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1.
The Australian species of the genus Trigonopterus Fauvel are revised. Eight previously recognized species are redescribed and 24 additional new species are described: Trigonopterus allaetus Riedel, sp. n., Trigonopterus athertonensis Riedel, sp. n., Trigonopterus australinasutus Riedel, sp. n., Trigonopterus australis Riedel, sp. n., Trigonopterus bisignatus Riedel, sp. n., Trigonopterus bisinuatus Riedel, sp. n., Trigonopterus boolbunensis Riedel, sp. n., Trigonopterus cooktownensis Riedel, sp. n., Trigonopterus daintreensis Riedel, sp. n., Trigonopterus deplanatus Riedel, sp. n., Trigonopterus finniganensis Riedel, sp. n., Trigonopterus fraterculus Riedel, sp. n., Trigonopterus garradungensis Riedel, sp. n., Trigonopterus hasenpuschi Riedel, sp. n., Trigonopterus hartleyensis Riedel, sp. n., Trigonopterus kurandensis Riedel, sp. n., Trigonopterus lewisensis Riedel, sp. n., Trigonopterus montanus Riedel, sp. n., Trigonopterus monteithi Riedel, sp. n., Trigonopterus mossmanensis Riedel, sp. n., Trigonopterus oberprieleri Riedel, sp. n., Trigonopterus robertsi Riedel, sp. n., Trigonopterus terraereginae Riedel, sp. n., Trigonopterus yorkensis Riedel, sp. n.. All new species are authored by the taxonomist-in-charge, Alexander Riedel. Lectotypes are designated for the following names: Idotasia aequalis Pascoe, Idotasia albidosparsa Lea, Idotasia evanida Pascoe, Idotasia laeta Lea, Idotasia rostralis Lea, Idotasia sculptirostris Lea, Idotasia squamosa Lea. A new combination of the name Idotasia striatipennis Lea is proposed: Trigonopterus striatipennis (Lea), comb. n.. A key to the species is provided. Australian Trigonopterus occur in coastal Queensland, narrowly crossing into New South Wales. The southern parts of the range are inhabited by species found on foliage. A rich fauna of 19 edaphic species inhabiting the leaf litter of tropical forests is reported for the first time from the Australian Wet Tropics.  相似文献   

2.
The two membrane-bound respiratory nitrate reductases of Escherichia coli are encoded by distinct operons at two different loci, chlC and chlZ, on the chromosome. The chlZ locus includes a narK homologue, narU, encoding a nitrite extrusion protein, and narZYWV encoding nitrate reductase Z. No apparent homologue to the narXL operon has been found. Homology between narU and narK on the one hand and narZYWV and narGHJI on the other hand is limited to the coding regions.  相似文献   

3.
Many species in the families of Rosaceae, Solanaceae, and Scrophulariaceae exhibit gametophytic self-incompatibility, a phenomenon controlled by two polymorphic genes at the S-locus, style-S (S-RNase) and pollen-S (SFB). Sequences of both genes show high levels of diversity, characteristic of genes involved in recognition of self-incompatibility systems in plants. In this study, S 24 -RNase and SFB 24 alleles were cloned from Prunus armeniaca cv. Chuanzhihong (Chinese apricot). Sequence comparisons of deduced amino acid sequences revealed that the P. armeniaca S 24 -haplotype has different SFB alleles, but shares a single S-RNase allele with P. armeniaca S 4 -haplotype. Moreover, P. armeniaca S 24 -RNase haplotype has a single and three different alleles with S 1 -RNase of P. tenella (dwarf almond) and S 1 -RNase of P. mira (smooth pit peach), respectively. The functionalities of SFB 24 and SFB 4 have been evaluated by pollen tube growth and controlled field tests of P. tenella and P. mira. Genetic analysis of the two intercrosses showed that progenies segregated 1:1 into two S-genotype classes, which is consistent with the expected ratio for semi-compatibility. These findings imply that the allelic function of the S 24 -haplotype is identical to that of the S 4 -haplotype in a self-incompatibility reaction. Thus, these two Prunus S-haplotypes are in fact two neutral variants of the same S-haplotype. The evolution of the S-allele is also discussed in terms of both functions and differences between S 24 - and S 4 -haplotypes in Prunus.  相似文献   

