  There exists a special class of X-ray pulsars that exhibit very slow
pulsation of $P_{\rm spin}>1000$ s in the high mass X-ray binaries (HMXBs). We
have studied the temporal and spectral properties of these superslow pulsation
neutron star binaries in hard X-ray bands with INTEGRAL observations. Long-term
monitoring observations find spin period evolution of two sources: spin-down
trend for 4U 2206+54 ($P_{\rm spin}\sim 5560$ s with $\dot{P}_{\rm spin}\sim
4.9\times 10^{-7}$ s s$^{-1}$) and long-term spin-up trend for 2S 0114+65
($P_{\rm spin}\sim 9600$ s with $\dot{P}_{\rm spin}\sim -1\times 10^{-6}$ s
s$^{-1}$) in the last 20 years. A Be X-ray transient, SXP 1062 ($P_{\rm
spin}\sim 1062$ s), also showed a fast spin-down rate of $\dot{P}_{\rm
spin}\sim 3\times 10^{-6}$ s s$^{-1}$ during an outburst. These superslow
pulsation neutron stars cannot be produced in the standard X-ray binary
evolution model unless the neutron star has a much stronger surface magnetic
field ($B>10^{14}$ G). The physical origin of the superslow spin period is
still unclear. The possible origin and evolution channels of the superslow
pulsation X-ray pulsars are discussed. Superslow pulsation X-ray pulsars could
be younger X-ray binary systems, still in the fast evolution phase preceding
the final equilibrium state. Alternatively, they could be a new class of
neutron star system $-$ accreting magnetars.
