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Distribution, frequency of attack and seasonal incidence of the African armyworm Spodoptera exempta (Walk.) (Lep.: Noctuidae), with particular reference to Africa and southwestern Arabia
Distribution, frequency of attack and seasonal incidence of the African armyworm Spodoptera exempta (Walk.) (Lep.: Noctuidae), with particular reference to Africa and southwestern Arabia Spodoptera exempta (Walk.) is recorded very widely in Africa south of the Sahara and in adjacent parts of southwestern Arabia. It occurs intermittently through the oceanic countries of South East Asia and the Pacific as far east as Hawaii, but not in the Americas. This distribution is mapped in detail. The areas from which infestations have been reported and the frequency of attack have increased since 1970. This paper aims to help those concerned with monitoring and control of armyworm by making available the wider historical data needed for anticipating outbreaks. For the pan-African region, the monthly distribution and frequencies of incidence are presented as twelve maps showing the number of years in which infestations have been recorded in each degree-square of latitude and longitude during the period 1940-1982. In the areas to the north and south of about 4°N, the periods of attack are roughly complementary and correspond with the seasonal rains. Thus from October-November until May infestations spread progressively northwards from southern Tanzania to northern Ethiopia and Yemen, and at the same time southwards from Malawi and Zimbabwe to the south of Cape Province. From June until September infestations occur intermittently from Senegal to southwestern Arabia, but very rarely south of the equator. The northward and southward progressions of outbreaks can be attributed to the migration of the moths on the wind. The scarcity of reports from all parts of the region in September-October and the start of the next season in the area between southeastern Kenya and Zimbabwe lend support to the alternative theory that outbreaks may develop from populations that remain at low density, particularly within this area. Evidence from other disciplines supporting both theories is outlined. Sequencies of attack do not follow exactly the same pattern each season. To enable years with events analogous to the current one to be identified, the range of recorded variations is appended as a series of maps showing month by month the distribution of S. exempta infestations over the last 43 years. For each territory there is an index to the years and months when outbreaks were recorded, and a summary of the monthly frequencies of occurrence. The incidence and importance of S. exempta in each country is summarised
Excavations at Azoria, 2003–2004, Part 2: The Final Neolithic, Late Prepalatial, and Early Iron Age Occupation
This article constitutes the second of two reports on fieldwork conducted at Azoria in eastern Crete during the 2003 and 2004 excavation seasons. Evidence of Final Neolithic and Early Iron Age occupation and traces of Late Prepalatial activity were found underlying the Archaic civic buildings on the South Acropolis, particularly along the southwest terrace. The recovery of substantial Final Neolithic architectural and habitation remains contributes to our understanding of the 4th millennium in eastern Crete. Stratigraphic excavations have also clarified the spatial extent of the settlement from Late Minoan IIIC to the Late Geometric period, and brought to light evidence for the transition from the Early Iron Age to the Archaic period, and the transformation of the site in the 7th century B.C
WormBase: A data management and information system for forecasting Spodoptera exempta (Lepidoptera: Noctuidae) in Eastern Africa
Forecasting and information services on nutgrass armyworm, Spodoptera exempta (Walker), have been in operation in East Africa since 1969. Using current season and historical data from moth traps, together with outbreak and meteorological data, the probability of outbreaks in administrative areas can be predicted for the following week. WormBase, a database and information system, was developed to provide improvements in access to the data, data interpretation and synthesis, presentation of forecasts and information, forecast evaluation, and training of forecasters. The development and function of WormBase, written in dBASE IV for the use on IBM-compatible, PCs, is described. The database management section of the system provides facilities for entering, browsing, plotting and printing data. The forecasting tools section provides a range of programs that assist with specific tasks routinely undertaken by forecasters, including production and verification. WormBase is currently in use in Kenya and Tanzania