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African Species (african + species)
Selected AbstractsMolecular identification and phylogeny of East African Simulium damnosum s.l. and their relationship with West African species of the complex (Diptera: Simuliidae)INSECT MOLECULAR BIOLOGY, Issue 1 2000A. Krüger Abstract The phylogenetic relationships of East and West African members of the Simulium damnosum complex were studied by sequence analyses of the mitochondrial 16s ribosomal RNA (rRNA) gene. Results suggest that: (i) the S. damnosum complex is divided into an East and a West African clade, and (ii) S. pandanophilum and the cytoform ,Kiwira' form an East African subbranch distinct from the ,Sanje' group. In contrast to former assumptions from cytogenetic analyses, our molecular data do not support a direct relationship between the East African S. kilibanum and the West African S. squamosum. Length differences of the rDNA internal transcribed spacer 1 (ITS-1) turned out to be useful to distinguish between cytoforms. [source] The antiquity of Madagascar's grasslands and the rise of C4 grassy biomesJOURNAL OF BIOGEOGRAPHY, Issue 10 2008William J. Bond Abstract Aim, Grasslands and savannas, which make up > 75% of Madagascar's land area, have long been viewed as anthropogenically derived after people settled on the island c. 2 ka. We investigated this hypothesis and an alternative , that the grasslands are an insular example of the post-Miocene spread of C4 grassy biomes world-wide. Location, Madagascar, southern Africa, East Africa. Methods, We compared the number of C4 grass genera in Madagascar with that in southern and south-central African floras. If the grasslands are recent we would expect to find fewer species and genera in Madagascar relative to Africa and for these species and genera to have very wide distribution ranges in Madagascar. Secondly, we searched Madagascan floras for the presence of endemic plant species or genera restricted to grasslands. We also searched for evidence of a grassland specialist fauna with species endemic to Madagascar. Plant and animal species endemic to C4 grassy biomes would not be expected if these are of recent origin. Results, Madagascar has c. 88 C4 grass genera, including six endemic genera. Excluding African genera with only one or two species, Madagascar has 86.6% of southern Africa's and 89.4% of south-central Africa's grass genera. C4 grass species make up c. 4% of the flora of both Madagascar and southern Africa and species : genus ratios are similar (4.3 and 5.1, respectively). Turnover of grasses along geographical gradients follows similar patterns to those in South Africa, with Andropogoneae dominating in mesic biomes and Chlorideae in semi-arid grassy biomes. At least 16 monocot genera have grassland members, many of which are endemic to Madagascar. Woody species in frequently burnt savannas include both Madagascan endemics and African species. A different woody flora, mostly endemic, occurs in less frequently burnt grasslands in the central highlands, filling a similar successional niche to montane C4 grasslands in Africa. Diverse vertebrate and invertebrate lineages have grassland specialists, including many endemic to Madagascar (e.g. termites, ants, lizards, snakes, birds and mammals). Grassland use of the extinct fauna is poorly known but carbon isotope analysis indicates that a hippo, two giant tortoises and one extinct lemur ate C4 or CAM (crassulacean acid metabolism) plants. Main conclusions, The diversity of C4 grass lineages in Madagascar relative to that in Africa, and the presence of plant and animal species endemic to Madagascan grassy biomes, does not fit the view that these grasslands are anthropogenically derived. We suggest that grasslands invaded Madagascar after the late Miocene, part of the world-wide expansion of C4 grassy biomes. Madagascar provides an interesting test case for biogeographical analysis of how these novel biomes assembled, and the sources of the flora and fauna that now occupy them. A necessary part of such an analysis would be to establish the pre-settlement extent of the C4 grassy biomes. Carbon isotope analysis of soil organic matter would be a feasible method for doing this. [source] Dry season ecology of riverine tiger beetles in Kruger National Park, South AfricaAFRICAN JOURNAL OF ECOLOGY, Issue 2 2008Jonathan R. Mawdsley Abstract The life cycles of many African species of tiger beetles (Insecta: Coleoptera: Cicindelidae) exhibit pronounced seasonality, with adult emergence and reproductive activity closely associated with seasonal rains. Anecdotal reports have suggested that adults of certain riverine tiger beetle