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1.
An aberrant species of the genus Asteriscus (Asteraceae–Inuleae), A. pinifolius from SW Morocco, is here proposed to be removed and placed in a separate, monotypic genus Ighermia. The systematic position and morphology of the new genus are also discussed.  相似文献   

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The ability to withstand viral predation is critical for survival of most microbes. Accordingly, a plethora of phage resistance systems has been identified in bacterial genomes (Labrie et al, 2010 ), including restriction‐modification systems (R‐M) (Tock & Dryden, 2005 ), abortive infection (Abi) (Chopin et al, 2005 ), Argonaute‐based interference (Swarts et al, 2014 ), as well as clustered regularly interspaced short palindromic repeats (CRISPR) and associated protein (Cas) adaptive immune system (CRISPR‐Cas) (Barrangou & Marraffini, 2014 ; Van der Oost et al, 2014 ). Predictably, the dark matter of bacterial genomes contains a wealth of genetic gold. A study published in this issue of The EMBO Journal by Goldfarb et al ( 2015 ) unveils bacteriophage exclusion (BREX) as a novel, widespread bacteriophage resistance system that provides innate immunity against virulent and temperate phage in bacteria.  相似文献   

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A new species, Cheilosia richterae sp. n., is described in the nominotypical subgenus, being most closely related there to Ch. annulifemur Stackelberg, 1930. Two species, Ch. sootryeni Nielsen, 1970 and Ch. rufimana (Becker, 1984), are recorded from Russia for the first time. Ch. kuznetzovae Skufjin, 1977 is recorded for the first time from the Urals and western Siberia. The subgenus Nephocheila Barkalov, 2002 is synonymized with Nephomyia Matsumura, 1916. Figures of the male and female heads and the male genitalia are given for all the species.  相似文献   

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报道了产自云南麻栗坡的兰科兰属一新杂种——麻栗坡长叶兰(Cymbidium×malipoense L.J.Chen,H.B.Zhou&Z.J.Liu),对该种的形态特征进行了描述。该种可能是长叶兰(Cymbidium erythraeum Lindl.)与龙州兰(C.eburneum var.longzhouense Z.J.Liu et S.C.Chen)的天然杂交种。本种与长叶兰的区别是:本种的花葶自叶腋发出;萼片和花瓣浅黄绿色,具浅紫红色的纵条纹和斑点;唇盘具黄色褶片;蕊柱浅紫红色;中裂片卵状肾形。长叶兰的萼片和花瓣绿色,有红褐色脉纹和不规则斑点;中裂片心形到剑形;唇盘密被毛。本种与龙州兰的区别是:本种萼片和花瓣浅黄绿色,具浅紫红色的纵条纹和斑点;侧裂片有紫红色条纹;蕊柱浅紫红色。龙州兰萼片和花瓣白色,外表面略带粉红色;唇瓣白色,侧裂片和中裂片具有紫红色斑点。  相似文献   

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An extensive survey of the standing genetic variation in natural populations is among the priority steps in developing a species into a model system. In recent years, green foxtail (Setaria viridis), along with its domesticated form foxtail millet (S. italica), has rapidly become a promising new model system for C4 grasses and bioenergy crops, due to its rapid life cycle, large amount of seed production and small diploid genome, among other characters. However, remarkably little is known about the genetic diversity in natural populations of this species. In this study, we survey the genetic diversity of a worldwide sample of more than 200 S. viridis accessions, using the genotyping‐by‐sequencing technique. Two distinct genetic groups in S. viridis and a third group resembling S. italica were identified, with considerable admixture among the three groups. We find the genetic variation of North American S. viridis correlates with both geography and climate and is representative of the total genetic diversity in this species. This pattern may reflect several introduction/dispersal events of S. viridis into North America. We also modelled demographic history and show signal of recent population decline in one subgroup. Finally, we show linkage disequilibrium decay is rapid (<45 kb) in our total sample and slow in genetic subgroups. These results together provide an in‐depth understanding of the pattern of genetic diversity of this new model species on a broad geographic scale. They also provide key guidelines for on‐going and future work including germplasm preservation, local adaptation, crossing designs and genomewide association studies.  相似文献   

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《Mycoscience》2014,55(2):144-148
A new genus Verrucocephalum is proposed for a fungus which was found from bat dung collected in a limestone cave. The type species, V. latericorvinisporum has darkly pigmented spores and aseptic hyphae that branch and capture nematodes by means of appressoria. These morphological characteristics match the definition for the family Helicocephalidaceae (Zoopagales, Zoopagomycotina). The genus can be distinguished from three previously known genera in the family by its broad-based tapering sporophores with darkly pigmented verrucose spores born on short lateral branchlets. The branchlets may be homologous to the papillae seen in genus Rhopalomyces.  相似文献   

