World Species (world + species)

Distribution by Scientific Domains
Distribution within Life Sciences

Kinds of World Species

  • new world species


  • Selected Abstracts


    A Cladistic Analysis of the New World Species of Lotus L. (Fabaceae, Loteae)

    CLADISTICS, Issue 3 2000
    Ana M. Arambarri
    The genus Lotus L. is a monophyletic group diagnosed by the possession of a standard claw with thickened infolded margin, stamens diadelphous, and the style hardened from the base. It comprises approximately 200 species distributed throughout the world. A cladistic analysis of the New World species was performed using 39 morphological and anatomical characters (29 from seed morphology and anatomy, 1 from plant habit, 1 from leaf morphology, 6 from flower morphology, and 2 from fruit morphology). Dorycnium, Edentolotus, Krokeria, and Pedrosia, of the Old World, and 28 species of the New World were considered terminal taxa. Tetragonolobus Scop. was chosen to root the cladograms and Dorycnium Mill. to reroot them. With Tetragonolobus the analysis yielded 15 equally parsimonious trees, each with a length of 74 steps, a consistency index of 0.62, and a retention index of 0.89. The 15 initial trees and the strict consensus tree defined 12 monophyletic groups. All terminal taxa form a monophyletic group diagnosed by the presence of a radicular lobe discernible to conspicuous (character 10); rim aril thick (character 13); stipules absent (character 31); and style simple and nondilated (character 36). The New World species form a monophyletic group on the basis of the seed relationship of length to width in hilar view 1.5:1 to 2:1 (character 5); micropyle linear-deltoid to bifurcate (character 19); and keel erostrate (character 33). Identical monophyletic groups were obtained when Dorycnium was used as root. These results are discussed in the context of data on cytology and morphology. [source]


    Out-of-Africa origin and dispersal-mediated diversification of the butterfly genus Junonia (Nymphalidae: Nymphalinae)

    JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 6 2007
    U. KODANDARAMAIAH
    Abstract The relative importance of dispersal and vicariance in the diversification of taxa has been much debated. Within butterflies, a few studies published so far have demonstrated vicariant patterns at the global level. We studied the historical biogeography of the genus Junonia (Nymphalidae: Nymphalinae) at the intercontinental level based on a molecular phylogeny. The genus is distributed over all major biogeographical regions of the world except the Palaearctic. We found dispersal to be the dominant process in the diversification of the genus. The genus originated and started diversifying in Africa about 20 Ma and soon after dispersed into Asia possibly through the Arabian Peninsula. From Asia, there were dispersals into Africa and Australasia, all around 5 Ma. The origin of the New World species is ambiguous; the ancestral may have dispersed from Asia via the Beringian Strait or from Africa over the Atlantic, about 3 Ma. We found no evidence for vicariance at the intercontinental scale. We argue that dispersal is as important as vicariance, if not more, in the global diversification of butterflies. [source]


    Oral susceptibility of South African Culicoides species to live-attenuated serotype-specific vaccine strains of African horse sickness virus (AHSV)

    MEDICAL AND VETERINARY ENTOMOLOGY, Issue 4 2003
    J. T. Paweska
    Abstract., The oral susceptibility of livestock-associated South African Culicoides midges (Diptera: Ceratopogonidae) to infection with the tissue culture-attenuated vaccine strains of African horse sickness virus (AHSV) currently in use is reported. Field-collected Culicoides were fed on horse blood-virus mixtures each containing one of the seven serotype-specific vaccine strains of AHSV, namely serotypes 1, 2, 3, 4, 6, 7 and 8. The mean titres of virus in the bloodmeals for the seven vaccine strains were between 6.8 and 7.6 log10TCID50/mL. All females (n = 3262) that survived 10 days extrinsic incubation (10 dEI) at 23.5°C were individually assayed in microplate BHK-21 cell cultures. In midges tested immediately after feeding, AHSV was detected in 96.1% individuals; mean virus titre was 2.0 log10TCID50/midge. After 10 dEI virus recovery rates varied in Culicoides (Avaritia) imicola Kieffer from 1% (AHSV-2) to 11% (AHSV-7) and in Culicoides (A.) bolitinos Meiswinkel from 0% (AHSV-3) to 14.6% (AHSV-2). Although our results indicate that two major field vectors C. imicola and C. bolitinos are susceptible to oral infection with vaccine strains of AHSV, the level of viral replication for most of the vaccine strains tested was below the postulated threshold (=2.5 log10TCID50/midge) for fully disseminated orbivirus infection. In this study, for the first time AHSV has been recovered after 10 dEI from six non- Avaritia livestock-associated Old World species: C. engubandei de Meillon (AHSV-4), C. magnus Colaço (AHSV-3, -4), C. zuluensis de Meillon (AHSV-2, -4), C. pycnostictus Ingram & Macfie (AHSV-2), C. bedfordi Ingram & Macfie (AHSV-7), and C. dutoiti de Meillon (AHSV-7). As little is known about the virogenesis of AHSV in the southern African species of Culicoides, the epidemiological significance of our findings in relation to the potential for transmission of current AHSV vaccine strains by Culicoides requires further assessment. [source]


