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1.
N. CUMBERLIDGE 《African Journal of Ecology》1985,23(3):195-197
The West African river crab, Potamonautes (Platypotamonautes) ecorssei (Marchand, 1902) is reported to occur for the first time in Ghana and for only the second time in Nigeria. Its geographical range is extended south to include the Volta river basin in Ghana, and east to northwest Nigeria, a distance of some 1200 km. 相似文献
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L. G. Grimes 《Ibis》1974,116(2):165-171
During the northern spring of 1970 and 1971, wader departures were tracked by radar from saltpans on the coast of Ghana near Accra. All but one of the departures headed northeast, and none were directed along the coast. There was a statistically significant difference between the mean heading of April departures (28°± 10°), and May and June departures (41°± 14°). Projected on great circles, all headings were directed towards the known breeding ranges of the wader species wintering at the saltpans.
In ten species, the dates of the first returning birds to the saltpans in 1966, 1968 and 1970 were about three weeks earlier than dates recorded in Senegal. It is likely that those reaching Senegal follow a coastal route, whereas waders wintering at the coast of Ghana and eastwards to Nigeria evidently make a crossing of the Sahara both in autumn and spring. 相似文献
In ten species, the dates of the first returning birds to the saltpans in 1966, 1968 and 1970 were about three weeks earlier than dates recorded in Senegal. It is likely that those reaching Senegal follow a coastal route, whereas waders wintering at the coast of Ghana and eastwards to Nigeria evidently make a crossing of the Sahara both in autumn and spring. 相似文献
4.
A new species of the chromidotilapiine genus Thysochromis, is described from the Noumbi and Kouilou River drainages in the Republic of Congo. Based on the current investigation, Thysochromis is resolved as containing two geographically disjunct species, T. ansorgii from localities in the upper Guinean ichthyofaunal province (Ivory Coast, Ghana, Benin and Nigeria) and Thysochromis emili sp. nov. restricted to coastal regions of the Republic of Congo in the lower Guinean province. 相似文献
5.
D. I. M. Wallace 《Ibis》1973,115(4):559-571
Regular observations of sea-birds were made in the vicinity of Lagos, southwest Nigeria, between October 1967 and June 1971. Records in the Gulf of Guinea were obtained in April 1969 and, together with others from Ghana and Sierra Leone, were used to complement this study. While few large populations of sea-birds are supported, the diversity of species occurring at Lagos and over offshore deep water was great. The occurrence of nine species of sea-bird new to Nigeria was established or confirmed; most of these were also new to West Africa southeast of Gambia. Details are given of fluctuations in numbers these and a further 16 species.
All coastal habitats at Lagos supported a large population of immature Black Terns, and groups of immatures made up a high proportion of observations of other Palaearctic terns and of Royal Terns, which breed only in northwest Africa. In contrast, the Lesser Black-backed Gulls and Damara Terns reaching Lagos (from breeding grounds almost two continents apart) were mainly adults; both these species are amongst those showing a current increase in numbers. A pronounced spring passage was observed among species including Royal and Sandwich Terns, but adult movements in autumn were not elucidated. The occurrence of the European race of the Little Tern in southwest Nigeria was confirmed, it is at least a regular spring migrant. The frequency of vagrants in January and February was linked to local climate as much to general distribution. Brief comment is also given on immature plumages, and the growing exploitation and pollution of coastal waters. 相似文献
All coastal habitats at Lagos supported a large population of immature Black Terns, and groups of immatures made up a high proportion of observations of other Palaearctic terns and of Royal Terns, which breed only in northwest Africa. In contrast, the Lesser Black-backed Gulls and Damara Terns reaching Lagos (from breeding grounds almost two continents apart) were mainly adults; both these species are amongst those showing a current increase in numbers. A pronounced spring passage was observed among species including Royal and Sandwich Terns, but adult movements in autumn were not elucidated. The occurrence of the European race of the Little Tern in southwest Nigeria was confirmed, it is at least a regular spring migrant. The frequency of vagrants in January and February was linked to local climate as much to general distribution. Brief comment is also given on immature plumages, and the growing exploitation and pollution of coastal waters. 相似文献
6.
