The hatching behavior of two butterfly species

While choice for oviposition sites and caterpillar behavior have been largely studied in Lepidoptera, the same has not happened with the egg stage, especially the moment of hatching, when the caterpillar gains the outside world. However, this is one of the first stereotyped behaviors on the life of these individuals, occurring when they are most vulnerable. Thus, it is expected that efficient, energy-saving hatching strategies are favored by natural selection. This study aims to describe and illustrate in detail the characteristic hatching behavior of two species of Brazilian butterflies: Marpesia chiron (Nymphalidae) and Heraclides anchisiades (Papilionidae). The first has a complex behavior including two steps: 1) the larva eats pieces of chorion between the carennae, and 2) it clips the carennae off to form a dorsal lid through which it is able to pass. The second has a simpler procedure: 1) larva starts biting random areas at the dorsal surface of the egg until finding an area of clearer, probably thinner chorion, 2) larva keeps biting this area until forming a dorsal lid. The hatching behaviors of other butterfly species are also discussed. It is stated that hatching behavior is related to egg morphology, and that these behavioral and morphological traits evolve together. We propose that hatching behavior should be described with more details in life history studies, and that there is great potential for ecological and taxonomic investigation on the subject. With further studies, other interesting patterns are yet to be discovered for Lepidoptera and other insects. (FAPESP, CNPq).