scholarly journals The vegetation of recently fallowed Masakwa fields in the Chad basin

2011 ◽  
Vol 14 ◽  
pp. 24-28
Author(s):  
Mandingo Ataholo ◽  
Rüdiger Wittig
Keyword(s):  
West Africa ◽  
Sorghum Bicolor ◽  
Sensu Stricto ◽  
The Other ◽  
First Year ◽  
Lake Chad ◽  
Pioneer Vegetation ◽  
Hibiscus Trionum ◽  
Celosia Argentea ◽  
Sahelian Zone

On the clay plains surrounding Lake Chad (West Africa: northern Sudanian and southern Sahelian zone), certain varieties of pearl millet (Sorghum bicolor), commonly referred to as Masakwa, are cultivated during the dry season. Recently fallowed Masakwa fields support a particular progression of pioneer vegetation. In the first year of fallow, the pioneer vegetation typically belongs to the class Echinochloetea colonae Wittig 2005 and can be classified as Hygrophiletum auriculatae sensu lato. Approximately half of the stands consist of the Hygrophiletum auriculatae Ataholo 2002 sensu stricto, whereas the other half is primarily composed of a Celosia argentea-Hibiscus trionum community. After two years of fallow, the vegetation is typically formed by the Sorghetum arundinacei Ataholo 2002, which, in a few cases, can also occur in the first fallow year.

The cytotaxonomy of Simulium sanctipauli sensu stricto (Diptera: Simuliidae) in Ghana and the Côte d’Ivoire

1999 ◽  
Vol 89 (1) ◽  
pp. 25-33 ◽  
Author(s):  
D.A. Boakye ◽  
G.K. Fiasorgbor ◽  
B.K. Bougsere ◽  
S. Naniogue
Keyword(s):  
West Africa ◽  
Cote D'ivoire ◽  
Côte D’Ivoire ◽  
Sensu Stricto ◽  
Control Programme ◽  
The Other ◽  
Cote D’Ivoire ◽  
Côte D'ivoire ◽  
The Status ◽  
Onchocerciasis Control

AbstractThe status of the different cytological variants of Simuliumsanctipaulisensu stricto Vajime & Dunbar (sensu b8Post, 1986) found in Ghana and Côte d’Ivoire is cytotaxonomically evaluated in view of recent revisions of the S. sanctipauli subcomplex. Three geographical variants designated as ‘Pra’, ‘Comoé’ and ‘Sassandra’forms of S. sanctipauli are described. The ‘Pra’ form is genetically differentiated from the other two forms by a distinct sex-determining system. The ‘Comoé’ and ‘Sassandra’ forms are considered as the two ends of an interspecific stepped cline with the River Bandama basin as the zone of contact. The possibility that the ‘Comoé’ form populations breeding in southwestern Ghana could serve as reinvading S. sanctipauliinto the Onchocerciasis Control Programme (OCP) area in West Africa is discussed.

Suitability of forms of preparing seeds of Dalbergia miscolobium Benth for exposure to the tetrazolium test / Adequação das formas de preparação de sementes de Dalbergia miscolobium Benth para exposição ao teste de tetrazolium

2017 ◽  
Vol 1 (1) ◽  
Author(s):  
Juliana Martins de Mesquita Matos ◽  
Rosana De Carvalho Cristo Martins ◽  
Valéria Regina Bellotto ◽  
Lilian Gomes da Silva Rocha ◽  
Eloiza Aparecida Barbosa ◽  
...  
Keyword(s):  
Endangered Species ◽  
Filter Paper ◽  
Federal District ◽  
Complete Removal ◽  
Sensu Stricto ◽  
The Other ◽  
Distrito Federal ◽  
Viable Seeds ◽  
Range Test ◽  
Tetrazolium Test

