Population dynamics of a tropical lepidopteranCatopsilia crocale (Pieridae)

Abstract

Extensive field observations were undertaken to study the population dynamics of the larvae of Catopsilia crocale in the Madurai Kamaraj University campus during the years 1980-81 and 1981-82. Though oligophagous, C. crocale adopted 'monophagic strategy' for oviposition and larval feeding. Seasonal changes in the nitrogen content of the food Cassia alata leaf influenced the pupal/adult weight and oviposition. Commencement of rain triggered the reproductive activity and continued precipitation facilitated maximum egg deposition. Of total egg production in a year, about 80 % was oviposited during northeast monsoon (September-December) and the rest during the south-west monsoon (May-August). Egg, I instar, V instar and pupa suffered more mortality than the other life stages. Ofthe total number of eggs laid, about 1·01 o,~emerged as adult and 98·99~.~died during the process of larval and pupal development.

Prediction of assimilation efficiency of lepidopterans

“…However, leaf water content of some trees (e.g. Cassia alata; Christopher 1983) is as high as that of some forbs and Catopsilia crocale feeding on C. alata leaf displays as high Ase as those feeding on forbs containing 85% water content. It is therefore suggested that there is a need for the collection of more information on this aspect before the observation of Scriber could be confirmed or contradicted.…”

Study the Biology of Common Castor Butterfly, Ariadne merione merione (Cramer) (Nymphalidae: Lepidoptera)

“…The three early stages and adults can be found in their natural habitat all year. Rainfall appears to be the most essential component in A. merione merione Cramer, as it is in Catopsilia crocale [8] and Catopsilia pyranthe [9]. Precipitation during the North-West monsoon most likely influenced host plant reproduction.…”