Preliminary life table of the spotted tortoise beetle,Aspidomorpha miliaris (Coleoptera: Chrysomelidae) in Sumatra
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Dissection of oothecae collected from the field after hatching clarified that the average egg mass size was 43.4 and hatching rate was 25.0%. Causes for egg mortality included: parasitism by a wasp,Tetrastichus sp. A(Europhidae) (49.8% of eggs laid), predation (12.8%), disappearance of egg masses (5.3%) and hatching failure (7.1%). An ant,Dolichoderus bituberculatus, visiting the extrafloral nectaries of the host plnts was responsible for predation and disappearance of the egg masses. The ants again attacked the larvae and pupae.
Larvae showed a gregarious habit for almost the entire larval period. Survival rates between two successive instars were low and constant, ranging from 70 to 90%, but only 1.3% of final (5th) instars become pupae (six individuals). Since the growth of host plants was extremely rapid, shortage of food was rare in larval stages. The sudden drop in numbers after 5th instar may be due to predation and/or dispersal of matured larvae from the host plants for pupation.
Pupae were attacked by three species of parasitic wasps:Tetrastichus sp. C,Pediobius elasmi (Eulophidae) andCassidocida aspidomorphae (Tetracampidae). Among the six pupae, two were parasitized, one died of disease and two disappeared. Out of 4078 eggs laid, only one emerged to adult.
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- Corbett, G. H. andC. Dover (1927) The life-history and control of some Malayan insects of economic importance.Malayan Agr. Jour. 125: 239–262.Google Scholar
- Dammermann, K. W. (1929)The agricultural zoology of the Malay Archipelago. J. H. de Bussy, Amsterdam.Google Scholar
- Kalshoven, L. G. E. (1981)Pests of crops in Indonesia (P. A. van der Laan, rev. and trans.). P. T. Ichtiar Baru-Van Hoeve, Jakarta.Google Scholar
- Maulik, S. (1919)The fauna of British India, including Ceylon and Burma. Volume on Coleoptera. Chrysomelidae (Hispinae and Cassidinae). Taylor and Francis, London.Google Scholar
- Nakamura, K. andI. Abbas (1987) Long-term fluctuations in adult numbers and egg mortalities of the tortoise beetles,Aspidomorpha miliaris andA. sanctaecrucis, in Sumatra.Chrysomela 16: 12–13.Google Scholar
- Noerdjito, W. A. andS. Adisoemarto (1986) Some insects as potential pests on sweet potato.Treubia 29: 195–205.Google Scholar
- Ogino, K. (1984) General introduction. 1–9. InM. Hotta (ed)Forest ecology and flora of G. Gadut, West Sumatra. Sumatra Nature Study (Botany), Kyoto.Google Scholar
- Schultze, W. (1908) Life histories of some Philippine Cassididae.Phil. J. Sci. 3: 261–270.Google Scholar