@thomaseverest In my opinion, they're distinct. They have more or less the same range. I haven't seen intermediates. Brown removed Scala berryi Dall 1907 and Scala rectilaminata Dall 1907 from the synonymy of Scala sawinae Dall 1903, choosing S. rectilaminatum as the valid name. I can't link to the google book you're citing. Can you send a plain citation?

Brown (2019) is at http://dx.doi.org/10.11646/zoosymposia.13.1.17. I think it's open access. If not, email me at b2neville@gmail.com, and I'll send you the pdf. This is the paper in which he separates S. berryi and S. rectilaminatum from the synonymy of S. sawinae, with which I absolutely agree. E. catalinae is nowhere mentioned in the paper. E. catalinENSE is mentioned in the paper and is distinguished from E. sawinae.

Brown (2018) did not satisfy ICZN availability until the paper came out later in the year. The online publication (15 Feb 2018) does not meet the requirements of ICZN 8.5.3. The criteria of availability are fulfilled in the print version, which is bears a cover date of 2019 and a copyright date of 2018, but does not bear a specific date of publication. My copy was downloaded 2 January 2019, which implies that it was available earlier, probably in December 2018.. Unfortunately, at least one species was cited and compared from the electronic publication before they were made available, so that should properly be cited as Murdochella turritelliforms 'L. Brown' Campagnari & Geiger 2018. Again, I can send the pdf, if you want. He just lists the species from DuShane (1979), including both E. catalinae and E. sawinae, uncritically. I'm currently in Florida and don't have access to my complete library, and I don't have the McLean electronically. For some reason, I can't remember every one of the 4500 ep references individually! I wish people would stop playing fast and loose with epitoniid taxonomy!