The 金蝴蝶 is a harmless 小动物. It is a rare, golden recolor of an ordinary 蝴蝶.
They have a 1/150 chance of spawning in place of a regular Butterfly.
As with all other golden critters, it can be caught with a 虫网 and sold for 10.
It can be used as 鱼饵 and along with the other golden bait critters has a bait power of 50%, the highest usable value among bait (along with the 大师诱饵), excluding the 松露虫.