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On a global scale, invasive grasses threaten biodiversity and ecosystem function. Nevertheless, the importation of forage grasses is a significant economic force driven by globalization. Pastureland and rangeland are of critical economic and ecological importance, but novel grass species may lead to invasion. Recognizing that economically important species can also be ecologically damaging creates a contentious debate for land managers, policymakers, and ecologists alike. Many Afrotropical perennial grass species have been intentionally introduced pantropically given their high forage production and resistance to stress. However, these traits may also confer competitive ability, increasing the possibility of unintended escape and invasion. Further, these traits have posed challenges for traditional control methods using chemicals, prescribed fire, and mowing. The use of classic biological control may alleviate the ecological impact in invaded areas. In this literature synthesis we examine Guinea grass (Megathyrsus maximus); whose economic value in many countries is undeniable, yet its impact on native ecosystems is a mounting concern. First, we introduce Guinea grass taxonomy, general biology and ecology, and the geographic and genetic origins. Second, we review the economic value and the ecological impacts. Third, we review the control of Guinea grass in undesired areas using chemical and mechanical means. Finally, we review current efforts to use biological control.

The genus Poeonoma (Tams & Bowden, 1953) is revised to include two species P. serrata (Hampson, 1910) and P. ugandensis Le Run. sp., from the Congolian bioregion. Several new synonyms are introduced for Poeonoma serrata: Conicofrontia sjoestedti (Aurivillius, 1925) n. syn. for Poeonoma serrata (Hampson, 1910), Poeonoma similis (Tams & Bowden, 1953) n. syn. for Poeonoma serrata (Hampson, 1910), and Poeonoma nigribasis (Laporte, 1974) n. syn. for Poeonoma serrata (Hampson, 1910). A new genus, Nyaluteme Le Run. gen., is proposed for two species formerly included in Poeonoma, N. acantha (Tams & Bowden, 1953) n. comb. and N. inermis (Laporte, 1973) n. comb., and N. nigra Le Run. sp., described from the Congolian bioregion. Host-plants for three of the species are recorded:Pennisetum purpureum Schumach. for P. serrata and P. ugandensis, and Miscanthus violaceus (K. Schum) Pilg. for N. nigra. A key to species, descriptions, illustrations of adults and genitalia, and distribution maps are included. Results of previously published phylogenetic analyses also allow the status of the new genus to be confirmed and to infer the phylogenetic placement of the two genera.; Le genre Poeonoma (Tams & Bowden, 1953) est révisé ; deux espèces, P. serrata (Hampson, 1910) et P. ugandensis Le Ru n. sp., de la biorégion Congolaise, y sont incluses et plusieurs nouvelles synonymies sont proposées pour Poeonoma serrata : Conicofrontia sjoestedti (Aurivillius, 1925) n. syn. de Poeonoma serrata (Hampson, 1910), Poeonoma similis (Tams & Bowden, 1953) n. syn. de Poeonoma serrata (Hampson, 1910), et Poeonoma nigribasis (Laporte, 1974) n. syn. de Poeonoma serrata (Hampson, 1910). Un nouveau genre, Nyaluteme Le Ru n. gen., de la biorégion Congolaise, est proposé pour deux espèces précédemment décrites dans le genre Poeonoma, N. acantha (Tams & Bowden, 1953) n. comb., et N. inermis (Laporte, 1973) n. comb., et une espèce nouvellement décrite N. nigra Le Ru n. sp. Les plantes-hôtes de trois espèces sont répertoriées : Pennisetum purpureum Schumach. pour P. serrata et P. ugandensis, et Miscanthus violaceus (K. Schum) Pilg. pour N. nigra. Une clé de détermination des espèces est présentée ainsi que l’illustration des adultes et des génitalia et, des cartes de distribution. Les résultats d’analyses de reconstruction phylogénétique déjà publiées permettent également de confirmer le statut du nouveau genre et d’inférer la position phylogénétique des deux genres. http://www.zoobank.org/urn:lsid:zoobank.org:pub:6ED4AC9E-043C-4A04-A92D-807066943002

