Papers by Désirée Chantal Aléné
International Journal of Biological and Chemical Sciences, Oct 28, 2023
Pepper is a vegetable which plays an important role in the human diet and health. Many insects at... more Pepper is a vegetable which plays an important role in the human diet and health. Many insects attack this plant and decrease its production in the absence of appropriate phytosanitary treatment. Thus, the objective of the present study was to record the arthropods associated with the yellow and red pepper varieties. For this purpose, weekly observations were conducted during two cropping cycles on 192 plants, using a completely randomized device. As results, the fauna of the pepper was very diverse and stable (specific richness 47 and Equitability index 0.86). The yellow pepper was the most sensitive with an average of nine insect species per plant versus eight on the red pepper. These insects belonged to seven orders (Arachnida, Coleoptera, Diptera, Hemiptera, Hymenoptera, Lepidoptera and the Orthoptera), 28 families and 47 species. The densest orders were Diptera represented by Ceratitis capitata, Silba capsicarum, followed by Hymenoptera were represented by Camponotus floridanus, Camponotus acvapimensis and Crematogaster sp. and Hemiptera represented by Aphis gossypii, Macrosiphum euphorbiae, Pseudococcus sp. The present study provided a database on arthropodofauna of the pepper plant. This is of paramount importance for the development of healthy and sustainable protection strategies among pepper producers in order to improve national production.
Phylogeny and classification of jumping plant lice of the subfamily Liviinae (Hemiptera: Psylloidea: Liviidae) based on molecular and morphological data
Zoological Journal of the Linnean Society
Using molecular (COI, Cytb, H3, wg, 12S, 16S, and 28S) and morphological data (61 characters of a... more Using molecular (COI, Cytb, H3, wg, 12S, 16S, and 28S) and morphological data (61 characters of adults and immatures), the phylogenetic relationships of the 20 nominal genera of Liviinae were analysed, and the monophyly of the subfamily was tested relative to the other two subfamilies of Liviidae. The analyses of the molecular, morphological, and combined datasets provided similar results with a strong or moderate support in the molecular and combined analyses for the subfamilies of Liviidae and two clades in Liviinae given tribal rank (Liviini and Paurocephalini stat. rev.). Three of the six previously recognized genera were confirmed as monophyletic (Aphorma, Camarotoscena, and Livia) and three were shown to be polyphyletic: Diclidophlebia s.l. (Diclidophlebia s.s., Haplaphalara stat. rev., Klyveria Burckhardt, Serbina and Malenovský, gen. nov., Melanastera Serbina, Malenovský, Queiroz and Burckhardt, gen. nov. and Woldaia stat. rev.), Paurocephala s.l. (Liella Burckhardt, Serbina...
American Journal of BioScience, Jul 6, 2023
The study on the temporal fluctuation of populations and damage caused by Leucinodes orbonalis on... more The study on the temporal fluctuation of populations and damage caused by Leucinodes orbonalis on African eggplant (Solanum aethiopicum) fruits was carried out in the forest region of South Cameroon from June 11 to September 22, 2018. It consisted of incubations of the attacked fruits in the laboratory for the study of L. orbonalis abundances and the evaluation of the damage caused by the same pest directly in the field and during each harvest; followed by the correlations with abiotic factors. The results showed that out of 331 incubated