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1.
《Ibis》1933,75(4):745-751
T he authors of these notes are engaged upon a work to be called 'The African Handbook of Birds,' the first part of which covers that area of eastern Africa which includes the Sudan, Eritrea, Abyssinia, the Somalilands, Uganda, Kenya Colony, Tanganyika Territory, Belgian Ruanda and Urundi, the part of Nyasaland east of Lake Nyasa and the Shirté River, the part of Portuguese East Africa north of the Zambesi, and the islands adjacent to the mainland, including Socotra, Abd-el-Kuri, Pemba, and Zanzibar.  相似文献   

2.
Molecular genetic studies were carried out on three isolates of Trichinella nelsoni (from Kenya, Tanzania and South Africa) and three isolates of Trichinella T8 (from South Africa and Namibia) from sylvatic carnivores and from a sylvatic swine. A probe (pT7.3) specific for T. nelsoni was obtained by screening a pUC18 genomic library. The pT7.3 sequence was 346 bp in length with an AT content of 70%. The sequence is present approximately 200 times per haploid genome. Southern blot analysis of Hind III digested DNAs of the three isolates of T. nelsoni revealed that the hybridisation patterns of the isolates from Kenya and Tanzania were identical and that they differed from that of the isolate from South Africa, indicating the presence of polymorphism in this species. A pUC18 genomic library of Trichinella T8 was also screened, and one clone (pT8.3) was found to be specific for homologous DNA by dot blot, but Southern blot analysis of DNA samples from eight genotypes showed different hybridisation signals for both Trichinella T8 and Trichinella britovi DNAs. No differences in the nucleotide sequences of the expansion segment V were observed for the T. nelsoni isolates. However, they differed from those of Trichinella T8. The presence of Trichinella T8 in Africa south of the Sahara and its genetic relationship with T. britovi remain unclear and warrant detailed investigations.  相似文献   

3.
The monotypic genus Mombnsinia was established by the writer (De Lotto, 1964) for the inclusion of Pseudococcus pulcherrimus De Lotto, 1960; a very peculiar mealy bug collected in Mombasa, Kenya, on the underside of leaves of Flacourtia indica L. To the genus is referred here the following new species, very closely related to the type, which has recently been collected in South Africa on a host belonging to the same plant family.  相似文献   

4.
GEOGRAPHICAL VOICE-VARIATION IN AFRICAN BIRDS   总被引:1,自引:0,他引:1  
《Ibis》1948,90(1):48-71
  相似文献   

5.
Bauhinia leucantha sp. nov. is described from central Somalia. The new species is related particularly to B. ellenbeckii in Ethiopia and Somalia, B. teitensis in Kenya, and B. natalensis in eastern South Africa. B. somalensis is reduced to a synonym of B. ellenbeckii and the distribution of this species is shown to extend to northern Somalia.  相似文献   

6.
Serum samples from 526 baboons (Papio cynocephalus) from 10 troops from the Laikipia district of northern Kenya, from 60 baboons from two troops from the Awash National Park, central Ethiopia, and from 127 baboons from South Africa were tested for Gm and Inv allotypes. Four of the 10 troops from Kenya formed a western cluster and six formed an eastern cluster. The clusters were separated by approximately 10 miles. The samples were tested for Gm (1, 2, 3, 5, 6, 11, 13, 14, 15, 16, 17, 21, 24) and for Inv (1, 2, 3). All samples were negative for Gm (2, 6, 14, 16, 24). All from Kenya and Ethiopia were negative for Inv (2), and all were positive for Gm (11, 17) and for Inv (3). The south African samples differed from the others in that 10 were negative for Gm (11) and four were positive for Inv (2). Taking all animals into account, polymorphism was present for Gm (1, 3, 5, 11, 13, 15, 21) and for Inv (1, 2). No two Kenya troops had the same array of phenotypes or of haplotypes, but the four western troops were more similar to each other than to the six eastern troops. Three haplotypes were present in the eastern troops that were not present in the western troops and five were present in the western troops that were not present in the eastern troops. Five haplotypes appeared in at least some troops of each cluster of troops. The samples from each of the two troops from Ethiopia show the same three phenotypes but with significantly different frequencies. It is suggested that the variation in haplotype frequencies observed among the 10 troops from Kenya is the result of a founder effect deriving largely from fission of a large troop into two smaller troops. The data show that speculations about the evolutionary origin of the allotypes are premature. For most species, too few animals have been tested and except for those in this study their origins are not known. Finally, the samples have been from too restricted an area.  相似文献   

