sqlite where clause returns no rows

sqlite 3.6.13

.schema runs yields

CREATE TABLE runs (id INTEGER PRIMARY KEY, 
               runname    TEXT DEFAULT 'norun',
               ....

executing

select runname FROM runs ORDER BY runname DESC limit 10;   *returns*

2015ww27.3c
2015ww27.3b
2015ww27.3a
201528.3c
201528.3b
201528.3a
201528.2z
201528.2y
201528.2x
201528.2s

but executing

select runname FROM runs WHERE runname = '210528.2y';

doesn't fail but doesn't return one row as expected.

I've pulled out most of my hair over this - field is declared TEXT so single-quotes are appropriate to use. What's wrong here?

TIA,

Still-learning Steve