Complex non-aerial contests in the lekking butterfly Charis cadytis (Riodinidae)

Lekking butterflies typically defend territories using acrobatic aerial pursuits. Focal-method observations on marked Charis cadytis in SE Brazil revealed an unusual lek organization in which contest males disputed small core areas, whereas non-combative satellite males perched just outside their borders. Territorial interactions commonly began with two adversaries facing one another in a slow, non-contact ascending flight seemingly related to assessment. In disputes that continued, rival males perched on leaves where they engaged in one or more pushing bouts separated by short pursuits. In these sumo-like contests, obliquely facing males pushed their partially opened wings against one another until one was tilted sideways and flew off. Contest structure may be controlled by intruders that, by perching, provoke low-intensity contests that help prolong their stay in high-quality mating areas.