4.
The structure of the anode space charge sheath of a vacuum arc is studied with allowance for the dependence of the negative anode fall on the ratio of the directed electron velocity v 0 to the electron thermal velocity v T for different values of the flux density of atoms evaporated from the anode. Poisson’s equation for the sheath potential is solved taking into account the electron space charge, fast cathode ions, and slow ions produced due to the ionization of atoms evaporated from the anode. The kinetic equation for atoms and slow anode ions is solved with allowance for ionization in the collision integral. Analytic solutions for the velocity distribution functions of atoms and slow ions and the density of slow ions are obtained. It is shown that the flux of slow ions substantially affects the spatial distribution of the electric field E(z) in the sheath. As the flux density increases, the nonmonotonic dependence E(z) transforms into a monotonic one and the sheath narrows. For a given flux of evaporated atoms Πa, the increase in the ratio of the directed electron velocity to the electron thermal velocity leads again to a nonmonotonic dependence E(z). As z increases, the electric field first increases, passes through the maximum, decreases, passes through the minimum E min, and then again increases toward the anode. There is a limiting value of the ratio (v 0/v T )* at which E min(z) vanishes. At v 0/v T > (v 0/V T )*, the condition for the existence of a steady-state sheath is violated and the profiles of the field and potential in the sheath become oscillating. The dependence of (v 0/v T )* on the flux density of evaporated atoms Π a is obtained. It is shown that the domain of existence of steady-state solutions in the sheath broadens with increasing Π a .  相似文献   

5.
The Pseudoroegneria species are perennial grasses in the Triticeae tribe, whose St genome has been linked to several important polyploid species. Due to frequent hybridization and complex genetic mechanism, the relationships within Pseudoroegneria, and within the Triticeae have been heavily disputed. Using the chloroplast rbcL gene we estimated the nucleotide diversity of 8 Pseudoroegneria species. We also examined the phylogenetic relationships within Pseudoroegneria and of Pseudoroegneria within the Triticeae. The estimates of nucleotide diversity indicated that Pseudoroegneria tauri and Pseudoroegneria spicata species had the highest diversity, while Pseudoroegneria gracillima had the lowest diversity. The phylogenetic analysis of Pseudoroegneria placed all P. spicata species into a clade separate from the other Pseudoroegneria species, while the relationship of the other Pseudoroegneria species could not be determined. Due to the groupings of Pseudoroegneria with the polyploid Elymus, our results strongly supported Pseudoroegneria as the maternal genome donor to Elymus. There was also weak support that P. spicata may be the maternal donor to the StH Elymus species.  相似文献   

6.
Michel Sartori 《ZooKeys》2014,(445):97-106
The type material of Epeorella borneonia Ulmer, 1939, the sole species of the genus Epeorella Ulmer, 1939 is reinvestigated and a lectotype (male imago) is designated. Based on several morphological structures, the synonymy with Epeorus Eaton, 1881 (Rhithrogeninae) is rejected. Epeorella stat. prop., known only at the winged stages, belongs to the subfamily Ecdyonurinae, and is a probable endemic of the island of Borneo. The newly erected genus Darthus Webb & McCafferty, 2007, also endemic to Borneo and only known by one species at the nymphal stage, is shown to be a junior subjective synonym of Epeorella. The new combination Epeorella vadora (Webb & McCafferty, 2007) is proposed for the species. The distribution of known heptageniid species from the Sunda Islands is discussed.  相似文献   

7.
The Australian species of the sphecid wasp genus Sphex are revised. Thirty-five species are recognized, of which 11 are new: Sphex argentatissimus, Sphex brevipetiolus, Sphex caelebs, Sphex corporosus, Sphex flammeus, Sphex fortunatus, Sphex gracilis, Sphex imporcatus, Sphex jucundus, Sphex latilobus and Sphex pretiosus. A dichotomous key covering all Australian species of the genus has been generated. The geographic distribution of all species is discussed based on all available locality records in relation to the Australian climate zones.  相似文献   

