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1.
PLoS Negl Trop Dis ; 15(2): e0009062, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33524028

RESUMO

Phlebotomine sand flies transmit many viral protozoan and bacterial pathogens of public health importance. Knowledge of the ecologic factors influencing their distribution at local scale can provide insights into disease epidemiology and avenues for targeted control. Animal sheds, termite mounds and houses are important peri-domestic and domestic habitats utilized by different sand flies as resting or breeding habitats. However, our knowledge for selection of these habitats by sand flies remains poor. Here, we tested the hypothesis that these habitat types harbor different composition of sand fly species and differ in their volatile chemistry that could influence sand fly selection. To achieve this, we employed CDC light traps following a cross-sectional survey to investigate the distribution of sand flies in the three habitats in an endemic site for leishmaniasis in Kenya. The study was carried out during the dry season, when sand flies are optimally abundant in 2018 and 2020. Sand fly abundance did not vary between the habitats, but species-specific differences in abundance was evident. Measures of sand fly community structure (Shannon diversity and richness) were highest in animal shed, followed by termite mound and lowest inside human dwelling (house). This finding indicates broader attraction of both sexes of sand flies and females of varying physiological states to animal sheds potentially used as breeding or resting sites, but also as a signal for host presence for a blood meal. Furthermore, gas chromatography-mass spectrometric analysis of volatiles collected from represented substrates associated with these habitats viz: human foot odor on worn socks (houses indoors), cow dung (animal sheds) and termite mounds (enclosed vent), revealed a total of 47 volatile organic compounds. Of these, 26, 35 and 16 were detected in human socks, cow dung and enclosed termite vent, respectively. Of these volatiles, 1-octen-3-ol, 6-methyl-5-hepten-2-one, α-pinene, benzyl alcohol, m-cresol, p-cresol and decanal, previously known as attractants for sandflies and other blood-feeding insects, were common to the habitats. Our results suggest that habitat volatiles may contribute to the composition of sand flies and highlight their potential for use in monitoring sand fly populations.

2.
PLoS Negl Trop Dis ; 15(2): e0009041, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33556068

RESUMO

The bioecology of phlebotomine sand flies is intimately linked to the utilization of environmental resources including plant feeding. However, plant feeding behavior of sand flies remains largely understudied for Afrotropical species. Here, using a combination of biochemical, molecular, and chemical approaches, we decipher specific plant-feeding associations in field-collected sand flies from a dry ecology endemic for leishmaniasis in Kenya. Cold-anthrone test indicative of recent plant feeding showed that fructose positivity rates were similar in both sand fly sexes and between those sampled indoors and outdoors. Analysis of derived sequences of the ribulose-1,5-bisphosphate carboxylase large subunit gene (rbcL) from fructose-positive specimens implicated mainly Acacia plants in the family Fabaceae (73%) as those readily foraged on by both sexes of Phlebotomus and Sergentomyia. Chemical analysis by high performance liquid chromatography detected fructose as the most common sugar in sand flies and leaves of selected plant species in the Fabaceae family. Analysis of similarities (ANOSIM) of the headspace volatile profiles of selected Fabaceae plants identified benzyl alcohol, (Z)-linalool oxide, (E)-ß-ocimene, p-cymene, p-cresol, and m-cresol, as discriminating compounds between the plant volatiles. These results indicate selective sand fly plant feeding and suggest that the discriminating volatile organic compounds could be exploited in attractive toxic sugar- and odor- bait technologies control strategies.

3.
Parasit Vectors ; 14(1): 4, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397448

RESUMO

BACKGROUND: In a recent study using DNA barcoding, we identified the plants fed upon by four Afro-tropical mosquito species that vector dengue, malaria, and Rift Valley fever. Herein, we have expanded on this study by investigating the role of three of the plants, Pithecellobium dulce (Fabaceae), Leonotis nepetifolia (Lamiaceae), and Opuntia ficus-indica (Cactaceae), on the survival, fecundity, and egg viability of the dengue vector Aedes aegypti. METHODS: We tested these effects using females that received (i) an initial three rations of blood meals and (ii) no blood meal at all. Two controls were included: age-matched females fed on glucose solution with or without an initial blood meal and those fed exclusively on blood meals. Data were collected daily over a 30-day period. The amino acid contents of Ae. aegypti guts and their respective diets were detected by coupled liquid chromatography-mass spectrometry. RESULTS: Females fed on P. dulce and an exclusively blood meal diet had a shorter survival than those fed on glucose. On the other hand, females fed on L. nepetifolia survived longer than those fed exclusively on blood meals, whereas those fed on O. ficus-indica had the shortest survival time. With an initial blood meal, females fed on L. nepetifolia laid 1.6-fold more eggs while those fed on the other diets laid fewer eggs compared to those fed exclusively on blood meals. Hatching rates of the eggs laid varied with the diet. Mass spectroscopic analysis of gut contents of mosquitoes exposed to the different diets showed qualitative and quantitative differences in their amino acid levels. CONCLUSION: Our findings highlight the central role of plant nutrients in the reproductive fitness of dengue vectors, which may impact their disease transmission potential.

