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

  • M. O. Ashiru
Article

Abstract

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 

Résumé

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 

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References

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Copyright information

© ICIPE 1988

Authors and Affiliations

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

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