  We have obtained high spectral resolution (R = 45900) Fabry-Perot velocity
maps of the Hickson Compact Group HCG 31 in order to revisit the important
problem of the merger nature of the central object A+C and to derive the
internal kinematics of the candidate tidal dwarf galaxies in this group. Our
main findings are: (1) double kinematic components are present throughout the
main body of A+C, which strongly suggests that this complex is an ongoing
merger (2) regions $A2$ and E, to the east and south of complex A+C, present
rotation patterns with velocity amplitudes of $\sim 25 km s^{-1}$ and they
counterrotate with respect to A+C, (3) region F, which was previously thought
to be the best example of a tidal dwarf galaxy in HCG 31, presents no rotation
and negligible internal velocity dispersion, as is also the case for region
$A1$. HCG 31 presents an undergoing merger in its center (A+C) and it is likely
that it has suffered additional perturbations due to interactions with the
nearby galaxies B, G and Q.