4.
Zootaxa ; 4763(3): zootaxa.4763.3.4, 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33056855

RESUMO

It is proposed that the genus Stiptopodius Harold, 1871 should be subdivided into two species groups based on the shape of the lateral edge of the pronotum. Three new species are described from southern Africa: Stiptopodius peringueyi Daniel Deschodt, new species, Stiptopodius savuti Daniel Deschodt, new species, and Stiptopodius muellerae Daniel Deschodt, new species. Stiptopodius savuti new species is the first record of the genus from Botswana. A distribution map for the new taxa is provided. The identification key to the known species of Stiptopodius is updated.


Assuntos
Besouros , África Austral , Animais
5.
Zootaxa ; 4728(3): zootaxa.4728.3.4, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-32230563

RESUMO

Upsa centennial Deschodt, Sole Scholtz, new genus and species is described, celebrating a century of entomology at the University of Pretoria. This new genus in the dung beetle tribe Endroedyolini (Scarabaeidae: Scarabaeinae) occurs in the Albany Coastal Mistbelt forest in the Eastern Cape Province in South Africa. A distribution map and key for all genera and species in the tribe are provided.[Genus Zoobank url: urn:lsid:zoobank.org:act:92A64613-A8CE-48DF-84D9-7450EA1D40AA].


Assuntos
Besouros , Animais , Florestas , África do Sul
6.
Zootaxa ; 4635(1): zootaxa.4635.1.1, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31712492

RESUMO

The southern African genera Nemopterella Banks, 1910 and Nemia Navás, 1915 (Neuroptera: Nemopteridae: Nemopterinae) are revised. Nemopterella is split into three genera: Nemopterella sensu stricto with type species Nemopteryx africana Leach, 1815 (= Nemopterella africana), Afroptera gen. nov., with type species Nemopterella munroi Tjeder, 1967, and the monotypic genus Siccanda gen. nov., with type species Nemopterella arenaria Tjeder, 1967. Eight new species are described in Afroptera gen. nov.: A. acuta Abdalla Mansell sp. nov., A. alba Mansell Abdalla sp. nov., A. brinkmani Abdalla Mansell sp. nov., A. balli Abdalla Mansell sp. nov., A. cylindrata Abdalla Mansell sp. nov., A. folia Abdalla Mansell sp. nov., A. koranna Mansell Abdalla sp. nov., A. maraisi Abdalla Mansell sp. nov., as well as two new species in the genus Nemopterella: N. kabas Mansell Abdalla sp. nov., and N.cedrus Mansell Abdalla sp. nov.


Assuntos
Holometábolos , Distribuição Animal , Animais
7.
Zootaxa ; 4671(1): zootaxa.4671.1.11, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31716600

RESUMO

The recently described dung beetle tribe Byrrhidiini currently comprises seven genera and nineteen species (Davis et al. 2019). During a recent collecting expedition to the Brandberg Mountain [S21.11° E14.69°] in Namibia, a single male specimen, together with various disarticulated body parts of a new species belonging to this tribe were collected. It was found amongst dried hyrax (Procavia capensis) dung pellets between large granite boulders. This new species clearly fits the current definition of the genus Versicorpus Deschodt, Davis Scholtz, 2011. This raises the number of the constituent species of Versicorpus to three and that for Byrrhidiini to twenty.