International audience; The genus Acrapex Hampson, 1891 (Lepidoptera, Noctuidae, Noctuinae, Apameini, Sesamiina) constitutes a speciose group of noctuid stemborers mostly distributed in the Afrotropics. In this study nine new Acrapex species are described: Acrapex abyssinica n. sp., Acrapex dabaga n. sp., Acrapex jansei n. sp., Acrapex kifanya n. sp., Acrapex lusinga n. sp., Acrapex ngwenya n. sp., Acrapex njombea n. sp., Acrapex vetiveria n. sp. and Acrapex zima n. sp. All species are assigned to the A. albivena group with the exception of A. lusinga which is assigned to the A. stygiata group. We also provide supplemental descriptions for two previously described species of the A. albivena group, A. punctosa Berio, 1973 and A. sysciodes Berio, 1973, and for one species belonging to the A. stygiata group: A. brunneella Le Ru, 2014. Host plants of three species are recorded; A. brunneella and Acrapex jansei were reared on Cymbopogon pospischilii (K.Schum.) C.E.Hubb and A. vetiveria on Chrysopogon zizanioides (L.). We also conducted molecular phylogenetic analyses (using both Bayesian inference and maximum likelihood) on a multi-marker (four mitochondrial and two nuclear genes) molecular dataset encompassing 138 specimens (including 98 specimens from the A. albivena group and 23 specimens from the A. stygiata group) from 48 stemborer species. The results of the corresponding analyses support the monophyly of the two groups of interest and the species status of all newly described taxa, except for A. lusinga that was not sequenced. The phylogenetic analyses also unravel several evolutionary lineages whose precise status is pending because their DNA was extracted from larval stages.; Actualisation des connaissances de la phylogénie et de la systématique des groupes d’espèces Acrapex albivena Hampson, 1910 et A. stygiata (Hampson, 1910) (Lepidoptera, Noctuidae, Noctuinae, Apameini, Sesamiina), avec la description de neuf nouvelles espèces de la région Afrotropicale. Le genre Acrapex Hampson, 1891 (Lepidoptera, Noctuidae, Noctuinae, Apameini, Sesamiina) est un groupe diversifié de noctuelles foreuses, majoritairement distribué dans la région Afrotropicale. Dans cette étude neuf espèces nouvelles sont décrites : Acrapex abyssinica n. sp., Acrapex dabaga n. sp., Acrapex jansei n. sp., Acrapex kifanya n. sp., A. lusinga n. sp., Acrapex ngwenya n. sp., Acrapex njombea n. sp., Acrapex vetiveria n. sp. et Acrapex zima n. sp. Toutes ces espèces sont assignées au groupe d’espèce A. albivena à l’exception d’A. lusinga qui est assignée au groupe d’espèce A. stygiata. Nous fournissons également des descriptions supplémentaires pour deux espèces, A. punctosa Berio, 1973 et A. sysciodes, Berio 1973, précedemment décrites dans le groupe A. albivena ainsi que pour A. brunneella Le Ru, 2014, une espèce qui appartient au groupe A. stygiata. Les plantes-hôtes de trois espèces sont répertoriées ; Acrapex brunneella et A. jansei ont été élevées sur Cymbopogon pospischilii (K. Schum.) C. E. Hubb et A. vetiveria sur Chrysopogon zizanioides (L.). Nous avons également réalisé des analyses de reconstruction phylogénétique (utilisant à la fois l’inférence Bayésienne et le maximum de vraisemblance) sur un jeu de données moléculaires multi-marqueurs (quatre gènes mitochondriaux et deux gènes nucléaires) comprenant 138 specimens (incluant 98 specimens du groupe A. albivena et 23 specimens du groupe A. stygiata) de 48 espèces de foreurs. Les résultats de ces analyses soutiennent à la fois l’hypothèse de monophylie des deux groupes d’intérêt et le statut d’espèces des taxa nouvellement décris, à l’exception d’A. lusinga qui n’a pas été séquencé. Les analyses phylogénétiques révèlent également l’existence de plusieurs lignées évolutives distinctes dont le statut reste à définir car leur ADN a été extrait de stades larvaires

Guineagrass, Megathyrsus maximus (Jacq.) B.K.Simon & S.W.L.Jacobs, is an African grass that is invasive in Florida, Hawaii, southern Texas, and northeastern Mexico. Buakea kaeuae Moyal et al., a stem-boring African moth found only on M. maximus, was imported from Kenya and evaluated for its ability to feed and develop on Guineagrass naturalized in southern Texas. Neither larvae nor adults developed or reproduced on Texas Guineagrass.