species may be active during the dry season near perennial water sources. To test this hypothesis, fifteen sites along three perennial rivers in Kruger National Park, South Africa, were surveyed for tiger beetles in early September, 2006. Thirteen sites yielded adult beetles, with six species represented [Chaetodera regalis (Dejean), Cylindera disjuncta (Dejean), Habrodera nilotica (Dejean), Lophyra neglecta intermediola (Horn), Lophyridia fimbriata imperatrix (Srnka), and Myriochile melancholica (Fabricius)]. Microhabitat associations of adults of all six species and ovipositional/larval substrates of five of the six species are reported, along with observations on predatory and reproductive behaviours and the possible presence of an anti-predator chemical defence in C. regalis and L. fimbriata imperatrix. Résumé Le cycle vital de nombreuses espèces de Cicindèles (colépotères) africains présente une saisonnalité prononcée, l'émergence des adultes et l'activité reproductrice étant étroitement liées aux pluies saisonnières. Quelques rapports ont suggéré que les adultes de certaines espèces riveraines de cicindèles pourraient être actives en saison sèche à proximité de sources d'eau permanentes. Pour tester cette hypothèse, on a surveillé 15 sites le long de trois rivières permanentes dans le Parc National Kruger, en Afrique du Sud, au cours du mois de septembre 2006. Treize sites abritaient des cicindèles adultes, avec six espèces représentées, (Chaetodera regalis (Dejean), Cylindera disjuncta (Dejean), Habrodera nilotica (Dejean), Lophyra neglecta intermediola (Horn), Lophyridia fimbriata imperatrix (Srnka), and Myriochile melancholica (Fabricius). On a rapporté les associations d'adultes des six espèces et les substrats oviposition/larves pour cinq des six espèces dans les microhabitats, de même que des observations sur les comportements prédateur et reproducteur et sur la présence possible d'une défense chimique anti-prédateur chez C. regalis et L. fimbriata imperatrix. [source] A new species of spitting cobra (Naja) from north-eastern Africa (Serpentes: Elapidae)JOURNAL OF ZOOLOGY, Issue 4 2003Wolfgang Wüster Abstract A new species of spitting cobra Naja nubiae sp. nov. is described from north-eastern Africa. The distinctiveness of the new species is confirmed by multivariate analysis of pattern and scalation data. Phylogenetic analysis of mitochondrial DNA sequences reveals the new species to be the sister taxon of N. pallida, but with considerable levels of sequence divergence relative to that species. The populations concerned had previously been assigned to N. pallida. The new species differs from N. pallida principally in having more than one dark band across the neck and under the throat, as well as a pair of spots under the throat. It occupies a disjunct range across Egypt, the Sudan, Chad, Niger and Eritrea, where it seems to occupy primarily relatively mesic habitats. Naja mossambica is more closely related to N. nigricollis than to N. pallida and the new species. A key to the African species of Naja is presented. [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 2003J. 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] A new species of the family Hypsipterygidae from Vietnam, with notes on the hypsipterygid fore wing venation (Heteroptera, Dipsocoromorpha)MITTEILUNGEN AUS DEM MUSEUM FUER NATURKUNDE IN BERLIN-DEUTSCHE ENTOMOLOGISCHE ZEITSCHRIFT, Issue 1 2007Dávid Rédei Abstract Hypsipteryx vasarhelyii sp. n., belonging to the small dipsocoromorphan family Hypsipterygidae previously containing only three recent and one fossil species, is described from the southern part of Vietnam. The new species was extracted from Berlese samples collected in a mixed forest of pines and broad-leaf trees. It seems to be more closely related to the two African species, H. machadoi Drake, 1961 and H. ugandensis ,tys, 1970 than to the Oriental H. ecpaglus Drake, 1961. An identification key to all known species of Hypsipterygidae is provided. The homologies of the wing venation of recent and fossil Hypsipteryx are discussed. