subspecies not currently recognized by Clements or other global taxonomies.

(HBW Alive [now in BotW] mentions that it may be worthy of recognition, but doesn't recognize it; H&M recognized it in the third edition but dropped it in the fourth edition, citing Kennerley & Pearson 2010 [Reed and Bush Warblers], who state "Birds breeding in W and C Turkey appear intermediate between the nominate form and orientalis and have been described as sericea. But differences from the nominate form appear slight, variable and inconsistent. Here we treat sericea as a synonym of C. c. cetti.")