O bicho-pau-australiano no Brasil: consumo foliar, oviposição e possíveis impactos ecológicos

Abstract

Insects of the order Phasmatodea are distinguished by their elaborate camouflage and generalist feeding habits, with Extatosoma tiaratum and Cladomorphus phyllinum being species of both scientific and educational interest. Although E. tiaratum is endemic to Australia, its presence in Brazil has raised questions about its biological aspects, including feeding, reproduction, and potential ecological impacts. This study aimed to compare the herbivory and oviposition of E. tiaratum and C. phyllinum, as well as to investigate the relationship between temperature and egg laying of E. tiaratum. The experiments were conducted at the Department of Zoology of the Federal University of Juiz de Fora, using parthenogenetic individuals kept in a controlled environment and fed Psidium guajava leaves. Leaf consumption was measured in two five-day experimental rounds, and oviposition was recorded at two fixed times (6:00 AM and 7:00 PM), subsequently correlated with mean temperature using Pearson's test. The results showed that E. tiaratum presented proportionally higher consumption relative to body weight than C. phyllinum, although the absolute herbivory rate was similar. Regarding oviposition, C. phyllinum laid eggs predominantly at night, while E. tiaratum distributed its eggs between day and night. Statistical analysis revealed a weak and non-significant positive correlation between temperature and oviposition. It is concluded that, under the conditions studied, E. tiaratum herbivory does not pose an immediate risk of agricultural impact and that temperature did not significantly influence its egg-laying rate