The Amazonian cichlid Satanoperca displays the unique behavior of winnowing, feeding by swallowing and sifting mouthfuls of sediment to reveal food. Sediment type appears to affect their foraging and swimming behaviors. We investigated several key traits involved in swimming mechanics in Satanoperca to test their capabilities for plastic response in various sediment types. We found significant differences in mean shape among treatments groups for various skeletal traits, which reveals their integrative and modular nature.