Rearing the African Grass Blue Butterfly Zizeeria knysna: Toward the Establishment of a Bioindicator in African Countries

Abstract

Urbanization and environmental pollution have increasingly become important issues in African countries. For environmental risk management, it is important to conduct field surveys for potential surrogate species and establish their ecotoxicological rearing experiments. A rearing system for the pale grass blue butterfly Zizeeria maha (Lepidoptera, Lycaenidae) has been successfully employed in Japan for the assessment of human-living environments, including rural and urban areas. A phylogenetically related species, the African grass blue butterfly Zizeeria knysna, lives in human residential environments widely in African countries. Thus, this species is potentially useful as a similar bioindicator in Africa. This paper reports the establishment of a simple and economical rearing system for Zizeeria knysna as well as some morphological traits of the immature and adult stages of this species. Females were obtained in central Kenya and confined in a meshed cage where eggs were readily obtained. Hatched larvae were reared on a natural host plant Oxalis corniculata. The failure rate of eclosion from pupae to adults was 6.5%, and the reared adult individuals showed normal color patterns, demonstrating the high efficiency of this rearing system. The rearing method for Zizeeria knysna in the present study may provide a basis for future human-living environmental assessments in Africa.