7.
Recently, mortalities among giraffes, attributed to infection with unique species of piroplasms were reported in South Africa. Although haemoparasites are known to occur in giraffes of Kenya, the prevalence, genetic diversity and pathogenicity of these parasites have not been investigated.In this study, blood samples from 13 giraffes in Kenya were investigated microscopically and genomic DNA extracted. PCR amplicons of the hyper-variable region 4 (V4) of Theileria spp. small subunit ribosomal RNA (18S rRNA) gene were hybridized to a panel of genus- and species-specific oligonucleotide probes by reverse line blot (RLB). Two newly designed oligonucleotide probes specific for previously identified Theileria spp. of giraffes found single infections in eight of the specimens and mixed infections in the remaining five samples.Partial 18S rRNA genes were successfully amplified from 9 samples and the PCR amplicons were cloned. A total of 28 plasmid clones representing the Kenyan isolates were analyzed in the present study and compared with those of closely-related organisms retrieved from GenBank. In agreement with RLB results, the nucleotide sequence alignment indicated the presence of mixed infections in the giraffes. In addition, sequence alignment with the obtained 18S rRNA gene sequences revealed extensive microheterogeneities within and between isolates, characterized by indels in the V4 regions and point mutations outside this region. Phylogeny with 18S rRNA gene sequences from the detected parasites and those of related organisms places Theileria of giraffes into two major groups, within which are numerous clades that include the isolates reported in South Africa. Collectively, these data suggest the existence of at least two distinct Theileria species among giraffes, and extensive genetic diversity within the two parasite groups.  相似文献   

8.
During the first half of the twentieth century, two accidental cases of introduction of Pissodes weevils were recorded from the southern hemisphere. The weevils in South Africa were identified as the deodar weevil (Pissodes nemorensis) and those in South America as the small banded pine weevil (Pissodes castaneus). Wide distribution of the two species in their invasive range, general difficulty in identifying some Pissodes spp., and the varying feeding and breeding behaviours of the species in South Africa has necessitated better evidence of species identity and genetic diversity of both species and population structure of the species in South Africa. Barcoding and the Jerry-to-Pat region of the COI gene were investigated. Morphometric data of the South African species was analysed. Our results confirmed the introduction of only one Pissodes species of North American origin to South Africa. However, this species is not P. nemorensis, but an unrecognized species of the P. strobi complex or a hybrid between P. strobi and P. nemorensis. Only P. castaneus, of European origin, was identified from South America. We identified ten mitochondrial DNA haplotypes from South Africa with evidence of moderate genetic structure among geographic populations. Terminal leader and bole-feeding weevils did not differ at the COI locus. A single haplotype was identified from populations of P. castaneus in South America. Results of the present study will have implications on quarantine, research and management of these insect species.  相似文献   

9.
Abstract Studies were conducted to assess the numerical response of ground‐dwelling arthropods to a habitat management system (‘push–pull’) developed to control maize stemborers using spiders (Araneae) as an indicator group. In this cropping system, maize is intercropped with a stemborer moth‐repellent (push) plant while an attractant trap crop (pull) is planted around this intercrop. Two study sites in western Kenya and one site at the Grain Crops Institute of the Agricultural Research Council in Potchefstroom, South Africa, were sampled. Treatments comprised a maize monocrop and an intercrop of maize and desmodium, Desmodium uncinatum Jacq., with Napier grass, Pennisetum purpureum (Schumach), as a trap crop around the field (‘push–pull’) in each site. Experiments were laid out in a completely randomized design with four replications at each site. Ground‐dwelling spiders were sampled using a combination of pitfall traps and soil samples. A total of 2175 spiders, 78 species in 18 families, were recovered in Kenya and 284 spiders, 34 species in nine families, were recovered in South Africa. Lycosidae was the most abundant family, accounting for >50% of all individual spiders and 27.6% by species richness. Spiders were significantly more abundant at the Kenyan sites than in South Africa while species diversity was significantly higher in South Africa than at the Kenyan sites. At all sites, spider abundance was significantly higher in the ‘push–pull’ than in the maize monocrop plots. However, the overall spider diversity was only significantly higher in the ‘push–pull’ than in the maize monocrop plots in South Africa. Moreover, species dominance did not differ between the two cropping systems at all sites. The results showed that the ‘push–pull’ system evidently enhances overall abundance of spiders, illustrating its potential in further pest control in the maize agroecosystems where spiders may often be one of the most important predatory groups.  相似文献   

