MEPS prepress abstract  -  DOI:

Inferring labrid functional roles through morphological and ecological traits

G. C. Cardozo-Ferreira*, R. M. Macieira, R. B. Francini-Filho, J. -C. Joyeux


ABSTRACT: The functional approach, using morphology and/or ecological traits, allows grouping of species which play similar roles in an ecosystem. Although species may have unique functions, some may overlap in key morphological traits, leading to similar functions (i.e., functional redundancy). To understand the functional roles of southwestern Atlantic labrids, we analyzed 21 species focusing on morphological characteristics linked to habitat use, feeding habits, and swimming ability and further taking ontogeny into account by analyzing three size categories (small, medium and large) that vary in life history aspects. A comprehensive functional analysis using 11 functional traits defined according to 16 morphological measurements was performed to generate a consensus tree that segregated species into nine functional groups. Body elongation was the most important characteristic separating parrotfishes from wrasses. Small size-class were separated from the medium and large size-classes wrasses and parrotfishes through, respectively, eye size and eye positioning. Thalassoma noronhanum was grouped with invertivorous species, despite its classification as a planktivore in previous studies. This species, together with Xyrichtys splendens and Scarus zelindae showed no size-related shifts in functional role with increasing size. Although recognized as members of different trophic guilds, different size classes of different labrid species may play similar functional roles. This suggests the need for taking size and species identity into account when measuring functional diversity and redundancy in reef ecosystems, key features for the maintenance of health and robustness (i.e., resistance/resilience) of reef systems.