History of the systematics of the<i>Sesamia sensu</i>lato group of African noctuid stem borers of monocotyledonous plants (Lepidoptera)

Conlong

et al. 2010

Bull. Entomol. Res.

Currently, the systematics of the African noctuid stem borers of the subtribe Sesamiina, which include major pests of cereals, is confused. In addition, their ecology is poorly known, as are the factors influencing their evolution. In this paper, we address these shortcomings for two genera of the Sesamiina, Sciomesa Tams & Bowden and Carelis Bowden. Mixed Bayesian phylogenetic analysis, which included their host plants and two mitochondrial genes, showed the genus Sciomesa to be polyphyletic. Two new genera were created, Pirateolea and Feraxinia. The genus Carelis proved to be paraphyletic and was subdivided into two sub-genera. The genera Sciomesa, Carelis and Pirateolea (named the 'Sciomesa genus group') share morphological traits, and the phylogenetic analysis showed that they had a common ancestor living on Cyperaceae and that they were distant from the genus Feraxinia belonging to another clade which had an ancestor living on Poaceae. Seven new species were described: Sciomesa gnosia sp. n., Sciomesia bua sp. n., Pirateolea nola gen. n, sp. n., Feraxinia serena gen. n., sp. n., Carelis australis sp. n., Carelis transversa sp. n. and Carelis agnae sp. n. Ten species were sunk as synonyms: Sciomesa mesoscia (Hampson) syn. n., Sciomesa mirifica Laporte syn. n., Sciomesa constantini Laporte syn. n. and Sciomesa etchecopari Laporte syn. n. are synonyms of Sciomesa mesophaea (Aurivillius); Acrapex sparsipucta Laporte syn. n. is a synonym of Sciomesa excelsa (Laporte) comb. n.; Acrapex congitae Laporte syn. n., Sesamia minuta Laporte syn. n. and Sesamia minuscula Laporte syn. n. are synonyms of Sciomesa boulardi (Laporte) comb. n.; Acrapex bryae Laporte syn. n. and Acrapex fayei Laporte syn. n. are synonyms of Feraxinia jemjemensis (Laporte) comb. n. Eleven new combinations were created: Sciomesa excelsa (Laporte) comb. n., Sciomesa boulardi (Laporte) comb. n., Sciomesa punctipennis (Krüger) comb. n., Pirateolea piscator (Fletcher) comb. n., Pirateolea argocyma (Fletcher) comb. n., Pirateolea cyclophora (Fletcher) comb. n., Pirateolea ochroneura (Fletcher) comb. n., Pirateolea funebris (Krüger) comb. n., Feraxinia nyei (Fletcher) comb. n., Feraxinia jemjemensis (Laporte) comb. n. and Carelis biluma (Nye) comb. n.

Section: Introductionmentioning

confidence: 99%

Systematics and molecular phylogeny of two African stem borer genera,SciomesaTams & Bowden andCarelisBowden (Lepidoptera: Noctuidae)

Moyal¹,

Conlong

et al. 2010

Bull. Entomol. Res.

“…An IRD team is working on the systematics and diversity of African noctuid stemborers since 2002, using both classical morphological and molecular tools (Le Rü et al. 2006Moyal 2006; Moyal and Le Rü 2006).…”

Section: Introductionmentioning

confidence: 99%

“…Therefore, the present study aims at re-analysing the stemborer and parasitoid species composition on maize and wild host plants in the humid forest zone and the WH of Cameroon relying on the taxonomic expertise of specialists at the Institut de Recherche pour le De´veloppment (IRD, France). An IRD team is working on the systematics and diversity of African noctuid stemborers since 2002, using both classical morphological and molecular tools Moyal 2006Moyal and Le Ru¨2006).…”

Section: Introductionmentioning

confidence: 99%

Lepidopteran cereal stemborers and associated natural enemies on maize and wild grass hosts in Cameroon

