  We study the properties of 66 galaxies with kinematically misaligned gas and
stars from MaNGA survey. The fraction of kinematically misaligned galaxies
varies with galaxy physical parameters, i.e. M*, SFR and sSFR. According to
their sSFR, we further classify these 66 galaxies into three categories, 10
star-forming, 26 "Green Valley" and 30 quiescent ones. The properties of
different types of kinematically misaligned galaxies are different in that the
star-forming ones have positive gradient in D4000 and higher gas-phase
metallicity, while the green valley/quiescent ones have negative D4000
gradients and lower gas-phase metallicity on average. There is evidence that
all types of the kinematically misaligned galaxies tend to live in more
isolated environment. Based on all these observational results, we propose a
scenario for the formation of star forming galaxies with kinematically
misaligned gas and stars - the progenitor accretes misaligned gas from a
gas-rich dwarf or cosmic web, the cancellation of angular momentum from gas-gas
collisions between the pre-existing gas and the accreted gas largely
accelerates gas inflow, leading to fast centrally-concentrated star-formation.
The higher metallicity is due to enrichment from this star formation. For the
kinematically misaligned green valley and quiescent galaxies, they might be
formed through gas-poor progenitors accreting kinematically misaligned gas from
satellites which are smaller in mass.