Assuntos
Besouros , Animais , Expedições , Masculino , Namíbia
8.
Zootaxa ; 4648(1): zootaxa.4648.1.12, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31716968

RESUMO

Hyalonthophagus Palestrini Giacone, 1988, from Afrotropical savanna, is raised to generic status having been originally described as a subgenus within the genus Onthophagus Latreille, 1802. Hyalonthophagus pulcher Deschodt Davis, new species is described from the Northern Cape, South Africa. Maps are provided to show (1) the locally-restricted distribution pattern of the new species isolated from adjoining savanna in warm, dry Karoo climate to the south of the Orange River, and, (2) the disjunct distribution pattern in relation to those of three other southern African species centred in savanna to the northeast beyond areas with unsuitable climatic or ecological conditions. An assessment of the conservation status for Hyalonthophagus pulcher Deschodt Davis, new species is also provided.


Assuntos
Besouros , Animais , Clima , Ecologia , Rios , África do Sul
9.
Zootaxa ; 4544(4): 548-556, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30647257

RESUMO

Bostrichoclerus bicornus Van Dyke is known from southwest United States and northwest Mexico. To date, only two specimens have been captured: the holotype, collected on Isla Angel de la Guarda, in the Gulf of California, Mexico, and a second individual collected in San Bernardino County, California, United States. The original description of B. bicornus is brief and lacks any images. Considering its rarity, we present the redescription of this species based on the examination of the holotype and compare this taxon to similar genera of New World Tillinae. Images of the holotype and the Bostrichoclerus specimen collected in southern California are given. We conclude that B. bicornus is undoubtedly a member of the subfamily Tillinae with unclear intergeneric relations in the group.


Assuntos
Besouros , Animais , California , México , Sudoeste dos Estados Unidos
10.
Zootaxa ; 4504(1): 41-75, 2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30486035

RESUMO

The genus Macroderes Westwood, 1842 (Scarabaeidae: Scarabaeinae, tribe incertae sedis) is practically endemic to South Africa with only one species that is found little north in southern Namibia. The ranges of the species are limited to the winter-fall and bimodal biomes of South Africa comprising the regions of Richtersveld as extreme points of its northerly distribution, and extending to the south through Namaqualand to Cape Agulhas. The taxonomy of the genus is revised. Fourteen valid species are recognised and three others are of doubtful validity. Seven new species are described, these are: M. cederbergensis Abdalla Deschodt, new species, M. tortuosus Abdalla Scholtz, new species, M. gifboomi Abdalla Scholtz, new species, M. leipoldti Abdalla Deschodt, new species, M. oreatus Abdalla Deschodt, new species, M. porselinus Abdalla, new species, and M. soleiana Abdalla Deschodt, new species. Macroderes nitidus Harold, 1877 is redescribed and its lectotype is designated. The diagnostic characters as well as an updated geographic distribution of each species are summarised. An updated key of the genus, photographs of habitus, sclerites of internal sac, pronotum, pronotal punctures and elytra also are provided.


Assuntos
Besouros , Ecossistema , Distribuição Animal , Animais , Namíbia , Estações do Ano , África do Sul
11.
Zootaxa ; 4450(5): 501-549, 2018 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-30314251

RESUMO

The Mantispinae (Neuroptera: Mantispidae) genera of the Oriental and Palearctic regions are revised. A morphological key to the genera is generated. Austroclimaciella, Campancella, Mantispa, Mantispilla, Necyla, Stenomantispa and Tuberonotha are redescribed. The Ohl (2004) catalogue is updated for the relevant genera. Sagittalata (= Perlamantispa) is assigned as a synonym of Mantispilla which is restored as a valid genus. Orientispa is assigned as a synonym of Necyla.


Assuntos
Distribuição Animal , Insetos , Animais
13.
PLoS Negl Trop Dis ; 12(2): e0006185, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29462150

