Complex sentence: They are often referred to as intestinal worms even though not all helminths reside in the intestines; for example schistosomes are not intestinal worms, but rather reside in blood vessels.
Split into simpler sentences: They are often referred to as intestinal worms even though not all helminths reside in the intestines. For example, schistosomes are not intestinal worms, but rather reside in blood vessels.