  We consider a class of stationary and axisymmetric wormhole spacetimes that
is closely related to, but not identical with, the class of Teo wormholes. We
fix a point $p$ (observation event) and a timelike curve $\gamma$ (worldline of
a light source), and we characterize the set of all past-oriented lightlike
geodesics from $p$ to $\gamma$. As any such geodesic corresponds to an image of
the light source on the observer's sky, this allows us to investigate the
lensing properties of the wormhole. As a main result, we prove with the help of
Morse theory that, under very mild conditions on $\gamma$, the observer always
sees infinitely many images of $\gamma$. Moreover, we study some qualitative
features of the lightlike geodesics with the help of two potentials that
determine the sum of centrifugal and Coriolis forces of observers in circular
motion for the case that the observers' velocity approaches the velocity of
light. We exemplify the general results with two specific wormhole spacetimes.
