold are established as the correct names for two fairly widespread, small species: L. imbricatum has an arctic-alpine distribution. Leptogium intermedium was previously mostly named L. minutissimum (Flörke) Fr., the type of which is L. subtile (Schrader) Torss., a distinct species usually growing on rotting wood or debris. Leptogium magnussonii Degel. & P.M. Jørg, mainly from maritime rock outcrops in Norway and Sweden, is described as new. The species complexes of L. plicatile (Ach.) Leighton and L. schraderi (Bernh.) Nyl. are discussed. The differences between L. byssinum (Hoffm.) Nyl. and L. biatorinum (Nyl.) Leighton are given, and L. aquale (Arnold) P.M. Jørg. comb. nov., a taxon related to the latter, is considered to be a distinct species growing in mountain brooks in Central Europe. Leptogium rivale Tuck. is recorded as new to Europe, from Romania. Leptogium bellopratense Hy is shown to be a synonym of L. brebissonii Mont. New records for L. coralloideum (Meyen & Flotow) Vainio, L. massiliense Nyl and L. rivulare (Ach.) Mont. are given. A preliminary key to the small European species (north of the Alps) is appended. The following names have been lecto- or neotypified: Collema byssinum Hoffm., Collema pulvinatum Hoffm., Leptogium bellopratense Hy., Leptogium crenulatum Watson, Leptogium massiliense Nyl., Leptogium minutissimum var. intermedium Arnold, Leptogium minutissimum f. plumbeum Zwackh ex Arnold, Leptogium pusillum var. aquale Arnold, Leptogium rivulare var. crenatulum Nyl., Leptogium scotinum var. crenatum Nyl., Lichen byssinus Hoffm., Lichen minutissimus Flörke, Lichen schraderi Bemh., Lichen subtilis Schrader and Parmelia scotina var. lophaea Ach.  相似文献   

11.
Noel H. Holmgren 《Brittonia》1987,39(4):423-427
The curl-leaf mountain-mahogany of the Intermountain Region is given a varietal name for the first time,Cercocarpus ledifolius var.intermontanus. It is distinguished from var.ledifolius by its broader, less pubescent leaves, its often longer petioles, and its often longer hypanthium tube. The nameC. ledifolius var.intercedens C. Schneider is based on a likely hybrid betweenC. ledifolius var.intermontanus andC. intricatus. The namesC. hypoleucus andC. ledifolius var.intercedens f.hirsutus fall into synonymy underC. ledifolius var.ledifolius. A lectotype is selected for the quadrinomialC. ledifolius var.intercedens f.hirsutus.  相似文献   

12.
B. A. Wafai  A. K. Koul 《Genetica》1983,60(2):157-160
Tulipa clusiana is characterized by a highly variable phenotype. The species comprises var. chrysantha Sealy (2n=2x=24), var. stellata Regel (2n=3x=36; 2n=4x=48) and var. typica Regel (2n=2x=24; 2n=4x=48; 2n=5x=60). Several populations of these varieties were all found to exhibit remarkable uniformity in basic karyotype. A few plants had some structurally altered chromosomes otherwise unknown within the species and its allies. These chromosomes are suspected to be products of translocations. They are very long with almost median centromere. Occasional aneusomaty and polysomaty have also been observed in some plants. The evolutionary significance of these aberrations is discussed.  相似文献   

13.
Veronica panormitana Tin. inGuss. (sparsely distributed from Corsica and Sicily to Syria) andV. trichadena Jord. etFourr. var.freyniana M. Fisch. (Mallorca) are diploid (2n = 18), and very probably the ancestors of the allopolyploidV. cymbalaria Bod. The latter consists of tetraploid (2n = 36) and hexaploid (2n = 54) strains (confirmed on new material from Italy, Greece, and Turkey). The diploid taxa are morphologically well separated from each other and fromV. cymbalaria, whereas the tetraploids and hexaploids are not separable morphologically.—Another poorly known diploid strain from Kurdistan is described as new:Veronica cymbalaria Bod. var.baradostensis M. Fischer.—V. panormitana is reported from Greece for the first time.  相似文献   

14.
Meredith A. Lane 《Brittonia》1996,48(4):532-541
Gundlachia, a genus of shrubs occurring in the Caribbean islands, is treated as comprising two species, one of which has six varieties. Five new combinations are made: Gundlachia corymbosa var. apiculata (Britton & S. F. Blake) M. A. Lane, G. corymbosa var. compacta (Urb. & Ekman) M. A. Lane, G. corymbosa var. cubana (Britton & S. F. Blake) M. A. Lane, G. corymbosa var. foliosa (Britton & S. F. Blake) M. A. Lane, and G. corymbosa var. ocoana (Urb. & Ekman) M. A. Lane. Gundlachia is probably most closely related to Gymnosperma.  相似文献   

15.
Ditrichum austrogeorgicum (Card.) Seppelt, a species originally described in 1906 from South Georgia as Pseudodistichium austrogeorgicum Card., is considered to be conspecific with Ditrichum hyalinum (Mitt.) O. Kuntze. The latter had been first described in 1859 as Leptotrichum hyalinum Mitt. from material collected on the Falkland Islands and Hermite Island near Cape Horn, but it had been first recognized as a separate taxon, Didymodon longifolius (Brid.) Hook. f. & Wils. var. tenuifolius Hook. f. & Wils., in 1847. Pseudodistichium austrogeorgicum f. brevifolium Card. and P. austrogeorgicum var. longifolium Broth. in Card. & Broth. are reduced to synonymy with Ditrichum hyalinum. Some details of the type material of the last are illustrated.  相似文献   

