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1.
Four species including two new species,Araucarioxylon pseudochoshiense sp. nov.,Taxodioxylon pseudoablertense Nishida et H. Nishida,Taxodioxylon nihongii Nishida et H. Nishida andTaxaceoxylon saghalienense sp. nov., were described from the Upper Cretaceous (Late Turonian-Santonian) of southern Saghalien. Consecutive number from the previous paper (Nishida and Nishida, 1986). Contributions from the Laboratory of Phylogenetic Botany, Chiba University No. 102. Supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture No. 59540441.  相似文献   

2.
Five species including two new species,Araucarioxylon kiiense Ogura,Taxodioxylon albertense (Penhal.) Shimakura,Cupressinoxylon cryptomerioides Stopes,Xenoxylon watarianum sp. nov. andCedroxylon shimakurae sp. nov., were described from the Upper Cretaceous (Late Turonian-Santonian) of southern Saghalien. Consecutive number from the previous paper (Nishida and Nishida, 1985). Contributions from the Laboratory of Phylogenetic Botany, Chiba University No. 100. Supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture No. 59540441.  相似文献   

3.
Described are seven species including four new to science:Matoniostipes mesozoica gen, et sp. nov.,Taxaceoxylon japonomesoziocum sp. nov.,Planoxylon tylosissimum sp. nov., andProtocedroxylon pseudo-araucarioides sp. nov. New to Japan inCupressinoxylon sachalinense which was formerly discovered in Saghalien. Anatomy of secondary wood and pith is elucidated inCycadeoidella japonica which has had little attention except for leaf base armors in the material from Hokkaido.Araucarioxylon hujinamiense is new to the locality. Contributions from the Laboratory of Phylogentic Botany, Chiba University, No. 56. Supported by a Grant in Aid of Scientific Research of Ministry of Education, No. 75144.  相似文献   

4.
中国东北辽宁省西部几种中生代化石木   总被引:5,自引:0,他引:5  
对产自辽宁省西部中生代化石木进行了解剖学研究。经鉴定,它们是:朝阳原始云杉型木(新种)(Protopiceoxylon chaoyangense Duan sp.nov.),西部南洋杉型木(Araucarioxylon sidugawaense Shimakura),巴图南洋杉型木(新种)(Araucarioxylon batuense Duan sp.nov.)和辽西紫杉型木(新种)(Taxox  相似文献   

5.
Allochthonous Lower and Middle Jurassic (Pliensbachian–Bathonian) permineralized and charcoalified woods from the Cleveland Basin (North Yorkshire, England) are assigned to five genera of gymnospermous wood ( Cupressinoxylon spp., Taxodioxylon spp., Cedroxylon spp., Xenoxylon Araucarioxylon ) and two species ( Xenoxylon phyllocladoides Araucarioxylon lindlei ). Cell structure is commonly well preserved, particularly in calcified and charcoalified samples, and several features of the growth rings have palaeoclimatological significance. These include distinct growth rings, commonly narrow latewood, low to moderate annual sensitivity and mean sensitivity values, and presence of false rings. Overall, these characteristics reflect fairly consistent growth, both during the growing season and from year to year. Temporally, there is a transition towards narrower rings of more variable width, proportionally wider latewood, and more abundant false rings in Bathonian woods. Water supply is interpreted as the primary limiting control on growth and was probably more restricted in the Bathonian. This is suggested to be a consequence of relatively low sea-level and, more importantly, a genuinely drier climate at this time, manifested as an accentuated annual dry season. In all, the increase in seasonality during the Early and Mid Jurassic in North Yorkshire is compatible with the effects of a developing Mediterranean-type climate.  相似文献   

6.
The wood flora from Williams Point, Livingston Island, contains 12 wood types of gymnosperm and angiosperm origin. Recent collections of material have increased the biodiversity of a postulated species-rich vegetation. The gymnosperm wood can be readily assigned to four form-genera: Araucarioxylon Kraus, Araucariopitys Jeffrey, Podocarpoxylon Gothan and Sahnioxylon Bose and Sah. This indicates a diversity of coniferous araucarian and podocarp trees alongside woods of uncertain affinity ( Sahnioxylon ; Bennettitales). Two angiosperm morphotypes are assigned to the organ genera Hedycaryoxylon Su¨ss (Monimiaceae) and Weinmannioxylon Petriella (Cunoniaceae). The remaining four taxa of angiosperm wood cannot be confidently placed in extant families as they exhibit features that suggest relationships with the Magnoliidae, Hamamelidae and Rosidae. This paper presents the first comprehensive taxonomic revision of the wood flora from Livingston Island and discusses the palaeoecology that prevailed at a latitude of about 60 degrees south during the Late Cretaceous. Newly described taxa are Araucarioxylon chapmanae sp. nov., Araucariopitys antarcticus sp. nov., Podocarpoxylon chapmanae sp. nov., P. verticalis sp. nov., P. communis sp. nov., Weinmannioxylon ackamoides sp. nov., Antarctoxylon livingstonensis gen. et sp. nov., A. multiseriatum gen. et sp. nov., A. heteroporosum gen. et sp. nov. and A. uniperforatum gen et sp. nov.  相似文献   