fruits for 06 harvests and 02 seasons of study, the average number of adults / fruit of L. orbonalis varied significantly from one harvest to another (F (5, 325) = 27.038, p <0.001) with a peak of 4.37 ± 0.66 individuals / fruit (N= 2) at the 2nd harvest (in August), and season to season (F (1, 329) = 15.002, p <0.001) with a peak of 3.22 ± 0.48 individuals / fruit (N=31) during the short dry season. Damage on S. aethiopicum fruits varied significantly from one harvest to another (F (5, 325) = 27.038, p <0.001) with a peak of 13.05 ± 4.10% in the first week of harvest in August. This damage did not change from one season to another (p <0.659). Means weight, length and diameter of an incubated fruit varied significantly from one harvest to another (F (5, 325) = 5,893; F (5, 325) = 7.71 and F (5, 325) = 7.84; p <0.001 respectively). The highest means weight, length and diameter were obtained at the 2nd and 3rd harvest with average values of 36.15 ± 6.87g and 40.20 ± 4.40g for the mean weight; 4.03 ± 0.30cm and 3.86 ± 0.15cm for the mean length and 4.15 ± 0.34cm and 4.12 ± 0.20cm for the mean diameter. Study revealed that the mean number of L. orbonalis per fruit had a significant positive correlation with mean weight (r=0.39, p <0.01), mean length (r=0.40, p <0.001) and mean diameter (r=0.41, p <0.001) of attacked fruits and multiple regression equations of y=5.3302x+16.021, R 2 =0.8172; y=0.3103x+2.6544, R 2 =0.8194 and y=0.3684x+2.6037, R 2 =0.8664 of weight, length and diameter respectively. Field damage showed a positive and non-significant correlation with precipitation (r = 0.80, p <0.20) and a negative and non-significant correlation with mean temperature (r =-0.737, p <0.262) and mean relative humidity (r =-0.632, p <0.367). These results are of practical significance in designing appropriate strategies for L. orbonalis control in eggplant intercropping systems.
International Journal of Biological and Chemical Sciences, Sep 13, 2019
Tritrophic plant-hemipteran-ant relationships are poorly documented in tropical African market-ga... more Tritrophic plant-hemipteran-ant relationships are poorly documented in tropical African market-garden agro-systems despite its agronomic importance. The present study aimed at characterizing ant-hemipteran associations on five market crop species at Nkolondom (north-western suburb of Yaoundé): Abelmoschus esculentus, Capsicum annum, Solanum lycopersicum, Solanum melongena and Solanum scabrum. From July to October 2013, twice per week, feeding activities of ants were examined and the occurrence of each ant/hemipteran association recorded per plant species. As result, ants preferentially harvested honeydew excreted by hemipterans. However, Myrmicaria opaciventris and Camponotus flavomarginatus also collected plant sap from wounded organs. Among hemipterans, Aphis fabae, Aphis gossypii, Aulacorthum solani, Macrosiphum euphobiae, scale insects and mealybugs were the most recurrent. The most frequent associations were M. opaciventris-A. fabae and C. flavomarginatus-A. fabae on S. scabrum, C. flavomarginatus-M. euphorbiae on S. lycopersicum, C. flavomarginatus-A. solani on C. annuum, M. opaciventris-A. gossypii and Technomyrmex sp.-A. gossypii on S. lycopersicum. Some moderately frequent associations viz. C. flavomarginatus-M. euphorbiae and M. opaciventris-M. euphorbiae were recorded on S. melongena. For these associations, highly significant and positive correlations was raised between ants' and aphids' populations, suggesting potential mutualistic interactions between the two taxa.
