Large-scale mitochondrial DNA analysis of native honey bee Apis mellifera populations reveals a new African subgroup private to the South West Indian Ocean islands

Background: The South West Indian Ocean (SWIO) archipelagos and Madagascar constitute a hotspot of biodiversity with a high rate of endemism. In this area, the endemic subspecies A. m. unicolor has been described in Madagascar. It belongs to the African lineage, one of the four described evolutionary lineages in honey bees. Despite a long beekeeping tradition and several recorded European introductions, few studies have been carried out on the diversity and proportion of honey bee subspecies. In order to identify and define which evolutionary lineages and potential sub-lineages are present in the SWIO, the COI-COII intergenic region and the ND2 gene of the mtDNA were sequenced in honey bee colonies from three archipelagos. An extensive sampling (n = 1184 colonies) was done in the Mascarene (La Réunion, Mauritius, Rodrigues), Seychelles (Mahé, Praslin, La Digue) and Comoros (Grande Comore, Mohéli, Anjouan, Mayotte) archipelagos. Islands genetic diversity was compared to newly sampled populations from Madagascar, continental African and European populations. Results: African lineage haplotypes were found in all islands (except for Rodrigues). Madagascar, Comoros and Seychelles had 100% of A lineage, 95.5% in La Réunion and 56.1% in Mauritius. Among all African colonies detected in the SWIO, 98.1% (n = 633) of COI-COII haplotypes described the presence of the subspecies A. M. unicolor. Both genetic markers revealed i) a new private AI mitochondrial group shared by the SWIO archipelagos and Madagascar distant from continental populations; ii) the private African haplotypes for each island suggested diversity radiation in the archipelagos; iii) the detection of the Comoros archipelago as a possible contact area between insular and continental African populations. The exotic European C and M lineages were only detected in the Mascarene archipelago, but striking differences of proportion were observed among islands. Merely 4.6% of European colonies were found in La Réunion whereas Mauritius cumulated 44%. Here, among the 84 observed COI-COII haplotypes, 50 were newly described including 13 which were private to the SWIO archipelagos and Madagascar. Similarly, 24 of the 34 found ND2 haplotypes were novel which included six haplotypes particular to the SWIO populations. Conclusion: A new African subgroup was described in the SWIO region with mitochondrial genetic evidence that A. m. unicolor is the indigenous subspecies of the archipelagos surrounding Madagascar. (Résumé d'auteur

Trois espèces de Cochenilles potentiellement invasives nouvelles pour l’île Maurice (Hemiptera, Coccoidea, Pseudococcidae)

Three species of potentially invasive scale insects new for Mauritius (Hemiptera, Coccoidea, Pseudococcidae). Three invasive scale insects are newly recorded on Mauritius : Paracoccus marginatus Williams & Granara de Willink, 1992, Phenacoccus solenopsis Tinsley, 1898, and Planococcus kenyae (Le Pelley, 1935).Trois espèces de Cochenilles invasives sont nouvellement citées pour l’île Maurice : Paracoccus marginatus Williams & Granara de Willink, 1992, Phenacoccus solenopsis Tinsley, 1898, et Planococcus kenyae (Le Pelley, 1935).Germain Jean-François, Sookar Preeaduth, Buldawoo Indranee, Permalloo Shradhanand, Quilici Serge. Trois espèces de Cochenilles potentiellement invasives nouvelles pour l’île Maurice (Hemiptera, Coccoidea, Pseudococcidae). In: Bulletin de la Société entomologique de France, volume 119 (1),2014. pp. 27-29

Trois espèces de Cochenilles potentiellement invasives nouvelles pour l’île Maurice (Hemiptera, Coccoidea, Pseudococcidae)

Three species of potentially invasive scale insects new for Mauritius (Hemiptera, Coccoidea, Pseudococcidae). Three invasive scale insects are newly recorded on Mauritius : Paracoccus marginatus Williams & Granara de Willink, 1992, Phenacoccus solenopsis Tinsley, 1898, and Planococcus kenyae (Le Pelley, 1935).Trois espèces de Cochenilles invasives sont nouvellement citées pour l’île Maurice : Paracoccus marginatus Williams & Granara de Willink, 1992, Phenacoccus solenopsis Tinsley, 1898, et Planococcus kenyae (Le Pelley, 1935).Germain Jean-François, Sookar Preeaduth, Buldawoo Indranee, Permalloo Shradhanand, Quilici Serge. Trois espèces de Cochenilles potentiellement invasives nouvelles pour l’île Maurice (Hemiptera, Coccoidea, Pseudococcidae). In: Bulletin de la Société entomologique de France, volume 119 (1),2014. pp. 27-29

