Coxeter groups and meridional rank of links.

We prove the meridional rank conjecture for twisted links and arborescent links associated to bipartite trees with even weights. These are substantial generalizations of pretzel links and two-bridge links. Lower bounds on meridional rank are obtained via Coxeter quotients of the groups of link complements. Matching upper bounds on bridge number are obtained using the Wirtinger number of a link diagram, a combinatorial technique developed in conjunction with this work.