We present the recent discovery of a new subdwarf B variable (sdBV), with an
exceptionally low surface gravity. Our spectroscopy of J20136+0928 places it at
Teff = 32100 +/- 500, log(g) = 5.15 +/- 0.10, and log(He/H) = -2.8 +/- 0.1.
With a magnitude of B = 12.0, it is the second brightest V361 Hya star ever
found. Photometry from three different observatories reveals a temporal
spectrum with eleven clearly detected periods in the range 376 to 566 s, and at
least five more close to our detection limit. These periods are unusually long
for the V361 Hya class of short-period sdBV pulsators, but not unreasonable for
p- and g-modes close to the radial fundamental, given its low surface gravity.
Of the ~50 short period sdB pulsators known to date, only a single one has been
found to have comparable spectroscopic parameters to J20136+0928. This is the
enigmatic high-amplitude pulsator V338 Ser, and we conclude that J20136+0928 is
the second example of this rare subclass of sdB pulsators located well above
the canonical extreme horizontal branch in the HR diagram.Comment: 5 pages, accepted for publication in ApJ Letter