When European meets African honeybees (Apis mellifera L.) in the tropics: Morphological changes related to genetics in Mauritius Island (South-West Indian Ocean)

International audienceThe previous genetic characterization of the honeybee population of Mauritius Island (Indian Ocean) revealed an ongoing process of hybridization between the first established African subspecies Apis mellifera unicolor and recently imported European subspecies (A. m. ligustica, A. m. carnica and A. m. mellifera). This context offers the rare opportunity to explore the influence of hybridization between African and European honeybees on phenotypic traits out of the case largely studied of the Africanized honeybee (hybrid between A. m. scutellata from South Africa and European subspecies). We thus conducted geometric morphometric analyses on forewings of 283 workers genetically characterized at 14 microsatellite loci to evaluate (1) if the morphological variability coincides well with the neutral genetic variability, (2) if hybrids exhibited rather parental, intermediate or transgressive traits, and (3) to test if fluctuating asymmetry (FA) of size and shape, as a measure of developmental stability, was elevated in hybrids (due to genetic stress) and/or European bees (due to unsuitable environment) compared to African bees. A strong concordance was found between morphological variability and neutral genetic variability, especially for wing shape, based on partial least-square analyses (PLS). However, on average, the morphology of hybrids was more similar to the African bees, potentially reflecting the dynamics and direction of introgression. Significant FA for wing size as well as wing shape was detected, suggesting the overall presence of stress during the development of the studied individuals. In contrast, the asymmetry levels do not differ according to the ancestry (African, European or hybrid) of the individuals. Therefore, if ongoing hybridization contributed to increasing the genetic and phenotypic diversity of the populations and influences its adaptive potential, developmental stressors could not be identified and their evolutionary consequences remain uncertain

Distribution and genetic diversity of five invasive pests of Eucalyptus in sub-Saharan Africa

Eucalyptus is one of the most planted tree genera across the world, but is heavily challenged by invasive insect pests originating from the native range of these trees. The rate of introduction of non-native Eucalyptus-feeding insects has increased globally, including in sub-Saharan Africa where Eucalyptus trees have an important socio-economic role. In this study, we mapped the distribution and examined the genetic diversity of non-native Eucalyptus insect pests in 14 countries across sub-Saharan Africa. We focused on five foliage-feeding insect pests of Eucalyptus which are known to be present in the region, namely the bluegum chalcid wasp, Leptocybe invasa; the redgum lerp psyllid, Glycaspis brimblecombei; the bronze bug, Thaumastocoris peregrinus; the Eucalyptus weevil, Gonipterus sp.n.2; and the Eucalyptus gall wasp, Ophelimus maskelli. Insect samples were collected through structured surveys and small-scale sampling which were both combined with published literature to determine the distribution of these insect pests. Genetic diversity of each of these insect pests was estimated/assessed based on mitochondrial cytochrome oxidase I (COI) or cytochrome b (Cyt b) sequence data. Except O. maskelli, which is a relatively recent arrival, the other insect pests were found broadly distributed across the sampled countries, with first reports in many countries. Analysis of genetic diversity confirmed a common origin of geographically distant populations for G. brimblecombei and O. maskelli, moderate diversity for T. peregrinus and Gonipterus sp.n.2 and at least two distinct lineages for L. invasa. Two divergent haplogroups of L. invasa, with overlapping geographic range were confirmed in Ghana, Malawi, Sierra Leone, South Africa and Zimbabwe. Compared to published literature, new haplotypes were detected for T. peregrinus, Gonipterus sp.n.2 and L. invasa, suggesting multiple introduction of those pests in the region. Results of this study will have implications for quarantine, management and future research of Eucalyptus insect pests in the region and beyond.Supplementary material ESM 1 : Sample collection localities and number of insect used in this study.Members of Tree Protection Cooperative Program (TPCP), Centre for Tree Health Biotechnology (CTHP), Sustainable Afforestation Association (SAA), MIRO Forestry Company, The Food and Agriculture Organization of the United Nation (FAO), the European Union: European regional development fund (ERDF, INTERREG V program), the Conseil Re´gional de la Re´union, the Centre de Coope´ration internationale en Recherche agronomique pour le De´veloppement (CIRAD) and Ethiopian Environment and Forest Research Institute (EEFRI).http://link.springer.com/journal/105302021-03-28hj2020BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologyZoology and Entomolog