Competitive or facilitative interactions characterise phytophagous insect communities that utilise the same resources. These interactions are often mediated by the host plant. Plant mediation influences the oviposition choices that a community of insects, sharing the same host plant make. In this context, the oviposition choices of females within a community of lepidopteran cereal stemborers namely Busseola fusca, Sesamia calamistis and Chilo partellus were studied in plant choice-experiments under laboratory and field conditions. Gravid females of each species were presented with a choice between maize plants infested by conspecific or heterospecific larvae and uninfested maize plants. The number of eggs and egg batches laid on plants were used to quantify oviposition. Results showed that none of the three stemborer species avoided oviposition on infested maize plants. In some cases a significant preference for infested maize plants were observed. Similarly, data from field trials under natural stemborer infestation, with B. fusca as the only species, showed that the wild ovipositing moths were not avoiding infested plants. Host plant mediation may influence the incidence of multi-species infestations by stemborer species often found in the field. The potential roles of herbivore-induced and egg-deposited-induced plant volatiles in this mechanism are discussed.

In this study, we review six morphologically similar species of Sesamia Guenée, 1852 from Africa, including three new species that are described: Sesamia corymbosus Le Ru n. sp., S. schoenoplectus Le Ru n. sp. and S. temberma Le Ru n. sp. These six species belong to a species complex that we hereby define as the Sesamia coniota group. Host plants of four species are recorded: Schoenoplectus corymbosus (Roth ex Roem. & Schult.) J. Raynal. for S. corymbosus and S. schoenoplectus, Echinochloa pyramidalis (Lam.) Hitschc. & Chase, Eriochloa meyeriana (Nees) Pilg., Schoenoplectus corymbosus and Typha latifolia L. for S. jansei, Tams & Bowden, 1953 and Pennisetum sp. for S. temberma. We also conduct molecular phylogenetic analyses on a multimarker (four mitochondrial and two nuclear genes) molecular dataset encompassing 36 specimens (including 32 specimens belonging to the S. coniota group). Molecular analyses allow assessing the phylogenetic relationships of five out of six species of the group Phylogénie and systématique du groupe d’espèces Sesamia coniota (Lepidoptera : Noctuidae : Apameini : Sesamiina) avec la description de trois nouvelles espèces de la région afrotropicale. Dans cette étude, nous passons en revue six espèces du genre Sesamia Guenée, 1852 distribuées en Afrique. Trois nouvelles espèces sont décrites : Sesamia corymbosus Le Ru n. sp., S. schoenoplectus Le Ru n. sp. et S. temberma Le Ru n. sp. Ces six espèces appartiennent à un complexe d’espèces que nous définissons comme le groupe d’espèce Sesamia coniota. Les plantes-hôtes de quatre espèces sont répertoriées : Schoenoplectus corymbosus (Roth ex Roem. & Schult.) J. Raynal. pour S. corymbosus et S. schoenoplectus, Echinochloa pyramidalis (Lam.) Hitschc. & Chase, Eriochloa meyeriana (Nees) Pilg., Schoenoplectus corymbosus et Typha latifolia L. pour S. jansei Tams & Bowden, 1953, et Pennisetum sp. pour S. temberma. Nous avons également réalisé des analyses de reconstruction phylogénétique sur un jeu de données moléculaires multimarqueurs (quatre gènes mitochondriaux et deux gènes nucléaires) comprenant 36 spécimens (dont 32 appartiennent au groupe d’espèce S. coniota). Les analyses moléculaires permettent d’inférer les relations phylogénétiques de cinq des six espèces du groupe

