Phalloidin is a bicyclic peptide belonging to a family of toxins isolated from the deadly Amanita phalloides “death cap” mushroom and is commonly used in imaging applications to selectively label F-actin. Fluorescently-labeled phalloidin has virtually identical binding properties with actin from different species including plants and animals. Phalloidin binds F-actin with high selectivity while Alexa Fluor® 594 provides red fluorescence of unparalleled brightness and photostability. Demonstrating very little nonspecific staining, Alexa Fluor 594® phalloidin allows high-contrast discrimination of actin