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SummaryIn this study, 31 species of noctuid stemborers belonging to the genus SesamiaGuenée, 1852 (Lepidoptera: Noctuidae: Noctuinae: Apameini: Sesamiina) are reviewed. All these species are assigned to the Sesamia creticagroup sensuTams & Bowden (1953). Based on genitalic characters, several subgroups are hereby defined. Nine species belong to a species complex defined as the Sesamia albivenaHampson, 1902 subgroup; it consists of S. albivena, S. mocoensisTams & Bowden, 1953, n. stat., S. sudanensisTams & Bowden, 1953, n. stat.S. taenioleuca(Wallengren, 1863), and five new species that are described (S. aethiopicaLe Ru n. sp.from Ethiopia, S. kafuloLe Ru n. sp.from Botswana and Zambia, S. kavirondoLe Ru n. sp.from Kenya and Uganda, S. maloukouLe Ru n. sp.from Republic of Congo, and S. soyemaLe Ru n. sp.from Ethiopia). Four species belong to a species complex defined as the Sesamia creticasubgroup; this encompasses S. cretica, S. rufescensHampson, 1910, and two new species that are described (S. ihambaneLe Ru n. sp.from Mozambique and Tanzania and S. kikuyuensisLe Ru n. sp.from Kenya); two new synonyms are introduced for Sesamia cretica: Nonagria uniformisDudgeon, 1905 n. syn.and SesamiagriseldaWarren, 1913, n. syn.Ten species belong to a species complex defined as the Sesamia fuscifrontiaHampson, 1914 subgroup; this includes S. fuscifrontia, S. geyri(Strand, 1915) and eight new species that are described (S. babatiLe Ru n. sp.from Tanzania, S. babessiLe Ru n. sp.from Cameroon and Zambia, S. mabiraLe Ru n. sp.from Uganda, S. nangaensisLe Ru n. sp.from Cameroon and Republic of Congo, S. rungwaLe Ru n. sp.from Tanzania, S. simillimaLe Ru n. sp.from Benin, Cameroon, Kenya and Uganda, S. tavetaLe Ru n. sp.from Kenya and S. ulaukaeLe Ru n. sp.from Ethiopia). One species belongs to a species complex defined as the Sesamia salamaLe Ru n. sp.subgroup; this consists of S. salamaLe Ru n. sp.from Kenya and another undescribed Sesamiaspecies from South Africa. One species belongs to a species complex defined as the Sesamia vietteiRungs, 1954 subgroup.Six species belong to a species complex defined as the Sesamia wiltshireiRungs, 1963 subgroup; this groups S. wiltshireiand five new species that are described (S. djenoensisLe Ru n. sp.from Republic of Congo, S. inexpectataLe Ru n. sp.from South Africa and Zambia, S. lefiniLe Ru n. sp.from Republic of Congo, S. echinochloaLe Ru n. sp.from Botswana, Kenya, Mozambique, South Africa, Tanzania and Zambia and S. rindiniLe Ru n. sp.from Tanzania). A supplemental description of the previously described species is also provided. Novel host plant records are also provided for 11 species of the S. creticagroup. To complement the morphological study, both phylogenetic and molecular species delimitation analyses were carried out on a multimarker (four mitochondrial and two nuclear genes) molecular dataset encompassing 144 specimens representing 35 species (including 25 species from the S. creticagroup). Molecular analyses provide a well-supported phylogenetic framework for the species of interest, which are all recovered monophyletic. Molecular species delimitation analyses also support the species status of almost all sampled species. Interestingly, the inferred tree indicates that the S. creticagroup and the S. fuscifrontiasubgroup are both paraphyletic; this indicates that, while highly informative, the chosen genitalic characters in Sesamiaare not all synapomorphies.

SummaryIn this study, we review six morphologically similar species of SesamiaGuenée, 1852 from Africa, including three new species that are described: Sesamia corymbosusLe Ru n. sp., S. schoenoplectusLe Ru n. sp. and S. tembermaLe Ru n. sp. These six species belong to a species complex that we hereby define as the Sesamia coniotagroup. Host plants of four species are recorded: Schoenoplectus corymbosus(Roth ex Roem. & Schult.) J. Raynal. for S. corymbosusand S. schoenoplectus, Echinochloa pyramidalis(Lam.) Hitschc. & Chase, Eriochloa meyeriana(Nees) Pilg., Schoenoplectus corymbosusand Typha latifoliaL. for S. jansei, Tams & Bowden, 1953 and Pennisetumsp. 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. coniotagroup). Molecular analyses allow assessing the phylogenetic relationships of five out of six species of the group.

SummaryTwelve morphologically similar species of AcrapexHampson 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. incrassatan. sp. from Kenya; A. gracilisn. sp., A. iringan. sp., A. lukumburan. sp. and A. rungwen. sp. from Tanzania; A. soyeman. sp. from Ethiopia; and A. zoutoin. sp. from Benin. All 12 species belong to a species complex that we hereby define as the Acrapex apicestriatagroup. 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 perligulatusStapf. 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 Acrapexspecies (including seven species from the apicestriata group) and four outgroups species from the subtribe Sesamiina (from genera Busseola Thurau 1904, SciomesaTams & Bowden 1953, PirateoleaMoyal, Le Ru, Conlong, Cugala, Defabachew, Matama-Kauma, Pallangyo & Van den Berg 2010 and SesamiaBoisduval & Guenée 1852). Both maximum likelihood and Bayesian inference analyses yield a similar and well-supported topology, which supports the monophyly of the apicestriatagroup.

AbstractBusseola fusca(Fuller) (Lepidoptera: Noctuidae) is one of the major cereal pests in sub-Saharan Africa. Previous phylogeographic investigations on samples collected in Kenya, Cameroon and West-Africa showed the presence of three main clades (W, KI, KII) originated from populations isolated in West and East Africa around one million years ago. Demographic and phylogenetic analyses suggested that this event was followed by local demographic expansion and isolation by distance. These hypotheses were tested by a more comprehensive sampling across B. fusca’s geographic range in Africa. Comparisons of sequences of partial mitochondrial DNA gene (cytochrome b) from 489 individuals of 98 localities in southern, central, eastern and western African countries confirmed the presence of the three main clades. Phylogenetic, F-statistics, demographic parameters and nested clade phylogeographic analyses confirmed that the clades experienced geographic and demographic expansion with isolation by distance after their isolation in three refuge areas. The geographic range of clade KII, already known from East to Central sub-Saharan Africa was extended to Southern Africa. Mismatch distribution analysis and the negative values of Tajima’s D index are consistent with a demographic expansion hypothesis for these three clades. Significant genetic differentiations were revealed at various hierarchical levels by analysis of molecular variance (AMOVA). Hypotheses about the geographic origin of the three main clades are detailed.