7.
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   

8.
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   

9.
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   

10.
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   

11.
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   

12.
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   

13.
The New World genus Philonome Chambers, 1874 is revised. This genus comprises twelve species, seven of which are described as new: two species, Philonome nigrescens sp. n. and Philonome wielgusi sp. n., from the United States; four species, Philonome albivittata sp. n., Philonome curvilineata sp. n., Philonome kawakitai sp. n., and Philonome lambdagrapha sp. n., from French Guiana; and one species, Philonome penerivifera sp. n., from Brazil. Lectotypes are designated for Philonome clemensella Chambers, 1874 and Philonome rivifera Meyrick, 1915. Partially on evidence of their head morphology and particularly from molecular evidence, the genus Philonome, previously associated with Bucculatricidae or Lyonetiidae, is reassigned to Tineidae. A possible systematic position of Philonome within Tineidae is discussed. Eurynome Chambers, 1875, is synonymized with Argyresthia Hübner, 1825 (Argyresthiidae). Photographs of adults and illustrations of genitalia, when available, are provided for all described species of Philonome and two species previously misplaced in Philonome, Argyresthia luteella (Chambers, 1875) and Elachista albella (Chambers, 1877). In addition, DNA barcodes were used for the delimitation of most species.  相似文献   

14.
15.
The λdv1 plasmid forms an extensive oligomeric series of circular DNA molecules in recombination-proficient (recsu+) Escherichia coli. These rec+ [λdv1]+ strains can be typed into the following four classes according to which member of the oligomeric series is most frequent: monomer, dimer, trimer, and tetramer strains. Each of these strains forms a set of circular λdv1 DNA molecules in which most members belong to the series l, 2l, 3l, 4l, where l is the length of the most frequent circular DNA that characterizes the strain—i.e. l equals the length of the most frequent oligomer in the respective strain. In a given strain, the frequency of a molecular species decreases as its length becomes a larger multiple of l. For example, the dimer strains produce dimers, tetramers, hexamers, octomers, etc., in decreasing frequencies, which reach the limits of detection at about the hexadecamer.When recA? mutations that are absolutely defective for host recombination are introduced into each of these four strains, l retains the same values as in the parent rec+ strain, but oligomers larger than 2l are not formed, and the frequency of the 2l oligomer is much reduced. The introduction of recB? or recC? mutations, which are only partially defective for host recombination, produces a much smaller perturbation of the rec+ distributions, and rec+recA? merodiploids exhibit the rec+ phenotype with respect to both oligomerization and host recombination.The effects of rec? mutations on the distribution of λdv1 oligomers and the nature of the oligomeric series produced in rec+ cells all indicate that an intermolecular reciprocal recombination between two circular λdv1 DNAs is the principal reaction responsible for oligomerization. It is suggested that the small residual oligomerization that yields 2l oligomers in recA?cells results from aberrant segregation of the DNA strands at the termination of the replication of l-sized molecules.The inactivation of recA, but not of recB or C, also results in a marked reduction in the frequency of spontaneous curing which in recA+dv1+]hosts leads to the segregation of [λdv?]cells. However, spontaneous curing does not appear to be dependent upon the recombination reactions that yield the [λdv 1+]oligomers, since the frequency of oligomerization in recA+ hosts decreases with increasing l, whereas the frequency of curing increases with increasing l.  相似文献   

16.
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   

17.
The Neotropical genus Menevia Schaus, 1928 is revised to include 18 species, 11 of which are new. Two species, Menevia ostia comb. n. and Menevia parostia comb. n. are transferred from Pamea Walker, 1855 to Menevia. Four species-groups are diagnosed for the first time based on external characters and male genitalia morphology. The following new species are described: Menevia rosea sp. n., Menevia torvamessoria sp. n., Menevia magna sp. n., Menevia menapia sp. n., Menevia mielkei sp. n., Menevia australis sp. n., Menevia vulgaris sp. n., Menevia franclemonti sp. n., Menevia vulgaricula sp. n., Menevia cordillera sp. n., and Menevia delphinus sp. n.. A neotype is designated for Mimallo plagiata Walker, 1855, which has since been placed in Menevia. Mimallo saturata Walker, 1855 is interpreted to be a nomen dubium.  相似文献   

18.
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   

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.
Two new species of the genus Zilchistrophia Weyrauch, 1960 are described from Eastern Ecuadorian rain forest: Zilchistrophia hilaryae sp. n. and Zilchistrophia shiwiarorum sp. n. These two new species extend the distribution of the genus considerably northwards, because congeners have been reported from Peru only. For the first time we present anatomical data (radula, buccal mass, morphology of the foot and the genital structure) of Zilchistrophia species. According to these, the genus belongs to the family Scolodontidae, subfamily Scolodontinae (=“Systrophiini”). The previously assumed systematic relationship of Zilchistrophia with the Asian Corillidae and Plectopylidae based on the similarly looking palatal plicae is not supported.  相似文献   

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