A importância da coloração contra predação e o efeito do fogo na camuflagem de Rekoa marius (Lepidoptera: Lycaenidae)

Abstract

Camouflage is a distal defense strategy common in insects and widely present in Lepidoptera. Several species of caterpillars use visual camouflage, which reduces the chances of being found by predators and increases their survival rate. For example, flowering larvae of Rekoa marius (Lepidoptera: Lycaenidae) can modify their color through diet, such strategy suggests that this butterfly caterpillar remains camouflaged in the most diverse host plants. However, events such as wildfires can impact this defense mechanism with the alteration of the coloration patterns of the remaining substrates, which can make the caterpillars more conspicuous and vulnerable to visually oriented predators. In view of this scenario, we experimentally investigated the role of camouflage against predation in R. marius caterpillars in Cerrado areas before and after a fire event. For this, artificial models of camouflaged R. marius caterpillars (similar to the color of the inflorescence of the host plant) and non-camouflaged (white) were produced, both were exposed in three species of host plants with inflorescences of different colors (pink, yellow and green); the attack rate over time by visually oriented predators was quantified. The experiments were conducted in two consecutive years, previously (2021) and later (2022) to the last fire event in the study area. The results revealed a higher predation rate in non-camouflaged artificial caterpillars when compared to those camouflaged in the area before the fire. However, there was no difference in the predation rate between camouflaged and non-camouflaged models in the burnt area. The low occurrence of predation in camouflaged caterpillar models highlights the importance of coloration acquisition in immature R. marius as a defense against predators. However, fire can negatively affect this defense mechanism by making caterpillars more apparent in their substrates and, therefore, more evident to predators.