Dalbergia miscolobium or Jacarandá do Cerrado is a species of legume in the Fabaceae family. It occurs in the sensu stricto Cerrado and in the dystrophic cerradão. It shows potential for landscaping and for recovering damaged areas. It is an endangered species and therefore is protected by the law that prevents cut in areas of the Federal District (Decree No. 14.783/93). The purpose of this study was to determine the best procedure to prepare seeds of Dalbergia miscolobium to assess viability in the tetrazolium test. We carried out the following treatments: i) hydration on filter paper at 25 ° C, ii) hydration on filter paper at 25 ° C followed by a cut in the tegument and iii) hydration on filter paper at 25 ° C followed bya complete removal of the tegument. The results were analyzed using analysis of variance and the Tukey range test. The analyzes showed that the best procedure to prepare seeds of Dalbergia miscolobium is the treatment in which there is a hydration followed by the complete removal of the integument. Where 78% of the seeds showed uniform staining, indicating that the seeds analyzed are of good quality. The other treatments, hydration and hydration followed by cutting, showed respectively 35% and 41% of viable seeds. RESUMO A Dalbergia miscolobium ou Jacarandá do Cerrado é uma espécie de leguminosa da família Fabaceae. Ocorre no sentido stricto Cerrado e no cerradão distrófico. Possui potencial para paisagismo e para recuperar áreas degradadas. É uma espécie ameaçada de extinção e, portanto, está protegida pela lei que previne o corte em áreas do Distrito Federal (Decreto 14.783 / 93). O objetivo deste estudo foi determinar o melhor procedimento de prepararação das sementes de Dalbergia miscolobium para serem submetidas à análise de viabilidade pelo teste de tetrazólio. Foram realizados os seguintes tratamentos: i) hidratação em papel de filtro a 25 ° C, ii) hidratação em papel de filtro a 25 ° C seguida de um corte no tegumento e iii) hidratação em papel de filtro a 25 ° C seguido de remoção completa do tegumento. Os resultados foram analisados utilizando-se a análise de variância e o teste de médias de Tukey. As análises mostraram que o melhor procedimento para preparar sementes de Dalbergia miscolobium é o tratamento em que há uma hidratação seguida pela remoção completa do tegumento, onde 78% das sementes apresentaram coloração uniforme, indicando que as sementes analisadas são de boa qualidade. Os demais tratamentos, hidratação e hidratação seguida de corte, mostraram respectivamente 35% e 41% de sementes viáveis.

scholarly journals Laboratory and microcosm experiments reveal contrasted adaptive responses to ammonia and water mineralisation in aquatic stages of the sibling species Anopheles gambiae (sensu stricto) and Anopheles coluzzii

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Nwamaka Oluchukwu Akpodiete ◽  
Frédéric Tripet
Keyword(s):  
West Africa ◽  
Anopheles Gambiae ◽  
Emerging Adults ◽  
Sibling Species ◽  
Adult Emergence ◽  
Ecological Speciation ◽  
Sensu Stricto ◽  
Rice Fields ◽  
Anopheles Coluzzii ◽  
Phenotypic Quality

Abstract Background The sibling species of the malaria mosquito, Anopheles gambiae (sensu stricto) and Anopheles coluzzii co-exist in many parts of West Africa and are thought to have recently diverged through a process of ecological speciation with gene flow. Divergent larval ecological adaptations, resulting in Genotype-by-Environment (G × E) interactions, have been proposed as important drivers of speciation in these species. In West Africa, An. coluzzii tends to be associated with permanent man-made larval habitats such as irrigated rice fields, which are typically more eutrophic and mineral and ammonia-rich than the temporary rain pools exploited by An. gambiae (s.s.) Methods To highlight G × E interactions at the larval stage and their possible role in ecological speciation of these species, we first investigated the effect of exposure to ammonium hydroxide and water mineralisation on larval developmental success. Mosquito larvae were exposed to two water sources and increasing ammonia concentrations in small containers until adult emergence. In a second experiment, larval developmental success was compared across two contrasted microcosms to highlight G × E interactions under conditions such as those found in the natural environment. Results The first experiment revealed significant G × E interactions in developmental success and phenotypic quality for both species in response to increasing ammonia concentrations and water mineralisation. The An. coluzzii strain outperformed the An. gambiae (s.s.) strain under limited conditions that were closer to more eutrophic habitats. The second experiment revealed divergent crisscrossing reaction norms in the developmental success of the sibling species in the two contrasted larval environments. As expected, An. coluzzii had higher emergence rates in the rice paddy environment with emerging adults of superior phenotypic quality compared to An. gambiae (s.s.), and vice versa, in the rain puddle environment. Conclusions Evidence for such G × E interactions lends support to the hypothesis that divergent larval adaptations to the environmental conditions found in man-made habitats such as rice fields in An. coluzzii may have been an important driver of its ecological speciation.

scholarly journals COVID-19 in West Africa: regional resource mobilisation and allocation in the first year of the pandemic

2021 ◽  
Vol 6 (5) ◽  
pp. e004762
Author(s):  
Césaire Ahanhanzo ◽  
Ermel Ameswue Kpogbe Johnson ◽  
Ejemai Amaize Eboreime ◽  
Sombié Issiaka ◽  
Ben Idrissa Traoré ◽  
...  
Keyword(s):  
West Africa ◽  
Ebola Virus ◽  
Virus Disease ◽  
First Year ◽  
African Countries ◽  
Response Strategies ◽  
African Health ◽  
The Usa ◽  
Health Organization ◽  
Resource Mobilisation