10.
A large number of proposed biofuel crops share the same traits as known invasive plant species, many of which are already present in Africa and include species such as Prosopis glandulosa Torrey (Mimosaceae), P. juliflora (Sw.) DC, Leucaena leucocephala (Lam.) de Wit (Mimosaceae), Azadirachta indica A. Juss. (Meliaceae), and others. In this paper, we mainly assess the impacts of invasive Prosopis species in Africa, particularly in Kenya and South Africa. Introduced Prosopis species have invaded over 4 million hectares in Africa, threatening crop and pasture production, reducing underground water reserves, and displacing native plant and animal species. This has major implications for millions of people who depend on natural resources for their survival. It is therefore suggested that known invasive or potentially invasive plant species not be introduced to countries or regions for biofuel production. If (after a stringent cost–benefit analysis) the introduction of a potentially invasive species is deemed critical for economic development and the benefits clearly outweigh the potential costs, countries should endeavour to abide by the Principles and Criteria for Sustainable Biofuel Production developed by the Roundtable on Sustainable Biofuels.  相似文献   

11.
The genetic variability of whitefly (Bemisia tabaci) species, the vectors of cassava mosaic begomoviruses (CMBs) in cassava growing areas of Kenya, Tanzania, and Uganda, was investigated through comparison of partial sequences of the mitochondria cytochrome oxidase I (mtCOI) DNA in 2010/11. Two distinct species were obtained including sub‐Saharan Africa 1 (SSA1), comprising of two sub‐clades (I and II), and a South West Indian Ocean Islands (SWIO) species. Among the SSA1, sub‐clade I sequences shared a similarity of 97.8–99.7% with the published Uganda 1 genotypes, and diverged by 0.3–2.2%. A pairwise comparison of SSA1 sub‐clade II sequences revealed a similarity of 97.2–99.5% with reference southern Africa genotypes, and diverged by 0.5–2.8%. The SSA1 sub‐clade I whiteflies were widely distributed in East Africa (EA). In comparison, the SSA1 sub‐clade II whiteflies were detected for the first time in the EA region, and occurred predominantly in the coast regions of Kenya, southern and coast Tanzania. They occurred in low abundance in the Lake Victoria Basin of Tanzania and were widespread in all four regions in Uganda. The SWIO species had a sequence similarity of 97.2–97.7% with the published Reunion sequence and diverged by 2.3–2.8%. The SWIO whiteflies occurred in coast Kenya only. The sub‐Saharan Africa 2 whitefly species (Ug2) that was associated with the severe CMD pandemic in Uganda was not detected in our study.  相似文献   

12.
Hyaenas belonging to the genusPachycrocuta were the largest hyaenas known. They had a wide distribution in the Plio-Pleistocene, having been found throughout Eurasia and in South Africa. The genus has been reported several times from east Africa, but these finds have been poorly documented. I here describe newly identified specimens ofPachycrocuta from the Turkana Basin, Kenya. It is concluded that although there are certain differences between east and South African specimens, these are of a nature that can be explained by individual variation, and therefore all African specimens are assigned to the Eurasian speciesPachycrocuta brevirostris. The migration patterns of the species are discussed and although these are still equivocal, I speculate that the species originated in Asia and migrated from there to Africa ca. 3.5 Ma and to Europe ca. 1.6 Ma.  相似文献   

