Multiple choice Which of the following is not a characteristic of Platyhelminthes? They are cylindrical in form and are called roundworms. They are acoelomate. They have an incomplete digestive system. They are hermaphrodites. Circulatory system, respiratory system and skeleton are absent. Reveal answer Fill a bubble to check yourself A Correct answer Explanation This is the correct option as this is not a characteristic of Platyhelminthes. Platyhelminthes are called flatworms. Aschelminthes are called roundworms.