The world continues to battle the ongoing COVID-19 pandemic. Whereas many countries are currently experiencing the second wave of the outbreak; Africa, despite being the last continent to be affected by the virus, has not experienced as much devastation as other continents. For example, West Africa, with a population of 367 million people, had confirmed 412 178 cases of COVID-19 with 5363 deaths as of 14 March 2021; compared with the USA which had recorded almost 30 million cases and 530 000 deaths, despite having a slightly smaller population (328 million). Several postulations have been made in an attempt to explain this phenomenon. One hypothesis is that African countries have leveraged on experiences from past epidemics to build resilience and response strategies which may be contributing to protecting the continent’s health systems from being overwhelmed. This practice paper from the West African Health Organization presents experience and data from the field on how countries in the region mobilised support to address the pandemic in the first year, leveraging on systems, infrastructure, capacities developed and experiences from the 2014 Ebola virus disease outbreak.

scholarly journals Eurasian and North American phylogeny of Turolian hipparionine horses (Perissodactyla, Mammalia) in China

1992 ◽  
Vol 6 ◽  
pp. 305-305
Author(s):  
Mahito Watabe
Keyword(s):  
North America ◽  
North American ◽  
Northern China ◽  
Sensu Stricto ◽  
The Other ◽  
Dental Morphology ◽  
Facial Morphology ◽  
Open Land ◽  
Specialized Form ◽  
Eastern Half

The late Miocene Chinese hipparions are morphologically diversified showing similarity to both western Old World's and North American forms. Two Chinese taxa that are phylogenetically related to western Old World's forms are Hipparion fossatum (= H. forstende) from Baode (Shanxi) and H. hippidiodus from Qingyang (Gansu) and Baode. The former is related to H. mediterraneum and the latter to H. urmiense - platygenys from the Turolian localities in the western Old World. H. fossatum and H. hippidiodus are associated with the “dorcadoides” (open-land) and “mixed” faunas in northern China. Hipparion fossatum that is characterized by POF located close to the orbit co-occurs with large and morphologically specialized form, H. dermatorhinum in Baode (Loc.30). H. hippidiodus with reduced POF is discovered with smaller H. coelophyes in Loc. 43, 44 (Baode) and Loc. 115 (Gansu).The hipparions associated with the “gaudryi” (forest) fauna are characterized by well defined and small POF located far from the orbit. Those forms are: H. platyodus from Loc. 70; H. ptychodus from Loc. 73; H. tylodus from Hsi-Liang in Yushe - Wuxiang basins; and H. sefvei from Loc. 12 at Xin-an in Henan province. H. coelophyes from Baode (Loc.43 & 44) and Qingyang (Loc. 115) also show similar facial morphology to the these forms, although it has small size and shallow POF. Those forms are similar in facial and dental morphology to Hipparion sensu stricto and some species of Cormohipparion in North America.The assemblages of Chinese hipparions are composed of two groups whose members are phylogenetically similar to the forms from both western part of Eurasia and North America. The “gaudryi” fauna is considered younger than the other two on the basis of faunal analyses. The similarity in hipparionine taxonomy between northern China and North America in the latest Miocene is an evidences for possible faunal interchange(s) occurred during that period, as suggested by taxonomic analyses on carnivores and proboscideans in eastern half of Eurasia and North America.

A REVISION OF THE SYSTEMATICS OF ACALYMMA SENSU STRICTO BARBER (COLEOPTERA: CHRYSOMELIDAE) FROM NORTH AMERICA INCLUDING MEXICO

1980 ◽  
Vol 112 (S112) ◽  
pp. 1-92 ◽  
Author(s):  
D.D. Munroe ◽  
Ray F. Smith
Keyword(s):  
New Species ◽  
North America ◽  
Male Genitalia ◽  
Sensu Stricto ◽  
The Other ◽  
New Subspecies ◽  
Distribution Maps ◽  
Species Groups

AbstractThe systematics of Acalymma sensu stricto of North America including Mexico are revised. Acalymma sensu stricto is defined and distinguished from the other species groups of Acalymma. Sixteen species are discussed including four new species: A. blomorum, A. palomarense, A. invenustum, and A. luridifrons all from Mexico. Three new subspecies of A. blandulum (LeConte) are described: blandulum (LeConte) new status, nigriventre, and yucatanense. Acalymma coruscum costaricense Bechyné is placed as a synonym of A. innubum (Fabricius). Keys are presented to all species and subspecies. Habitus and male genitalia drawings are given for all species and distribution maps are given where appropriate.

scholarly journals Spatially different annual cycles but similar haemosporidian infections in distant populations of collared sand martins

BMC Zoology ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Steffen Hahn ◽  
Martins Briedis ◽  
Christos Barboutis ◽  
Raffaella Schmid ◽  
Martin Schulze ◽  
...  
Keyword(s):  
West Africa ◽  
Chronic Infection ◽  
Blood Parasite ◽  
Spring Migration ◽  
Lake Chad ◽  
Annual Cycles ◽  
Nonbreeding Season ◽  
Breeding Populations ◽  
High Parasitaemia ◽  
Western Palaearctic