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Chloroplast DNA Variation and Biogeography in the Genus Rorippa Scop. (Brassicaceae)PLANT BIOLOGY, Issue 1 2002W. Bleeker Abstract: Phylogenetic relationships and biogeography of 25 Rorippa species were studied using sequences of two non-coding regions of chloroplast DNA (trnL intron, trnL/F spacer). Our results indicate a close relationship between European (R. islandica ssp. islandica, R. pyrenaica) and North American (R. curvipes, R. sinuata) mountain species. The polyploid European lowland species R. amphibia, R. palustris and R. sylvestris are much younger than the mountain species and have their closest relatives in western Asia and Siberia. Different colonization routes of the southern hemisphere are discussed for Rorippa. Australasia was colonized at least twice, most likely via the Malayan route. A molecular clock approach dates the first colonization to the end of Pliocene or early Pleistocene. R. gigantea reached Australia later in the Pleistocene. Our data provide evidence for an amphitropical disjunction between the South American (R. philippiana) and North American (R. curvisiliqua) species. Long-distance dispersal via migrating birds is the most likely explanation for this intercontinental disjunction. Two of the analysed African species (R. nudiuscula, R. madagascariensis) have their closest relative (R. austriaca) in eastern Europe and western Asia. The lack of sequence divergence among these species indicates a colonization event probably not earlier than 100 000 years ago. [source] Large-scale human effects on an arid African raptor communityANIMAL CONSERVATION, Issue 5 2010J. D. Anadón Abstract In the current scenario of biodiversity crisis there is a growing need for identifying causes of changes in biodiversity at large scales. Here we assess factors driving raptor community structure in the Sahel, a region suffering a wide range of environmental degradation and a vital area for European migrant birds. Using road surveys, we estimated the effects of population size, human settlement patterns (e.g. urban vs. nomadic) and land use on the raptor community, taking into account the major natural role played by productivity. Total raptor richness values were similar to those described for other steppe regions of the world, with one super-abundant migrant species, the black kite Milvus migrans; however, richness of resident raptors was strikingly lower than expected, with most large body-size African species (both eagles and vultures) absent. Raptor richness was strongly correlated with human activities in a scale-dependent fashion. At a 25 km resolution, raptor richness was driven by habitat and productivity, with a positive response to crops. At a smaller scale, human population was positively related with wintering species richness but negatively with richness of resident ones, perhaps as a consequence of non-agricultural activities such as direct harvesting and different forms of habitat degradation (e.g. overgrazing or firewood collection). Subsistence economies in systems with low natural environmental heterogeneity and with a human population over carrying capacity, such as the Sahel, may lead to exhausted biological systems even in the absence of intensive agricultural or urban land-use changes, as shown by the deeply impoverished sedentary raptor community. Our results suggest that, because habitat and productivity seem to play a relevant role in driving species richness, climate change may have a major effect on the raptor community of the Sahel. [source] ,After Africa': the evolutionary history and systematics of the genus Charaxes Ochsenheimer (Lepidoptera: Nymphalidae) in the Indo-Pacific regionBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2010CHRIS J. MÜLLER The predominantly Afrotropical genus Charaxes is represented by 31 known species outside of Africa (excluding subgenus Polyura Billberg). We explored the biogeographic history of the genus using every known non-African species, with several African species as outgroup taxa. A phylogenetic hypothesis is proposed, based on molecular characters of the mitochondrial genes cytochrome oxidase subunit I (COI) and NADH dehydrogenase 5 (ND5), and the nuclear wingless gene. Phylogenetic analyses based on maximum parsimony and Bayesian inference of the combined dataset implies that the Indo-Pacific Charaxes form a monophyletic assemblage, with the exception of Charaxes solon Fabricius. Eight major lineages are recognized in the Indo-Pacific, here designated the solon (+African), elwesi, harmodius, amycus, mars, eurialus, latona, nitebis, and bernardus clades. Species group relationships are concordant with morphology and, based on the phylogeny, we present the first systematic appraisal and classification of all non-African species. A biogeographical analysis reveals that, after the genus originated in Africa, the evolutionary history of Charaxes in the Indo-Pacific, in particular Wallacea, may be correlated with the inferred geological and climatic history of the region. We propose that Wallacea was the area of origin of all Charaxes (excluding C. solon) occurring to the east of Wallace's [1863] Line. The earliest Indo-Pacific lineages appear to have diverged subsequent to the initial fragmentation of a palaeo-continent approximately 13 million years ago. Further diversification in Indo-Pacific Charaxes appears primarily related to climatic changes during the Pliocene and possibly as recently as the Pleistocene. Although both dispersal and vicariance have played important roles in the evolution of the genus within the region, the latter has been particularly responsible for diversification of Charaxes in Wallacea. