sentences:  Some traits that appear to be unique to "S. acuminata" have been described based on specimens housed at the Doncaster Museum and Art Gallery, including rows of pustulues (bulges) along the marginal rim of the body and appendages.In some arthropods, pustules serve as attachment points of setae (bristle- or hair-like structures with sensory functions).Similar pustule rows have been discovered in the other eurypterid "Drepanopterus abonensis", a sweep-feeder that used the marginal rim to search the substrate of its living environment for prey.