The Frequency Distribution of Eggs and Larvae of Anaphe venata Butler (Lepidoptera: Notodontidae) on Triplochiton scleroxylon K. Schum

  • M. O. Ashiru


The spatial distribution of the eggs and larvae of Anaphe venata Butler within canopies of its host, Triplochiton scleroxylon K. Schum situated at Araromi Village northeast of Ibadan was determined. Sampling branches of T. scleroxylon once in a spiral from base of canopy upwards was sufficient in determining the distribution of eggs and larvae of A. venata. Although the differences in the mean count of egg masses and larval groups in the lower, middle and upper canopy levels were not significant, the highest percentage of egg masses and larvae occurred on the tips of branches in the lower canopy. Sampling studies on the developmental stages of A. venata may therefore be done at the lower canopy level for best precision. Eggs and larvae are aggregated while the larval dispersion on the host suggest photo-positivity. The use of mounted, motorised elevators is proposed in order to enhance efficiency of sampling and avoid destructive sampling.

Key Words

Anaphe venata eggs larvae aggregation dispersion photo-positive 


La distribution spatial des oeufs et des larves d’Anaphe venata Butler à l’intérieur de dais de ses lavaires (Triplochiton scleroxylon K. Schum) est déterminé à Araromi une village à la nord est du Ibadan. Essayant les branches de Triplochiton scleroxylon une fois dans un spiral de la base d’un dais en haut était suffisant pour déterminer la distribution des oeufs et des larves d’Anaphe venata. Bien que les differences dans le calcue moyen des masses d’oeufs et les groupes larvaires dans les dais le plus bas, le centre et le plus haut ne soient pas significatives, les plus haut pourcentage des masses d’oeufs et de larves se produissent sur les bouts des branches dans le dais plus bas.

Les études essayantes sur les étapes dévéloppentales de A. venata peut être donc se faire au dais plus bas pour la meilleure précision. Les oeufs et les larves sont agrégés tandis que la dispersion larvaires suggère une photopositivité. L’utilité de l’ascenseur est proposé pour mettre en valeur essayant et éviter destructeur.

Mots Cléfs

Anaphe venata les oeufs les larves agrégation dispersion photo-positivité 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Ashiru M. O. (1975) Some aspects of work on insect pests of leaves and fruits of Triplochiton scleroxylon K. Schum. In Proceedings of Symposium on Variation and Breeding Systems of T. scleroxylon K. Schum. Fed. Dept. of Forest Research, Ibadan. 21–22 April, pp. 42–52.Google Scholar
  2. Ashiru M. O. (1986) The bionomics and socio-economic importance of Anaphe venata B. (Lepidoptera: Notodontidae) a defoliator of Triplochiton scleroxylon K. Schum. Ph.D. thesis, Dept. of Agric. Biology, University of Ibadan, Ibadan. 238 pp.Google Scholar
  3. Browne F. G. (1968) Pests and diseases of forest plantation trees. Clarendon Press Oxford, p. 49 and 1155.Google Scholar
  4. Golding F. D. (1942) The wild silkworms of Nigeria. Farm. and For. 3, 35–40.Google Scholar
  5. Howland P. and Bowen M. R. (1977) West African Hardwoods Improvement Project. Research Report 1971-1977—Triplochiton scleroxylon K. Schum and other West African Tropical Hardwoods.Google Scholar
  6. Jones N. and Kudler J. (1971) A survey of fruiting of Triplochiton scleroxylon K. Schum and the insects made in 1969–1970. Ghana J. Sci. 10, 93–106.Google Scholar
  7. Kennedy J. D. (1936) Forest flora of Southern Nigeria, Lagos. Government Printing Department.Google Scholar
  8. Morisita M. (1962) Iδ-index, a measure of dispersion of individuals. Res. Popul. Ecol. 4, 1–7.CrossRefGoogle Scholar
  9. Pomeroy A. W. (1923) The producion of Anaphe silk in Nigeria for export and its possible economic value. 2nd Annu. Bull. Nig. Agric. Dept. pp. 59–79.Google Scholar
  10. Roberts H. (1969) Forest insects of Nigeria, with notes on their biology and distribution. Comm. For. Inst. Paper No. 44.Google Scholar
  11. Southwood T. R. E. (1975) Ecological Methods. Chapman and Hall, London.Google Scholar
  12. Wellington W. G. (1948) The light reactions of the spruce budworm, Christoneura fumiferana Clemens (Lepidop¬tera: Tortricidae). Can. Ent. 106, 991–994.Google Scholar
  13. Yokoyama T. (1963) Sericulture. A. Rev. Ent. 8, 287–306.CrossRefGoogle Scholar

Copyright information

© ICIPE 1988

Authors and Affiliations

  • M. O. Ashiru
    • 1
  1. 1.Forestry Research Institute of NigeriaEntomology SectionIbadanNigeria

Personalised recommendations