You should be able to see butterflies flitting through the air when you are exploring. You can then click on them and catch them. They can then be put in a terrarium from your inventory (where they appear once caught) or sold to Langraab Insdustries Science Facility.
The most common creature in the butterfly category is a moth. As such it is only worth 5 Simoleons. The rarest however is the Rainbow Butterfly, worth a lucrative 1,080 Simoleons. The complete list is below:
Moth: 5 Simoleons
Monarch: 10 Simoleons
Zephyr Metalmark: 25 Simoleons
Red Admiral: 35 Simoleons
Mission Blue: 50 Simoleons
Green Swallowtail: 90 Simoleons
Royal Purple Butterfly: 150 Simoleons
Silver Spotted Skipper: 325 Simoleons
Zebra Butterfly: 650 Simoleons
Rainbow Butterfly: 1,080 Simoleons
The more expensive they are, the rarer they are. Some possible locations for the rarer ones are below however. While the locations below are reliable, clearly butterflies have their own minds and may not simply appear for you the first time you look. Perseverance is the name of the game. Similarly, some locations such as Pleasant Rest Graveyard have lots of different types. You will just have to keep looking until you find the rarities listed below.
 Collecting butterflies |
The Rainbow Butterfly can be found at Pinochle Pond. This is located directly north of the town, as far north as you can get before hitting the hills. You may also be able to find it in the land north of Pleasant Rest Graveyard.
The Zebra Butterfly likes to live nearby too, so explore the surrounding area of Pinochle Pond among the trees.
The Silver Spotted Skipper can be found on the beach, near the icebox and patio area. You may also find it near the Pleasant Rest Graveyard and Pinochle Pond.