International audience; Summary: With a species count reaching almost 100 species, the genus Acrapex is the most diverse genus of sesamiine stemborers (Lepidoptera: Noctuidae: Noctuinae: Apameini: Sesamiina). Acrapex species are mostly distributed in the Afrotropics and consist of several large clades corresponding to distinct species complexes. In this study, 45 morphologically similar species of Acrapex from sub-Saharan Africa are reviewed, including 22 new species that are described: Acrapex alemuran. sp., A. barnsin. sp., A. capelongon. sp., A. congoensisn. sp., A. elgonan. sp., A. elisabethianan. sp., A. eucanthan. sp., A. grandisn. sp., A. igominyin. sp., A. inexpectatan. sp., A. ketoman. sp., A. lilomwin. sp., A. mafingan. sp., A. maketen. sp., A. marungun. sp., A. mazoen. sp., A. mlanjen. sp., Acrapex muchingan. sp., A. ngorongoron. sp., A. obscuran. sp., A. ruirun. sp. and A. wittein. sp. Supplemental descriptions for previously described species are provided as well. These 45 species are assigned to the newly defined Acrapex aenigma species group. We also conduct molecular phylogenetic analyses and molecular species delimitation analyses on a multi-marker (four mitochondrial and two nuclear genes) molecular dataset encompassing 304 specimens (including 256 Acrapex specimens from 54 species of which 16 species belong to the A. aenigma group). Molecular phylogenetics analyses recover well-supported relationships within Acrapex and support the monophyly of the newly defined group. Results of molecular species delimitation analyses are mostly congruent and tend to corroborate the status of the sampled Acrapex species. Consistent with what has been previously found in other studies, the comparison of results from distinct methods and settings for molecular species delimitation analyses allows us to assess species boundaries with more confidence.; Avec près d’une centaine d’espèces le genre Acrapex est le genre de noctuelles foreuses le plus diversifié de la sous-tribu des Sesamiina (Lepidoptera : Noctuidae : Noctuinae : Apameini). Les Acrapex sont majoritairement distribués dans la région Afrotropicale et sont composés de plusieurs clades correspondant à différents complexes d’espèces. Dans cette étude, 45 espèces morphologiquement proches d’Acrapex sub-sahariens sont étudiées, au rang desquelles figurent 22 nouvelles espèces que nous décrivons : Acrapex alemura n. sp., A. barnsi n. sp., A. capelongo n. sp., A. congoensis n. sp., A. elgona n. sp., A. elisabethiana n. sp., A. eucantha n. sp., A. grandis n. sp., A. igominyi n. sp., A. inexpectata n. sp., A. ketoma n. sp., A. lilomwi n. sp., A. mafinga n. sp., A. makete n. sp., A. marungu n. sp., A. mazoe n. sp., A. mlanje n. sp., A. muchinga n. sp., A. ngorongoro n. sp., A. obscura n. sp., A. ruiru n. sp., and A. wittei n. sp. Nous fournissons également des descriptions supplémentaires pour des espèces déjà décrites. Ces 45 espèces sont assignées au groupe d’espèces Acrapex aenigma, que nous définissons. Nous avons également réalisé des analyses de reconstruction phylogénétique et des analyses de délimitation moléculaire d’espèces sur un jeu de données moléculaires multimarqueurs (quatre gènes mitochondriaux et deux gènes nucléaires) comprenant 304 spécimens (incluant 256 Acrapex de 54 espèces dont 16 appartiennent au groupe A. aenigma). Les analyses phylogénétiques retrouvent des topologies bien supportées au sein du genre Acrapex et soutiennent l’hypothèse de monophylie du groupe d’espèces nouvellement défini. Les résultats des analyses de délimitation moléculaire d’espèces sont majoritaitement en accord et tendent à soutenir le statut d’espèce des Acrapex échantillonnés. Conformément à ce qui a été mis en évidence dans d’autres études, la comparaison des résultats de différentes méthodes et paramétrages d’analyses de délimitation moléculaire d’espèces permet ainsi d’estimer les contours des espèces avec plus de confiance.

Sources of infestation are the key elements to be considered in the development of habitat management techniques for the control of maize stemborers. Several wild plants, grasses mostly, have been identified that serve as hosts for stemborers and their parasitoids during the off-season when maize is not present in the field. However, their abundance is much lower in wild plants compared to cultivated fields. Thus, the role of wild plants as a reservoir for cereal stemborers and their parasitoids is still controversial, particularly in agro-ecosystems with reduced wild habitat. We studied the occurrence of different maize stemborers and associated parasitoids in maize stem residues and wild grasses during non-cropping seasons as potential carry-over populations to subsequent early season maize plants. Surveys were conducted in the central region of Kenya during long and short dry seasons in maize residues and wild grasses as well as during the two rainy seasons in maize plants at earlier and late whorl stages during the years of 2017 and 2018. Wild habitat had a higher species diversity than maize residues habitat, but maize residues had a higher abundance of maize stemborer species, such as Busseola fusca, Sesamia calamistis, and Chilo partellus, and of associated parasitoid species (i.e., Cotesia flavipes and Cotesia sesamiae) than wild plants. Our surveys, complemented by field parasitoid releases of C. flavipes and C. sesamiae, indicated that maize residues constitute a better refugia reservoir not only of the maize stemborers but also of C. flavipes and C. sesamiae during non-cropping seasons as compared to wild plants and, thus, might constitute in this region the main source of both stemborers and C. flavipes/C. sesamiae carry-over in maize plants during the subsequent cropping season. Thus, systematic destruction of maize residues would not help the biological control of lepidopteran stemborers. This is particularly true in areas with reduced wild habitat.