Ndemah

Schulthess

et al. 2007

J Applied Entomology

In Cameroon, the noctuid Busseola fusca is the most important pest of maize. The braconid Cotesia sesamiae, which is the most common larval parasitoid of noctuid stemborers in eastern Africa, was absent on B. fusca attacking maize. Thus, it is planned to introduce several strains of the parasitoid from Kenya. Pre-release surveys were undertaken in major maize growing areas to catalogue stemborer species, and larval and pupal parasitoids on maize and four wild host plant species. On maize, B. fusca was the predominant borer in all ecozones except for the lowland coastal forest, usually accounting for 60-99%, followed by the pyralid Eldana saccharina in the forest zone and the crambid Chilo sp. in the mid-altitudes. Contrary to what was reported before, the noctuid Poeonoma serrata -and not B. fusca -was the predominant borer on elephant grass, constituting 70-96% of all borers. On wild sorghum in the forest zone, the noctuid Sesamia poephaga was the most abundant species, while on Panicum sp., Chilo sp. predominated. On Setaria megaphylla in the forest zone, Chilo sp. was the most abundant species followed by Busseola quadrata. Busseola fusca was scarce on all wild grass species, indicating that previous reports on the predominance of this pest species on wild host plants were the result of misidentifications. Three tachinid and 16 hymenopteran parasitoids were obtained, most of them from B. fusca and P. serrata, on maize and Pennisetum purpureum respectively. C. sesamiae was scarce and never recovered from B. fusca on maize. In view of the new findings, acceptability and suitability studies involving the different stemborer species identified from wild plant hosts are required to determine if they will form a reproductive sink or perennate C. sesamiae populations during the off-season when maize is scarce and B. fusca is diapausing.

“…Studying borer populations in natural landscapes requires the identifi cation of species, which may be diffi cult, particularly in noctuid borers, because of the great morphological similarity between species and some intra-specifi c variability (Tams & Bowden 1953;Holloway 1998). So the combined use of morphological and molecular data has been promoted as a powerful tool to get a better insight into the taxonomic relationships in noctuid stem borers (Moyal 2006). Molecular studies can furthermore reveal the recent history of taxa.…”

mentioning

confidence: 99%

From population to species: morphological and molecular diversity in east African stem borer species of the genusMangaBowden 1956 (Lepidoptera: Noctuidae)

Moyal

Annales de la Société entomologique de France (N.S.)

2006

Self Cite

Larvae of noctuid stem borers were collected from wild monocot plants in Eastern Africa, from Ethiopia to Mozambique, and reared to the adult stage. Three species of the African genus Manga Bowden 1956 (Lepidoptera: Noctuidae) were found, all restricted to host plants of the family Poaceae. M. melanodonta (Hampson) was collected in stems of Panicum maximum Jacquin, Setaria megaphylla (Steudel) Th. Durand & Schinz and Setaria plicatilis (Hochstetter) Engler; M. nubifera (Hampson) stat. rev., and M. fuliginosa n. sp., were both found only in stems of P. maximum. The second species was in the past sunk with M. melanodonta as a synonym, but the present study shows its validity. Descriptions are given of the new species as well as of features not yet described of known species (female habitus and male and female genitalia of M. melanodonta and M. nubifera) and of the intraspecifi c morphological variation observed in the male genitalia. Larval morphology and life habits are described. Pictures of the adults and genitalia of the other species of the genus are provided except for M. bisignata Laporte that is sunk with Busseola quadrata Bowden as a synonym (n. syn.). The molecular diversity of the collected species was studied using the mitochondrial gene Cytochrome b. A complex history of successive fragmentation events was revealed. The combination of three forces appeared to have shaped this diversity: the main paleo-climatic events (successive dry and humid periods), the geological barriers, particularly the Rift Valley, and specialization on new host plants. A molecular clock proved to be acceptable for all clades except for the species that fi rst diverged, Manga fuliginosa. The dates of the major paleo-climatic events of the last 5 million years appeared to correspond to the observed divergence events when using an evolutionary rate of 1.15% per million years, with a correction for M. fuliginosa. Isolation by the Rift Valley favoured diversifi cation in some instances, and the adaptation of Manga melanodonta to new host plants enabled the colonization of humid environments. A scenario for the evolution of the group is proposed, from its origin in Austral Africa about 5 million years ago and its northward expansion, until the recent migrations of Manga nubifera during the past million years. Résumé. De la population à l'espèce : Diversité morphologique et moléculaire des foreurs de graminées d'Afrique de l'Est du genre Manga Bowden 1956 (Lepidoptera : Noctuidae). Des larves de noctuelles foreuses ont été récoltées dans les tiges de monocotylédones sauvages en Afrique de l'est, de l'Éthiopie au Mozambique, et élevées jusqu'au stade adulte.Trois espèces du genre africain Manga Bowden 1956 (Lepidoptera : Noctuidae) ont été trouvées, dans des plantes hôtes appartenant uniquement à la famille des Poaceae. M. melanodonta (Hampson) a été récoltée dans des tiges de Panicum maximum Jacquin, Setaria megaphylla (Steudel) Th. Durand & Schinz et Setaria plicatilis (Hochstetter) Engler; M. nubifera (Hampson) stat. rev. et M. ful...