Dreissena-polymorpha
Guides
Macromia illinoiensis
swift river cruiser, Illinois river cruiser
Macromia illinoiensis, commonly known as the swift river cruiser or Illinois river cruiser, is a dragonfly species in the family Macromiidae. The aquatic larval stage has been extensively studied due to its interactions with the invasive zebra mussel (Dreissena polymorpha), which frequently colonizes larval bodies. Research demonstrates that zebra mussel attachment impairs larval foraging behavior, reducing prey capture efficiency and altering burying behavior. Mussel colonization creates a positive feedback loop where colonized larvae bury more shallowly, increasing further colonization risk. These effects are density-dependent and reversible when mussels are lost, typically at molting. The species' life cycle spans aquatic and terrestrial habitats, making population impacts from mussel colonization potentially significant for ecosystem dynamics.