8.
9.
To infer the phylogenetic relationships of Xylaria species associated with termite nests within the genus Xylaria and among genera of the subfamily Xylarioideae, β-tubulin, RPB2, and α-actin sequences of 131 cultures of 114 species from Xylaria and 11 other genera of the subfamily were analyzed. These 11 genera included Astrocystis, Amphirosellinia, Discoxylaria, Entoleuca, Euepixylon, Kretzschmaria, Nemania, Podosordaria, Poronia, Rosellinia, and Stilbohypoxylon. We showed that Xylaria species were distributed among three major clades, TE, HY, and PO, with clade TE—an equivalent of the subgenus Pseudoxylaria—encompassing exclusively those species associated with termite nests and the other two clades containing those associated with substrates other than termite nests. Xylaria appears to be a paraphyletic genus, with most of the 11 genera submerged within it. Podosordaria and Poronia, which formed a distinct clade, apparently diverged from Xylaria and the other genera early. Species of Entoleuca, Euepixylon, Nemania, and Rosellinia constituted clade NR, a major clade sister to clade PO, while those of Kretzschmaria were inserted within clade HY and those of Astrocystis, Amphirosellinia, Discoxylaria, and Stilbohypoxylon were within clade PO.  相似文献   

10.
Karyotypic formulae of theScorzonera L. species are as follows:S. purpurea L.: K (2n)=14=8 Am+6 Bsm and K (2n)=14+1=9 Am+6 Bsm;S. austriaca Willd.: K (2n)=14=6 Am+6 Bsm+2 Cst;S. humilis L.: K (2n)=14=12 Am+2 Bsm;S. parviflora Jacq.: K (2n)=14=10 Am+4 Bsm;S. hispanica L.: K (2n)=12 Am+2 Bsm. The results of the study of the karyotypes of the generaScorzonera L.,Tragopogon L. andPodospermum DC. are summarized.  相似文献   

11.
The genetic relationships and diversity within the European and Asiatic Buxus species were analysed using AFLP, genome size analysis and chromosome counts. Based on these results two major clusters could be defined. One genetic cluster contained B. sempervirens and B. balearica, European species, and B. colchica, an Asiatic species but with leaf morphology similar to B. sempervirens. Species in this cluster were characterised by a genome size between 1.38 and 1.69?pg?2C?1 and a chromosome number of 2n?=?2x?=?28 (diploid). Only four B. sempervirens cultivars within this cluster were triploid. A second cluster contained the Asiatic Buxus species B. microphylla, B. harlandii, B. hyrcana, B. myrica, B. henryi, B. bodinieri and B. wallichiana. Within this second genetic cluster three different ploidy levels could be observed. B. harlandii, B. hyrcana and nine B. microphylla cultivars were tetraploid (2n?=?4x?=?56) with a genome size of >2.5?pg?2C?1. Fifteen other B. microphylla cultivars were triploid (2n?=?3x?=?42). The other Asiatic Buxus species, B. henryi, B. bodinieri and eight B. microphylla cultivars, were diploid with a genome size of ca. 1.5?pg?2C?1.  相似文献   

12.
13.
Multivariate analysis of both endocarp and leaf morphometrics is combined with cluster analysis and Bayesian inference of AFLP markers to assess the morphologic and genetic variation of five European members of Prunus section Prunus (P. cerasifera, P. domestica, P. insititia, P. spinosa, and P. × fruticans). Endocarp morphometrics separate most Prunus taxa studied, but overlap remains between P. domestica and P. cerasifera, and P. spinosa and P. × fruticans. Leaf morphometrics yield better separation of P. domestica and P. cerasifera, but do not allow distinction between P. spinosa and P. × fruticans. Both cluster analysis and PCoA of AFLP markers equally produce three distinct clusters. A first consists of all P. cerasifera samples and the sole P. cocomilia; a second cluster includes all individuals of P. domestica and P. insititia; and a third group comprises all P. spinosa and P. × fruticans samples.  相似文献   

