  The nonaxial octupole shape in some nuclei with $N = 184$, namely,
$^{284}$Fm, $^{286}$No, $^{288}$Rf, and $^{290}$Sg, is investigated using
covariant density functional theories. Employing the density-dependent
point-coupling covariant density functional theory with the parameter set
DD-PC1 in the particle-hole channel, it is found that the ground states of
$^{284}$Fm, $^{286}$No, $^{288}$Rf, and $^{290}$Sg have pure nonaxial octupole
shapes with deformation parameters $\beta_{31} \approx 0.08$ and $\beta_{33}
\approx -0.01 \sim -0.03$. The energy gain due to the $\beta_{31}$ and
$\beta_{33}$ distortion is $\sim$ 1 MeV. The occurrence of the nonaxial
octupole correlations is mainly from the proton orbitals $1i_{13/2}$ and
$2f_{7/2}$, which are close to the proton Fermi surface. The dependence of the
nonaxial octupole effects on the form of the energy density functional and on
the parameter set is also studied.