Landscape context influences population dynamics of insects and impacts biological processes within communities. It was expected that anthropogenic disturbances of the rainforest landscape in DR Congo would lead to a decreased level of noctuid stemborer egg parasitism as a consequence of a decoupling between stemborers and their naturally occurring parasitoids through dispersal. To test this hypothesis, noctuid egg batches were collected in maize fields along an anthropogenic disturbance gradient to assess change in the rates of eggs parasitism and maize plant infestation with noctuid egg batches. Our results showed that, in contrast to what was initially expected, egg parasitism increased from less to highly disturbed landscape whereas maize infestation had an inverse tendency. Discovery efficiency and mean egg parasitism were 1.416 and 1.392 times higher, respectively, in the most than in the less disturbed landscape. The numbers of eggs and egg batches per 100 maize plants were 0.55 times and 0.532 times the value in the less disturbed landscape, suggesting a dilution of the stemborer population within a large habitat patch encompassing cultivated fields and the surrounding wild host plants. It was concluded that the presence of suitable host plants enhances noctuid stemborers egg parasitism in adjacent maize fields.

Parasitoid life style represents one of the most diversified life history strategies on earth. There are however very few studies on the variables associated with intraspecific diversity of parasitoid insects, especially regarding the relationship with spatial, biotic and abiotic ecological factors. Cotesia sesamiae is a Sub-Saharan stenophagous parasitic wasp that parasitizes several African stemborer species with variable developmental success. The different host-specialized populations are infected with different strains of Wolbachia, an endosymbiotic bacterium widespread in arthropods that is known for impacting life history traits notably reproduction, and consequently species distribution. In this study, first we analyzed the genetic structure of C. sesamiae across Sub-Saharan Africa, using 8 microsatellite markers, and 3 clustering software. We identified five major population clusters across Sub-Saharan Africa, which probably originated in East African Rift region and expanded throughout Africa in relation to host genus and abiotic factors such as climatic classifications. Using laboratory lines, we estimated the incompatibility between the different strains of Wolbachia infecting C. sesamiae. We observed an incompatibility between Wolbachia strains was asymmetric; expressed in one direction only. Based on these results, we assessed the relationships between direction of gene flow and Wolbachia infections in the genetic clusters. We found that Wolbachia-induced reproductive incompatibility was less influential than host specialization in the genetic structure. Both Wolbachia and host were more influential than geography and current climatic conditions. These results are discussed in the context of African biogeography, and co-evolution between Wolbachia, virus parasitoid and host, in the perspective of improving biological control efficiency through a better knowledge of the biodiversity of biological control agents.

Ten morphologically similar species of Acrapex Hampson, 1891 (Lepidoptera, Noctuidae, Noctuinae, Apameini) from Central and Eastern Africa are reviewed, including five new species: Acrapex kafula le Ru sp. nov., A. kavumba le Ru sp. nov., A. kiakouama le Ru sp. nov., A. miscantha le Ru sp. nov. and A. simillima le Ru sp. nov. Evidence is provided to transfer the monotypic genus Poecopa Bowden, 1956 to the genus Acrapex . Host plants of five species are recorded, some of them for the first time. Acrapex kavumba sp. nov., A. miscantha sp. nov. and A. simillima sp. nov. were found on one host plant each. Acrapex mediopuncta , previously reported in West Africa from Pennisetum purpureum Schumach. , Rottboellia compressa L., Setaria megaphylla (Steud) Dur. & Schinz. and Sorghum arundinaceum (Desv.) Stapf, was only found from S. megaphylla in Central Africa. Larvae of Acrapex unicolora were collected on Andropogon gayanus Kunth, Chrysopogon zizanoides (L.) Roberty, Cymbopogon schoenanthus subsp. proximus (Hochst. ex A.Rich.) Maire & Weller, Cymbopogon pospischiilii (K.Schum.) C.E.Hubb. , Hyparrhenia diplandra (Hack.) Stapf and Setaria sphacelata (Schumach.) Moss. We also conducted molecular phylogenetic analyses (using maximum likelihood) and molecular species delimitation analyses on a comprehensive sample of 61 specimens belonging to eight of the studied species. Molecular phylogenetic analyses provided additional evidence of the synonymy of Acrapex and Poecopa , whereas molecular species delimitation analyses support the validity of the five newly described species and unravel another potential new species, only collected in the larval stage.

