Ecological Guilds Display Different Morphological Traits in Tadpoles Inhabiting Neotropical Streams

Abstract. Tadpoles display a wide variation in both ecology and morphology. Their ecomorphological variation can be characterized by classification schemes based on specific traits or quantifying traits representing ecological differences. Here, we describe the ecomorphospace of tadpoles inhabiting Atlantic Forest streams and compare it to a widely used ecomorphological guild classification scheme. Ecomorphological traits were quantified from linear measurements of the larval body plan, oral disc position, and flagella presence. We recorded 19 tadpole species classified into seven ecomorphological guilds. Nektonic and neustonic species were clear-cut segregated from the remaining guilds. Nonetheless, the benthic-nektonic axis of ecomorphological variation harbors an intermediary guild between the nektonic and the benthic species. A clustering approach failed to retrieve the ecomorphological guilds primarily by not discerning differences among benthic specialized guilds. Hence, despite the common application of ecomorphological traits to characterize tadpole functional diversity, it seems that alternative traits are necessary to achieve such a goal.