Physiological characteristics of the Large Copper butterfly, Lycaena dispar (Lepidoptera: Lycaenidae)

Abstract

To establish an indoor-rearing system for the Large Copper butterfly, Lycaena dispar and the Small Copper butterfly, Lycaena phlaeas, the effect of temperature, photoperiod and host plants on larval development was investigated. The larvae of Lycaena dispar fed on Rumex crispus, whereas the larvae of Lycaena phlaeas ate both Rumex crispus and Rumex acetosa. The duration of the larval period of Lycaena dispar was 13.8 days on R. crispus and that, of Lycaena phlaeas was 15.9 days and 15.2 days on R. acetosa and R. crispus respectively. Laboratory experiments show that the Large Copper larvae are able to feed on other Rumex species without harming their overall survival and can utilize these alternative host plants at least as efficiently as their natural host plant. This result suggests that plant chemistry is not responsible for their lack of utilization of the alternative host plants in the wild. Host plant choice by ovipositing females was measured with the two alternative hosts. Lycaena dispar preferred R. crispus to R. acetosa, wheareas Lycaena phlaeas preferred R. acetosa to R. crispus. Temperature has been proposed as an important determinant of developmental rate, lifespan and mortality in invertebrates. As temperature increased, length of the developmental period gradually decreased. The developmental period of the Large Copper larvae was 11.0 days and 28.5 days at 30 o C and 17.5 o C, respectively.