International audience; Twelve morphologically similar species of Acrapex Hampson 1894, (Lepidoptera, Noctuidae, Noctuinae, Apameini, Sesamiina), from Western, Central and Eastern Africa are reviewed. Eight of these species are new to science and are described: Acrapex akunamatatan. sp. and A. incrassata n. sp. from Kenya; A. gracilis n. sp., A. iringa n. sp., A. lukumbura n. sp. and A. rungwe n. sp. from Tanzania; A. soyema n. sp. from Ethiopia; and A. zoutoi n. sp. from Benin. All 12 species belong to a species complex that we hereby define as the Acrapex apicestriata group. Host-plants for three of the new species are recorded: Setaria incrassata (Hochst.) Hack. for Acrapex incrassata; Cymbopogon pospishilii (K. Schum.) C.E. Hubb. for A. rungwe; and Andropogon perligulatus Stapf. for A. zoutoi. We also conducted molecular phylogenetic analyses (using maximum likelihood and Bayesian inference) on a six gene multimarker molecular dataset (four mitochondrial and two nuclear gene fragments; 4581 nucleotides in length) consisting of 15 Acrapex species (including seven species from the apicestriata group) and four outgroups species from the subtribe Sesamiina (from genera Busseola Thurau 1904, Sciomesa Tams & Bowden 1953, Pirateolea Moyal, Le Ru, Conlong, Cugala, Defabachew, Matama-Kauma, Pallangyo & Van den Berg 2010 and Sesamia Boisduval & Guenee 1852). Both maximum likelihood and Bayesian inference analyses yield a similar and well-supported topology, which supports the monophyly of the apicestriata group.

International audience; Five morphologically similar species of Acrapex Hampson (Lepidoptera, Noctuidae, Noctuinae, Apameini), from sub-Saharan Africa are reviewed, including four new species that are described: Acrapex mondogeneta Le Ru n. sp., A. mubale Le Ru n. sp., A. robe Le Ru n. sp. and A. rubona Le Ru n. sp. These five species belong to a species complex that we hereby define as the Acrapex minima group. Host plants of three species are recorded; Acrapex minima is recorded for the first time on a host plant, Digitaria natalensis Stent; A. mondogeneta on Hyparrhenia hirta (L.) Stapf and A. rubona on Imperata cylindrica (L.) P. Beauv. We also conducted molecular phylogenetics (using both Bayesian inference and maximum likelihood) and molecular species delimitation analyses (Poisson tree processes) on a six gene multi-marker dataset (four mitochondrial and two nuclear gene fragments; 4582 nucleotides in length) of 42 specimens and 22 species, including 23 specimens from the Acrapex minima group. The results of the corresponding analyses support the monophyly of the group and the species status of the newly described taxa.

In East Africa, lepidopteran stemborers such as Chilo partellus and Busseola fusca are major constraints to production of maize, which is the main staple food crop in the region. Cereals depend on silicon (Si)-based defences to fight off herbivores. Using altitudinal ranges in the East African highlands as ecological surrogates for inferring climate change, it was shown that Si concentrations in soil and maize decreased with altitude. This was attributed, in part, to low temperatures at high altitudes, which negatively affected Si assimilation by maize. Experiments showed that B. fusca was more susceptible to Si than C. partellus . Hence the predominance of B. fusca in the highlands and of C. partellus in the lowlands could be partly explained by altitudinal differences in Si concentrations in maize plants. Therefore, a rise in temperature due to climate change should enhance the plants’ Si assimilation and as a result C. partellus might move into the higher altitudes and increasingly displace B. fusca .

