Which one or more of the following statements accurately reflects our understanding of platyhelminth phylogeny? Select all that apply.

The free-swimming larval stage of some turbellarians is called a/an

Class Trematoda Is most commonly referred to as

Annulus refers to

Planarians typically do not self-fertilize because

The free-living flatworms are classified in the class

Annelid worms typically possess ALL of the following digestive structures: mouth, pharynx, esophagus, crop, gizzard, intestines, anus.

In turbellarians, the nervous tissue is concentrated anteriorly in clusters of neurons called

Flukes in the subclass Digenea always have two or more

Parapodia in polychaetes act as