    Population morphometric analysis of the tropicopolitan bug Triatoma rubrofasciata and relationships with Old World species of Triatoma: evidence of New World ancestry

    MEDICAL AND VETERINARY ENTOMOLOGY, Issue 4 2001
    J. S. Patterson
    Abstract. Quantitative analysis of morphological characters of the head was used to reconstruct the evolutionary history of the tropicopolitan bug Triatoma rubrofasciata (De Geer) (Hemiptera: Reduviidae) and seven species of Old World Triatoma. Multivariate analysis demonstrates that T. rubrofasciata and the Old World species have a high degree of similarity with Nearctic Triatoma species, particularly T. rubida (Uhler). We interpret this to imply a common ancestry for these groups. Dissemination of T. rubrofasciata and subsequent derivation of the Old World species of Triatoma is deduced to have occurred over a period of not more than 350 years. [source]


    Phylogeny and ecological radiation of New World thistles (Cirsium, Cardueae , Compositae) based on ITS and ETS rDNA sequence data

    MOLECULAR ECOLOGY, Issue 1 2003
    Dean G. Kelch
    Abstract Sequence data from a portion of the external transcribed spacer (ETS) and internal transcribed spacers (ITS-1 and ITS-2) of 18S-26S nuclear ribosomal DNA were used to resolve historical biogeography and ecology of true thistles (Cirsium, Cardueae, Compositae) in the New World. The 650 base-pair, 3, portion of the ETS examined here showed a level of variation across taxa similar to that of the ITS sequences included. A maximum-likelihood tree based on combined ETS and ITS sequences leads us to suggest that the New World species of true thistles constitute a major lineage, which in turn comprises several smaller lineages. A western North American lineage shows weak quartet-puzzling support, but includes a well-supported lineage of species endemic to the California Floristic Province. Comparisons of this Californian lineage with other neoendemic angiosperm groups of the region show that the Californian Cirsium lineage exhibits unusually high ecological diversity for a group displaying such low levels of rDNA sequence divergence across taxa. Similarly low levels of sequence divergence were found throughout the New World Cirsium lineage. These results indicate either that Cirsium underwent a rapid ecological radiation in North America, or that rDNA evolution in North American Cirsium has been highly conservative. [source]


    Atypical cutaneous leishmaniasis in two patients receiving low-dose methotrexate

    BRITISH JOURNAL OF DERMATOLOGY, Issue 4 2006
    M. Saha
    Summary Cutaneous leishmaniasis is a protozoan disease that has high morbidity. There have been increasing reports of leishmaniasis in patients with an underlying immunosuppressed state. We present two cases of cutaneous leishmaniasis caused by Old World species in patients on methotrexate therapy. We postulate that the T-cell-mediated response to leishmaniasis infection could be modulated by methotrexate and may render an immunosuppressed individual more susceptible to developing clinical disease. [source]


    A Cladistic Analysis of the New World Species of Lotus L. (Fabaceae, Loteae)

    CLADISTICS, Issue 3 2000
    Ana M. Arambarri
    The genus Lotus L. is a monophyletic group diagnosed by the possession of a standard claw with thickened infolded margin, stamens diadelphous, and the style hardened from the base. It comprises approximately 200 species distributed throughout the world. A cladistic analysis of the New World species was performed using 39 morphological and anatomical characters (29 from seed morphology and anatomy, 1 from plant habit, 1 from leaf morphology, 6 from flower morphology, and 2 from fruit morphology). Dorycnium, Edentolotus, Krokeria, and Pedrosia, of the Old World, and 28 species of the New World were considered terminal taxa. Tetragonolobus Scop. was chosen to root the cladograms and Dorycnium Mill. to reroot them. With Tetragonolobus the analysis yielded 15 equally parsimonious trees, each with a length of 74 steps, a consistency index of 0.62, and a retention index of 0.89. The 15 initial trees and the strict consensus tree defined 12 monophyletic groups. All terminal taxa form a monophyletic group diagnosed by the presence of a radicular lobe discernible to conspicuous (character 10); rim aril thick (character 13); stipules absent (character 31); and style simple and nondilated (character 36). The New World species form a monophyletic group on the basis of the seed relationship of length to width in hilar view 1.5:1 to 2:1 (character 5); micropyle linear-deltoid to bifurcate (character 19); and keel erostrate (character 33). Identical monophyletic groups were obtained when Dorycnium was used as root. These results are discussed in the context of data on cytology and morphology. [source]


    Book review: Big Science: charting the world's species

    MITTEILUNGEN AUS DEM MUSEUM FUER NATURKUNDE IN BERLIN-DEUTSCHE ENTOMOLOGISCHE ZEITSCHRIFT, Issue 2 2008
    Hannelore Hoch
    [source]