This name is a synonym of Radula obtusiloba subsp. polyclada (A. Evans) S. Hatt..
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 35190078) with original publication details: Bull. Torrey Bot. Club 41: 607 1915.
This name was in version 1 of The Plant List, record tro-35190078.