sulphur butterfly vs sulfur butterfly

sulphur butterfly and sulfur butterfly both are nouns.

Word	Noun	Adjective	Verb	Adverb
sulphur butterfly	Yes	No	No	No
sulfur butterfly	Yes	No	No	No

As nouns, sulphur butterfly and sulfur butterfly are synonyms defined as:

sulphur butterfly and sulfur butterfly: any of numerous yellow or orange butterflies

sulphur butterfly (noun)	sulfur butterfly (noun)
any of numerous yellow or orange butterflies	any of numerous yellow or orange butterflies