16.
红花玉兰与玉兰亚属几个种亲缘关系的AFLP分析   总被引:1,自引:0,他引:1  
贺随超  马履一 《植物研究》2008,28(3):288-292
应用AFLP分子标记技术对红花玉兰与玉兰亚属几个种之间的亲缘关系,以及红花玉兰的分类地位进行了分析。9对引物对7个玉兰种的36个代表样株进行选择性扩增,共得到扩增谱带874条,其中多态性谱带635条。分析结果表明:各玉兰种间,红花玉兰与白玉兰、武当木兰的遗传相似度较高;玉兰亚属种间基于AFLP分析的聚类结果与形态学对种的划分基本吻合。红花玉兰不仅形态上与其它玉兰种有明显区别,AFLP分子标记也支持红花玉兰为一个独立的新种,多瓣红花玉兰变种与红花玉兰原变种为一个种。  相似文献   

17.
Tod F. Stuessy 《Brittonia》1971,23(2):177-190
The white-rayed species complex ofMelampodium has been treated by various authors as containing one, two, or three species. A re-evaluation of the taxa in this complex by use of Chromatographic profiles of methanolic leaf extracts from numerous populations over the range of the group has revealed three distinct patterns which, along with morphological and ecological data, provide support for the recognition of three species within the group. Distributional analysis of previously and newly reported chromosome counts of 157 plants in 99 populations shows tetraploid races ofn = 20 in bothM. leucanthum var.leucanthum andM. cinereum var.cinereum to be located primarily in central and south central Texas but locally intermixed with diploid races. Interpretation of morphology, meiotic configurations, and chemical profiles confirms that these cytotypes are autopolyploid in origin and should not be given formal recognition. All data are used to interpret evolutionary relationships, and it is believed thatM. leucanthum var.argopkyllum may closely resemble the progenitor of the entire complex.  相似文献   

18.
We evaluated the ploidy levels and tissue culture responses of 16 Japanese Miscanthus accessions, which are registered and vegetatively maintained in the National Agriculture and Food Research Organization GeneBank, Japan, to screen suitable genotypes for the molecular breeding of Miscanthus species. A ploidy analysis showed that most M. sinensis and M. sinensis var. condensatus (var. condensatus) were putative diploids, but one accession identified as M. sinensis was unexpectedly a putative tetraploid. Additionally, M. sacchariflorus and its hybrid accessions were putative tetraploids. The deoxyribonucleic acid levels in var. condensatus were significantly higher than those in the diploid M. sinensis. Of the accessions, 10, including M. sinensis and var. condensatus, could induce plant regenerable embryogenic calli from apical meristems. We selected three of these M. sinensis accessions for further experiments because their calli growth rates were faster than those of the var. condensatus accessions. Tissue culture experiments with the selected accessions indicated that the frequencies of callus and green shoot formation strongly correlated with genotype. The broad-sense heritabilities of the embryogenic callus and green shoot formation frequencies in the selected accessions were 0.75 and 0.65, respectively, indicating that the cultures’ responses were mainly controlled by genetic factors. Thus, we further selected one accession that had the highest efficiencies in callus and green shoot formation, and we observed that light during callus culturing significantly inhibited calli growth, but promoted plant regeneration from calli in the selected accession.  相似文献   

19.
Dion edule is distributed through the Sierra Madre Oriental from Veracruz to Nuevo León and in dijunct stations in Tamaulipas. The most significant variation consists in the reduction of leaflet width from the south northwards. On this basis, two varieties are recognized:D. edule var.edule, characterized by wide leaflets and a distribution in Veracruz, Hidalgo, Querétaro, San Luis Potosí and southern Tamaulipas, andD. edule var.angustifolium, with narrow leaflets and a distribution in central-northern Tamaulipas and Nuevo León.  相似文献   

20.
Coreopsis mutica is a highly variable species occurring in the highlands from Central Mexico southeastward barely into El Salvador and Honduras. It is not continuous over this range, however, but is found in three geographic population centers: one in Guatemala and Chiapas, a second in Oaxaca, and the third in Central Mexico. Populations in Guatemala and Chiapas are uniform in chromosome number (2n = 56), leaf flavonoid chemistry, and morphology. Var.microcephala is proposed to accommodate these assemblages. Plants comprising populations centered around Cd. Oaxaca have a chromosome number of 2n = ca. 112. This large complex consists of two distinct varieties and their putative hybrids. Those plants to the northwest of Cd. Oaxaca (var.subvillosa) are constant in leaf flavonoid chemistry (producing only flavones) and possess a combination of distinctive morphological traits. To the southeast of Cd. Oaxaca plants invariably contain flavonols and anthochlors in their leaves in addition to flavones. Moreover, these plants (the newly proposed var.carnosijolia) are readily separable from var.subvillosa by a number of morphological features. Evidence is presented that the two taxa hybridize in the vicinity of Cd. Oaxaca. On the southeastern edge of the var.subvittosavar. carnosifolia complex a population was encountered which has a chromosome number of 2n = 56 and a very distinctive morphology and flavonoid chemistry. These plants have been accorded taxonomic status as var.multiligulata. Two morphologically similar, yet distinguishable, varieties occur in Central Mexico. It has been determined that the two differ also in chromosome number and leaf flavonoid chemistry. One taxon (var.leptomera) has a chromosome complement of 2n = 56 and produces only flavones in its leaves, whereas var.mutica has a chromosome number of 2n = ca. 112 and produces flavones, flavonols, and anthochlors.  相似文献   

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