14.
The Arabidopsis fruit mainly consists of a mature ovary that shows three well defined territories that are pattern elements along the mediolateral axis: the replum, located at the medial plane of the flower, and the valve and the valve margin, both of lateral nature. JAG/FIL activity, which includes the combined functions of JAGGED (JAG), FILAMENTOUS FLOWER (FIL), and YABBY3 (YAB3), contributes to the formation of the two lateral pattern elements, whereas the cooperating genes BREVIPEDICELLUS (BP) and REPLUMLESS (RPL) promote replum development. A recent model to explain pattern formation along the mediolateral axis hypothesizes that JAG/FIL activity and BP/RPL function as antagonistic lateral and medial factors, respectively, which tend to repress each other. In this work, we demonstrate the existence of mutual exclusion mechanisms between both kinds of factors, and how this determines the formation and size of the three territories. Medial factors autonomously constrain lateral factors so that they only express outside the replum, and lateral factors negatively regulate the medially expressed BP gene in a non-autonomous fashion to ensure correct replum development. We also have found that ASYMMETRIC LEAVES1 (AS1), previously shown to repress BP both in leaves and ovaries, collaborates with JAG/FIL activity, preventing its repression by BP and showing synergistic interactions with JAG/FIL activity genes. Therefore AS gene function (the function of the interacting genes AS1 and AS2) has been incorporated in the model as a new lateral factor. Our model of antagonistic factors provides explanation for mutant fruit phenotypes in Arabidopsis and also may help to understand natural variation of fruit shape in Brassicaceae and other species, since subtle changes in gene expression may cause conspicuous changes in the size of the different tissue types.  相似文献   

15.
The base of the Furongian Series in the Sino-Korean Block has not been clearly defined due to the lack of the index taxon, Glyptagnostus reticulatus. The Sesong Formation of the Taebaek Group, Taebaeksan Basin, Korea, has been known to range from the Guzhangian Stage of the Cambrian Series 3 to the middle Furongian Series, hence embracing the base of the Furongian Series. Silicified polymerid trilobites were recovered from the middle part of the Sesong Formation. Described are a total of 18 polymerid species of 13 genera: Neodrepanura sp. 1, Teinistion sp. 1, Huzhuia sp. 1, Huzhuia sp. 2, Liostracina simesi, Liostracina sp. 1, Parachangshania monkei, Parachangshania rectangularis nov. sp., Placosema bigranulosum, Fenghuangella laevis nov. sp., Baikadamaspis jikdongensis nov. sp., Baikadamaspis sp. 1, Prochuangia mansuyi, Maladioides coreanicus, Alataspis sesongensis nov. gen., nov. sp., Chuangia sp. 1, and ceratopygids genus and species indeterminate 1 and 2. The stratigraphic occurrence of these trilobites provides a basis for recognition of five zones across the base of the Furongian Series (in ascending order): the Neodrepanura, Liostracina simesi, Fenghuangella laevis, Prochuangia mansuyi, and Chuangia zones. The Neodrepanura and Chuangia zones are provisionally adopted from the previous biostratigraphic scheme, while the three other ones are newly proposed. The recommended base of the Furongian Series in the Taebaek Group of Korea coincides with the base of the Fenghuangella laevis Zone, which appears to represent an episode of profound trilobite faunal turnover.  相似文献   

16.
Forty-two samples of Sideritis species (Sideritis scardica, Sideritis raeseri, Sideritis syriaca, Sideritis taurica and Sideritis lanata) from the Balkan Peninsula were evaluated for their polyphenolic profiles in order to establish a correlation between the taxonomy, geographical location and nature and content of phenolic compounds.Eight compounds were detected in all analyzed Sideritis samples: 5-caffeoylquinic acid, lavandulifolioside, verbascoside, isoscutellarein 7-O-allosyl(1→2)glucoside, hypolaetin 7-O-[6‴-O-acetyl]-allosyl(1→2)glucoside, isoscutellarein 7-O-[6‴-O-acetyl]-allosyl(1→2)glucoside, 3′-O-methylhypolaetin 7-O-[6‴-O-acetyl]-allosyl(1→2)glucoside and 4′-O-methylhypolaetin 7-O-[6‴-O-acetyl]-allosyl-(1→2)-[6″-O-acetyl]-glucoside). They present from 50 to 80% of total phenolic content in S. scardica, S. raeseri, S. syriaca and S. taurica and up to 90% in S. lanata and the similarity of their polyphenolic profiles implies that they are systematically very closely related.Based on their polyphenolic patterns, very good differentiation between the samples of S. lanata (sect. Hesiodia) and S. scardica, S. syriaca and S. raeseri (sect. Empedoclia) was observed, that is mainly due to the very high content of 5-cafeoylquinic acid and very low amount of phenylethanoid glycosides and flavonoid glycosides.The obtained results demonstrate considerable degree of similarity between S. scardica, S. raeseri and Bulgarian S. syriaca that give contribution to the dilemma that Bulgarian S. syriaca is very similar to Turkish S. taurica and suggest further verification of its taxonomic status.  相似文献   

