On the Biology of Godyris zavaleta caesiopicta (Lepidoptera: Nymphalidae: Ithominae)

Various aspects of the biology of the Ithomiine butterfly Godyris zavaleta caesiopicta (Niepett), also known as G. z. sorites Fox, are presented for the first time. Field observations on habitat, adult habits, and oviposition were made in a ravine forest in the central highlands of Costa Rica, a region where the Ithomiine fauna is very rich. The butterfly is a forest species and eggs are laid singly on Solatium brenesii Morton & Stan (Solanaceae), an understory tree. The life stages and egg-to-adult developmental time (about 33 days), as studied in the laboratory, are described. The larva and pupa are cryptically colored, and the resting behavior of the larva is also cryptic. It is suggested that selection favors cryptic coloration and behavior in immatures of many Ithomiinae to reduce predation by visually-hunting predators with learning abilities during a critical period when systemic toxicity is being perfected during ontogeny. Crypsis is also effective against non-learning visual predators. But larvae may succumb to other forms of mortality, including microbial diseases that infect larvae through ingestion. A secondary consequence of this may provide a feeding niche for the larvae of the saprophytic fly Fannia canicularis (Linneaus). The strong sexual dimorphism in adult coloration is believed to provide a means for this species to enter into different mimicry complexes with other Ithomiinae, Heliconiinae, and Danainae. The hypothesis is discussed that the high richness of Ithomiinae in this region is due to pronounced divergence in larval host plants among the rich solanaceous flora found here.