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 457,481. [source] Floral scent of bat-pollinated species: West Africa vs. the New WorldBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2004STEFAN PETTERSSON Floral scent of seven West African bat-pollinated tree species, belonging to six families, was collected in situ from flowering individuals using headspace adsorption. The seven species shared neither any specific compounds nor any other discernible pattern in their floral scent composition. Most of the identified compounds are common in the floral scent of species pollinated by a variety of animals. Adansonia digitata (Bombacaceae) was the only African species found to have a substantial proportion of sulphur compounds in its floral scent. This feature contrasts with the sampled New World bat-pollinated plants, which frequently contain these compounds. The floral scent of Ceiba pentandra (Bombacaceae), native to both South America and Africa, contained no sulphur substances, contradicting a previous study in the New World that identified the major floral compounds as dimethyl disulphide and dimethyl trisulphide. We suggest that the differences in the floral scent of C. pentandra, including the absence of sulphur compounds in the African variety, result from the different selective regimes exerted by the Pteropotidae bats, in Africa, and Phyllostomidae bats, in the New World, that visit their flowers. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 82, 161,168. [source] Phylogeny and biogeography of Crinum L. (Amaryllidaceae) inferred from nuclear and limited plastid non-coding DNA sequencesBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2003ALAN W. MEEROW The genus Crinum L. is the only pantropical genus of the Amaryllidaceae. Phylogenetic and biogeographical analyses of nrDNA ITS and plastid trnL-F sequences for all continental groups of the genus Crinum and related African genera are presented, with the genus Amaryllis used as outgroup. ITS indicates that C. baumii is more closely related to Ammocharis and Cybistetes than to Crinum sensu stricto. Three clades are resolved in Crinum s.s. One unites a monophyletic American group with tropical and North African species. The second includes all southern African species and the Australian endemic C. flaccidum. The third includes monophyletic Madagascar, Australasian and Sino-Himalayan clades, with southern African species. The trnL-F phylogeny resolves an American and an Asian/Madagscar clade, and confirms the relationship of C. flaccidum with species endemic to southern Africa. The salverform, actinomorphic perianths of subg. Crinum appear to have evolved several times in the genus from ancestors with zygomorphic perianths (subg. Codonocrinum), thus neither subgenus is monophyletic. Biogeographical analyses place the origin of Crinum in southern Africa, as the region is optimized at all ancestral nodes in the tree topology, and in basal interior nodes of all but one of the major clades. The genus underwent three major waves of radiation corresponding to the three main clades resolved in our trees. Two entries into Australia for the genus are indicated, as are separate Sino-Himalayan and Australasian dispersal events. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 141, 349,363. [source] The phylogeny of the Pantropical genus Arrhipis Bonvouloir (Coleoptera, Eucnemidae)CLADISTICS, Issue 1 2010Lena Brüstle The phylogeny of the genus Arrhipis Bonvouloir (Coleoptera, Eucnemidae) is clarified with a cladistic analysis based on five molecular markers and morphology. Sixteen species from Africa, America, Asia, and Australia are included in the analysis. Two separate Asian clades are recovered, one of them being the sister group to a clade with the American and African species. With the exception of the continental south-east Asian species, all Gondwanan regions have monophyletic faunas. According to the present data, the continental south-east Asian fauna comprises two monophyletic groups, one of which is the sister group to African and American species. Vicariance seems to be the logical explanation for the distribution of these lignicolous beetles. © The Willi Hennig Society 2009. [source] | ||||||||||||||||||||||