Fruits, Jul 1, 2006
Article original Influence of shade on the sensitivity of seedlings of Ricinodendron heudelotii (... more Article original Influence of shade on the sensitivity of seedlings of Ricinodendron heudelotii (Baill.) to attacks of Diclidophlebia xuani Messi et al. in the natural environment in Cameroon. Abstract-Introduction. Ricinodendron heudelotii (Euphorbiaceae), in the process of domestication in Cameroon, is a wild fruit-bearing tree with edible oleaginous kernels. In the natural environment or seedbed, the young seedlings are destroyed by a psyllid, Diclidophlebia xuani (Hemiptera: Psyllidae). Materials and methods. The incidence of the damage caused by this pest under natural conditions was evaluated on less than 3-month-old seedlings, in shaded medium and medium without shade. The data were collected in two sites of the surroundings of Yaounde, Nkolondom and Nkozoa, between April and May 2000. Results and discussion. The results showed that the index of damage was higher in Nkolondom than in Nkozoa, probably due to the higher number of seedlings in the first site compared with the second; whatever the site, the damage was more spectacular in medium without shade than in shaded medium; the damage also increased with the stage of development of the seedling until it was completely destroyed before reaching 4 months old. Conclusion. Ultimately, the seedlings of R. heudelotii are more sensitive to the depredations of the psyllid when they grow in medium without shade. Cameroon / Ricinodendron heudelotii / insect control / Diclidophlebia xuani / damages / site factors / shading Influence de l'ombrage sur la sensibilité des plantules de Ricinodendron heudelotii (Baill.) aux attaques de Diclidophlebia xuani Messi et al. en milieu naturel au Cameroun. Résumé-Introduction. Ricinodendron heudelotii (Euphorbiaceae), en voie de domestication au Cameroun, est un arbre fruitier sauvage aux amandes oléagineuses comestibles. En milieu naturel ou en pépinière, les plantules sont détruites par Diclidophlebia xuani (Hemiptera : Psyllidae). Matériel et méthodes. L'incidence des dégâts causés par ce ravageur dans les conditions naturelles a été évaluée sur des plantules âgées de moins de 3 mois, en milieu ombragé et en milieu sans ombrage. Les données ont été collectées dans deux sites des environs de Yaoundé entre avril et mai 2000. Résultats et discussion. L'analyse des résultats a montré que les indices de dégâts du psylle ont été plus élevés à Nkolondom qu'à Nkozoa, probablement à cause du nombre plus élevé de plantules dans le premier site que dans le deuxième ; quel que soit le site, les dégâts ont été plus spectaculaires en milieu sans ombrage qu'en milieu ombragé ; les dégâts ont également augmenté avec le développement de la plantule jusqu'à ce qu'elle soit complètement détruite avant d'atteindre quatre mois. Conclusion. En définitive, les plantules de R. heudelotii sont plus sensibles aux déprédations du psylle lorsqu'elles se développent en milieu sans ombrage. Cameroun / Ricinodendron heudelotii / lutte anti-insecte / Diclidophlebia xuani / dégâts / facteurs liés au site / ombrage
The Immatures and Host Plant Range of theFicus-Feeding Jumping Plant-LouseHomotoma eastopi(Hemiptera: Psylloidea) in Southern Cameroon
African Entomology, Dec 1, 2014
ABSTRACT Homotoma eastopi Hollis&amp;Broomfield 1989, previously described from Bamenda (Nort... more ABSTRACT Homotoma eastopi Hollis&amp;Broomfield 1989, previously described from Bamenda (Northwest Region, Cameroon) with unknown immatures and host plants is presently reported from Yaounde (Centre Region, Cameroon), on several species of the genus Ficus on which adults and immatures feed. The last instar immature is described and illustrated; taxonomically relevant morphological details of the adults are illustrated, especially on the head, and male and female terminalia. The host plant range and information on its biology are also given.
Infestation of<i>Heteropsylla cubana</i>(Hemiptera: Psylloidea) on<i>Leucaena leucocephala</i>(Fabaceae: Mimosoideae) in Cameroon
African Entomology, Sep 1, 2012
Leucaena leucocephala (Fabaceae: Mimosoideae), originating from Central America, was introduced i... more Leucaena leucocephala (Fabaceae: Mimosoideae), originating from Central America, was introduced into Cameroon in the 1960s as a shade tree and for soil improvement. The tree is strongly infested by Heteropsylla cubana (Hemiptera: Psyllidae), also native to Central America. The purpose of this study is to record the presence of the psyllid in Cameroon, and assess its infestation pattern in order to provide the necessary data for an integrated pest management strategy. Data were collected at two sites, Koutaba (Western Highlands) and Yaounde (Southern Plateau), respectively, with three plots (K1, K2, K3) at the former site and one (Y) at the latter. The relative abundance of psyllids varied significantly between the four plots (K = 97.6, d.f. = 3, P < 0.0001). The Yaounde plot with a mean of 4013.71 individuals/100 leaves was more infested than any of those in Koutaba (with 1888.10, 314.60 and 2546.92 individuals/100 leaves, respectively). At both sites, the spatial distribution of psyllid populations globally followed an aggregated pattern with the dispersion index k ranging from 0.082 to 5.32. The infestation rate observed was influenced by plot age rather than climatic factors. In fact, the Yaounde plot was younger than those in Koutaba.
