Lensing signatures of BEC-ULDM halos. The left three columns show halos with ULDM particle mass m = 2.92 × 10⁻²² eV and angular velocities Ω = 0, 0.94, 1.25 deg Myr⁻¹ (left to right). The rightmost column shows a halo with m = 10⁻²⁰ eV and Ω = 1.25 deg Myr⁻¹, which produces a smaller core size. Top panels: simulated lensed images convolved with a 1 mas beam. Middle panels: magnification maps in the source plane. The vortices distort the critical curves and generate small, closed high-magnification loops. Bottom panels: overlays of the lensed images and magnification maps. Brightness anomalies appear where the lensed arc intersects the vortex-induced caustic loops.