E. Fischer H.J.T. Venter D. Killmann U. Meve A.M. Venter 《South African Journal of Botany》2011,77(3):680-684
A new species, Epistemma neuerburgii is described. This species was discovered in the Nyungwe National Park, Rwanda, Tropical Africa during a field investigation of epiphytes in montane rainforest. It was, however, also found in Uganda, in similar environment. E. neuerburgii is the fourth species described for Epistemma, but the other three species are found about 2000 km to the west in Cameroon, Gabon, Ghana, Ivory Coast and Nigeria. E. neuerburgii is an epiphytic climber distinguished by fairly large lanceolate leaves and conspicuous reddish-purple flowers with corolline white, densely hairy corona lobes. 相似文献
7.
Mutschmann F 《Diseases of aquatic organisms》2004,60(3):215-222
A proliferous, polycystic and sometimes fatal kidney disease due to an infection with myxosporidia is reported in 24 of 28 hyperoliid frogs (Afrixalus dorsalis, Hyperolius concolor, Hyperolius sp.) from Nigeria, Ghana and Tanzania. In line with pathological changes in fish, the disease is described as 'frog kidney enlargement disease' (FKED). Myxosporidian plasmodia, different developmental stages and spores occurred in the kidney, ureter, and urinary bladder and in the intestine of the frogs. The parasite belongs to the genus Hoferellus and is presented as a new species: H. anurae n. sp. Spores are similar in size and structure to other Hoferellus species in fish but differ by the presence of a more prominent suture line and shorter caudal appendages. This is the first report on a Hoferellus species in amphibians as well as the first report of the genus Hoferellus in African vertebrates. 相似文献
8.
中国细长蚁属系统分类研究(膜翅目,蚁科) 总被引:1,自引:0,他引:1
在中国记载细长蚁属Tetraponera F. Smith昆虫13种,其中在云南省描述5新种,报道中国1新纪录种.编制了工蚁的分种检索表.评论了该属中国种类的分类历史.13个已知种依次是红黑细长蚁T.rufonigra(Jerdon),凹唇细长蚁T.concava sp.nov.,宾氏细长蚁T.binghami(Forel),狭唇细长蚁T.attenuata F.Smith,显赫细长蚁T.notabilis Ward,光亮细长蚁T.nitida(F.Smith),隆背细长蚁T.convexa sp.nov.,榕细长蚁T.microcarpa Wu et Wang,叉唇细长蚁T.furcata sp.nov.,尖唇细长蚁T.protensa sp.nov.,飘细长蚁T.allaborans(Walker),无缘细长蚁T.amargina sp.nov,平静细长蚁T.modesta(F.Smith).显赫细长蚁T.notabilis Ward为中国新纪录种. 相似文献
9.
Mpho Maepa Michael Oluwatosin Bodunrin Nicholas W. Burman Joel Croft Shaun Engelbrecht A. O. Ladenika O. S. MacGregor Kevin G. Harding 《The International Journal of Life Cycle Assessment》2017,22(7):1159-1164
Purpose
Life cycle assessments (LCAs) are considered common quantitative environmental techniques to analyze the environmental impact of products and/or services throughout their entire life cycle. A few LCA studies have been conducted in West Africa. This study aimed to discuss the availability of LCA (and similar) studies in Nigeria, Ghana, and Ivory Coast.Methods
An online literature review of reports published between 2000 and 2016 was conducted using the following keywords: “life cycle assessment,” “carbon footprinting,” “water footprinting,” “environmental impact,” “Nigeria,” “Ghana” and “Ivory Coast.”Results and discussion
A total of 31 LCA and environmental studies in Nigeria, Ghana, and Ivory Coast were found; all but one were conducted after 2008. These were mainly academic and most were publicly available. The industries studied included energy sector, waste management, real estate, food sector, and others such as timber and gold. The minimal number of studies on LCAs and environmental impacts in these West African states could be because companies are failing to promote quantitative environmental studies or studies are kept internally for the use of other assessment techniques. Furthermore, it could be that academic research institutions lack cutting-edge research resources for LCA, environmental impact, carbon, and water footprinting studies.Conclusions
Further quantitative environmental studies should be conducted in Nigeria, Ghana, and Ivory Coast to increase the understanding of environmental impacts. In these countries, the existence of LCA studies (and by association the localized life cycle inventory (LCI) datasets) is crucial as more companies request this information to feed into background processes.10.