17.
FOF1 ATP synthases are rotary nanomotors that couple proton translocation across biological membranes to the synthesis/hydrolysis of ATP. During catalysis, the peripheral stalk, composed of two b subunits and subunit δ in Escherichia coli, counteracts the torque generated by the rotation of the central stalk. Here we characterize individual interactions of the b subunits within the stator by use of monoclonal antibodies and nearest neighbor analyses via intersubunit disulfide bond formation. Antibody binding studies revealed that the C-terminal region of one of the two b subunits is principally involved in the binding of subunit δ, whereas the other one is accessible to antibody binding without impact on the function of FOF1. Individually substituted cysteine pairs suitable for disulfide cross-linking between the b subunits and the other stator subunits (b-α, b-β, b-δ, and b-a) were screened and combined with each other to discriminate between the two b subunits (i.e. bI and bII). The results show the b dimer to be located at a non-catalytic α/β cleft, with bI close to subunit α, whereas bII is proximal to subunit β. Furthermore, bI can be linked to subunit δ as well as to subunit a. Among the subcomplexes formed were a-bI-α, bII-β, α-bI-bII-β, and a-bI-δ. Taken together, the data obtained define the different positions of the two b subunits at a non-catalytic interface and imply that each b subunit has a different role in generating stability within the stator. We suggest that bI is functionally related to the single b subunit present in mitochondrial ATP synthase.  相似文献   

18.
《Mycological Research》2007,111(2):196-203
Phylogenetic analysis of Rhizopus strains based on the D1/D2 region of LSU rDNA sequences yielded a phylogram with four well-supported clades. The R. microsporus clade concurs with classification obtained by traditional methods. The R. oryzae group was found to include species of the genus Amylomyces. The traditional R. stolonifer group was divided into two well-supported clades in the phylogram, with one clade comprising R. stolonifer var. stolonifer, R. sexualis var. sexualis, and R. sexualis var. americanus and the other clade comprising taxa with recurved sporangiophores; R. reflexus, R. stolonifer var. lyococcus, and R. circinans, identifying recurved sporangiophores as an important taxonomic character. The molecular data supported the recognition of this clade at the species level: R. lyococcus (basionym: Sporotrichum lyococcum).  相似文献   

19.
The Australian harvestmen genus Megalopsalis (Neopilionidae: Enantiobuninae) is recognised as a senior synonym of the genera Spinicrus and Hypomegalopsalis, and seven new species are described in Megalopsalis: Megalopsalis suffugiens, Megalopsalis walpolensis, Megalopsalis caeruleomontium, Megalopsalis atrocidiana, Megalopsalis coronata, Megalopsalis puerilis and Megalopsalis sublucens. A morphological phylogenetic analysis of the Enantiobuninae is also conducted including the new species. Monophyly of Neopilionidae and Enantiobuninae including ‘Monoscutidae’ is corroborated, with the Australasian taxa as a possible sister clade to the South American Thrasychirus.  相似文献   

20.
Takano I  Arima K 《Genetics》1979,91(2):245-254
The possible function of the α-inc allele (an α mating-type allele that is insensitive to the function of the homothallic gene system) was investigated by means of protoplast fusion. The fusion of protoplasts prepared from haploid strains of α-inc HO HMα HMa and α ho hmα HMa gave rise mainly to nonmating clones (58 of 64 isolates) and a few clones (six of 64 isolates) showing α mating type. Thirty of the 58 nonmating clones showed the diploid cell size and 28 clones had a larger cell size. Tetrad analysis of the nonmating clones with diploid cell size indicated that they were a/α-inc diploid; the normal α allele in α/α-inc cells was preferentially switched to an a allele. This observation further indicated that the HO/ho HMα/hmα HMa/HMa genotype is effective for the conversion of the α to a and that the inconvertibility of the α-inc allele is due to the insensitivity of the mating-type allele to the functional combination of the homothallic genes. It was suspected that fusion products larger than diploid cells might have been caused by multiple fusion of protoplasts.  相似文献   

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