Meeting Abstract
We reconstruct the evolutionary history of Anostomoidea, one of the most ecomorphologically diverse components of the Neotropical fish fauna, and investigate why some anostomoid clades have diversified greatly in oral jaw shape and coloration, while others primarily diversified internally. Though morphological and molecular phylogenies share broad congruence, their conflicts suggest oral jaw shape convergence within Anostomidae and that numerous features of the pharyngeal jaws and other systems appear plesiomorphic for the superfamily rather than synapomorphic for Anostomidae and Chilodontidae. Gill arch shape has diversified throughout the superfamily’s history, and may represent an axis of ecomorphological divergence for the detritivores in family Curimatidae, which are difficult to distinguish externally, and the trophically diverse members of Anostomidae and Chilodontidae. Evolutionary dynamics in Prochilodontidae differ and indicate early fixation of a highly specialized bauplan that allows prochilodontids to achieve relatively large body and population sizes but affords little opportunity for subsequent diversification. Overall, our results illustrate how combining molecular phylogenetics with osteology, geometric morphometrics, and comparative phylogenetic methods can spark new discoveries about diversification, ecomorphology and character evolution.