RESUMO

The global spread of vector-borne diseases remains a worrying public health threat, raising the need for development of new combat strategies for vector control. Knowledge of vector ecology can be exploited in this regard, including plant feeding; a critical resource that mosquitoes of both sexes rely on for survival and other metabolic processes. However, the identity of plant species mosquitoes feed on in nature remains largely unknown. By testing the hypothesis about selectivity in plant feeding, we employed a DNA-based approach targeting trnH-psbA and matK genes and identified host plants of field-collected Afro-tropical mosquito vectors of dengue, Rift Valley fever and malaria being among the most important mosquito-borne diseases in East Africa. These included three plant species for Aedes aegypti (dengue), two for both Aedes mcintoshi and Aedes ochraceus (Rift Valley fever) and five for Anopheles gambiae (malaria). Since plant feeding is mediated by olfactory cues, we further sought to identify specific odor signatures that may modulate host plant location. Using coupled gas chromatography (GC)-electroantennographic detection, GC/mass spectrometry and electroantennogram analyses, we identified a total of 21 antennally-active components variably detected by Ae. aegypti, Ae. mcintoshi and An. gambiae from their respective host plants. Whereas Ae. aegypti predominantly detected benzenoids, Ae. mcintoshi detected mainly aldehydes while An. gambiae detected sesquiterpenes and alkenes. Interestingly, the monoterpenes ß-myrcene and (E)-ß-ocimene were consistently detected by all the mosquito species and present in all the identified host plants, suggesting that they may serve as signature cues in plant location. This study highlights the utility of molecular approaches in identifying specific vector-plant associations, which can be exploited in maximizing control strategies such as such as attractive toxic sugar bait and odor-bait technology.


Assuntos
Comportamento Animal/fisiologia , Vetores de Doenças , Mosquitos Vetores/fisiologia , Odorantes , Extratos Vegetais/química , Plantas/química , Olfato , Monoterpenos Acíclicos , Aedes/fisiologia , Aldeídos , Alcenos , Animais , Anopheles/fisiologia , DNA de Plantas , Dengue/transmissão , Dengue/virologia , Vírus da Dengue , Comportamento Alimentar/psicologia , Feminino , Genes de Plantas/genética , Interações Hospedeiro-Parasita/fisiologia , Quênia , Malária/transmissão , Masculino , Monoterpenos , Plantas/classificação , Plantas/genética , Febre do Vale de Rift/transmissão , Sesquiterpenos
14.
Zootaxa ; 4362(2): 151-212, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29245424

RESUMO

 Afrotropical Psychopsidae Handlirsch are revised based on morphology. Molecular data from a previous study enables updated taxonomy in this revision, and morphology corroborates phylogenetic divergences. The genus Silveira was found to form a lineage separate from Zygophlebiinae based on molecular data and six morphological synapomorphies. In this revision, Silveira is moved to a new subfamily, leaving only Cabralis and Zygophlebius in Zygophlebiinae. Two new species of Cabralis are described. Afrotropical Psychopsidae now comprise ten species, three genera and two subfamilies. A dichotomous key to these taxa is provided, along with a web link to a fully-illustrated and interactive multi-access LUCID v3 key. High resolution images and distribution maps are provided for all species.


Assuntos
Holometábolos , Animais , Filogenia
15.
Zootaxa ; 4350(1): 106-120, 2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-29245568

RESUMO

Five new species of Cymatodera from Mexico, Guatemala, Honduras, Costa Rica and Panama are described here based on adult male and female specimens: Cymatodera humeralis sp. n; Cymatodera lorenae sp. n.; Cymatodera crassa sp. n.; Cymatodera depressa sp. n; and Cymatodera nigrofasciata sp. n. Male genitalia and other characters of taxonomic value are used for diagnostic purposes.


Assuntos
Besouros , Animais , América Central , Costa Rica , Feminino , Guatemala , Honduras , Masculino , México , Panamá
17.
PLoS One ; 11(8): e0161118, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27532606

RESUMO

Micro-organisms inhabiting animal guts benefit from a protected and nutrient-rich environment while assisting the host with digestion and nutrition. In this study we compare, for the first time, the bacterial and fungal gut communities of two species of the small desert dung beetle genus Pachysoma feeding on different diets: the detritivorous P. endroedyi and the dry-dung-feeding P. striatum. Whole-gut microbial communities from 5 individuals of each species were assessed using 454 pyrosequencing of the bacterial 16S rRNA gene and fungal ITS gene regions. The two bacterial communities were significantly different, with only 3.7% of operational taxonomic units shared, and displayed intra-specific variation. The number of bacterial phyla present within the guts of P. endroedyi and P. striatum individuals ranged from 6-11 and 4-7, respectively. Fungal phylotypes could only be detected within the gut of P. striatum. Although the role of host phylogeny in Pachysoma microbiome assembly remains unknown, evidence presented in this study suggests that host diet may be a deterministic factor.


