How to distinguish SymbolicThread arc from other curves?

For example I have a linked body with curves of symbolic thread. By a right button of mouse i do open Arc Properties menu, and at the General tab, i can see Feature Name: Symbolic Thread.
How programmatically to determine that this arc is a Symbolic Thread curve?
Arc.Name is blank, curve.Type is Arc - it dont helped me..

Given a curve object, the .AskObjectFeat method will tell you what feature created the curve (if any). I've not tested this with a symbolic thread on a wavelinked body (it may report the wave link as being the parent instead of the symbolic thread feature), but it should work.

It work correctly, thank you!