Triangulation in o-minimal fields with standard part map

In answering questions from arXiv:0901.2337v1 we prove a triangulation result that is of independent interest. In more detail, let R be an o-minimal field with a proper convex subring V, and let st: V \to k be the corresponding standard part map. Under a mild assumption on (R,V) we show that definable subsets X of V^n admit a triangulation that induces a triangulation of its standard part st(X).