African Invertebrates, Dec 1, 2011
BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access t... more BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.
Diaphorina pfanderae Aléné and Burckhardt sp. nov. (Hemiptera: Psylloidea: Psyllidae) and its association with ants on Ozoroa pulcherrima (Anacardiaceae)
Journal of Natural History, Jul 18, 2021
ABSTRACT Diaphorina (Psyllidae: Diaphorininae) is a large Old World genus with an unusually wide ... more ABSTRACT Diaphorina (Psyllidae: Diaphorininae) is a large Old World genus with an unusually wide range of host plants. Its most prominent member is undoubtedly the Asian citrus psyllid, Diaphorina citri, one of the most devastating citrus pests in tropical Asia and the New World where it is adventive. Recently, the species also was discovered in Africa where it appears to be spreading quickly. Detection and correct identification is difficult due to the presence of over 50 described and many undescribed native species. Morphological differences between species are small, and there are no diagnosable species groups (with one exception: the Diaphorina amoena group). Here we define a second, putatively monophyletic species group, the Diaphorina albomaculata group, consisting of six Afrotropical species. In two of the species, it was observed that the immatures were tended by ants. One of the members of the D. albomaculata group is Diaphorina pfanderae Aléné and Burckhardt sp. nov., developing on Ozoroa pulcherrima (Anacardiaceae) in West Cameroon. Here, adults and immatures are described and diagnosed with illustrations. Diaphorina pfanderae differs from the other species of the D. albomaculata group in the fore wing pattern and details of the male and female terminalia as well as details of the chaetotaxy in immatures. Keys are provided for the identification of the adults and last-instar immatures of the species of the D. albomaculata group. Immatures of D. pfanderae showed a preference for young leaves, a characteristic shared by other psyllids. The species has always been associated with the three ant species Camponotus congolensis, C. flavomarginatus and Crematogaster sp. (Hymenoptera: Formicidae). The first two species often build soil shelters around the psyllid colonies situated on twigs, stems or leaves of O. pulcherrima. urn:lsid:zoobank.org:pub:4418BAB6-B6B7-459C-B75E-9CDC8971E054
Fruits, Jul 1, 2005
Note technique Some aspects of the biology of Diclidophlebia xuani Messi et al. (Hemiptera: Psyll... more Note technique Some aspects of the biology of Diclidophlebia xuani Messi et al. (Hemiptera: Psyllidae), a pest of Ricinodendron heudelotii Baill. (Euphorbiaceae) in Cameroon. Abstract-Introduction. Ricinodendron heudelotii Baill. is a forest species in the domestication process in Cameroon where the plant is appreciated for its food, ecological and medicinal virtues. The damage caused by the psyllid Diclidophlebia xuani Messi et al. to the young seedlings, in the seedbed or after their plantation, constitutes one of the principal constraints to the domestication of the species. The pest biology was thus studied in order to consider its control. Materials and methods. Various aspects of the biology of D. xuani were approached: the copulation process, choice of the egg-laying site by the female, sexual maturation of the adults, female fecundity, adult longevity, embryonic and larval development, sex ratio when emerging and food specificity. The experiments took place in the area of Yaounde either in the field, or in a controlled environment during the years 2001 and 2002. Results and discussion. The males of D. xuani emerged before the females and the mating took place approximately 15 min after the imaginal moult. The longevity of the females was 29 days on average, and that of the males, 7 days. Laying began 3 days after emergence and continued until the end of the female lifetime. In a hot period (28 °C approximately), a female laid on average 532 eggs during its lifetime; in a period of low temperatures (24 °C to 26 °C approximately), average fecundity was of 758 eggs. The eggs are essentially laid on the youngest leaves of R. heudelotii. The average duration of the