Abstract Background Populations of long-distance migratory birds experience different environments and are consequently exposed to different parasites throughout their annual cycles. Though, specific whereabouts and accompanied host-parasite interactions remain unknown for most migratory passerines. Collared sand martins (Riparia riparia) breeding in the western Palaearctic spend the nonbreeding period in Africa, but it is not yet clear whether specific populations differ in overwintering locations and whether these also result in varying infections with vector-transmitted endoparasites. Results Geolocator tracking revealed that collared sand martins from northern-central and central-eastern Europe migrate to distant nonbreeding sites in West Africa and the Lake Chad basin in central Africa, respectively. While the ranges of these populations were clearly separated throughout the year, they consistently spent up to 60% of the annual cycle in Africa. Ambient light recorded by geolocators further indicated unsheltered roosting during the nonbreeding season in Africa compared to the breeding season in Europe. We found 5–26% prevalence of haemosporidian parasites in three breeding populations and one migratory passage population that was only sampled but not tracked. In total, we identified seven Plasmodium and nine Haemoproteus lineages (incl. two and seven new lineages, respectively), the latter presumably typical for swallows (Hirundinae) hosts. 99.5% of infections had a low intensity, typical for chronic infection stages, whereas three individuals (0.5%) showed high parasitaemia typical for acute infections during spring migration and breeding. Conclusions Our study shows that blood parasite infections are common in several western Palaearctic breeding populations of collared sand martins who spent the nonbreeding season in West Africa and the lake Chad region. Due to long residency at the nonbreeding grounds blood parasite transmissions may mainly occur at host population-specific residences sites in Europe and Africa; the latter being likely facilitated by unsheltered roosting and thus high vulnerability to hematophagous insects. The rare cases of high parasitaemia during spring migration and breeding further indicates either relapses of chronic infection or primary infections which occurred shortly before migration and during breeding.

Saotomia tuberculata, a new genus and species of Peritelini (Coleoptera; Curculionidae; Entiminae) from São Tomé, West Africa

Zootaxa ◽  
2021 ◽  
Vol 4966 (5) ◽  
pp. 571-577
Author(s):  
ROMAN BOROVEC ◽  
ROBERT ANDERSON
Keyword(s):  
West Africa ◽  
New Genus ◽  
The Other ◽  
New Genus And Species

Saotomia tuberculata, a new genus and species of Peritelini (Curculionidae; Entiminae) from São Tomé, West Africa is described. The new genus is most similar to the other African genera Dysommatus Marshal, 1933 and Fernandius Marshall, 1954. Important taxonomic characters are illustrated. 

Rediagnosis of the squat lobster genus Gastroptychus Caullery, 1896, with a new genus Sternostylus and a new family Sternostylidae (Crustacea: Decapoda: Anomura: Chirostyloidea)

Zootaxa ◽  
2018 ◽  
Vol 4524 (1) ◽  
pp. 77 ◽  
Author(s):  
KEIJI BABA ◽  
SHANE T. AHYONG ◽  
KAREEN E. SCHNABEL
Keyword(s):  
Type Species ◽  
Anterior Margin ◽  
New Genus ◽  
Sister Group ◽  
Sensu Stricto ◽  
The Other ◽  
Squat Lobster ◽  
Terminal Spine ◽  
New Family ◽  
Left And Right

The chirostyloidean squat lobster genus Gastroptychus Caullery, 1896 is revised and is split into two genera: Gastroptychus sensu stricto (type species, Ptychogaster spinifer A. Milne-Edwards, 1880) and Sternostylus new genus (type species, Ptychogaster formosus Filhol, 1884). Gastroptychus sensu stricto, is restricted to nine species with a sternal plastron, at sternite 3, abruptly demarcated from the preceding sternites (excavated sternum) by a distinct step forming a well-defined transverse or concave anterior margin at the articulation with maxillipeds 3, the maxillipeds 3 widely separated, with the distal parts accommodated in the excavated sternum between the left and right maxillipeds 3 when folded, and the P2–4 dactyli with the terminal spine demarcated by a suture. Sternostylus new genus, represented by 12 species, has the sternite 3 anteriorly bluntly produced medially and steeply sloping anterodorsally to the anterior sternite, with a pair of spines directly behind the anterior margin, the left and right maxillipeds 3 adjacent, and the P2–4 dactyli ending in an indistinctly demarcated corneous spine. The above-mentioned characters of Gastroptychus are consistent with Chirostylidae sensu stricto. Published molecular phylogenies indicate, however, that Sternostylus is the sister group to all the other Chirostylidae, and is designated the type genus of a new family, Sternostylidae. 

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