No field trip was set for this day due to work and I was just heading to my Sunday shift when I managed to observe three butterflies, including one unidentified white, during rather weather conditions consisting of overcast, no winds and 24°C (3:35 PM).
While A. urticae was resting on a wall, V. cardui was flying across the street in front of my home. The unidentified white, like V. cardui, flew to my neighbor's property.
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Note (22 June): The unidentified white turned out to be a P. rapae.