The distribution, identification, and naming of the Mastomys natalensis species complex in southern Africa (Rodentia: Muridae) 总被引:2,自引:0,他引:2
Christopher A. Green Hillary Keogh‡ D. H. Gordon M. Pinto E. K. Hartwig ‡‡ 《Journal of Zoology》1980,192(1):17-23
Three hundred and forty seven rats belonging to the Mastomys natalensis complex (Smith, 1834) were live trapped from 60 localities in southern Africa. They were identified as species A, or B using either or both diploid chromosome number and haemoglobin electromorphs. These, and previously published data are presented to give a distribution of the species in southern Africa. It is suggested that workers may safely use the haemoglobin marker for identification purposes in this region as opposed to the more difficult chromosome marker. We suggest that species A can be referred to M. natalensis (Smith, 1834), and species B to M. coucha (Smith, 1836). We consider the two other oldest synonyms, M. caffer (Smith, 1834), and M. marikquensis (Smith, 1836). 相似文献
11.
B.G.OGUNJEMITE B.A.JAYI E.A.AGBELUSI 《动物学报》2007,53(4):579-588
研究了尼日利亚三处黑猩猩群落的生境结构,并利用点中心四分样方法评估了植被。共记录了38科150种植物,其中位于尼日利亚东北部的Gashaka Gumti国立公园Kwano栖息地(A区)有28科70种、位于尼日利亚东南部的Cross Rivers国立公园Butatong区域(B区)有36科120种、位于尼日利亚西南部的Ise森林保护区(C区)有30科92种。23科(60.53%)34种植物(22.67%)为三个区域的共有种,包括Afzelia africana、Drypetesgilgiana、Blighia sapida、Brachystegia eurycoma、Tetrapleuratetraptera等。在所有区域,对黑猩猩重要的科包括夹竹桃科(羊角棉Alstonia boonei、Picralima nitida)、含羞草亚科(腺瘤豆Piptadeniastrumafricanum、Tetrapleuratetraptera)、云实亚科(Brachystegiaspp.、Daniellia ogea)、桑科(非洲毒箭木Antiaris africana、Bosqueia angolensis、Ficusspp.)和梧桐科(Colaspp.、Sterculiaspp.)。在所有区域中,1m-10m高的树木是最常见的,胸径分布为B区最高,次之为C区,A区最低。结果表明,在尼日利亚的黑猩猩生境中具有重要的关键性植物,植物的垂直分层结构是尼日利亚黑猩猩生境管理的重要方面。 相似文献
12.
Kristan M Fleischmann H della Torre A Stich A Curtis CF 《Medical and veterinary entomology》2003,17(3):326-332
Resistance to pyrethroid insecticides and DDT caused by the kdr gene in the malaria vector Anopheles gambiae Giles s.s. (Diptera: Culicidae) has been reported in several West African countries. To test for pyrethroid resistance in two more countries, we sampled populations of the An. gambiae complex from south-western Ghana and from urban and rural localities in Ogun State, south-west Nigeria. Adult mosquitoes, reared from field-collected larvae, were exposed to the WHO-recommended discriminating dosage of exposure for 1 h to DDT 4%, deltamethrin 0.05% or permethrin 0.75% and mortality was recorded 24 h post-exposure. Susceptibility of An. gambiae s.l. to DDT was 94-100% in Ghana and 72-100% in Nigeria, indicating low levels of DDT resistance. Deltamethrin gave the highest mortality rates: 97-100% in Ghana, 95-100% in Nigeria. Ghanaian samples of An. gambiae s.l. were fully susceptible to permethrin, whereas some resistance to permethrin was detected at 4/5 Nigerian localities (percentage mortalities 75, 82, 88, 90 and 100%), with survivors including both An. arabiensis Patton and An. gambiae s.s. identified by PCR assay. Even so, the mean knockdown time was not significantly different from a susceptible reference strain, indicating absence or low frequency of kdr-type resistance. Such low levels of pyrethroid resistance are unlikely to impair the effectiveness of pyrethroid-impregnated bednets against malaria transmission. Among Nigerian samples of An. gambiae s.l., the majority from two urban localities were identified as An. arabiensis, whereas the majority from rural localities were An. gambiae s.s. These findings are consistent with those of M. Coluzzi et al. (1979). Differences of ecological distribution between molecular forms of An. gambiae s.s. were also found, with rural samples almost exclusively of the S-form, whereas the M-form predominated in urban samples. It is suggested that 'urban island' populations of An. arabiensis and of An. gambiae s.s. M-form in the rainforest belt of West Africa might be appropriate targets for elimination of these malaria vectors by the sterile insect technique. 相似文献
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The incidence of twin births in Accra and Kumasi, the two major cities in Ghana, was investigated. In Accra, data were collected from the Korle-Bu Teaching Hospital while data were collected and analyzed from the Komfo Anokye Teaching Hospital in Kumasi. Both hospitals are the leading teaching hospitals in Ghana. The data consisted mainly of single and twin births recorded in the hospitals over a period of 12 years in Accra (1988-1999) and 15 years in Kumasi (1985-1999). The study revealed an incidence of 33.4 twin births per thousand live births for Accra and 26.6 twin births per thousand live births for Kumasi. Though these values are not as high as those reported among the Yoruba tribe of southwest Nigeria, who are reported to have the highest twin birth rates in the world, the present values still rank among the highest recorded twin birth rates. 相似文献
15.
