  Based on the phase-space information obtained from a multi-phase transport
model within the string melting scenario for strange and antistrange quarks, we
study the yields and transverse momentum spectra of $\phi $ mesons and $\Omega
$ ($\Omega ^{-}+\bar{\Omega}^{+}$) baryons as well as their anisotropic flows
in Au+Au collisions at RHIC using a dynamical quark coalescence model that
includes the effect due to quark phase-space distributions inside hadrons. With
current quark masses and fixing the $\phi $ and $\Omega $ radii from fitting
measured yields, we first study the ratio of the yield of $\Omega $ baryons to
that of $\phi $ mesons as well as their elliptic and fourth-order flows as
functions of their transverse momentum. How the elliptic and fourth-order flows
of $\phi $ mesons and $\Omega $ baryons are related to those of strange and
antistrange quarks is then examined. The dependence of above results on $\phi $
and $\Omega $ radii as well as on the strange quark mass is also studied.
