In the last decade considerable interest has emerged in understanding and modeling the flow behavior of concentrated wormlike micellar solutions. A significant advance was made through the two-species modeling approach originally proposed by Vasquez, Cook, and McKinley. In the present work we revisit their model from a nonequilibrium thermodynamic perspective. By employing an extension to the nonequilibrium treatment of chemical reaction kinetics for media with an internal structure, we develop a thermodynamic model that closely resembles the one based on more ad hoc assumptions. Thus, we not only validate that model, but now also have a mechanism to systematically produce further refinements. One particular refinement, namely, the inclusion of an additional intermediate length species, is explored. (C) 2013 Elsevier B.V. All rights reserved.