  We present the detection of non-radial oscillations in a hot,
helium-atmosphere white dwarf using 78.7 d of nearly uninterrupted photometry
from the Kepler space telescope. With an effective temperature >30,000 K, PG
0112+104 becomes the hottest helium-atmosphere white dwarf known to pulsate.
The rich oscillation spectrum of low-order g-modes includes clear patterns of
rotational splittings from consecutive sequences of dipole and quadrupole
modes, which can be used to probe the rotation rate with depth in this highly
evolved stellar remnant. We also measure a surface rotation rate of 10.17404 hr
from an apparent spot modulation in the K2 data. With two independent measures
of rotation, PG 0112+104 provides a remarkable test of asteroseismic inference.