embryonic and larval developments lasted approximately 7 days and 22 days, respectively. The life cycle, from egg to egg, required 32 days on average. The sex ratio was close to 1. Conclusion. D. xuani entirely develops, without interruption, on R. heudelotii; it has never been observed on other plant species. It thus appears to be closely associated with this plant. Cameroon / Ricinodendron heudelotii / Diclidophlebia xuani / longevity / copulation / fecundity / life cycle / sex ratio Quelques aspects de la biologie de Diclidophlebia xuani Messi et al. (Hemiptera : Psyllidae), ravageur de Ricinodendron heudelotii Baill. (Euphorbiaceae) au Cameroun. Résumé-Introduction. Ricinodendron heudelotii Baill. est une essence forestière en voie de domestication au Cameroun où la plante est appréciée pour ses vertus alimentaires, écologiques et médicinales. Les dégâts causés par le psylle Diclidophlebia xuani Messi et al. aux jeunes plants, en pépinière ou après leur plantation, constituent l'une des principales contraintes à la domestication de l'espèce. La biologie de ce ravageur a donc été étudiée afin d'envisager son contrôle. Matériel et méthodes. Différents aspects de la biologie de D. xuani ont été abordés : processus d'accouplement, choix du site de ponte par la femelle, maturation sexuelle des imagos, fécondité des femelles, longévité des imagos, développement embryonnaire et larvaire, sex-ratio à l'émergence et spécificité alimentaire. Les expérimentations ont eu lieu dans la région de Yaoundé soit en champ, soit en milieu contrôlé durant les années 2001 et 2002. Résultats et discussion. Les mâles de D. xuani ont émergé avant les femelles et le rapprochement des sexes a eu lieu 15 min environ après la mue imaginale. La longévité des femelles a été de 29 jours en moyenne, celle des mâles, de 7 jours. La ponte a commencé 3 jours après l'émergence et s'est poursuivie jusqu'à la fin de la vie de la femelle. En période chaude (28°C environ), une femelle a pondu en moyenne 532 oeufs pendant toute sa vie ; en période de basses températures (24°C à 26 °C environ), la fécondité moyenne a été de 758 oeufs. Les oeufs sont essentiellement déposés sur les étages foliaires les plus jeunes de R. heudelotii. Les développements embryonnaire et larvaire ont duré respectivement 7 jours et 22 jours environ. Le cycle de développement, d'oeuf à oeuf, a nécessité 32 jours en moyenne. Le sex-ratio a été proche de 1. Conclusion. D. xuani se développe entièrement et sans interruption sur R. heudelotii ; il n'a jamais été rencontré sur d'autres espèces de plantes. Il serait donc étroitement associé à cette plante.
African Journal of Agricultural Research, Mar 12, 2015
Tomato and pepper are two major market gardening crops in Cameroon. In order improve pest insects... more Tomato and pepper are two major market gardening crops in Cameroon. In order improve pest insects control strategies, we assessed their diversity and evaluated their impact on yield losses in two agroecological areas of southern Cameroon. To achieve this, estimations of damages by visual observations were done twice per month from March 2010 to February 2011, in trap gardens set up respectively at Koutaba (Western Highlands) and at Okola (Southern Plateau). During each sampling, all fruits present in the garden were counted, those attacked or fallen on the ground collected and incubated in the laboratory for pest identification needs. Seven insect pests species belonging to two orders were identified. Among them, Dacus punctatifrons (Diptera-Tephritidae) and, Chrysodeixis chalcites (Lepidoptera-Noctuidae) were recorded on tomato, Ceratitis capitata (Diptera-Tephritidae), Chryptophlebia leucotreta and Leucinoides orbonalis (Lepidoptera-Pyralidea) on pepper while Spodoptera littoralis, and Helicoverpa armigera (Lepidoptera-Noctuidae) were recorded on both plants species. Fruit loses related to insects' activities were greater in Koutaba (43-47%) than they were at Okola (28-33%). These rates varied with seasons. For instance, frequencies of fruits affected by D. punctatifrons, C. capitata, C. leucotreta were positively correlated to the abiotic factors, especially temperature and rainfall.
