What is the difference between rhabditiform and filariform larvae of hookworms?

Well, sweetheart, rhabditiform larvae are the immature form of hookworms found in the soil, while filariform larvae are the infective form that can penetrate the skin of a host. So basically, one is playing in the dirt, and the other is ready to cause some trouble once it gets inside you. Hope that clears it up for ya!