Assuntos
Besouros/microbiologia , Microbioma Gastrointestinal , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Besouros/classificação , Besouros/genética , Dieta , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Microbioma Gastrointestinal/genética , Genes Bacterianos , Genes Fúngicos , Genes de Insetos , Proteínas de Insetos/genética , Filogenia , RNA Ribossômico 16S/genética , África do Sul , Especificidade da Espécie
18.
Sci Rep ; 6: 29168, 2016 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-27406468

RESUMO

Small mammals provide ecosystem services, acting, for example, as pollinators and seed dispersers. In addition, they are also disease reservoirs that can be detrimental to human health and they can also act as crop pests. Knowledge of their dispersal preferences is therefore useful for population management and landscape planning. Genetic data were used alongside landscape data to examine the influence of the landscape on the demographic connectedness of the Natal multimammate mouse (Mastomys natalensis) and to identify landscape characteristics that influence the genetic structure of this species across a spatially and temporally varying environment. The most significant landscape features shaping gene flow were aspect, vegetation cover, topographic complexity (TC) and rivers, with western facing slopes, topographic complexity and rivers restricting gene flow. In general, thicket vegetation was correlated with increased gene flow. Identifying features of the landscape that facilitate movement/dispersal in M. natalensis potentially has application for other small mammals in similar ecosystems. As the primary reservoir host of the zoonotic Lassa virus, a landscape genetics approach may have applications in determining areas of high disease risk to humans. Identifying these landscape features may also be important in crop management due to damage by rodent pests.


Assuntos
Ecossistema , Fluxo Gênico/genética , Genética Populacional , Febre Lassa/epidemiologia , Animais , Reservatórios de Doenças/virologia , Humanos , Febre Lassa/transmissão , Vírus Lassa/patogenicidade , Murinae/genética , Murinae/virologia , África do Sul/epidemiologia
19.
Parasit Vectors ; 8: 581, 2015 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-26552398

RESUMO

BACKGROUND: Lack of effective vaccines and therapeutics for important arboviral diseases such as Rift Valley fever (RVF) and dengue, necessitates continuous monitoring of vector populations for infections in them. Plant-based lures as surveillance tools has the potential of targeting mosquitoes of both sexes and females of varied physiological states; yet such lures are lacking for vectors of these diseases. Here, we present evidence of the effectiveness of linalool oxide (LO), a single plant-based lure previously developed for malaria vectors in trapping RVF vectors, Aedes mcintoshi and Aedes ochraceus, and dengue vector, Aedes aegypti. METHODS: For RVF vectors, we used CDC traps to evaluate the performance of LO against three vertebrate-based lures: CO2 (dry ice), BioGent (BG) lure, and HONAD (a blend of aldehydes) in 2 experiments with Completely Randomized design: 1) using unlit CDC traps baited separately with LO, HONAD and BG-lure, and unlit CDC trap + CO2 and lit CDC trap as controls, 2) similar treatments but with inclusion of CO2 to all the traps. For dengue vectors, LO was evaluated against BG lure using BG sentinel traps, in a 3 × 6 Latin Square design, first as single lures and then combined with CO2 and traps baited with CO2 included as controls. Trap captures were compared between the treatments using Chi square and GLM. RESULTS: Low captures of RVF vectors were recorded for all lures in the absence of CO2 with no significant difference between them. When combined with CO2, LO performance in trapping these vectors was comparable to BG-lure and HONAD but it was less effective than the lit CDC trap. In the absence of CO2, LO performed comparably with the BG-lure in trapping female Ae. aegypti, but with significantly higher males recorded in traps baited with the plant-based lure. When CO2 was added, LO was significantly better than the BG-lure with a 2.8- fold increase in captures of male Ae. aegypti. CONCLUSIONS: These results highlight the potential of LO as a generalist plant-based lure for mosquito disease vectors, pending further assessment of possible specificity in their response profile to the different stereoisomers of this compound.


Assuntos
Aedes/efeitos dos fármacos , Cicloexanóis/farmacologia , Vetores de Doenças , Monoterpenos/farmacologia , Feromônios/farmacologia , Compostos de Tritil/farmacologia , Monoterpenos Acíclicos , Animais , Distribuição Aleatória
20.
Zookeys ; (523): 89-97, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26478700

RESUMO

The genus Afromantispa Snyman & Ohl, 2012 was recently synonymised with Mantispa Illiger, 1798 by Monserrat (2014). Here morphological evidence is presented in support of restoring the genus Afromantispa stat. rev. to its previous status as a valid and morphologically distinct genus. Twelve new combinations (comb. n.) are proposed as species of Afromantispa including three new synonyms.

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