We investigated the major patterns of plant rarity in sub-Saharan Africa, and looked for the most significant gaps in the reserve network of the region in terms of representing the distribution of threatened and geographically rare plants. Comparisons of the species ranges captured by the network of reserves were made against the proportion of species captured by randomly generated sets of areas and against a theoretical near minimum set of areas that represent all species once. At this scale of analysis, the network of large IUCN-coded reserves (the official ‘protected areas’) performs poorly against random and systematic selection procedures. Significant gaps in the IUCN-coded protected areas are in coastal Gabon/Cameroon, in the various tropical montane forest areas (Cameroon Highlands, Eastern Arc Mountains, Ethiopian Mountains), in lowland coastal eastern Africa, and in the South African Cape. Some of these gaps, for example in the Eastern Arc and eastern African coastal regions, are covered on the ground by a network of Forest Reserves under the management of national Forestry Authorities. The networks of Forest Reserves in Ghana, Nigeria, Cameroon, Uganda, Kenya, Zimbabwe, Zambia and Sierra Leone also fill reservation gaps for rare African plants in these countries. Upgrading the conservation status of some key Forest Reserves, which has been gradually happening for some decades, is proposed as an efficient way to enhance the protected area network of the Afrotropical region for the conservation of rare African plant species. 相似文献
16.
The genus Platyscelio Kieffer (Hymenoptera: Platygastridae, Scelioninae) is a widespread group in the Old World, found from West Africa to northern Queensland, Australia. The species concepts are revised and a key to world species is presented. The genus is comprised of 6 species, including 2 known species which are redescribed: Platyscelioafricanus Risbec (Benin, Cameroon, Central African Republic, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Kenya, Mozambique, Nigeria, Sierra Leone, South Africa, Tanzania, Togo, Uganda, Yemen, Zimbabwe); and Platysceliopulchricornis Kieffer (Australia, Bangladesh, China, India, Indonesia, Japan, Malaysia, Papua New Guinea, Philippines, Solomon Islands, Taiwan, Thailand, Vanuatu, Vietnam). Five species-group names are considered to be junior synonyms of Platysceliopulchricornis: Platyscelioabnormis Crawford syn. n., Platysceliodunensis Mukerjee syn. n., Platysceliomirabilis Dodd syn. n., Platysceliopunctatus Kieffer syn. n., and Platysceliowilcoxi Fullaway. The following species are hypothesized and described as new taxa: Platyscelioarcuatus Taekul & Johnson, sp. n. (Western Australia); Platysceliomysterium Taekul & Johnson, sp. n. (Zimbabwe, Botswana, South Africa); Platysceliomzantsi Taekul & Johnson, sp. n. (South Africa); and Platysceliostriga Taekul & Johnson, sp. n. (Western Australia). 相似文献
17.
