Abstract Zebra stripes, characterized by periodic banded structures in the energy‐L shell spectra of energetic electrons in the Earth’s inner radiation belt, are understood to result from the azimuthal drift of electrons perturbed by prompt electric field perturbations. Using high‐resolution electron measurements from the Macao Science Satellite‐1, we report the first observation of novel extra stripes coexisting with conventional zebra stripes. Analysis demonstrates that these extra stripes originate concurrently with their conventional counterparts and evolve following the drift echo hypothesis. Both stripes are successfully reproduced by test particle simulations employing an empirical electric field model. We interpret the extra stripes as indication of non‐m=1 $m=1$ components in the electric field perturbations, in contrast to the traditional m=1 $m=1$ mode that drives the conventional stripes. These findings provide new insights into the structure of electric field perturbations and their role in electron dynamics in the inner radiation belt.

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