Relation between ground‐dwelling and arboreal ant diversity in three vegetation types in the humid forest zone of southern Cameroon
African Journal of Ecology
Computational Biology and Bioinformatics, 2021
Prey fragmentation and transport modalities were studied in Myrmicaria opaciventris, Platythyrea ... more Prey fragmentation and transport modalities were studied in Myrmicaria opaciventris, Platythyrea conradti, Cremtogaster sp., Crematogaster clariventris, Tetramorium aculeatum and Oecophylla longinoda, six tropical ant species with varying levels of adaptation to foraging in the tree canopy. Termites and grasshoppers of different sizes were used as prey and deposited on a hunting arena. After prey capture, we investigated the strategy adopted by each ant species to fragment and transport their prey. The data were analyzed with classification tree, using Chi-squared Automatic Interaction Detection method to find the variation in prey fragmentation strategies and transportation modalities between arboreal ant species in relation with prey type and prey size. The results showed that prey fragmentation did not occur systematically after capture and varied between ant species with prey type and prey size. Studied ant species cut their prey either completely into tiny pieces or partially into two or three large pieces before cutting them totally into tiny pieces or not at all. Fragmentation strategy, induced variation in transport modalities including (a) transport of large pieces, each by a single worker; (b) transport of large pieces, each, by a group of workers; (c) transport of tiny pieces after total cutting, and (c) transport of entire prey in the nest without fragmentation. Prey fragmentation and transport modalities varied between ant species in relation with their level of adaptation to arboreal area.
Spatial pattern in arboreal ant community at Mfou suburban agglomeration around Yaoundé city, Cameroon
Community Ecology, 2021
Ant community structure in natural and anthropogenic ecosystems depends on the combination of sev... more Ant community structure in natural and anthropogenic ecosystems depends on the combination of several factors not easy to elucidate according to the complexity of habitat structures and anthropogenic disturbances. We investigated the influence of tree distribution pattern on the spatial distribution of dominant ant species, and the spatial relationship between dominant and associated ant species in secondary forest, cocoa farms, and palm groves at Mfou around Yaounde city. Nine plots of 30 × 30 m each were set up around the study area including three each from every habitat type. Each plot was mapped and the Cartesian coordinated of each tree was recorded. Ants were collected on the trees using a pitfall trap and visual catch. The spatial distribution pattern of the trees and numerical dominant species were analyzed using Besag’s function and spatial relationship between numerical dominant and associated ant species with pair correlation function. Trees distribution fits random mode...
A comparative assessment on ant communities in three vegetation types located at Mfou Suburban locality of Yaoundé (Cameroon)
Journal of Insect Biodiversity, 2021
Urban expansion in Cameroon and many other Congo basin countries, involves the destruction of nat... more Urban expansion in Cameroon and many other Congo basin countries, involves the destruction of natural habitat previously colonized by a rich and diversified invertebrate and vertebrate fauna. In order to understand the dynamic of transformation of natural landscape into urban area on ant communities, a study was conducted at Mfou, a suburban agglomeration of Yaoundé. We aimed to evaluate the variation in ant diversity and ant community structure in relation to the type of habitat. Ants were collected on the ground and trees in cocoa farms, secondary forests, and palm groves using visual catch, pitfall traps, quadrat, and baits. We recorded 144 species belonging to 39 genera and 6 subfamilies. Cocoa farms (S= 102; H’= 3.83; E=0.83) were richer and more diversified than secondary forests (S= 100; H’= 3.83; E=0.83) and palm groves (S= 70; H’= 3.61; E=0.85). Myrmicinae, Formicinae and Ponerinae were the richest subfamilies both at genus and species levels. Based on their frequency of oc...
