Estrutura da comunidade de helmintos parasitos de Bothrops atrox (Linnaeus, 1758) (Serpentes: Viperidae) da Amazônia Oriental brasileira

Abstract

Snakes play an important role in the life cycles of a wide variety of parasitic helminths, acting as both definitive and intermediate hosts. Several factors can influence the diversity, composition, and structure of parasite communities associated with these reptiles. Bothrops atrox, a venomous snake belonging to the family Viperidae and widely distributed throughout the Amazon, is of great medical relevance. Despite having a relatively well-documented helminth fauna, gaps remain in our understanding of the parasite-host dynamics involving this species. Therefore, the objective of this study was to analyze the diversity and structure of the helminth community of B. atrox in two localities within the Brazilian Amazon. This dissertation is structured into two chapters. In the first, we present results from a comparative analysis of the helminth community structure in B. atrox from two contrasting Amazonian environments: ombrophilous forest and natural open fields. Our analyses revealed a higher abundance of parasites in hosts from forested areas, and a positive correlation between host body size and parasite abundance. This is the first study specifically dedicated to investigating the diversity and structure of helminth communities in B. atrox across different ecosystems. In the second chapter, we describe a new species of the genus Kalicephalus, based on morphological characteristics and molecular data. This species showed the highest levels of abundance, dominance, and prevalence in forest communities. The chapter also brings new insights into the evolutionary history of the genus, contributing to a better understanding of its diversity and evolution. Thus, our study provides new data for understanding the diversity and ecology of helminth parasites of snakes in the Amazon.