13.
J. S. Weir 《Hydrobiologia》1966,28(1):123-128
Summary 35 species of aquatic and semi-aquatic Hemiptera taken in ephemeral pools and pans at 21 collecting sites in 2 regions of Southern Rhodesia are recorded. Ecological conclusions on the habitat preferences of some of these species are described and comparisons are made with collections from equivalent habitats in South Africa, East Africa, Abyssinia and Arabia. Differences in alkalinity, pH and acidity have no detectable effect on the occurrence of species, but the physical conditions of the habitat appear to be critical (e.g. size, depth of pool, temperature, etc.). The majority of the aquatic Hemiptera from these temporary pools and pans are widespread Ethiopian species, e.g. Anisops pellucens, A. varia, A. debilis (Some occur also in Arabia), or are Ethiopian-Oriental species, e.g. Anisops sardea, Laccotrephes brachialis, Mesovelia vittigera and the remainder of the fauna consists of a few endemic (regionally abundant) species. Such endemics are for instance Anisops convexonota in Arabia, A. worthingtoni in Kenya, A. hancocki and A. jaczewski in East and Central Africa, A. aglaia in the Transvaal and Cape Province. It is suggested that the widespread Ethiopian species may show more complete adaptation and versatility to life in pans than regionally occurring species, and that the zoogeographic spread of Ethiopian species may be restricted in part by climatic change (e.g. temprature) and in part by the restriction of pans themselves to certain climatic regions. It would be extremely difficult to differentiate between such effects. These results are discussed in relation to recent zoogeographic studies in Africa.University College of Rhodesia and Nyasaland  相似文献   

14.
In West Africa, Trichinella infection was documented in humans and animals from Senegal in the 1960s, and the biological characters of one isolate showed a lower infectivity to domestic pigs and rodents when compared with that of a Trichinella spiralis pig isolate from Europe. To identify the Trichinella species present in West Africa, a survey was conducted in a total of 160 wild animals in the Republic of Guinea. Three Viverridae, one true civet (Viverra civetta) and two African palm civets (Nandinia binotata) from the Fouta Djallon Massif, Pilimini Subprefecture, were found positive by artificial digestion of muscle samples. Trichinella larvae from these three viverrids were identified as Trichinella britovi and no difference was detected in three examined sequences from these African isolates and the reference strain of T. britovi from Europe, indicating common ancestry, an historically continuous geographic distribution, and recent isolation for African and European populations. The detection of T. britovi in West Africa modifies our knowledge about the distribution of encapsulated species of Trichinella in Africa. Thus, Trichinella nelsoni is now considered to have a distribution limited to the Eastern part of the Afrotropical region from Kenya to South Africa. This provides a plausible explanation for the presence of Trichinella T8 in Namibia and South Africa, and further suggests that T. britovi could be the Trichinella species circulating among wild animals of Northern Africa.  相似文献   

15.
《Ibis》1950,92(4):540-544
The males of Oenanthe l. lugubris , and perhaps also the females, are dimorphic, the males having a black-bellied and a white-bellied phase. The white-bellied phase of the males from Eritrea, Abyssinia and Somaliland may be distinguished from white-bellied Oe. lugubris schalowi of the highlands of Kenya and neighbouring Tanganyika Territory by the coloration of the mantle. There is also a statistically significant size difference.  相似文献   

16.
A new genus, Aldersladum (family Alcyoniidae), is established to accommodate a previously described species, Efflatounaria sodwanae Benayahu, 1993 (family Xeniidae) from Sodwana Bay, South Africa that was wrongly assigned to the latter genus. This species is redescribed and a second new species, Aldersladum jengi from Penghu Is., Taiwan, is described. The diagnostic features of the new genus include the presence of only figure-eight shaped platelets in all parts of the colony, thus differentiating it from all known genera of the Alcyoniidae. Based on examination of additional material from other localities, the zoogeographical distribution of the genus is confirmed to include the coral reefs of South Africa, Kenya, Gulf of Oman, Taiwan and Japan. Phylogenetic analyses of two mitochondrial genes strongly support its placement in the family Alcyoniidae.  相似文献   