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The behaviour of Badis badis is similar, in general, both to that of "nandid" fishes and that of anabantoid fishes; trenchant differences also exist. It is impossible at this time, on behavioural evidence alone, to assess the relative importance of the behavioural findings. However, the remarkable and consistent agreement in the performance of the spawning embrace suggests a close relationship of Badis to anabantoid fishes rather than to the "nandids".
The osteological studies confirm this hypothesis. Badis apparently split off from the ancestral anabantoids before they acquired the air-breathing adaptation. The osteological differences between Badis and the anabantoids stem chiefly from the modifications accompanying aerial respiration.
The egg of Badis badisis enclosed in an unusually tough sheath that is extremely adhesive. The egg itself lacks any special device for attaching. The larva has an adhesive organ at the tip of the yolk sac. The egg and the larva of Badis badis are thus unique among teleosts insofar as is known.
From these three lines of information we erect a new percoid family, Badidae, based on Badis Bleeker. This family appears to have descended from the proto-anabantoid stock.  相似文献   

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《Ibis》1890,32(2):246-247
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Skippers of the tribe Baorini are evidently a monophyletic group in the subfamily Hesperiinae. In this study, a new Baorini member Tsukiyamaia albimacula gen. n. et sp. n. is described from north Myanmar, southwest China and north Vietnam. Despite its peculiar and striking wing-pattern, this new genus has some important characters of Baorini, such as a broad and bifid uncus and a well-developed gnathos. Based on an analysis of male genitalia and the molecular phylogenies inferred from both mitochondrial and nuclear genes (28 taxa, total aligned length: 2968 bp), it is proposed that the genus Tsukiyamaia is closely related to the genus Polytremis, which has high species diversity in China. This study not only describes a new skipper but also highlights that Tsukiyamaia is important in clarifying phylogenetic relationship of Polytremis and its allies.  相似文献   

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A new oxytrichid ciliate Notohymena saprai sp. nov was isolated from the Valley of Flowers, an isolated bioreserve in the upper Himalayas. The ciliate was found in the soil samples collected from the peripheral areas of the flowering region of the valley which is covered with permafrost for nearly eight months in a year. Cells were excysted from the soil samples by the non-flooded petridish method. Species identification was performed by observations on live and silver-impregnated cells. Notohymena saprai sp. nov is highly flexible, measures 152 × 49 μm and shows abundant presence of dark green sub-pellicular granules. The species is distinct by virtue of its new combination of morphometric and developmental characters. Prominent distinguishing features of the new species are its relative large size and presence of four macronuclei (other species of this genus have two macronuclei). The study also reports morphogenetic peculiarities which separate it from the other known species of the genus.  相似文献   

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A new species Garcinia dhanìkharíensis (Clusiaceae) from South Andaman, India is described and illustrated.  相似文献   

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Three new species of Dahlstedtia, D. burkartii, D. dehiscens, and D. lewisiana, are described from South America, and their relationships with related species are discussed. Dahlstedtia burkartii, from Argentina, has pink flowers with standard straight, whereas D. dehiscens and D. lewisiana, both from Brazil, have purplish to lilac flowers with a reflexed standard petal. A new combination, Dahlstedtia peckoltii, is proposed based on Lonchocarpus peckoltii and a neotype is selected for the latter. Information about geographic distribution and phenology of the species is provided.  相似文献   

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Six species of the genus Mocyta Mulsant & Rey are reported from Canada: Mocyta amblystegii (Brundin), Mocyta breviuscula (Mäklin), Mocyta discreta (Casey), Mocyta fungi (Gravenhorst), Mocyta luteola (Erichson), and Mocyta sphagnorum Klimaszewski & Webster, sp. n. New provincial and state records include: Mocyta breviuscula – Saskatchewan and Oregon; Mocyta discreta – Quebec, Ontario and Saskatchewan; Mocyta luteola – New Brunswick, Quebec, Ontario, Massachusetts and Minnesota; and Mocyta fungi – Saskatchewan. Mocyta sphagnorum is described from eastern Canada from specimens captured in Newfoundland, New Brunswick, Quebec and Ontario. Mocyta negligens Mulsant and Rey, a native European species suspected of occurring in Canada, is excluded from the Nearctic fauna based on comparison of European types with similarly coloured Canadian specimens, which are now identified as Mocyta luteola. The European species, Mocyta gilvicollis (Scheerpeltz), is synonymized with another European nominal species, Mocyta negligens, based on examination of type material of the two species. Lectotypes are designated for Eurypronota discreta Casey, Atheta gilvicollis Scheerpeltz, Homalota luteola Erichson, Colpodota negligens Mulsant and Rey, Acrotona prudens Casey and Dolosota redundans Casey. The latter species is here synonymized with Mocyta luteola. A review of the six Nearctic species is provided, including keys to species and closely related genera, colour habitus images, images of genitalia, biological information and maps of their distributions in Canada.  相似文献   

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