Final answer:
The unusual butterfly mentioned in the question is the Limenitis archippus, also known as the viceroy butterfly. It is different from the monarch butterfly in terms of its genus.
Step-by-step explanation:
The unusual butterfly mentioned in the question is the Limenitis archippus, also known as the viceroy butterfly. This butterfly is a mimic of the monarch butterfly (Danaus plexippus) and is more distantly related from the others. It is different from the monarch butterfly in terms of its genus, as the genus of the viceroy butterfly is Limenitis.