17.
Although grapevine is a crop that produces fruit without insect pollination, vineyards may provide resources for bees and other pollinators. Flower resources such as pollen and nectar are provided by the vine plants as well as other flowering plants including cover crops grown between the vine rows. Little is known about how management and landscape context affects bee communities in pollinator-independent crop systems such as grapevine. This study investigates the effect of organic versus conventional management on bee species richness and abundance in vineyards in Italy and South Africa both having a Mediterranean climate. In each country, six pairs of organic and conventional vineyards were studied in simplified and complex agricultural landscapes. A total of 433 bee individuals from 25 species and 1049 individuals from 15 species were recovered in pan traps from Italy and South Africa respectively. Bee abundance showed region specific response to the effects of vineyard management. Flowering plants and proportion of uncultivated land mediated differences in bee abundance. Higher flowering plant species richness and flower density were found in organic vineyards compared to conventional vineyards in South Africa but these flowering plant indices were not significantly different between the two vineyard management types in Italy. This emphasizes the necessity for local and region specific studies for informing conservation, as even in the same crop system with a similar climate, the effects of farm management differed between countries.  相似文献   

18.
The fall armyworm (FAW), Spodoptera frugiperda, is a major pest of maize in North and South America. It was first reported from Africa in 2016 and currently established as a major invasive pest of maize. A survey was conducted to explore for natural enemies of the fall armyworm in Ethiopia, Kenya and Tanzania in 2017. Smallholder maize farms were randomly selected and surveyed in the three countries. Five different species of parasitoids were recovered from fall armyworm eggs and larvae, including four within the Hymenoptera and one Dipteran. These species are new associations with FAW and were never reported before from Africa, North and South America. In Ethiopia, Cotesia icipe was the dominant larval parasitoid with parasitism ranging from 33.8% to 45.3%, while in Kenya, the tachinid fly, Palexorista zonata, was the primary parasitoid with 12.5% parasitism. Charops ater and Coccygidium luteum were the most common parasitoids in Kenya and Tanzania with parasitism ranging from 6 to 12%, and 4 to 8.3%, respectively. Although fall armyworm has rapidly spread throughout these three countries, we were encouraged to see a reasonable level of biological control in place. This study is of paramount importance in designing a biological control program for fall armyworm, either through conservation of native natural enemies or augmentative release.  相似文献   

19.
The cpDNA restriction variation in 39 populations representing a geographical sampling of 18 species of Androcymbium in southwestern and northern Africa was examined to assess the historical biogeography of the genus. The cpDNA phylogeny indicates that the disjunction between South and North Africa is best explained by the dispersal of southern African ancestors into North Africa. Divergence time estimates suggest that the geographic range of the genus may have extended considerably north (perhaps to Tanzania and Kenya) prior to the global desiccation of Africa in the Miocene. Further expansion of the genus northward was probably stalled until climatic changes in the late Miocene brought about the gradual replacement of a subtropical woodland savanna with the arid landscape that gave rise to the Sahara. Aridification of the northern quarter of the continent provided the ecological conditions for fostering the expansion of Androcymbium along the Mediterranean fringe (probably east to west) and its introduction into the Canary Islands. Unlike their South African congeners, the northern species have experienced expansions, fragmentations, and local extinctions in response to the severe climatic shifts in this area during the Pliocene-Pleistocene. According to our divergence time estimates, the arid track may have already existed as a continuous area connecting southern and northern Africa in the late Miocene.  相似文献   

20.
This study highlights the species diversity of Odonata from coastal forests in southern Kenya, identifying indicator species for certain habitat types and emphasising the importance of conserving the last remaining coastal forest areas. A total of 78 species were recorded from coastal habitats in southern Kenya in this study; five species for the first time in eastern Africa. Dragonfly communities relative to different habitat types from indigenous forest to cultivated landscapes are described and compared. The forest species are often confined to coastal forests of East Africa. They are stenotopic and highly sensitive to disturbance. With increasing habitat disturbance the species richness increases at first, but most of the colonisers are eurytopic species that are common and widely distributed in Africa. The species assemblages between different habitat types in the disturbed landscape are more or less the same; the -diversity is much lower than in different habitat types of the natural coastal landscape. In the end, management implications are briefly discussed.  相似文献   

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