I'm looking for the correct translation of rhotrix/rhotrices to portuguese language. I wonder if it's rotriz/rotrizes, as we have "matrix/matrices" to "matriz/matrizes", but Mr. Google didn't help ;)...!!!
If not documented in dictionaries, analogy may very well satisfy you in this concern, and so "rhotrices" will work. Still, in such cases regularity is not an odd choice! Rhotrixes may be accepted as well.