Bruchidius Schilsky is a large paraphyletic genus of seed beetles (Coleoptera: Chrysomelidae: Bruchinae) which consists of multiple lineages that are usually associated with narrow sets of host-plants. In this study we focus on a group that mostly develops on wattle trees (acacias) belonging to the genus Vachellia Wight & Arn. This group originally included nine species and was designated as the Bruchidius centromaculatus (Allard) species group, but recent phylogenetic analyses revealed that these species belong to a much wider group of species with similar morphologies. For reasons of anteriority we call this enlarged group Bruchidius albosparsus (Fahraeus). Here we review the morphology of species in this group and provide new diagnoses and ecological data for 10 species. The following combinations and synonymies are proposed: Bruchidius tanaensis (Pic, 1921) (= Bruchus tanaensis Pic, 1921) comb. nov. and Bruchidius albosparsus (Fahraeus, 1839) (= Bruchus spadiceus Fahraeus, 1839) syn. nov. Four new species are also described: B. eminingensis sp. nov., B. gerrardiicola sp. nov., B. glomeratus sp. nov. and B. haladai sp. nov. Finally we carried out molecular phylogenetic analyses on a multi-marker dataset of 59 specimens and 35 species, including 14 species from the group. The resulting trees allow us to confirm the monophyly of the group of interest and provide a more detailed picture of their evolutionary relationships.

Surveys were completed in Eritrea, Ethiopia, Kenya, Madagascar, Mozambique, Tanzania, Uganda and Zanzibar to assess the lepidopteran stem borer species diversity on wild host plants. A total of 24,674 larvae belonging to 135 species were collected from 75 species of wild host plants belonging to the Poaceae, Cyperaceae and Typhaceae. Amongst them were 44 noctuid species belonging to at least nine genera, 33 crambids, 15 pyralids, 16 Pyraloidea species not yet identified, 25 tortricids and three cossids. The noctuid larvae represented 73.6% of the total number of larvae collected, with 66.3, 3.5 and 3.8% found on Poaceae, Cyperaceae and Typhaceae, respectively. The Crambidae, Pyralidae, Tortricidae and Cossidae represented 19.8, 1.9, 2.5 and 0.1% of the total larvae collected, respectively, with 90.4% of the Crambidae and Pyralidae collected from Poaceae, and 99.7% of the Tortricidae collected from Cyperaceae. The lepidopteran stem borer species diversity in the wild host plants was far more diverse than previously reported.

Surveys were carried out in Kenya, Tanzania, Uganda and Zanzibar to establish geographic distribution in the main vegetation mosaics and ecological (host plant range, feeding behaviour) characteristics of the East African noctuid stem borers. 49 wild plant species belonging to Poaceae, Cyperaceae and Typhaceae were found to harbour stem borers in the six vegetation mosaics surveyed. A total of 36 noctuid species belonging to nine genera were identifi ed from 14,318 larvae collected, out of which 17 were new to science. The species diversity varied among vegetation mosaics and host plants. Most borer species appeared to be specialised feeders with 24 species being monophagous. Species belonging to the same types (named as the Busseola Thurau 1904 and the Sesamia Guenee 1852 types) or genus harboured common ecological characteristics such as pigmentation and feeding site. The Sciomesa Tams and Bowden 1953 genus was an exception as it had a mixture of these characters. Resume. Distribution geographique et spectre d'hotes des foreurs de graminees d'Afrique de l'Est. Des enquetes ont ete conduites au Kenya, en Tanzanie, en Ouganda et a Zanzibar afi n de connaitre les caracteristiques ecologiques des noctuelles foreuses africaines tels que le spectre d'hotes, le mode de nutrition et les principales caracteristiques de developpement. 49 especes de plantes appartenant aux familles des Poaceae, Cyperaceae et Typhaceae ont ete trouvees infestees par des foreurs dans les six phytochories rencontrees. Sur un total de 14318 chenilles recoltees, nous avons identifi e 36 especes de noctuelles appartenant a neuf genres. 17 especes nouvelles ont ete trouvees. La diversite specifi que varie d'une phytochorie a l'autre et d'une plante hote a l'autre. La plupart des especes de foreurs ont ete trouvees dans les zones humides des phytochories et presentent un comportement alimentaire specialise : 24 especes sont monophages, et la plupart des huit especes oligophages montrent une preference marquee pour une ou deux plantes.