---

Many thanks, friends! We had a super discussion!
To Paul:
I wanted to make it easier for the family expert - to look at ONE thread is done quicker as to open several threads, and also comparison is given easier. Non-related taxa deserve different threads, of course.
To Valery:
Chaetorellia is the same individual, so sex should not change...:D
Euphranta is termed predator, though it doesn't eat whole animals. However, it destroys whole organisms, i. e. seeds. A seed equals a whole plant, only in a very undeveloped, and dormant, state. That might be an explanation for the term "predator" in these cases.
Best whishes, Sundew