sentences:  The largest species of "Slimonia", "S. acuminata", reached a maximum length of 100 cm (39 in) whilst the smallest, "S. dubia", grew to 12 cm (5 in) in length.Though 100 cm is large for a predatory arthropod, "Slimonia" would be exceeded in length by later and more derived (more "advanced") members of the closely related pterygotid family of eurypterids, which would become the largest known arthropods to ever live.