Antipodally symmetric nongeodesic spherical curve
= Antipodally symmetric nongeodesic spherical curve
For sufficiently small nonzero $\varepsilon$,
$$
\gamma(\theta)=
\frac{(\cos\theta,\sin\theta,\varepsilon\sin3\theta)}
{\sqrt{1+\varepsilon^2\sin^23\theta}}
$$
is an embedded antipodally invariant curve on the round sphere. It is not a great circle and hence not a geodesic, while the antipodal isometry exchanges its two complementary discs.