Journal of Insect Behavior, 2019
We examined the recruitment rate of nestmates during prey capture in six arboreal ant species: My... more We examined the recruitment rate of nestmates during prey capture in six arboreal ant species: Myrmicaria opaciventris, Platythyrea conradti, Crematogaster sp., Crematogaster clariventris, Tetramorium aculeatum, and Oecophylla longinoda. Termites and grasshoppers were used as prey. Prey were grouped by size: for termites, we presented ants with either workers or soldiers and for grasshoppers, we used small nymphs, mature nymphs and adults. After prey detection by a foraging ant, the total recruits present were counted every 30 s over the course of 15 min, and the mean numbers of workers counted at each time interval was computed and plotted for each prey type. We tested the effect of prey type, prey size and termite caste for each ant species on the number of nestmates recruited using ANOVA (GLM proc). Prey size, prey type and termite caste significantly influenced the mean number of nestmates following initial prey detection. We found that the observed recruitments were well explained by linear models for less arboreal (M. opaciventris) and primitive arboreal species (P. conradti), reflecting stochastic movement by individuals or stochastic collective recruitment. For specialized arboreal ant species, recruitment was well explained by exponential models, reflecting withingroup recruitment, either with limited or with unlimited group sizes. Overall, T. aculeatum had the highest level of nestmate recruitment. Surprisingly, O. longinoda, known to be one of the most specialized arboreal ant species, fit a recruitment model more like that of either ground ants with some arboreal foraging habits or primitive arboreal species.
Ant assemblage structure on cocoa trees in smallholder farms in the Centre Region of Cameroon
African Journal of Ecology, 2019
We investigated the ant community structure in cocoa farms in the Centre Region of Cameroon. Ants... more We investigated the ant community structure in cocoa farms in the Centre Region of Cameroon. Ants were collected on the cocoa trees during the years 2006 and 2007 using chemical knock‐down. We tested the hypothesis of the existence of deterministic factor in the structuration of ant mosaic using C‐Score; we assessed the relationship between the numerical dominant and subdominant ant species using Spearman correlation test and discussed on the influence of vegetation structure and farm management on the ant community structure. A total of 53 ant species belonging to 20 genera and five subfamilies were identified from a set of 51,525 workers collected. C‐score analysis supported the hypothesis that ant community were structured by competition. Negative relationships were found between dominant ant species. Farming practices which were mainly pruning, chemical treatment and habitat structure appeared to influence the ecological status and distribution of dominant ant species.
Figure 4 in Diaphorina pfanderae Aléné and Burckhardt sp. nov. (Hemiptera: Psylloidea: Psyllidae) and its association with ants on Ozoroa pulcherrima (Anacardiaceae)
Figure 4. Diaphorina pfanderae Aléné and Burckhardt sp. nov., terminalia and egg. (a) Male termin... more Figure 4. Diaphorina pfanderae Aléné and Burckhardt sp. nov., terminalia and egg. (a) Male terminalia, in profile; (b) inner face of paramere; (c) distal two segments of aedeagus; (d) female terminalia, in profile; (e) section of circumanal ring; (f) egg, in profile.
Figure 1 in Diaphorina pfanderae Aléné and Burckhardt sp. nov. (Hemiptera: Psylloidea: Psyllidae) and its association with ants on Ozoroa pulcherrima (Anacardiaceae)
Figure 1. Host plant, habitat and associated ants of Diaphorina pfanderae Aléné and Burckhardt sp... more Figure 1. Host plant, habitat and associated ants of Diaphorina pfanderae Aléné and Burckhardt sp. nov. (a) Ozoroa pulcherrima; (b) study site; (c, d) immatures with Camponotus congolensis.
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Papers by Désirée Chantal Aléné