Jaja BN Olabiyi O Noronha CC 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2010,68(2):175-183
The dermal ridges on the surfaces of the palms and the fingers form dermatoglyphic patterns which are phylogenetically stable traits useful for evaluating interpopulation affinities and distinctiveness. In this study, these traits were investigated according to traditional methods among the Ogoni people of the Niger Delta region of Southern Nigeria, considering the uncertainties surrounding the people's historiography and the paucity of morphologic studies on the tribe. The evidences of finger whorl pattern frequencies, Total Ridge Count and palmar A-B ridge count indicate the close dermatoglyphic resemblance of the Ogoni to tribal populations of southern Ghana. These findings have implications as to the likely provenance of the Ogoni people, providing support to the traditionally view among the people that their ancestors are migrants from some tribe in southern Ghana, West Africa. 相似文献
18.
A total of 298 fish specimens belonging to seven families were caught during ichthyoplanktonic survey of three rivers within the Ewekoro cement facility catchment area located in southwestern Nigeria. The highest numbers of specimens were caught from Alaguntan (37.0%) and Elebute (36.6%) rivers while 28.9% of the fish samples were collected from Itori River. The fish population and species diversity recorded in the catchment rivers were significantly lower (p < 0.05) than comparative catches from Ewekoro River located about 30 km downstream of the factory operational area. The food items ingested by the specimens across the seasons in the catchment rivers revealed obvious differences in diet with some degree of overlap in the fish trophic preferences. However, the omnivorous species dominated the catches in each of the rivers, irrespective of season. Categorization of the fish specimens based on habitat-related adaptive physiology showed that a significant number of the fish from Alaguntan and Itori Rivers have accessory respiratory organs. The four species with accessory respiratory organs were Polypterus senegalus Curv., Clarias gariepinus C. & V., Ctenopoma kingslayae Gun. and Channa obscura Smith. Of the 12 fish species recorded in the Ewekoro cement facility catchment rivers, only P. senegalus, C. gariepinus, C. obscura and Oreochromis niloticus (Trew.) are valuable food fishes in southwestern Nigeria. 相似文献
19.
中国云南臭蚁属二新种记述 (膜翅目:蚁科) 总被引:2,自引:0,他引:2
描述了中国云南省南部热带雨林臭蚁属Dolichoderus Lund 2新种.目前为止已在中国记载该属昆虫10种:西伯利亚臭蚁D.sibiricus Emery、鞍背臭蚁D.sagmanotus Xu,sp.nov.、费氏臭蚁D.feae Emery、黑腹臭蚁D.taprobanae(Smith)、平背臭蚁D.flatidorsus Zhou、毛臭蚁D.pilosus Zhou、邻臭蚁D.affinis Emery、凹头臭蚁D.incisus Xu、黑可可臭蚁D.thoracicus(Smith)、鳞结臭蚁D.squamanodus Xu,sp.nov..提供了10个中国已知种的工蚁分种检索表. 相似文献
20.
Kurt Jordaens Georg Goergen Massimiliano Virgilio Thierry Backeljau Audrey Vokaer Marc De Meyer 《PloS one》2015,10(10)
The identification of Afrotropical hoverflies is very difficult because of limited recent taxonomic revisions and the lack of comprehensive identification keys. In order to assist in their identification, and to improve the taxonomy of this group, we constructed a reference dataset of 513 COI barcodes of 90 of the more common nominal species from Ghana, Togo, Benin and Nigeria (W Africa) and added ten publically available COI barcodes from nine nominal Afrotropical species to this (total: 523 COI barcodes; 98 nominal species; 26 genera). The identification accuracy of this dataset was evaluated with three methods (K2P distance-based, Neighbor-Joining (NJ) / Maximum Likelihood (ML) analysis, and using SpeciesIdentifier). Results of the three methods were highly congruent and showed a high identification success. Nine species pairs showed a low (< 0.03) mean interspecific K2P distance that resulted in several incorrect identifications. A high (> 0.03) maximum intraspecific K2P distance was observed in eight species and barcodes of these species not always formed single clusters in the NJ / ML analayses which may indicate the occurrence of cryptic species. Optimal K2P thresholds to differentiate intra- from interspecific K2P divergence were highly different among the three subfamilies (Eristalinae: 0.037, Syrphinae: 0.06, Microdontinae: 0.007–0.02), and among the different general suggesting that optimal thresholds are better defined at the genus level. In addition to providing an alternative identification tool, our study indicates that DNA barcoding improves the taxonomy of Afrotropical hoverflies by selecting (groups of) taxa that deserve further taxonomic study, and by attributing the unknown sex to species for which only one of the sexes is known. 相似文献