What is Cynodon radiatus Roth ex R. & S. (Poaceae)?

Roemer and Schultes (1817) described Cynodon radiatus, basing themselves on a manuscript by A.W. Roth, copying Roth's brief diagnosis and comment. It was compared to Cynodon dactylon, differing by its larger habit, the number and direction of the spikes, and the glabrous blades and sheaths. This was of course insufficient to be able to deduce whether this was a mere form of C. dactylon or indeed a distinct species.